Pilot operations

Proving viability of continuous processing

Bench scale testwork provides a raft of project design and operational criteria. However, the majority of green-fields projects will eventually need to undergo continuous piloting to ascertain the effect of recirculating streams and prove the process can reach, and sustain continuous equilibrium. Another important objective of a pilot plant is to produce product mass for further testwork and marketing purposes. These are critical project milestones and clients need a reliable provider with the necessary capability and expertise to deliver their projects to completion. ALS is that provider.

HPGR5

Proven track record with huge equipment inventory

Industrial processing plants are engineered for purpose. Pilot plants are not, and thus the plant set up is intricate and requires great innovation to cater for sampling, low flowrates versus particle size distribution, and mismatching unit processes. ALS has a dedicated team of metallurgists and technicians who are expert in pilot operations. With one of the largest equipment inventories in the world, this capability has been proven over decades and hundreds of pilot campaigns, many of which have successfully gone on to construction and operation.

Fábrica de flutuação

Piloting Testwork Services

Every pilot plant is different. For this reason, ALS chooses a modular (skid-mounted) approach to pilot plant set-up to effectively allow unlimited options. Each of the skids, plant modules, or proprietary equipment items must be connected via pipes and pumps, and at times decoupled by surge tanks and/or stop points requiring full dewatering and drying. Set-up needs to be as ergonomic as possible to allow for safety, sampling, and resources. If we don’t have the exact equipment in our inventory, then usually there is an engineering/fabrication solution, purchase/hiring of new equipment, or leveraging of alliances with vendors (e.g. Eriez, Outotec-Metso, Tomra, Köeppern). We always work something out.

Broad pilot plant set-ups fall into the following categories (click on the links for more detail):

One critical element of testing common to all pilot plant is sampling and monitoring, together with all of the infrastructure to process the samples and data collection. ALS has the complete capability to facilitate all requirement of sampling, from drying, preparation, sizing, analysis, and dispatch to third parties.

ALS always keeps sample representivity in mind when designing the sample process and taking the samples from the plant/process. Representative samples lead to statistical veracity and ultimately to a meaningful mass balance properly capturing plant performance at the target product specification. Wherever possible, ALS uses the principal of cutting full stream for a significant time (for flowrate streams) or using proven sampling techniques (i.e. Cone and Quartering, Riffle Splitting, and/or rotary sample dividers) for bulk solids parcels).

Typical pilot sampling requirements are as follows:

  • Head samples
  • Sizing samples
  • Control grab samples
  • Shift Composite
  • Survey samples
  • Reagent additions
  • Probe monitoring
  • Engineering/vendor samples

Finally, it comes down to mass reconciliation. We understand the importance of your samples, and from hard lessons that were learned in the early days. ALS takes extraordinary care in capturing and measuring every stream. Spillages and losses (e.g. to dust and moisture) are unavoidable, but strict sample collection and measuring control, ALS routinely has mass reconciliation at 99.5% (i.e. 0.5% unaccounted loss).

Here are some frequently asked questions

  • Will ALS provide a fixed price quote and schedule?

    No. Our quotes are budget estimates, as are our schedules. Metallurgical testwork is not prescribed engineering. There are too many unknowns and variables to commit to lump sums. Our business approach, however, is to provide realistic, honest and transparent budgeting and any variations are always done in conjunction with the client prior to completion.

  • Can I reserve a time slot for my pilot run?

    Yes. Provide with a finance commitment (i.e. PO) and we will reserve a spot in the queue, if there is one, otherwise we'll get right on it. Keep in mind that slot timings may vary due to unforeseen delays.  ALS will always honor its commitments to existing programs.

  • How much does a pilot plant cost?

    Well...how long is a piece of string? Every pilot plant is different so we will need a scope of work to compile a quotation. Don't have a scope of work, no problem, we can help you define what we can do for you versus your needs. See next question.

  • Roughly, what do you need to know to quote a pilot plant?

    Below is a list of questions we would likely ask in the case of limited information:

    • Is the sample hazardous? (i.e. radioactive or fibrous?)
    • When do you need it done? (i.e. schedule and milestones)
    • How much mass to treat (tonnes, kg)
    • Material size distribution (i.e. coarse or fine)
    • Crushing and grinding requirements (i.e. Natural and Target P80’s)
    • Material characteristics (free flowing hard rock or soft sticky clay, ROM, or drill core)
    • How will the samples be packaged on delivery?
    • How many sub-samples are there?
    • Are there intermediate composites to be made first? If so how many?
    • What testwork has been done to date?
    • What type of testwork required? (i.e. a process circuit describing the unit process type)
    • Throughput and run time required (if any)
    • Mass and specification of final product(s)
    • What reagents are required?
    • Day shift operation or 24 hours
    • Sampling requirements.
    • Vendor samples and vendor testwork requirements (i.e. third parties)
    • Sample dispatch requirement?
    • Sample disposal or return to client requirements?
  • What is the maximum top size and mass you can handle?

    Generally, 200 mm top particle size. Any bigger than that and they won’t fit into our largest jaw crusher. In terms of mass, our blending room can handle 100 t lots at one time. Larger masses would need to be batch processed.

  • Will ALS treat hazardous samples?

    Generally, yes. ALS has facilities and procedures to treat fibrous and radioactive samples. Surcharges do apply, however, to cover safety equipment, monitoring and decontamination. /p>

  • Our samples are from overseas, what do I do?

    ALS is a quarantine approved premises and treats many samples of oversea origin. Strict regulatory requirements are in needed around packaging and paperwork, however, ALS can advise you on these requirements.

  • Can my associates and I view the testwork at ALS?

    Yes, clients are always welcome to visit our facilities and observe samples or tests in progress. Inductions are required and other rules may apply to visitors.

  • Will ALS dispatch my samples to third parties?

    Yes, if a testwork program is in progress, ALS will happily dispatch testwork products and feed samples to vendors, third party laboratories, and customers as required. Fees apply.

  • Does ALS do bulk gold pilot testwork?

    Generally it is not required as the engineering around gold processing is so highly developed after many decades and the construction of hundreds of gold processing plants. Exceptions do arise, however, so contact us if you have an unusual requirement and will see what we can do to assist.

  • Does ALS do design engineering and consulting on pilot results?

    No, as it is not our core business and would put us in direct competition with many of our clients.  We can, however, put you in contact with a range of reputable engineering providers and consultants.