The RWE Power AG Ville/Berrenrath coal refinery in Hürth, Germany, produces ground lignite powder for industrial customers. The drying and grinding systems at the site process 1.9 million t/a of raw lignite (approximate water content 55 per cent) and produce about 0.64 million t/a of dry lignite powder (water content about 11 per cent).

Coperion GmbH (www.coperion.com), recently supplied and successfully commissioned a wear-protected rotary valve for the RWE Power AG Ville/Berrenrath coal refinery. The rotary valve type ZXQ with a diameter of 600mm, feeds dry lignite into a pneumatic conveying system that transports the material from a new vertical roll mill to the storage silos. The conveying pressure of the system ranges from 0.9 to 1.1bar. The rotary valve is designed for a capacity of 60t/h, however, a peak performance of approximately 80t/h has already been recorded.

From the outset, this application has demonstrated the advantages of a rotary valve over screw pumps that are normally used for feeding.

The rotary valve does not constitute a potential igniting source, as the circumferential speed at the normal operating rate is below 1m/sec. The valve is also available in a flame resistant version in accordance with the respective explosion protection concept required for the process.

With an operating power requirement of only 4kW, compared to approximately 100 kW in the previous system, tremendous electrical power savings are possible. In addition, simple maintenance and long maintenance intervals lower operating costs even further.

Due to its lightweight design and low operating speeds the valve only requires a compact, simple foundation. These features also result in lower noise emissions.

The tightness of the valve makes it suitable for 'light', fluidised products such as dry lignite with bulk densities below 600kg/m³ because sealing is achieved by precise gap dimensions and not by compression of a bulk material plug.

The rotary valve tightness is equally effective in partial load and full load operation. Therefore, start-up of the mill can be mastered without the problems that previously occurred with insufficient sealing in partial load operation using a screw pump.

In another RWE (www.rwe.com) Ville/Berrenrath coal refinery, a rotary valve of the same design achieves conveying capacities up to100t/h. The material particle size for this application is coarse but fluctuates considerably and in spite of this potential difficulty the rotary valve ensures a constant high level of tightness at the required filling level. This also occurs in partial load operation and is not affected by variations in the bulk material properties.

The soft rock and mineral mining is done in multiple stages. At the mine the rock is blasted and the rock mass is transported with big dumpers to primary and secondary screening and crushing stations where the material is stored to wait for processing.

From the screening and crushing stations the material journey continues to power plants, different storage areas, classification sites or for further transportation towards harbours where the material is yet again stored to wait. This process undeniably results waste material at screening and crushing stations, unwanted costs at waste disposal and storing, unnecessary fuel consumption and simply waste of time.

The process has for decades been this way: the material is transported to the machines. 

After years of careful studies and feedback from customers ALLU has now introduced this mobile solution also for soft rock and mineral mining sector.

“We strongly believe, that this method will be the future and many soft rock and mineral mining sectors will benefit from this mobile solution”, states the Business Line Manager Mr Fredrik Dromberg who has been involved in developing this new attachment from the beginning. 

“We’ve been selling the ALLU Screener Crushers for years for coal mining sector in Asia, where the normal sized construction wheel loaders and excavators are widely used as carriers at the mines. The word-of-mouth caught us by surprise though and we started getting inquiries for suitable units for mining excavators and wheel loaders and we had nothing to offer. We started to investigate further,” Mr Dromberg continues.

The investigation resulted the ALLU M Series attachment that processes the material already at the mine. The ready screened and crushed material can be now transported directly from the mine to the power plants or harbour in only two-step process: processing and transporting. The ALLU M Series attachment transforms the carrier (loader or excavator) into a high capacity mobile crusher or screener. The carrier mounted with the M Series attachment crushes the material, separates hard unwanted impurities in the rock mass while loading the dump truck or conveyor system. The material that is considered as waste can now be left to the mine. 

The ALLU M Series attachment only needs fuel from the carrier, no electricity or other source of power is needed.

In mining any operation it is recommended to use an excavator as carrier because of its working speed & reach which results in almost double processing capacity compared to using a wheel loader. In most secondary processing operations, such as material depots, harbours, power plants to mention few, it is recommended to use a wheel loader as carrier because the wheel loader brings ultimate mobility of the equipment on the site and it makes it possible to easily move the processing carrier from site to site.

The ALLU M Series attachment is able to screen and crush material that is between 1 – 4 in Moh scale. The softest material being talc. Good examples are also: oil shale, coal, bauxite, phosphate, lime stone, kaolin, dolomite, gypsum, rock salt, etc.

By applying the correct amount of crushing force the attachment separates, while crushing the soft material, any hard unwanted materials in the rock mass. This separation feature is called dry enrichment.

Oil Shale is a good example of where the dry enrichment feature brings lot of benefits to the mining operation. Oil shale deposits are found in layers together with lime stone which is mainly considered as waste. When processing oil shale with the M Series attachment, one can easily crush the soft oil shale and at the same time separate the harder lime stone in One Step. 

This dry enrichment of the rock mass results in higher energy value of the oil shale and the separated waste rock can be left in the mine. This separation feature brings big environmental benefits to the mining operation because the separated waste rock is never transported out from the mine.

For more information, visit www.allu.net

Video 1: ALLU has been the pioneer and inventor of the bucket type screener crusher attachments.

Video 2: ALLU M series has been specially developed for the soft rock mining sector and mining carriers.

How equipment manufacturers can deliver processing systems that are fit for purpose. Peter Craven reports.

A major challenge for mining equipment manufacturers in the years ahead will be to provide materials processing systems that are able to be efficiently deployed in increasingly remote locations.

There will also be a requirement to process increasingly difficult materials that have been overlooked until now. As our demand for steel, aluminium, copper and silica sands and other industrial minerals continues to increase mining companies are constantly looking for new and improved processing technologies that will allow them to process lower grade ores and industrial sands and produce final products suitable for use in downstream processes.

Another development we have witnessed is an increased focus on staged investment as a means of delivery for new mining projects – designing your plant in such a way as to allow for production to begin in the shortest possible timeframe while planning for further plant and process development. To use the age old adage ‘the customer is always right’, if mining companies are looking for equipment that can be more efficiently deployed, that can process increasingly difficult materials and that are is suitable for staged investment then it is the responsibility of equipment manufacturers to meet these requirements.

In looking at how we can do this I will look at a number of issues which can be categorised under these headings:

* Built with the application in mind;
* Modularity;
* Intelligent process integration;
* A phased approach to design and delivery;
* System adaptability;
* Mobility – without compromise;
* A turnkey approach. 

Built with the application in mind

Every project presents its own unique challenges. When we look at the raw material there are a several factors which will influence the selection of the appropriate processing system. The quality of the ore is the first issue to consider. In addition to this we need to analyse the level of contamination within the material that needs to be removed. This could be sticky plastic clay that requires a logwasher to provide the necessary attrition. In the case of iron ore processing we will also have to consider the levels of silica and alumina contamination which if they are not removed will lead to inefficiencies in downstream steel production processes. The presence of all of these materials necessitates that every project is considered as a stand-alone system and designed, specified and constructed individually with a full understanding of the requirements of the project.

If we take this to its logical conclusion the response from equipment manufacturers to this scenario should be to produce tailored processing systems for every individual project in order to maximise process efficiency. This represents a major shift from the typical business model for equipment manufacturers – which is to produce a limited range of standard machines that can be applied across a wide range of applications. Using standard machines presents a problem, and requires end users of the equipment to accept that they will have to compromise on performance, if they do not intend to run the equipment within the designed operating parameters.

While the vast majority of equipment manufacturers will tell you that tailoring each individual project is not possible – the reality is that it is entirely possible. Our experience in the mining sector has shown that there are a number of individual considerations that need to be made in order to maximise the efficiency of the final processing system.

The selection of the appropriate screening media is very important – polyurethane is almost always the best match for mining projects but not all polyurethane is equal. Due consideration must be given to the abrasiveness and specific gravity of the material to ensure that the most suitable product is specified.

The choice of lining for any hydrocyclones also requires individual consideration – rubber lining may well be suitable on some materials but others will demand ceramic linings when dealing with highly abrasive mineral ores.

Consideration should also be given to the requirement for additional wear liners at specific points in the system. Easily replaceable wear liners at the feed point will have a positive impact on plant availability by minimising the time required for maintenance.

The appropriate conveyor belt specification will also require individual treatment based on the nature of the material to be processed. Enhanced top cover thickness will enhance wear resistance, maximise plant productivity and reduce costs of operation through a reduction in the spare parts requirement. Staying with conveyors, the inclusion of belt cleaning systems such as tungsten tipped scraper blades will also offer enhanced wear resistance.

The specification of appropriate pumps is also critical in an effort to ensure they will stand up to the rigours of the material to be processed.

Modularity

A rise in the popularity of modular processing systems on mining projects has been evident over the last number of years. One of the major motivations for a move in this direction from our own perspective was a focus on Transfer Point Technology – ensuring the efficient transition of material from one stage of processing to another. The direct result of this approach is to maximise material retention within the circuit and avoid bottlenecks within the system where the discharge point from one processing phase is not optimised for seamless delivery to the next stage.

There are numerous advantages to this approach – greater process efficiency and reduced installation and commissioning time being the most obvious. All of this works together to ensure you are able to start extracting value from your material as quickly as possible.

In most, if not all mining projects there will be a requirement to integrate third party equipment within the processing system so it is also important that designers are aware of the likely connections that will need to be made and consider this very early on in the design process. This will streamline the project design process and ensure that once the system is up and running it operates at maximum efficiency.

The third party equipment that CDE has most experience with when designing processing systems for mining projects are attrition cells, spiral classifiers, decanter centrifuges and filter presses. Through the development of partnerships with suppliers of these systems we can ensure that our focus on Transfer Point Technology does not stop at our own products but extends to this thrid party equipment as well. As a result of our focus on tailoring each system we are also able to manage the introduction of new equipment to our systems as and when required.

Intelligent Process Integration

Intelligent Process Integration involves the introduction of several different processing phases onto a single chassis. Aligned with the previous point on modularity this allows for transfer point efficiency to be maximised. Additional advantages are a reduced plant footprint which results in a reduced civils requirement. These factors combine to reduce both the time required and the final cost of the project.

When feed systems, screening plant, fines processing, scrubbing systems are all provided as individual stand-alone units there will be a large amount of design time spent on designing civils and support structures to accommodate all of this equipment. Once the equipment reaches site the time taken to mechanically install the plant will be longer than necessary as a result of having to put all of the individual components together.

The reduction in mechanical install time is delivered because all equipment undergoes a complete pre-build to its working position in a factory environment. This is a final quality control step that allows for any fabrication issues to be addressed before equipment is dispatched. Our focus on the delivery of wet processing systems means that this approach extends to ensuring all pipework connections are already established prior to dispatch – eliminating the requirement for cutting or preparation work on site, reducing install time and eliminating the requirement to source this pipework locally either because it has been damaged in transit or is missing from the items delivered to site.

Another significant advantage of integrating several processes onto a single chassis is that all equipment can be pre-wired and tested in a factory environment. Adding to the reduction in time taken for mechanical install, the electrical installation time is also reduced. It also has the advantage of making the electrical connections a design feature of the plant – cable runs and housings are part of the design process which not only improves the aesthetics of the plant but also enhances health and safety on site.

This approach also reduces the requirement to try and find local suppliers of cables and other electrical items – particularly relevant in any discussion concerning how to approach mining projects in remote locations.

A phased approach to project delivery

Through a phased approach to project delivery it is possible to show a return on your investment much more quickly. The start of this process will be detailed discussions with your mining engineers to understand the specifics of the reserve – capacity requirements, likely requirements for future upgrades. This will also involve a detailed analysis of your material in an attempt to understand whether it is possible to kick start a project with a simple processing system which can then be added to as and when required.

For example, a detailed material analysis throughout the reserve will reveal whether there is a seam of relatively clean, uncontaminated material that requires minimal processing. Following this it can be determined at what stage additional equipment may be required – for example a logwasher may need to be introduced to tackle claybound material or to help in the removal of other contaminants. Following this a third phase may be the introduction of primary stage water treatment and tailings management systems.

From an operational perspective the main advantage of adopting a phased approach is that rather than waiting for months on the delivery of a complex processing system, most of which will be under-utilised for a period of time you are able to take delivery of your first phase equipment in as little as 12 weeks. This allows you to begin to show a return on the investment very quickly which helps fund the future expansion of the plant when conditions dictate that it is necessary.

System Adaptability

We have touched on the variability that is inevitable within mining projects and what is required at the outset may change over time. Future developments with your business may require a capacity upgrade to meet a rise in demand for the material you are producing. We may come across an area of your reserve with particularly challenging material that will require the introduction of a new process. Space restrictions on site or future environmental legislation may require the introduction of a tailings management system.

Given this potential for circumstances to change, it is essential that your processing system has the in-built flexibility to respond to these changes. We can’t predict the future but through a comprehensive analysis of your material we can identify whether for example there is likely to be a requirement for an additional process to be introduced and when this is likely to happen given your extraction plan for the reserve.

If we have established that your business plan indicates a likely requirement for additional capacity as extraction progresses we will design the civils on site to take this into account – minimising disruption to your operation. We will also bear this in mind when considering the location of the processing plant in the first instance to ensure that once any upgrade is required the original location is still suitable. Another step that we will take is to ensure that the original conveyor specification is fit to cope with the forecasted additional capacity both in terms of belt specification and stockpile capacity.

Similarly, if additional processing equipment is likely to be required this can be considered during the design of the original plant civils. We will also conduct a detailed analysis of the likely future water and power requirement once the additional equipment has been added to make sure that this infrastructure is in place.

Mobility without compromise

Mobile makes sense. As your extraction progresses it makes sense that your processing plant should be able to be moved within the deposit to ensure maximum operational efficiencies are delivered. With a static processing plant this is not possible. As your extraction progresses your operational efficiency is reduced – increased transport movements on site as vehicles have to haul material greater distances to the processing plant, unnecessary double handling of your material as it is stockpiled at the extraction point before being delivered to the processing plant. By opting for modular equipment which integrates several processes on a single, easily transportable chassis you ensure that your processing plant can be moved quickly and easily within the deposit – or to another processing location – in order to maximise operational efficiencies.

This should be done without compromising on the specification of the screens, fines washing plants or logwashers that are included. The creation of a modular product range fit for purpose in mining projects should involve the same specification of equipment as would be included on a static plant.

One of the major areas of compromise on mobile plant is with the walkways – ladders leading to very narrow walkways are the norm on most mobile machines. This makes plant maintenance very awkward, – increasing the time and therefore the cost of carrying out plant maintenance.  Site health and safety rules may also be compromised.

This is why we believe that even on mobile or portable plant the walkways for access and maintenance should be of the same specification as would be found on a static plant. This ensures that you continue to enjoy all the benefits of a static plant in relation to maintenance access – ease of visual inspection, access to change screen media ,media, replace spray bars, and  carryand carry out hydrocyclone maintenance.

The issue of maintenance access is often overlooked when a processing plant is being specified but it is a very important consideration as it is a factor which will have considerable influence on plant availability and delivering the highest standards of health and safety on site.

A turnkey approach

It is evident from the analysis of all the aspects that make up a successful mining project in the 21st century that a much greater level of interaction between equipment manufacturer and the  end user is required in order to deliver successful projects. With the many considerations that need to be made there is potential for a huge number of vendors to be involved on each and every project and this requires that a robust Project Management system is in place.

Our own process is split into three distinct phases:

* Technical Pre-Sales;

* ProMan;

* CustomCare.

Each of these phases include large amount of work. In Technical Pre-Sales the elements include process design, equipment selection, mechanical design, civil design and third party equipment integration. As we move into the delivery phase of the project ProMan takes over and includes factory testing, power distribution, risk management, scheduling, budget management, construction management and quality control. Once your plant has been successfully installed and commissioned our range of After-Sales services are activated including our MasterClass training programmes, service visits, recommended spare parts lists and on-going maintenance contracts.

The effect of being able to offer this complete range of services in addition to the equipment that we provide is to significantly reduce the number of vendors involved in the project, the result of which is a more streamlined project timeline which costs less to deliver. Effective communication is crucial to the delivery of successful materials processing projects and our process provides you with a dedicated single point of contact throughout the project lifecycle to ensure you remain fully informed at every stage of the project. Another advantage of this approach is that it helps to develop both our knowledge of your business and your knowledge of our capability which will allow both parties to explore the potential for further co-operation in the future.

In Conclusion

It is clear to all involved in the delivery of mining projects in the 21st century that there are many complex issues to overcome. The demands of the industry are constantly evolving and it is essential that the products offered by equipment manufacturers continue to evolve. It is equally important that equipment manufacturers develop their processes and approach to project delivery in order to continue to meet the demands of the industry.

In summary, I believe there are three main considerations in this analysis of how equipment manufacturers can continue to supply mineral processing systems that are fit for purpose.

1. The individual components that make up a complete processing plant cannot be looked at in isolation and should instead be made up of modular systems with the in-built flexibility to cope with shifts and changes in individual project circumstances.

2. Off-the-shelf processing systems from a collection of different manufacturers will not deliver the efficiency required of 21st century mining projects. A tailored approach is required with each individual project being built according to the specific requirements of the project – capacity, feed material and potential for future development.

3.  Equipment manufacturers must get closer to the project and the end-user and understand the background, the specific objectives and the plans for future development. For most equipment manufacturers this requires a huge shift in the way their business models are constructed. 

Peter Craven is with CDE Global Ltd.

Anesco is to undertake a major regeneration of a number of Harworth Estates' former colliery sites with the development of a 30MW solar portfolio - falling strongly in line with Government strategy to develop solar on brownfield land.

The ground-mounted solar installations will be operational for 25 years and, once completed, will generate enough low-carbon energy to provide power for around 10,000 homes, while saving up to 15 tonnes of carbon per year.

The project will begin with the development of three sites in Nottinghamshire: Welbeck Colliery in Mansfield, Gedling in Lambley and a third site in Bilsthorpe. A fourth site at Askern in South Yorkshire is awaiting planning consent.

Anesco is working with landowner Harworth Estates, the UK property regeneration company, in bringing forward construction work at Welbeck, with work expected to commence on the remaining sites later in the year.

Adrian Pike, CEO of Anesco, said: "Working with landowners to develop sites likes these former collieries fits perfectly with government policy, with the Department of Energy and Climate Change pushing the focus of growth in solar to be on brownfield sites and domestic and industrial roofs. These sites are based in the Midlands and north of England, which is important as we believe it is essential that solar developments are made across the UK and not just in the south west.

"Through these installations we will not only be regenerating disused land but will be creating employment, generating renewable energy and helping to reduce the UK's carbon emissions," he added.

Eddie Peat, director of Natural Resources at Harworth Estates, said: "Low-carbon energy projects are an important part of Harworth Estates' commitment to the community and the environment, and our solar projects with Anesco will deliver both energy for thousands of new homes and new jobs for the region."

Welbeck Colliery in Mansfield will be the first site to come online. The installation will cover an area of almost 32 acres and will generate carbon savings of around 5.11 tonnes per year. It will comprise of 44,160 solar panels mounted on around 15km of frames that have a combined generation capacity of 11.2MW - sufficient energy to power more than 3,450 homes in the local area.

This will be followed by 5.74MW installations at both Gedling and Bilsthorpe, and an installation currently in the planning stage for Askern. Once active, each solar farm will be monitored by Anesco's maintenance system AnescoMeter which will ensure they continue to operate at their optimal capacity.

Nippon Dragon Resources is pleased to provide summary information regarding its thermal fragmentation activities in Southern Africa with its distributor MaXem Equipment. As publicly announced by way of a press release on February 25th, 2014, Nippon and MaXem entered into an exclusive thermal fragmentation distributorship agreement for various South African countries. In May 2014, a thermal fragmentation unit (Dragon) was delivered to MaXem’s facilities, followed by Nippon’s employees, whose mandate was to train MaXem’s employees and also visit the mine site where the first deployment of the technology in South Africa would take place.

In early June, Nippon’s team returned to South Africa to present the technology to potential clients, including one of the most predominant gold producers in the world. Over the following days a series of performance, security tests and demonstrations were conducted for the benefit of several decision makers and union representatives. The Dragon has since been deployed within the stope (work area) approximately 1,000m below surface on a demonstration contract and thermal fragmentation operations began on July 3rd, 2014.

“Operating in a reef type ore body was something new for us and the Dragon performed extremely well fragmenting its first hole in South Africa. We do not foresee any technical difficulties with regards to fragmenting the type rock and the dip encountered in the ore body,” stated Donald Brisebois, Nippon’s VP operations and technology.

MaXem is a multifaceted company, whose core business is to supply hard rock mining equipment and services to Southern Africa countries, with a specific focus on precision long hole drilling and other methods that enable better efficiency in mining. MaXem contracting includes long hole drilling, drop and inverse raising and mechanised mine production. MaXem has a clear understanding of mining inherent risks as well as detailed commodity experience that includes gold, platinum, heavy minerals and base metals.
 
Nippon is active in the exploration and the development of gold resources in Quebec and Peru. The corporation holds a gold property with resources recognised in accordance with NI43-101, a modular treatment plant and also an exclusive license for the thermal fragmentation mining method for exploiting narrow-vein ore deposits.
 

As China aims to improve its coal mine safety record, it is investing in new, large-scale mining operations with modern equipment, while also improving the safety and productivity of the medium sized enterprises. In order to assist this initiative, RMI has launched a range of high pressure pump stations which are designed to provide a cost effective pumping system; predominantly used for powering the roof support systems.

RMI Pressure Systems has been involved with the Chinese coal mining industry for 30 years, installing high pressure pumping systems in over 10 provinces across China. It has also established a sales and service network designed to provide extensive product support to this important market. With safety and reliability being improved, especially in the largest mines, attention is now being focussed on the smaller mines.

Streamline range of pump stations developed for the second tier mines

The new Streamline range of pump stations has been developed specifically for the second tier mines and has been created using a standard product offering. This approach has allowed RMI to increase the scale of production, and therefore reduce the manufacturing costs for the range without reducing any of the safety and reliability factors.

Based around its S range of pumps, RMI has developed six models in the Streamline range; three for emulsion systems and three for water systems. Renowned for producing one of the most reliable reciprocating pumps in the mining industry, RMI has maintained its focus on material selection and machining tolerances which ensure it continues to deliver high efficiency and excellent reliability.

The emulsion systems are supplied with three S375 pumps, which operate as duty, assist and standby and are supplied by two tanks. The water systems operate with two S300 pumps, on a duty / standby arrangement, and come with one supply tank. Both systems are controlled by the same, well proven, technology which is found on the existing range of larger pumping stations.

With a net power rating of 405 horsepower (302kW) and a maximum operating weight of 74,966 pounds (34 004 kg), the Cat 824K Wheel Dozer is available with six blade configurations ranging in capacity from 6.6 to 21.1 yd3 (5.0 to 16.2 m3) to customise it for production dozing, stockpile dozing or cleanup work.

The Cat C15 ACERT engine features an electronically controlled fuel delivery system, an engine idle shutdown system to conserve fuel by limiting idling time, and a delayed shutdown feature to ensure that the engine is not stopped until operating temperatures have stabiliszed. 

Drive train efficiency, fuel economy and travel speeds are further enhanced with the lock-up clutch in the Cat torque converter, a feature that reduces both drive train power losses and system heat. 

Two engine options are available that meet either U.S. EPA Tier 4 Final/EU Stage IV emission standards or U.S. EPA Tier 3/EU Stage IIIA equivalent emission standards.

For further drive train efficiency, the smooth-shifting, electronically controlled, 4F/4R Cat power shift transmission can be set by the operator to automatically upshift or downshift based on machine speed. In addition, the Single Clutch Speed Shifting controls allow the 824K to carry momentum through range shifts for high productivity and fuel savings.

Both operating efficiency and operator convenience get a boost with the left foot pedal, which serves as an engine decelerator, transmission neutraliser and brake, depending on the degree of application. As a decelerator, the left pedal allows the operator to temporarily reduce engine speed by overriding the throttle lock setting when manoeuvering around obstacles. Additionally, a new fuel tank provides minimum 12 hours operation, depending on the application.  An optional tire pressure monitoring system provides real time information to the operator in the cab, ensuring proper inflation and optimising tire life. 

The STIC (Steering and Transmission Integrated Control) system allows single-lever steering and transmission control. Simple side-to-side movements of the STIC lever provide up to 43 degrees of steering articulation in both directions for precise manoeuverability, and buttons on the lever provide fingertip control of directional and range shifting.

A primary focus for the 824K design is operator convenience and safety, such as providing lighted, shallow-angle stairways for entering and exiting the cab and designing the STIC armrest to fold away for added room when entering or leaving the seat. Also, the Cat Comfort Series air-suspension seat features extra thick cushions and moves both the attached electro-hydraulic STIC control pod and electro-hydraulic implement control pod when adjusted. 

The cab, isolation-mounted to the frame, is pressurised with filtered air, and the selected temperature is maintained automatically. The control panel uses large, backlit switches with LED indicators, and a simple two-position rocker switch controls the parking brake. An optional rearview camera with in-cab monitor increases operator awareness.

As newly released statistics illustrate the continuing imbalance of women in science and engineering professions, leaders of 20 of the UK’s science, technology, engineering and manufacturing companies have written to the Prime Minister, seeking his support for a new industry-led campaign to boost the retention and development of women employees.

Data published today by WISE show that, although the number of women engineering professionals has doubled since 2012, they continue to represent less than 10% of the workforce - the lowest proportion in Europe. To reach even a modest target of 30%, WISE calculates that the UK would need 1 million additional women in the science, technology and engineering workforce.

To address this challenge, 20 major UK companies have committed to a 10 point plan, based on actions which have proved to make the most difference within a science, technology or engineering environment. The ten steps have been developed by industry members and partners of the Royal Academy of Engineering and the WISE Campaign. 

Trudy Norris-Grey, Chair of the WISE Campaign, said: “Our economy needs more women in science, technology and engineering to propel the competitiveness of UK industry on the world stage. To make a real difference, we need the commitment of industry at the highest level to ensure the working environment gives women the same opportunities to succeed as their male colleagues.

“I am delighted that 20 top companies have shown leadership in being the first to commit to implement the ten point plan.  We hope that, with the Prime Minister’s support, many more companies will join them in the future.”

The campaign is already gaining momentum in the highways sector, as Highways Agency Chief Executive Graham Dalton has made a personal commitment to sign as well as to promote the Ten Steps within their supply chain. 

Allan Cook, Chair of the Academy’s Diversity Leadership Group and Chairman of Atkins, commented: “UK industry needs to recruit, retain and inspire the best talent available to build and retain a competitive position in the STEM business sector.  As long as women represent such a small proportion of our workforce, especially at senior levels, we know that we are missing out on a rich pool of talent. It is widely recognised that a diverse workforce offers real advantages in terms of increased innovation and effectiveness.”  

“This is a business imperative as we look to maintain and enhance the UK’s competitive edge in our engineering sector which is such a vital part of our national economy.”

The 10 point plan is a pledge to:

* Understand the starting point and put plans in place to improve performance and monitor progress;

* Educate leaders and give them accountability for change;

* Change mind-sets by challenging bias and sexism;

* Be creative in job design;

* Make flexible working a reality for all;

* Increase transparency of opportunities for progression;

* Sponsor talented women, giving the same exposure as men and support to develop their career; 

* Demonstrate to women that we want to retain them through career breaks and beyond;

* Treat the retention of women as we would any other issue affecting our core business;

* Share learning and good practice with our industry partners. 

The 20 business signatories are:

Robin Southwell - President, Airbus Group UK; Uwe Krueger - Chief Executive, Atkins; Alan Belfield - Regional Director, Arup; Peter Rogers - Chief Executive, Babcock; Ian King - Chief Executive, BAE Systems; Christine Hodgson - Chairman, Cap Gemini; Bob Joyce - Director Product Creation and Delivery, Jaguar Land Rover; John Lazar - Chief Executive, Metaswitch; Grant Rumbles - Chief Executive, Mouchel Group; Steve Holliday - Chief Executive, National Grid; Mark Carne - Chief Executive, Network Rail;
Colin Lawther - Senior Vice President, Nissan; Steve Reffitt - Chief Operating Officer, Parsons Brinckerhoff; Ian Powell - Chairman, PWC; Leo Quinn - Chief Executive, Qinetiq; Ian Davis - Chairman, Rolls-Royce; Liv Garfield - Chief Executive, Severn Trent; Erik Bonino - Chairman, Shell UK Ltd; Victor Chavez - Chief Executive, Thales UK; John Neill - Chair and Group Chief Executive, Unipart.

A surface treatment provides superior corrosion resistance for chain and sprockets used in ultra tough conditions

As the extraction and processing of the raw material is done in the most demanding of environments, components on the machinery in these applications need to excel in tough conditions. 

For surface mining Tsubaki offers a wide variety of tried and tested heavy duty roller chains, conveyor chains, reclaimer chains, engineering class sprockets, back stops, electro mechanic actuators and protection devices for use on equipment or in plants such as drill rigs, feeder breakers, rotary breakers, mining shovels and conveyors.

* Underground mining: In this extreme environment shock loads are high and chain and/or sprocket failures can take hours to repair. Thus, efficient and reliable extraction can mean the difference between profit or loss. In this environment, all the equipment must be as reliable as possible and provide maximum performance with minimal downtime. For these harsh applications Tsubaki offers its specially designed shuttle car chains, heavy duty chains, and chains for continuous miners.

* Speciality mining products: Tsubaki has also designed and manufactured its own line of top-grade carbon steel, alloy, and stainless steel sprockets for use with its chains to maximise reliability in mining applications. It has developed a series of Back Stops, Cam Clutches and Power Lock devices which can be utilised in various applications and industries to help improve safety on the mining site. Cam Clutches and Back Stops allow freewheeling or overrunning in one direction, and driving or backstopping in the other, protecting both the equipment and employees, while Power Locks eliminate backlash damage to keyways from heavy loads.

Tsubaki has developed a surface treatment for its chain and sprockets that provides superior corrosion resistance and significantly extends the service life of the components.  The mechanical plating system forms a lasting bond to the steel and is recommended for use on any equipment that may be exposed to external conditions, chemicals or salt water.

Hydraulic roof support systems are critical to longwall mining and to the safety of the miners

The practice of longwall mining has been developed and refined with the use of hydraulic roof support systems, which provide support at the coalface to allow the shearer to cut the coal from the seam. Each support can weigh 30-40 tonnes and be rated at 1000-1750 tonnes and also have the ability to hydraulically advance itself one metre at a time.

As the roof supports advance, so the roof of the mine is allowed to collapse behind them and the shearer continues to pull the coal from the seam. This all makes the roof support system of critical importance to the mining operation and to the safety of the miners involved in operating the machinery. Any equipment which is selected to operate in this hazardous environment must be proven in reliability and require a minimum level of maintenance.

The efficient operation of the roof support system directly affects the productivity of the mine and any down-time on the system in such a difficult operating environment would be very counter-productive. The reliable performance of these systems is essential if the client is to maximise output from the mine and return on investment.

The Kopex group, a supplier of mining equipment and technology, is delivering a turnkey solution for the Vladimirskaya longwall coal mine in Russia. Part of this project is the powered roof support system to be installed at the coalface itself. Kopex has awarded the supply of the critical pumping systems to RMI Pressure Systems Ltd, Manchester, UK.

The roof support systems require a power source and this takes the form of a sophisticated hydraulic pump capable of producing extremely high pressures. The reliability of these pumps must also be beyond any doubt and bench testing has to be carried out for thousands of hours to ensure their operation in the mine will be faultless. In this case, Kopex has selected RMI Pressure Systems, which has a proven track record in the mining industry and has considerable experience in supplying equipment for the longwall mining operation.

RMI has delivered three Trimax S300 pumps to power the roof support system, each capable of providing 244 litres/min at up to 353 bar, as well as two of Trimax S300 pumps for the water pumping system, which are cable of providing 319 litres/min at up to 92 bar. The entire contract also includes a service and spares package as well to ensure continued reliable service.

In 2012, the Russian government approved a long-term investment plan for the coal industry, with $123 billion to be invested over the next 17 years. This is deemed necessary to meet the future requirements for coal which is used to generate 25% of the electricity requirement in Russia. Coal production from the underground mines is expected to increase by nearly 50% over the next 20 years.

Scaling involves the removal of dangerous, hanging rocks before they fall due to some unplanned action. Maurice Jones reports

Falls of ground underground continue to feature in most sets of underground mining safety statistics. The term suggests, often wrongly, a major collapse of roof or sides but falls of individual but heavy, loose boulder or cobbles from a hanging position can equally cause death or major injury to anyone in the vicinity.

Scaling involves the removal of dangerous, hanging rocks before they fall due to some unplanned action. Much depends on the type and condition of the rock being worked. As examples sandstone beds can produce large blocks from the roof, whereas shaley ground is often more friable with the possibility of large falls of much smaller but also hazardous lumps.

Even in open-cut mining, scaling may be required particularly on high walls if they are expected to stand without further excavation for a considerable time.

The other causal factor is the effect of blasting in which accuracy of peripheral cut holes may be important for safety, if not for production, and overcharging should be avoided for safety as well as economy.

The best, and most widely adopted, strategy against smaller falls of ground is a systematic approach to removing the hazard, as soon as possible after a blast. Primarily none should enter a hazardous area before it is made safe.

Traditionally scaling has been a manual practice using crowbars or specially designed scaling bars such as the range available from DSI (Dywidag-System International). These features moil or chisel points with solid steel, tube steel or aluminium bodies. Access and reach may often be problems; best carrying it out from a properly designed access basket starting from the last ‘permanently’ supported area and approaching the face one reach length at a time.

Introduction of mechanised scaling makes it easier to adopt a systematic, and thus safer, approach to task, with improved speed to make it less laborious and improve overall mining efficiency.

While standard designs of hydraulic, and sometime pneumatic, breakers are used for scaling usually mounted on an hydraulic excavator, the particular stresses of the task call for specially designed tools that can better stand the additional forces, and sometimes abuse, involved in the task. Intermittent scaling needs may allow the use of more standard breakers, such as may be used for face excavation, if the likely increased maintenance can be tolerated.

Atlas Copco’s range of breakers includes scaler versions of the SB 302 and SB 452 ‘Solid Body’ breakers. The latest generation, introduced in 2010, has a higher blow frequency, with an automatic decrease if the tool is not pressed hard on the surface, thus decreasing unnecessary vibrations. A water channel for dust suppression, and automatic lubrication channel are housed within the breaker body for protection against falling rock allows you to spray water to reduce dust levels.

The same manufacturer’s dedicated mining scalers, a series of four models of Scaletec rig plus diesel-hydraulic versions, are enjoying increasing sales interest amongst mines wishing to step up both productivity and safety. New Boliden’s Tara Mines (the largest European zinc mine) in Ireland has been using Scaletecs since 2007 for routine scaling after every development blast. The rig allows the operator to work in a protected cab well back from potential falling rocks, and a dozer blade aids in clearing the worksite after scaling. Models LC and MC include the Atlas Copco Rig Control System for accurate boom positioning.

Rammer, part of Sandvik, offers a range of three scaler (breakers specially designed for scaling); the 555, 777 and 999.

Gradall Industries offers scaling versions of it’s wheeled excavators employing its rugged, two-piece telescoping, triangular boom and hooked breaker for maximum leverage to further loosen hazardous rocks.  The units are widely used in limestone mines in which the comparatively low profile of the excavators and boom mechanism allow easy operation under 6m headroom.

A possible way of avoiding scaling as a mining task which is, after all, largely non-productive, is to improve the accuracy of drilling and blasting so that hanging rocks do not remain after a blast. In mining accurate blasting is not often as important as it in ‘civils’ tunnelling, but this approach may benefit for permanent development and transport drives. A careful comparative study would be required to determine whether the increased cost of more sophisticated drill jumbos, probably with computerised control, and increased numbers of peripheral blastholes, can be justified over the best scaling procedures and equipment.

Another avoidance procedure, if the ground is suitable, is to use a fully mechanised mining method such as a roadheader or continuous miner, cutting the required profile. 

Videos 1: Atlas Copco presents: Scaletec: - Introduction to Atlas Copco’s Scaletec mechanised scaling rig and its operation

Video 2: DVD585 of 1996 by PublicResourcesOrg – Scaling produced by US Mine Safety and Health Administration describing safe scaling procedures, both manual and mechanised

Video 3: Gradall Excavators’ XL 4310 Series III model in use for scaling at Sidwell Materials’ new limestone mine in Zanesville, Ohio  

The Western Australian economy is diversifying but mining and oil still dominate. Maurice Jones reports

Everything about Western Australia and its mining industry is big including its importance to the whole of Australia, its widespread, largely unpopulated desert, the 15-mine Pilbara complex,

The history of mining in Western Australia (WA) is long, from the discovery of gold at Fly Flat in 1892 and Kalgoorlie the following year, but it was the demand for steel from the industrialisation of Asia, first Japan and then China and India, that promoted the exploitation of iron ore deposits that were thought to be limited until development of the Pilbara Craton and elsewhere from the 1960s.

In 2013 minerals and energy exports accounted for 91% of all the state’s merchandise exports by value. Minerals output was valued at AU$ 89 082M (US$ 81064.6M) of which AU$ 68 071M  (US$ 61 944.6M) was for iron ore and AU$ 8710M (US$ 7926.1M) for gold. Mining composed 37% of WA’s Gross State Product.

Despite political wrangling the importance of mining is recognised to the extent that, in an annual study by the Fraser Institute of Canada, Western Australia is the most favourably regarded administrations for investment attractiveness to the mining industry, and in the top ten in the Policy Perception Index. This was based on a survey of 4100 senior mining executives.

Other mineral commodities produced in Western Australia include, in approximate order or importance alumina from bauxite (AUD4117M), nickel (AUD3398M), copper, lead, salt (evaporated), cobalt, diamonds and coal, plus mineral sands and, later, uranium.

The industry is supported, in academic and research terms, by the Western Australia School of Mines at Curtin University, based in the state Capital of Perth on the coast and the established inland mining city of Kalgoorlie.

The importance of extractive industries to Western Australia, and Australia as a whole, has attracted frequent attention, often unwelcome, in terms of politics, taxation, environmental campaigning and social engineering. With reduced demand from China the industry is now faced with how it can keep going at a profit. Some smaller mining operations have already given up and closed down, and even the State is selling some assets to retain its credit rating in the downturn.

So what does this all mean in mining engineering terms? Most, and particularly the larger operators, appear to have decided that the only way is to invest in improved efficiency. If investment is not available, as is often the case with smaller projects, then the only path is the tried and tested one of cutbacks and making capital plant last longer, such as with improved maintenance regimes.

Investment projects, as undertaken by BHP Billiton, Rio Tinto, and Roy Hill Resources are featuring widespread use of remote control at many levels, both in underground and surface mining, including the total removal of operators from the work-site. Even the operational centres are not at the mines but at control rooms at Perth airports. Far remote-control of plant is another matter of intensive social comment, especially with regard to whether the main reason is to improve safety, as is usually stated, or just to reduce costs. Even without the mine social infrastructure avoided by fly-in, fly-out (FIFO) operations, the savings achievable by eliminating many operators are very significant (around $150 000 a year per head plus overheads we understand).

Other benefits of remote control of trucks and similar vehicles, and also drill-rigs, include consistent operational cycles, reducing the number of unpredictable incidents due to human error and other behaviour such as fatigue.

Another frequent theme about plant investment, particularly in trucks and some other vehicles, is the replacement of diesel drives with electric. This gains environmental care kudos but also has the potential for reduced maintenance and fuel delivery costs.

Video:  Good overview of Western Australian mining industry but produced before the recent downturn in demand. By John Digispyeu

Maurice Jones examines the latest developments in borehole surveying

Borehole surveying has had a long history of mainly steady development due largely to the demands of the upstream oil and gas industry where the stakes are high, including the available investment for the right methods. 

National geological surveys have also played their part, with the emphases on ‘pure’ research and the mapping of a state’s mineral and water resources.

Similarly the mining industry is naturally interested in potential reserves, although perhaps on a smaller and more detailed scale. The industry is also interested in using well monitored boreholes to find out about geological structures that may disrupt mining plans, groundwater to be used or avoided, and perhaps voids due to older mine workings and natural processes.

The ever-present pressure on costs means that it is important to reduce the time taken for drilling, monitoring, data collection and analysis of results if possible. Thus cutting the time taken for procedures is a spur to development.

Reflex (Tidex group) recently introduced a rapid descent version of the Reflex ACT digital core orientation instrumentation package with the ACT III RD. Subject to the condition of the bottom hole assembly it is claimed to be accurate to 88 degrees. It is waterproof and shock-tolerant and is easily maintained.

The drive for rapid data collection to save time and avoid drilling errors can be aided by Measurement While Drilling procedures, also sometimes known as Logging While Drilling (LWD). Much depends on the type of data required, the instrumentation that can be installed in the bottom-hole-assembly of the drill-string, and cross-interference that may occur between system and other drilling equipment. 

Scientific Drilling of the US and worldwide offers MWD services based on the use of mud pulse, electromagnetic and gyro devices. The company emphasises reliability with its TUF (Tool Utilization Factor) system to accumulate data on tool wear based on temperature and vibration levels (directionally logged) down the hole. The customer should then be able to achieve longer drill components life.

Devico of Norway offers a range of borehole logging and instrumentation systems with the emphasis on coring by directional drilling and multi-shot instruments. The use of accurate directional drilling from a single rig set-up can greatly save of exploration time and produce related data across variable-shape orebodies and other deposits from fewer locations. 

The Devico DeviShot multi-shot borehole survey instrument can record inclination, azimuth, too-face position, gravity vector, magnetic field vector and magnetic dip as well as the temperature and battery status. It comes with its own flexible DeviSoft .

Renishaw of the UK produces a number of borehole logging tools including the Boretrack. It is also marketing the C-ALS, which is a laser scanner deployable from a borehole to check on the presence and size of concealed voids to cut out the guesswork when one is encountered by drilling.  It is claimed to be the only such borehole deployable device on the market and is more accurate than alternatives such as ground-penetrating radar.

The processing of data collected, whatever its accuracy, can be a time-consuming and therefore expensive task. EpiLog from K&A Epimetron is an exploratory works management service that allows the user to enter, process and monitor many works in real time via the Internet. 

The main advantages of this procedure are immediate recording and management of drilling data, monitoring of works progress anywhere at any time, automated and immediate computation of quantitative data and a great reduction in the time required to produce reports and other documents. Results include valuable additions to exploratory data, better structural safety for mine workers and more accurate estimation of remedial measure requirements.

Vigilance is essential to prevent all possible mine explosions. Maurice Jones reports

The explosion (or fire depending on which reports you believe) at Soma coal mine in Turkey, in which 302 miners lost their lives, comes as a reminder to mining engineers, if any were needed, of the continued hazards in mining, particularly of coal.

Turkey, it is reported, now has the unenviable distinction of the worst safety record in coal mining in terms of deaths per ton of coal mined. Even if the validity of this means of measurement can be questioned, it does demonstrate both the huge production, and safety improvements in China where largely under-reported explosions and fires have claimed many lives. A China government policy to close smaller, largely uncontrolled collieries in favour of more efficient, and more easily monitored, large mines may be paying off in safety terms.

In recent years mining explosions with large loss of life have also occurred in Australia, India, Japan, New Zealand, Rhodesia/Zimbabwe, Russia, South Africa, Ukraine, and the US, so no one can afford to be complacent.

Those disasters that have been investigated independently have shown that the primary causes are dominated by failures of owners and management, sometimes with outside inspectors, to implement best practice in explosion prevention. The often simple technology, as well as known good practice, have been available for many years, and just require implementation and maintenance. There have been developments in such technology, chiefly in gas monitoring, communications and for the preservation of life once an incident has occurred, but not offering the degree of safety improvement that good management could achieve.

Basically an explosion requires the three participants of fuel, oxygen and ignition to occur, and an enclosed space to promote the explosion. The fuel and oxygen must also be present in the correct proportions to form an explosive mixture. Prevention can be achieved by removal of any one of these from the source. Removal of oxygen is largely impractical except in extreme circumstances when an area has to be sealed off.

Dealing with atmospheric explosions rather than the less likely possibilities of blasting explosives misfires, liquid fuel explosions or battery hydrogen ignition, the fuel in mining usually consists of mainly methane (not exclusively in coal mines) or coal dust. Methane, or ‘firedamp’ mixture, can be removed by adequate ventilation, not forgetting that the low density of methane can cause the formation of roof layering in some circumstances. Although this will introduce oxygen the ventilation must be sufficient to lower the proportion of methane to below its lower explosive limit.

Although the danger of coal dust has long been recognised in propagating an explosion probably starting with methane, the possibility for explosions involving only coal dust in atmospheric suspension took a lot longer to be recognised. Even so UK text books in the 1950s referred to this danger. The increase of mechanisation has led to the creation of more fine coal dust making this fuel an increasing hazard through both explosions and inhalation to miners’ lungs. 

Coal dust can be dealt with successfully by removal by extraction ventilation and air scrubbing, suppression with water mists at source, and/or clearing up accumulations by manual means. Water barriers have also been tested, but are less effective unless a spray on the flame can be assured to dissipate the cooling effect.

Although active barriers, triggered by flame or heat detectors to apply water or special chemical fire extinguishers have been tested for effectiveness and practicality, they have not shown to be substantially more effective than passive stone-dust barriers in mining. 

Sources of ignition resulting in explosions can vary from open flames, through high temperature surfaces to sparks from mechanical action and electrical arcing. Equipment capable of creating a hot enough arc flash must be housed in strong flameproof enclosures to prevent the ignition of any methane in the enclosure from spreading out to the general atmosphere, and to retain any explosion.

Another common and troublesome source of ignition can be the spontaneous combustion of volatile coals through passage through the mass, usually fractured in some way. Improved ventilation to remove firedamp could actually increase danger without attention to adequate sealing. Side effects can include the generation of poisonous carbon monoxide and even hydrogen from any water applied to such a fire. 

Video: This video is based on one produced by the US  MSHA following the Framington coal mine explosion in West Virginia in 1968

The extraction and processing of minerals takes place every day on every continent. Every day mining companies need reliable pumps for a wide range of diverse and challenging applications. 

Positive displacement pumps from Netzsch have been used for six decades to guarantee process reliability. A great variety of media must be conveyed, including wastewater, mineral slurries, suspensions, filtrates, tailings and explosives, all of which can be reliably handled by Netzsch pumps.

NEMO progressive cavity pumps are suited to the transport of abrasive and viscous substances. With NEMO pumps and TORNADO rotary lobe pumps, Netzsch offers an engineered solution for every application and ensures dependable, efficient operation.

The company is taking part in the following exhibitions:

* Maden Türkiye 2014 from 27th November to 30th November 2014 in Istanbul (Turkey);

* The BTA 2015 Barcelona Tecno Alimentaria from 21st April to 25th April 2014 in Barcelona, Spain;

A free admission ticket voucher is available from the Netzsch.

Netzsch Pumps & Systems has production plants and sales offices on all continents. Technical experts give individual advice and offer tailored concepts and competent after-sales service.

NETZSCH Pumpen & Systeme GmbH is based in Waldkraiburg, Germany.

Emissions legislation is placing the focus on clean diesel upstream of the distribution channel

Environmental legislation means that mining haulers and equipment from the likes of Caterpillar, Liebner, Komatsu and many others to be used in the USA and in Europe will be subject to higher emission standards for the type of particulates coming from their exhaust.

To meet Tier 4 Final (USA) and Stage IV (Europe) requirements, engine manufacturers have produced new engines but they will require cleaner fuel from the point of receiving it through to dispensing it. The precision of today’s diesel engines turns development focus on filtration technology further up the distribution channel.

Using clean and on-specification diesel fuel ensures extended equipment uptime, reduces costly repairs and keeps warranty claims to a minimum. With the latest exhaust emission mandates, clean fuel has taken on a whole new importance. 

Visual inspection of fuel during filling is no longer adequate and reliable. The smallest particle the eye can see is approximately 40 microns wide. 

That’s when Parker Velcon is called in to help design bulk fuel filtration systems that will ensure clean diesel throughout the fuel delivery stream. First, the company’s sensor technologies can help customers determine what types of contaminants are present. Second, appropriate Clean Diesel high-flow, high-capacity fuel filter/water separators and filters are recommended to pre-treat the fuel upstream at delivery, transfer and dispensing operations.

There is a real need to provide more pre-filtration steps. When the fuel leaves the refinery it is generally clean. Nevertheless, each time the fuel is moved it picks up tank residue. Even the air drawn into the tanks contains enough airborne dust and moisture to cause extensive damage. Every transfer point between the refinery and the actual point of use can add contaminants to the fuel. This is more frequent in remote applications such as in Australia and Africa because of the many transfer points required to deliver the fuel. Different climate conditions add to the challenge by creating water in the fuel tanks that promotes rust and algae contamination. 

Equipment operators can take matters into their own hands and many have. The Diesel Filtration Skid from Parker Velcon combines particulate filtration with water coalescing technology to handle flow rates up to 3955 gpm. Fuel monitoring options include the Velcon Contaminant Analyser (VCA), which is engineered to provide real-time, simultaneous detection of both water and particulate contaminants in diesel delivery systems at full-flow conditions. Two separate sensor technologies consistently differentiate between water and solid contaminants, analyses the contents of flowing fuel in a pipeline 600 times per second and produces an averaged result every two seconds in parts per million (ppm) and ISO 4406 codes. The company also offers other analysers for lower flow rates (IPM, icounACM20, etc.) and fuel farm laboratories.

Cronan Connell looks at how energy absorbing rubber liners reduce metal fatigue and stress fracture

Valley Rubber’s Haul Truck Liners reduce maintenance and provide increased equipment availability.

The exceptionally strong rubber liner system virtually eliminates costly continual box maintenance and helps prevent excess wear to critical components.

When properly designed for the application, the rubber liner system is superior to conventional steel liners. Energy absorbing rubber liners reduce metal fatigue and stress fractures to the box.

In addition, driver safety and comfort is enhanced, both from reduced shock, as well as substantially reducing noise. The fast and easy-to-install liner system is cost effective and essentially maintenance free compared to steel liners. The Valley Rubber technology is used in a variety of trucks on an international basis from 50 ton up to 420 ton trucks.

Benefits include:

* Abrasion resistance;

* Greater equipment availability; 

* Eliminate box maintenance; 

* Lower cost-per-ton;

* Fast and easy installation; 

* Noise reduction;

* Increased driver comfort. 

Cronan Connell  is president Valley Rubber, LLC is based in Falkville, AL, USA.

Video: Valley Rubber can line heated and non-heated beds, offering extreme abrasion resistance and reducing metal fatigue and stress fractures, while increasing driver comfort and reducing noise. The liner system is maintenance free compared with steel liners, increasing equipment availability

Janne Alatalo looks at the benefits of compact low-harmonic drives for use in the harshest environments

Energy production in mining operations requires precise, reliable motor control on a continuous 24/7 basis, often under very difficult conditions. Drives are vital for pumps, conveyors and crushers in mining. Any breakdown causing lost production can be very costly, thus making reliability and uptime a top priority.

To meet these demanding requirements, ABB has developed the new ACS800-38 low-harmonic drive.

By completely rethinking traditional designs, the standard container with the drive and added air-conditioning unit can be replaced with a high-reliability, all-in-one turnkey ACS800-38 solution built on a much smaller footprint. 

Key benefits and advantages of the new low-harmonic drive include: 

* Specific focus on high uptime and reliability, even in the weak power networks that are common in remote locations.

* Completely new cooling technology with no external air reaching the drives, so drive maintenance and changing of air filters is reduced.

* Robust components for reliable operation and long life in climates like hot sandy deserts and harsh mines.

* A compact, easy-to-move thermally-isolated enclosure that can be transported and installed without difficulties by forklift or crane.

The ACS800-38 integrates an active supply unit and low-harmonic filter that effectively eliminates harmonic issues, without need for additional filtering equipment or multi-pulse transformers. This low-harmonic drive also maintains unity power factor for maximum efficiency.

The closed-loop air cooling method prevents any sand or dirt from reaching the drive, thus reducing maintenance and unplanned downtime. 

The drive has application motor control with DTC (direct torque control), as well as built-in pump control software. Remote monitoring is available, and several drives can be controlled simultaneously.

Transportation is easy, and the plug and play design means quick and durable electrical connections to both the power supply and the motor. This turnkey drive solution comes with IP55 enclosure class as standard and IP56/NEMA 4 as an option. The power range is from 110 to 355kW (125 to 450hp), which will be extended up to 630kW. The robust double layer thermal cabinet is designed to work in temperatures up to +55°C (+131°F).

The new ACS800-38 has received considerable interest from mining customers attracted by the unique combination of proven low-harmonic drive technology with a cleaner cooling-loop system in a compact but tough enclosure.

Video: The ACS800-38 low harmonic drive for outdoor use boosts productivity without compromise in the harshest of environments. This drive is suitable for dusty, windy and humid environments in the oil and mining sector. The drive can be used to control industry application such as ESP, PCP and booster pumps, conveyors, feeders, compressors and crushers

Peter Cravan looks at how equipment manufacturers can deliver processing systems that are fit for purpose

A major challenge for equipment manufacturers in the years ahead will be to provide materials processing systems that are able to be efficiently deployed in increasingly remote locations. 

There will also be a requirement to process increasingly difficult materials that have been overlooked until now. As our demand for steel, aluminium, copper and silica sands and other industrial minerals continues to increase mining companies are constantly looking for new and improved processing technologies that will allow them to process lower grade ores and industrial sands and produce final products suitable for use in downstream processes.

Another development we have witnessed is an increased focus on staged investment as a means of delivery for new mining projects – designing your plant in such a way as to allow for production to begin in the shortest possible timeframe while planning for further plant and process development. 

To use the age old adage ‘the customer is always right’, if mining companies are looking for equipment that can be more efficiently deployed, that can process increasingly difficult materials and that are is suitable for staged investment then it is the responsibility of equipment manufacturers to meet these requirements.

In looking at how we can do this I will look at a number of issues which can be categorised under these headings:

* Built with the application in mind;

* Modularity;

* Intelligent Process Integration;

* A phased approach to design and delivery;

* System adaptability;

* Mobility – without compromise;

* A turnkey approach.

It is clear to all involved in the delivery of mining projects in the 21st century that there are many complex issues to overcome. The demands of the industry are constantly evolving and it is essential that the products offered by equipment manufacturers continue to evolve. It is equally important that equipment manufacturers develop their processes and approach to project delivery in order to continue to meet the demands of the industry.

There are three main considerations in this analysis of how equipment manufacturers can continue to supply mineral processing systems that are fit for purpose.

1. The individual components that make up a complete processing plant cannot be looked at in isolation and should instead be made up of modular systems with the in-built flexibility to cope with shifts and changes in individual project circumstances.

2. Off the shelf processing systems from a collection of different manufacturers will not deliver the efficiency required of 21st Century mining projects. A tailored approach is required with each individual project being built according to the specific requirements of the project – capacity, feed material and potential for future development.

3. Equipment manufacturers must get closer to the project and the end-user and understand the background, the specific objectives and the plans for future development. For most equipment manufacturers this requires a huge shift in the way their business models are constructed. Our business has always been constructed on the principle that direct contact with the end-user is critical to success.

Peter Cravan is with CDE Global, Cookstown, County Tyrone, Northern Ireland, UK.

Randgold Resources’ chief executive Mark Bristow discusses the issues of sustainable mining and the impact for local communities

The Loulo-Gounkoto gold mining complex is the largest of its kind in Mali and one of the largest in Africa. Randgold Resources owns 80% of the complex with the state of Mali holding the rest.

Loulo-Gounkoto currently accounts for some 8% of the country’s GDP. In addition to the substantial contribution it makes to the Malian treasury in the form of dividends, taxes and royalties, Loulo-Gounkoto’s  success has also enabled it to provide a wide range of life-changing benefits to local communities.

“Our principle commitment is on the three primary foundations of society … and that’s clean water, primary education and primary health. And when it comes to clean water it’s not negotiable. If we see an opportunity to supply clean water we do. We’ve measured the impact of that on mortality rates, on every aspect of personal hygiene. Clean water has a massive impact. Likewise with primary health, whether its maternity, pre-natal, education, and post-birth child care. That reinvests back into the family units, making sure people are responsible for their children and about having children, ” says Mark Bristow, Randgold Resources’ chief executive.

Mr Bristow, a geologist with a PhD from Natal University, South Africa, has held board positions at a number of global mining companies and is non-executive chairman of Rockwell Resources International. Has also played a significant part in promoting the emergence of a sustainable mining industry in Africa.

He outlines three key steps in achieving sustainable mining: profitable mines, investment in skills and education.

“The first thing is that to have profitable mines. That’s the biggest project one can deliver on. We’re one of the largest employers in the country outside government and we’re one of the largest taxpayers. So the taxes we pay get very close, if not cover, the national civil service tax bill. That the first and most important thing a mining company should do.”

Randgold contributes to national skills growth in Mali through scholarship programmes, hands-on training and career development. As a direct result of this effort, Loulo-Gounkoto is managed and operated by an almost entirely Malian team, with the country’s nationals accounting for 94% of the total workforce.

“When it comes to Rangold’s mines, it is a worldclass operation with world class skills and we’ve created some seven-and-half-thousand new jobs in Mali. Those are direct jobs,” says Mr Bristow.

The third step is primary education. “If you don’t get young people into the classrooms then you just can’t make a difference in society.”

But building schools is not enough. “What we really need to measure is how many children we educate properly and the quality of that education … you can build all the schools in the world but, if you don’t have teachers, you can’t deliver the best. So what we do now is measure pass rates rather than brag about how many schools.”

In addition, the Rangold has set up community-led commissions to direct each of its strategic community investment sectors, including potable water provision, education, healthcare and food security. Investment projects are run by the community, with guidance from Loulo-Gounkoto’s management.

Another initiative is the development of local agribusinesses. The relevant community development committees are being converted into co-operatives, which will secure agricultural land selected by the communities and tested by Mali’s National Agricultural Institute. Construction of an agricultural training centre will also start this month and a number of pilot projects, which will serve as training units, have been identified.

“We invest not in trying to perpetuate subsistence farming but it’s about how do we take subsistence activities and convert them into real economic businesses that have a margin.”

To boost the local economy generally, the complex will fund a microfinance provider to help finance small business initiatives, particularly those started by the women in the community.

One of the issues Rangold still has to address together is the challenge of illegal mining, which impacts on Loulo-Gounkoto’s capacity to deliver these benefits and threatens the integrity of Mali’s vitally important national assets, damaging the environment and exploiting sectors of the community.

Illegal mining is “the scourge of Africa,” says Mark Bristow, leading to, child labour, enslavement of women and massive environmental degradation.

Randgold Facts Box

Major Randgold discoveries to date include the 7.5Moz Morila deposit in southern Mali, the 7Moz Yalea deposit and the 5.5Moz Gounkoto deposit, both in western Mali, the 4Moz Tongon deposit in the Côte d’Ivoire and the 3Moz Massawa deposit in eastern Senegal.

Randgold financed and built the Morila mine which, since October 2000, has produced more than 6Moz of gold and distributed more than US$2 billion to stakeholders. It also financed and built the Loulo operation which started as two open pit mines in November 2005. Since then, two underground mines have been developed at the Yalea and Gara deposits.

The company’s Tongon mine in Côte d’Ivoire poured its first gold in November 2010. Gounkoto, south of Loulo, delivered first ore to the Loulo plant in June 2011 and paid its first dividends to shareholders in mid-2012.

In 2009, the company acquired a 45% interest in the Kibali project in the Democratic Republic of Congo (DRC), which at 12Moz of mineral reserves is one of the largest gold deposits in Africa. Gold production started in the third quarter of 2013, ahead of schedule.