Time is money has never been so important a concept in the mining industry; from the drastic downturn of 2015 and 2016, where new investment virtually dried up, though to 2017 with an upturn, it is abundantly clear that money is still very tight. Money in the bank earns interest, but money in a mining venture is dead until the first minerals flow or gold is poured. Here’s our take.
Classically comminution is associated with crushing and grinding to a fine size, something like the well established norm of 75 microns. But especially where the purpose is either flotation or even more so gravity concentration then the coarser the mineral can be liberated the better, within the upper limits of the process of course. Even where the purpose is cyanidation, finer grinding is dictated by the dissolution curve, and going beyond the optimum just entails extra grind energy. In a nutshell, it is definitely a case of horses for courses and one size definitely does not fit all. Then there is the effect of mineral hardness and brittleness. Some minerals, for example scheelite or cerussite grind far faster than the host rock and if the only consideration in the P80 of the total then certainly the target would have been preferentially ground well beyond that, rendering recovery difficult to impossible. So the methodology is to first remove any naturally occurring fine target before gently crushing the remainder in closed circuit with a screen to take off successive amounts as they are generated. Rolls crushers are particularly useful for this gentle crushing role.
Impact crushing has proven to me metallurgically advantageous because the energy goes into splitting the rock upon fracture planes or zones of weakness, like grain boundaries. The result is mineral liberation at a disproportionately large particle size and APT has termed the phrase ‘early liberation to describe this. APT uses its own design RD impactors for this duty, which utilize very high impact energy for breakage.
In cases where minerals are hosted in an oxidized matrix it is useful to use an efficient scrubbing device like the APT RG scrubber, where the retained rock load in the scrubber acts like an autogenous mill to break up the friable lumps without pulverizing the mineral itself.
FLOWSHEET IMPLICATIONS
A typical APT approach is to first target the scrubber amenable fines and then impact the oversize after a jaw crush to reduce oversize lumps. The resulting product is recycled to the scrubber to remove the generated fines and the surviving oversize either goes around again, or progresses to a rod mill for a further nip. The RD impactor may be replaced by a rolls crusher in certain cases.
A typical flowsheet is depicted below, in this case for ultra soft target mineral.
TESTING
APT’s associate laboratory Peacocke & Simpson is equipped with all of the comminution devices to test which is best suited to your ore’s mineralogy. The lab then applies gravity or flotation and/or cyanidation to verify the choices and estimate the potential recovery. Usually a 100kg sample is required.
DESIGN
Once the groundwork has been established, APT’s engineers can progress to a process design and plant costing with confidence, and then install the correct plant for the job.
For further information, please contact us here, we are always happy to help.
Mining in Zimbabwe has been an adventure for us here at APT over the years, and with the recent attention in the country, we think it fitting to place some focus on the huge potential it has. APT has installed and commissioned several processing plants in the country, from gold recovery through to chrome recovery, tantalite recovery, tailings re-treatment and more. We have assisted a variety of miners, from those just starting out through to those well advanced in their mining journey, in both knowledge and experience. We don’t anticipate the Zimbabwean mining sector slowing down anytime soon, so if you’re looking into getting started there, you’ve come to the right place!
Here are a few testimonials from our past and present Zimbabwe based clients. The videos linked to each product are for the same product, though on differing mine sites:
We invite you to browse the APT website, see our videos and scroll through the various plant options available. For detailed information on mining in Zimbabwe and APT's experience, please contact us.
We look forward to assisting you in starting your Zimbabwean mining venture!
Having recently celebrated Women's Day here in South Africa, it comes at a fitting time that we congratulate the Environmental Women in Action on the acquisition of an APT GoldKacha concentrator. We are proud to work alongside such people and look forward to seeing their journey unfold. This also inspired us to look back on our own mining journey, one which continues to bring us much pride and joy. We have worked with men and women across the globe; some looking for large projects, some smaller projects, some just starting out and others far advanced. All with the common goal to mine. Doing so in an environmentally conscious way is something we strive for, without compromising on recoveries. We also have the men and women who make APT what it is today and if you have stepped into our offices, you would see the work and time each person contributes.
Here are some videos which show a small part of the APT journey:
[embed]https://www.youtube.com/watch?v=zrI0wII3-mQ[/embed]
[embed]https://www.youtube.com/watch?v=Chw_Dri8NiA[/embed]
[embed]https://www.youtube.com/watch?v=tdMChNw_E8s[/embed]
APT are proud to have received great feedback from our clients mining in Burkina Faso. The miners are happy with their gold mining equipment consisting of the GoldKacha concentrator and GoldMasta sluice, for optimal recovery. Thank you to our clients for sending the below video to give us, and you, a look at their Burkina Faso mine site! [embed]https://youtu.be/s7SPIVfpouw[/embed]
For further videos of the GoldKacha and GoldMasta, as well as various other mineral processing plants, please visit our website here. For further information on our mining equipment, please contact us and we will be happy to help!
The APT installation and commissioning team just returned from a successful mine site trip in Southern Africa to install and commission yet another one of our modular TriTank cyanidation plants, the TT20. We have a whole article dedicated to the TriTank where we explain it all more in depth, so if you have not yet heard about the TriTank we recommend giving it a read. This plant is a step away from conventional CIP/CIL cyanidation plants and is not only more efficient, but is also more environmentally conscious. Being triangular in shape, our six sectors fit into one circular tank, creating a range of benefits from on site cleanliness, efficiency, smaller land footprint, less material usage and more. Recoveries are high and we are so proud to have designed this plant and made it a part of our mining equipment range. The TriTank is not limited to this size, we also offer a much larger modular version which you can see operating on site here. Congratulations to the team and thank you to our valued clients. We hope you enjoy these clips from site!
https://youtu.be/fztYO04JJAE
APT has received the order for a 20tph lead concentrating plant destined for Eastern Europe. This major milestone demonstrates the client's faith in APT's ability to deliver this important facility on time and within budget. It also underlines APT's growing diversity into the wider spectrum of mineral recovery, which to date includes gold, platinum, copper, tantalite, tin bauxite, wolframite, chromite and gemstones. Congratulations to our APT team and we look forward to making this project a success.
APT has just completed installing a 3tph tailings retreatment plant in northern Zimbabwe for a regionally based client. The plant comprises of a ball mill, feeder, classifier and two APT TriTank® CIL tanks. Designed to treat high grade artisanal tailings the set up incorporates several features to allow for a trouble free, robust solution. The plant was completed on time and installed in a short four days. “I am very pleased with the plant installation” said project consultant Garth Barton, “It went together virtually faultlessly.”
APT wishes their client Comprecraft a successful future for their many local and regional projects.
Kevin Peacocke
CEO
Comprecraft plant: Feeder, classifier, two APT TT20 CIL units.
The past few weeks have been nothing short of a whirlwind at our offices and we have loved every minute! The buzz of the welding coupled with the hum of the forklift and chatter of the workers just added to the excitement in the air, it is the middle of the year and 2018 is in full swing.
Shown above is a picture from our Instagram live platform (be sure to give us a follow on @aptprocessing for up-to-the-minute updates), of one of our most recent plants, and favourites to build, the APT TriTank TT20 CIL circuit. We manufactured two TT20's for this particular project, along with a feeder, conveyor and milling module. The plant was built and pre-assembled in our offices in Johannesburg, then freighted to its final destination in Southern Africa. From this point on, most of us do not see the plants until they are fully installed on site, so we look forward to the installation and commissioning updates as much as you.
As soon as the plants arrive on site, our on-site team gets to work efficiently. This is what they did after a day or two, and we look forward to seeing the end result!
Here is the RG30 scrubber and GoldKacha on a mine site in South America. Thank you to our clients for sharing this one with us! [embed]https://www.youtube.com/watch?v=HVqT2riT4Cw[/embed]
