Project Background

The whole tailings cemented filling system project of a lead-zinc mine in Guangdong Province was built by Huade Venture. The preliminary tests (dense test, cemented material ratio test and pipeline transportation test, etc.), equipment supply, civil construction, equipment installation and system joint adjustment of the project were all implemented by Huade Venture. The project was put into operation at the end of August 2019 and has been in stable operation for 5 years. The whole filling system represents the highest level of the whole tailings cemented filling industry today, the filling process is as follows:

The filling system is mainly composed of raw material tailings transportation subsystem, tailings concentration subsystem, tailings mixing and mixing subsystem, concentrated water subsystem, filling control subsystem, cement supply subsystem, pipeline transportation subsystem, water supply and power supply subsystem, etc.

The full-tail mortar with a mass concentration of 10% ~ 12% produced by the concentrator is pumped into the newly-built deep cone paste thickener to concentrate the low-concentration tailings to about 66% ~ 68% high-concentration tailings. The bottom of the deep cone paste thickener adopts gravity flow to transport the concentrated high-concentration tailings to the mixing system. The deep cone thickener is equipped with an underflow circulating shear pump for activation to prevent pressure rake failure of the thickener. During non-filling time, the bottom flow of the thickener is diluted and sent to the existing filter press workshop.

To achieve the effect

1) Process optimization

Compared with the traditional sand bin filling process, the maximum optimization content of this process is: cancel the sand bin and supporting high-power air compressor and nozzle, etc., simplify the process, reduce the overall investment, greatly reduce operating costs. Since the operation system of the selection plant is 24h continuous production, and the filling operation is designed for 12~14h/d in the first three years (5~7h/d in the later period), the common vertical sand silo or horizontal sand silo is used for caching in the preliminary design to meet the flow required for the filling operation. The vertical sand silo has large height and high construction difficulty; the horizontal sand silo covers a large area, which requires great requirements for the project site. At the same time, the large amount of compressed air power consumption required for slurry making in the sand silo is extremely large, and the operating cost is greatly increased. Therefore, this process adopts a new type of deep cone thickener technology, can store a certain period of time of tailings feed, increase the stable sand release range, to ensure that long-term large-flow filling sand, no need to set up sand warehouse, not only reduce the infrastructure investment and equipment investment, but also greatly reduce the operating power consumption. At the same time, it reduces the pressure on the originally limited industrial site.

2) Reliable equipment

As the core equipment of this filling system, HDCY thickener was born to solve the pain points and technical difficulties of the industry. In addition to the characteristics of the first echelon thickener on the market, HDCY thickener also has the following unique technological innovations:

① Anti-pressure rake multiple protection system design, so that the thickener "never pressure rake" as possible

HDCY thickener whole system comes standard with imported Dinamic drive reducer, Brivine and Bonfiglioli optional, through the hydraulic oil pressure, to achieve the most accurate monitoring of torque, supplemented by intelligent diagnostic expert system, to ensure that the equipment operation rate to reach the extreme;

The HDCY thickener is equipped with a rake lifting/lowering device, which is used to quickly release the resistance when the torque increases to the set alarm torque when the equipment is running, which plays a vital role in preventing the thickener from pressing the rake and reducing equipment failure.

Four-stage protection of driving device (adjustable ratio)

• Automatic alarm and rake lifting at 50% of MAX torque (electrical protection)

When 75% of MAX torque is reached, the "air-water linkage slurry making" system starts to disturb and activate the bottom mud to prevent the occurrence of pressing rake and harding (physical protection)

• Automatic tripping and motor stopping at 95% of MAX torque (electrical protection)

• At 100% of the MAX torque, the hydraulic relief valve is opened to prevent the reducer from being damaged (physical protection)

The above-mentioned multi-protection system design of the anti-pressure rake makes it possible for the thickener to "never press the rake" and has a service life of more than 20 years.

② Three-stage defoaming system setting, the tailings foam management to achieve the ultimate

The complete defoaming system of HDCY thickener is composed of the overflow weir bubble blocking plate of the special spherical spray device of the atomizing fan nozzle group.

First-stage defoaming device --- several atomizing fan-shaped nozzles are evenly distributed around the overflow weir, and after starting, the foam is driven to the direction of the feed well and initially defoamed.

Secondary defoaming device-a special spherical spray device is arranged under the bridge to spray the accumulated foam with high coverage

Three-stage defoaming device --- The bubble barrier of the overflow weir is set on the inner side of the U-shaped overflow weir. The overflow water enters the overflow weir from the lower edge of the bubble barrier to intercept the escaping foam at the end.

③ Intelligent diagnosis expert system, with the ability to self-adjust the operating state.

The intelligent diagnosis expert system is a high-level control system built for modern mines. The system uses PLC to obtain relevant data and signals from the feeding end of the thickener, the internal monitoring end of the equipment and the discharging end. Using built-in algorithms and control logic, the equipment automatically adjusts the operating state by intelligently analyzing the deviation of operating parameters and abnormal working conditions caused by material changes. The intelligent diagnostic expert system makes the production process of HDCY thickener more refined, significantly reduces the risk of low pressure rake, improves the production efficiency of equipment, reduces the labor intensity of on-site posts, and realizes the optimized control, operation and management of the thickener production process.

④ Equipment monitoring and housekeeping system

The device monitoring butler system is a customized product tailored for enterprise leaders and management teams. The cloud platform can realize remote management and operation on mobile terminal devices (mobile phones, Pad, etc.). Including but not limited to report management (report browsing, briefing browsing, general report configuration, intelligent report configuration), alarm management (alarm definition, alarm subscription, historical alarm), data analysis (feed volume, feed concentration, underflow concentration, overflow clarity, torque, etc.), video management (video configuration, video monitoring, video capture), etc., and set corresponding permissions according to the level of terminal users, the system is a product based on cloud architecture and IOT data service design. It has the characteristics of easy expansion, large connection, high performance, fast implementation, safety and reliability.