【Case】Sudan 300TPD Gold CIL Project

Far from Sudan in Northeast Africa, there is a vast territory with a sparse population and various resources. According to the statistics, Sudan has rich mine resources, especially gold and chrome. Other explored minerals includes silver, iron, copper, aluminum, mica, asbestine, talc, tungsten, zinc, diamonds, uranium and so on. It is actually a large mine country in Africa. However, the simple economy structure, behindhand industry basis and mineral processing technology limited the mine industry development in Sudan. Therefore, Sudan mine industry largely depends on foreign countries, which market has a large potential development.

Background

Commissioned to clients, Xinhai Mining provided this gold mine mineral processing EPC+M+O service, including design and research, complete equipment manufacturing and purchasing, commission and delivery, mine management and mine operation. During the construction, Xinhai Mining kept the idea, protecting investor profit, reducing investment and enlarging benefit, paid attention to the safety and health of workers at the same time. It strengthened the environment harmony, resource-saving and recycling in high efficiency, the high efficiency and energy-saving of single equipment and combined equipment. Each operation and the whole process is to achieve efficient recovery of gold ore. This success is the prove of Xinhai mineral processing EPC+M+O service in strength and technology.

Project Overview

Ore characteristic: the raw ore is gold tailings, with grade 4.70g/t and fine particle size. It needn’t be crushed while there are rag, wood, bottles and other impurities.

Xinhai scheme: pretreatment – one stage grinding and classification – concentration and cyanidation leaching – high-temperature high-pressure desorption electrolysis – gold smelting in high frequent furnace – tailing press filtering and dry stacking

Main equipment: double circular vibrating screen, overflow ball mill, hydrocyclone unit, thickener, double impeller high-efficiency leaching tank, desorption electrolysis system, high-frequency gold furnace, chamber filter press.

Xinhai solution

1. Raw ore feeding

The incoming materials are firstly stored in the raw ore yard and then transferred to the steel bin by forklift. The materials are transported to the double-layer circular vibrating screen by the belt conveyor below the bin for screening, and the debris and bulk ore materials are removed. The materials under the screen are transported to the ore yard for storage. The belt feeder is arranged below the ore yard, and the ore is fed to the belt conveyor and transported to the ball mill for grinding.

2. Grinding and classification

The ore transported by the belt conveyor is fed into the overflow type ball mill for a section of grinding, the ball mill is sent to the cyclone group for a section of grading by the slag slurry pump, the hydrocyclone is returned to the ball mill for further grinding, and the overflow gravity flow is used to remove debris, screen and remove impurities, and then the gravity flow is used to densification system.

3. Thickening, cyanidation and leaching

Hydrocyclone overflow pulp after trash screen in removing impurity, undersize pulp gravity to thickener for enrichment, thickener underflow concentration is enriched to 40%, with efficient slurry pump into the double impeller leaching tank for leaching and charcoal adsorption, and USES the roots blower to fill the air in the leaching tank, at the same time to join NaCN, pulp, reagents and air mix reaction.

The gold in the ore reacts with NaCN in an alkaline environment to form auricryl complex ions. The gold enters the solution and is adsorbed by activated carbon. During production, the carbon was extracted in reverse, and the saturated gold-bearing carbon was put into the No.2 leaching tank, and then put into the carbon extraction screen. The pulp under the screen was returned to the No. The clean saturated gold-bearing carbon is then fed into the desorption electrolysis system for gold extraction. The gold slime produced by electrolysis is melted in the high-frequency melting furnace to obtain the final alloy gold.

4. Tailings dry stacking

The cyanide tailings are driven into the chamber filter press by the two-stage pump for pressure filtration and dehydration. After pressure filtration, the dry tailings (with water content of 20-25%) are reversed to the outside of the factory by the belt conveyor, loaded into the car with forklift and transported to the tailings reservoir for storage. The filtrate of the filter press flows into the sewage treatment tank for clarification, and then the clarified water is transported to the return tank for recycling by slurry pump.

Advantages

1. Customized mineral processing EPC+M+O service

The construction is contracted by Xinhai Mining from mineral processing experiment, mine design, equipment manufacturing and purchasing, packaging and delivery, installation and commission, worker training, finishing to engineering management and mine operation. It is one-stop customized mineral processing plant solution. The project construction efficiency is high, time limit is short, put into production quickly. Secondly, the customer saves the worry and saves the effort, only needs to put forward the request and control the acceptance link, all the factory construction link all entrusts Xinhai Mining to install, achieves the customer with the unique innovation factory selection service mode, the specialized factory selection technical strength and the rich factory selection experience.

2. Adjusting measures to local conditions, production line design of steel structure concentrator

The whole plant is built according to the topography, and the equipment configuration in the rooms of the concentrator takes into account that the main pulp is self-flowing as far as possible. The operation of similar equipment is relatively centralized and easy to operate and manage. Xinhai Mining Mine Design Institute adopts steel structure members, which is convenient for flexible assembly, disassembly and movement in the mine site, which not only reduces the workload of civil engineering and construction time, but also saves the investment of infrastructure construction.

3. Environment friendly

Strict recovery and treatment of cyanide containing wastewater from the project to ensure that it does not cause harm to the surrounding environment;

Overflow water of the thickener flows into the return tank, filtrate of the tailing workshop filter press flows into the sewage treatment tank, and is returned to the return tank for recycling with a pump to realize zero discharge of production sewage;

The solid waste is cyanide tailings, and the tailings containing 20-25% water after being filtered by the press filter are transported by car to the dry heap of the tailings pond. The bottom and side walls of the tailings pond are paved with geomememes for anti-leakage treatment, so as to ensure no liquid leakage and effectively protect the environment.

Result

Pointed at the practical situation, Xinhai Mining choose reliable technology, practical, simple process, economic and reasonable process and simple operation, easy maintenance, high efficiency and energy saving mineral processing equipment. And under the condition guarantee the construction quality, the project is as investment-saving as possible. Finally, the leaching rate is 95.70%, the adsorption rate is 99.00%, the desorption rate is 99.00%, the total recovery rate is up to 91.93%, the customer is very satisfied with this!

At present, Xinhai Mining served over 2000 mines, over 500 mineral processing plant EPC+M+O projects in global over 90 countries and regions, involving over 70 kinds of ores with rich experiences. In Africa, Xinhai Mining has mineral processing EPC+M+O projects in Sudan, Tanzania, Zimbabwe, Nigeria, Morocco and other countries, and successively established multiple overseas offices, conducting business negotiation with many African mine corporation and reached cooperation intention. In the future, Xinhai Mining will continue response