What a CIP gold plant is
A gold plant design for a carbon-in-pulp (CIP) flowsheet is built around one task: moving dissolved gold from a cyanide leach slurry onto activated carbon, then off the carbon again as a concentrated solution. The circuit itself is a sequence of tanks, screens, columns and cells, and the gold plant layout has to let slurry and carbon move in opposite directions without fighting gravity. Xinhai reports it has served more than 2,500 mines and reports more than 600 Mine EPC+M+O projects, but no two CIP plants are identical. Process selection, tank sizing and carbon inventory all follow from testwork on your ore.
A CIP plant is not the same as a CIL plant. In CIL, leaching and adsorption happen in the same vessel; CIP keeps them separate. That difference changes carbon residence time, carbon breakage and the number of tanks you need. If you're comparing the two, the CIL vs CIP comparison walks through the trade-offs.
The CIP circuit stage by stage
A carbon-in-pulp plant is a hydrometallurgical recovery circuit that uses activated carbon to extract dissolved gold from a cyanide leach slurry. The design has five main stages: (1) leaching, where dual-impeller agitation tanks dissolve gold into solution; (2) carbon adsorption, where the slurry passes through a counter-current train of carbon tanks; (3) elution, where loaded carbon is stripped in an elution column; (4) electrowinning, where the gold-rich eluate is plated onto cathodes; and (5) smelting, where the plated gold is melted into doré bars.
Elution is a batch process, not a continuous one. Column size is set by the mass of loaded carbon the circuit moves each day. That batch size fixes the stripping circuit's heat load, solution volume and the electrowinning cell duty downstream.
Key equipment and selection variables
Each stage has a shortlist of equipment families. Leaching and agitation tanks up to 20 m × 20 m provide residence time for gold dissolution. Carbon handling, screening and regeneration circuits move carbon counter-current to the slurry and recover fine carbon. Elution columns strip gold from loaded carbon, while electrowinning cells and a gold room recover the metal from solution.
| Circuit stage | Primary equipment | What the designer fixes |
|---|---|---|
| Leaching | Dual-impeller agitation tanks, high-efficiency or lifting tanks | Tank volume, residence time, impeller type, power density |
| Carbon adsorption | Carbon tanks, carbon screens, air lifters | Number of stages, carbon concentration, slurry flow direction |
| Elution | Elution column, high-efficiency desorption electrolysis system | Batch size, temperature, pressure, stripping time |
| Electrowinning | Electrowinning cells, gold room | Cell current, cathode area, solution flow |
| Smelting | Smelting furnace, doré bar moulds | Flux addition, melt temperature, pour schedule |
Equipment selection for these families is not a catalogue exercise. The knowledge base for gold extraction equipment links process type—CIP, CIL or zinc displacement—to slurry throughput, gold grade, leaching time, carbon concentration and the required desorption batch. Agitation equipment selection depends on tank volume, residence time, slurry density and particle size, viscosity, impeller form, power density and corrosion-resistant materials. Thickeners and filters, when used for tailings or concentrate dewatering, are selected by solids flux, settling or filterability tests, feed concentration, target underflow density or cake moisture, and the flocculant regime.
- Leaching and agitation: dual-impeller leaching tanks, high-efficiency tanks, lifting tanks, high-concentration tanks, reagent and acid-washing tanks.
- Carbon handling: carbon screens, air lifters, carbon regeneration kilns, deoxygenation towers and carbon adsorption columns.
- Dewatering: high-efficiency improved thickeners, hydraulic centre-drive and peripheral-drive thickeners, deep cone thickeners, disc, ceramic and belt vacuum filters, filter presses and vertical filter presses.
Ore testwork: the starting point for gold plant design
Design starts with ore testwork, not with equipment drawings. Element analysis, leaching kinetics and carbon adsorption tests fix the tank sizes, carbon loading and residence times. Xinhai operates a CNAS-accredited laboratory and industrial pilot base; the company reports it completes around 5,000 element analyses per month and about 200 beneficiation tests per year. Bond work index testing is used when comminution design matters, because a P80 of 75 µm simply means 80% of the ore mass passes a 75 µm screen. That number drives grinding circuit design and, in turn, the size of the leach tanks downstream. The laboratory's CNAS accreditation follows ISO/IEC 17025, as described on the CNAS website.
Leaching residence time is determined by how fast your gold dissolves, not by a fixed number. Carbon loading is set by the adsorption isotherm and the number of carbon stages. Batch elution size is matched to the daily carbon movement. On suitable ores, CIP recovery can reach 99%, but that is a testwork-driven ceiling, never a blanket guarantee.
Gold plant layout: moving slurry and carbon safely
Gold plant layout is a real engineering constraint, not an afterthought. A CIP plant should use gravity where it can: leach tanks feed adsorption tanks by overflow, and loaded carbon is pumped or air-lifted upstream against the slurry flow. The layout must separate the cyanide area from non-process areas, keep the gold room secure, and provide bunding around every cyanide-bearing tank. Cyanide is toxic, and its handling is governed by compliance and safety procedure, not by catalogue selection. The International Cyanide Management Code is a voluntary industry programme covering the production, transport, storage and use of cyanide; signatory operations are certified through third-party audits.
From the knowledge base, thickener and filter selection variables include solids flux, settling tests, feed concentration, target underflow concentration, overflow water quality and flocculant regime. Those matter for tailings and water recovery, which sit at the edge of the CIP layout. A poorly laid-out thickener or filter building can block carbon movement or force extra pumping. In practice, the design institute behind Xinhai's plants works to JORC, NI 43-101 and VALMIN standards for reporting and design discipline. NI 43-101 is the Canadian national instrument governing disclosure of scientific and technical information about mineral projects, and the JORC Code sets minimum standards for public reporting in Australasia.
Sizing and engineering constraints
Leaching and agitation tanks up to 20 m × 20 m are not arbitrary upper limits; they reflect the practical size of a single mixer that can keep coarse solids suspended. Xinhai's manufacturing capability includes ball mills up to φ7 m, flotation cells of 320 m³ single-tank volume and thickeners up to φ100 m. The company operates three smart manufacturing bases covering about 110,000 m² and reports more than 1,000 equipment types, supporting plant designs up to 50,000 t/d. That breadth matters when a CIP plant grows from a 4,000 t/d carbon-in-pulp circuit to a 15,000 t/d EPC project. Xinhai reports a 4,000 t/d gold carbon-in-pulp plant in Kyrgyzstan, as shown on the Kyrgyzstan gold plant page.
Those figures come from Xinhai's published project list and manufacturing data. They are useful for context, but they do not replace mass balance calculations for a specific ore. A 20 m × 20 m leaching tank is not a universal answer; it is an upper envelope of what the company fabricates and ships.
Planning a gold CIP plant: from testwork to proposal
If you're planning a gold CIP plant, the sequence is testwork, flowsheet selection, mass balance, equipment sizing, layout and capital estimate. Xinhai reports more than 600 Mine EPC+M+O projects across 100+ countries and 700+ technical experts covering 70+ ore types. The same design institute behind the company's plants holds a Class B metallurgical qualification in China and works to JORC, NI 43-101 and VALMIN design standards. That qualification is specific to China and does not function as a professional licence in other jurisdictions. Start with a testwork proposal or engage directly through the contact page; the CIL/CIP plant solution page shows the full cyanidation circuit, including leaching, adsorption and elution.