1. Screening system layout design

The project is based on the principles of compact layout, reasonable structure, and fully meeting the project progress, quality, safety, and the living needs of employees, as well as environmental protection, to carry out system layout planning and layout. The main contents of planning and layout include: wool storage system, aggregate screening and crushing system, finished aggregate storage system, sewage treatment system, construction roads on site, construction power supply and lighting, construction water supply, machine repair workshop, and screening workshop , offices, living and public facilities, etc.; at the same time, protect the original vegetation, plant flowers and trees reasonably, and keep the site green and clean.

2. Production capacity and equipment selection calculation of each part of the system

2.1. Selection of pre-screening equipment
According to the requirements of wool processing capacity, one vibrating screen is selected as the pre-screening equipment, with a screening capacity of 100~350t/h, which meets the production intensity requirements.

2.2. Selection of main screening equipment
According to the calculation, the wool material processing capacity of the main screening building is 210 t/h, and two sets of vibrating screens are selected as the main screening equipment, and the production capacity of a single unit is 80~240 t/h, which meets the production intensity requirements.

2.3. Selection of crushing equipment

After balance calculation, the crushing equipment needs to be adjusted to crush 150~80mm, 80~-40mm coarse aggregates totaling 37.18t/h, and the crushing equipment is PYT-Z1750 medium-sized cone crusher. Meet production intensity requirements.

2.4. Selection of graded dehydration equipment

According to the balance calculation, the fine aggregate needs to be treated at 57.36t/h, and the spiral classifier is selected for processing. When the spiral speed is 5r/min, the sand return amount per hour is 48.79t/h, and the production capacity of 2 sets is 78.06t/h, which meets strength requirements.

2.5. Selection of stacking equipment

According to the existing conditions of the equipment, the stacker is selected as the stacker, with a storage capacity of 600t/h, which meets the storage requirements for finished aggregate.

3. Design of system supply and drainage system

According to the water conservancy and hydropower project construction organization design manual, it is determined that the water consumption per ton of wool is 1.2t. According to the treatment intensity of wool, it can be known that the water consumption of aggregate sieving and washing is 219.6t/h.

The water intake pumping station adopts a floating boat pump station. The hull size of the water intake floating boat pump station is calculated to be 3 x 7m, and the displacement is 11.59t. The floating boat will float up and down with the change of the water level of the Pushi River. The rocker-type connecting bamboo is used to connect with the main pipeline. . The 125mm pipeline is used to lead to the screening building with a ground elevation of 80.00m, and the height difference is 25m. The calculated water supply pressure meets the water pressure requirements for screening and washing.

The screened waste water flows directly into the concrete drainage ditch in the form of overflow and enters the waste water treatment system.

4. Construction power supply design

The construction power is automatically connected to the established power distribution station from the 1OKV line near the working face, and a vacuum circuit breaker on the column and a 1OKV metering device are installed at the lower pole of the T contact as the on-off switch and high-voltage metering. T connected high-voltage lines to the screening power distribution station, production pumps, and living areas.

Install a 59-630KVA10/0.4KV transformer in the power distribution station. A low-voltage power cabinet is installed in the power distribution room to distribute power and supply power loads. Two S9-630KVA10/0.4KV transformers supply power loads of 601KW and 460KW. A S9250KVA10/0.4KV transformer is installed at the production pump, and the power load is 115KW.

The control system adopts a combination of centralized and decentralized control methods. According to the production process and process requirements, it is divided into four separate interlocking systems, namely wool system, screening and grading system, stockpiling system, and feeding system. Production lighting adopts a combination of centralized and decentralized lighting, and low-voltage lighting is used for wet parts.

5. Practice results

The operation practice shows that the production capacity of the system meets the construction strength requirements of concrete engineering, the quality of the finished materials produced is qualified, the equipment configuration is reasonable and effective, and the crushing gradation adjustment is very convenient. The on-site layout is compact, which is convenient for operation and management. The disadvantage is that due to the large difference between the previous geological survey data of the natural stockyard and the statistics of the actual production, the content of oversized stones larger than 150mm is high, which increases the work intensity of oversized stones and increases the crushing capacity. The production intensity of the stone system increases the production and operation cost of the system. In addition, the environmental protection measures of the whole system are also relatively weak. The production process of the system will generate certain noise, and the screening and washing wastewater will occasionally leak during the treatment process, causing certain damage to the surrounding environment. These should be improved and strengthened in future design and production.