Delivering Processing Systems That Are Fit for Purpose
Peter Craven, head of marketing at processing equipment supplier CDE Global,
outlines how manufacturers can meet mining industry demands in the years ahead
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.
Another development is an increased focus on staged investment as a means of delivery for new mining projects—designing a 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.
In looking at how to do this, Peter Craven, head of marketing at CDE Global, discussed a number of issues that fall under seven fundamental objectives: Build with the application in mind— Every project presents its own unique challenges. When looking at the raw material, there are several factors that will influence the selection of the appropriate processing system. The quality of the ore is the first issue to consider. In addition to this, level of contamination needs to be analyzed 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, the levels of silica and alumina contamination will need to be consided, 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.
Taken 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 maximize 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 customers that tailoring each individual project is not possible, the reality is that it is entirely possible. CDE’s experience in the mining sector has shown that there are a number of individual considerations that need to be made in order to maximize 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 minimizing 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 improve wear resistance, maximize plant productivity and reduce costs of operation through a reduction in spare parts requirements. 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 rigors 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 CDE’s 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 maximize material retention within the circuit and avoid bottlenecks within the system where the discharge point from one processing phase is not optimized 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.
For 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 types of third-party equipment that CDE is most familiar 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 third-party equipment, CDE can ensure that the focus on transfer point technology does not stop at their own products but extends to outside equipment as well. As a result of this focus on tailoring each system, they are also able to manage the introduction of new equipment to their 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 maximized. Additional advantages are a reduced plant footprint, which results in reduced civil-engineering requirements. 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 time spent on designing infrastructure to accommodate all of this equipment. Once the equipment reaches the 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.
Shorter mechanical installation times can be achieved when 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.
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 needed for mechanical install, 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 investment much more quickly. The start of this process will be detailed discussions with a client’s mining engineers to understand the specifics of the reserve—capacity requirements, likely requirements for future upgrades. This will also involve a detailed analysis of mined 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 an area containing 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 clay-bound 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-utilized for a period of time operators can take delivery of first-phase equipment in as little as 12 weeks. This allows clients 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—The variability that is inevitable within mining projects and what is required at the outset may change over time has been touched upon. Future developments with a business may require a capacity upgrade to meet a rise in demand for the product. CDE may come across an area of their 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 the processing system has built-in flexibility to respond to these changes. CDE can’t predict the future but through a comprehensive analysis of the material, they can identify, for example, whether there is likely to be a requirement for an additional process to be introduced and when this is likely to happen given the extraction plan for the reserve.
If CDE has established that the business plan indicates a likely requirement for additional capacity as extraction progresses, they will design the infrastructure onsite to take this into account—minimizing disruption to the operation. CDE 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 CDE 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 layout. CDE 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—As mineral extraction progresses it makes sense that the 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 extraction progresses, operational efficiency is reduced by increased transport movements on-site as vehicles have to haul material greater distances to the processing plant, or unnecessary double handling of 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, clients ensure that their processing plant can be moved quickly and easily within the deposit—or to another processing location—in order to maximize 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 that 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 CDE believes that even on mobile or portable plants, the walkways for access and maintenance should be of the same specification as that found on a static plant. This ensures that users continue to enjoy all the benefits of a static plant in relation to maintenance access—ease of visual inspection, access to change screen media, replace spray bars, and 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 that 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 21 st 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.
CDE’s own process is split into three distinct phases: Technical Pre-Sales, ProMan and CustomCare. In Technical Pre-Sales, the elements include process design, equipment selection, mechanical design, civil design and third-party equipment integration. As they 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 the plant has been successfully installed and commissioned, their range of after-sales services are activated including their MasterClass training programs, service visits, recommended spare parts lists and ongoing maintenance contracts.
The effect of being able to offer this complete range of services in addition to the equipment that CDE provides, 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 their process provides customers with a dedicated single point of contact throughout the project lifecycle to ensure they remain fully informed at every stage of the project. Another advantage of this approach is that it helps to develop both their knowledge of a business and knowledge of their capability, which will allow both parties to explore the potential for further co-operation in the future.
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, there are three main considerations in this analysis of how equipment manufacturers can continue to supply mineral processing systems that are fit for purpose.
• 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 built-in flexibility to cope with shifts and changes in individual project circumstances.
• 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.
• 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. CDE’s business has always been constructed on the principle that direct contact with the enduser is critical to success. They have been delivering projects in this manner for more than 20 years and their project portfolio across all the sectors in which they operate is evidence of their success.
This article was developed to accompany a presentation by CDE Mining at the Bulk 2014 conference in England, sponsored by the Materials Handling Engineers Association (MHEA), held May 21. Further information on the conference and the MHEA can be found at www.mhea.co.uk.