Detailed Process Flow Explanation

Stage One: Feeding Distribution and Pre-washing Screening

• Raw materials are conveyed from the feeding hopper via belt to the distributor, evenly split into two and then sent to 2 groups (total 4 units) of horizontal vibrating screens.
• Synchronized spray water supply: about 20% clean water (from clean water pool) + 80% recycled water (from XS6000 wheel washer and ZS2430 dehydration screen discharge) jointly sprayed onto the vibrating screen.
• Through the high-frequency excitation of the vibrating screen combined with a large amount of water flow, impurities and large stones are quickly removed, and sand flows with water to the next stage.

Stage Two: Intensive Scrubbing and Primary Dehydration

• Sand and wastewater enter the 2LH1575 double spiral sand washer, where rotating spiral blades scrub deeply to remove adhering soil.
• Washed sand is discharged to the ZS2424 dehydration screen for primary dehydration, then falls into an equipped water tank for temporary storage.

Stage Three: Fine Sand Recovery and Wastewater Separation

• Mud sand water overflowing from the side overflow trough of the spiral sand washer, together with wastewater discharged from the ZS2424 dehydration screen, flows into the BT800 fine sand recovery machine.
• Fine sand is concentrated and dehydrated by cyclone and returns to the equipped water tank; tail water is discharged by the cyclone into the sewage pool for subsequent water treatment.
• At this point, the mud content in the sand in the water tank has dropped to about 10%.

Stage Four: Fine Washing Purification and Final Dehydration

• About 80% proportion of clean water (from clean water pool) is injected into the equipped water tank for secondary high-intensity washing.
• Material overflows into the XS φ6000 wheel sand washer, where the impeller rotates and tumbles to further remove residual mud powder.
• Washed sand is scooped out by the impeller and sent to the ZS2430 dehydration screen for final dehydration, producing high-quality finished sand.

Stage Five: Closed-loop Water Circulation

• Overflow water from the wheel washer and discharge from the ZS2430 dehydration screen are pumped back to the horizontal vibrating screen, forming an efficient closed-loop washing circuit.
• 80% of the water is reused, maximizing reduction of clean water consumption and wastewater discharge, significantly improving economic and environmental benefits.

Core Water Circuit Design Concept

Two-level differentiated water use strategy

• Pre-washing stage (vibrating screen): mainly recycled water, carrying out coarse separation and preliminary washing functions.
• Fine washing stage (wheel washer): mainly clean water, ensuring the cleanliness of finished sand meets standards.

Efficient Circulation and Reuse

• About 80% of water is recycled and reused, with low clean water replenishment and low wastewater generation.
• Through precise water distribution and diversion design, the maximum amount of finished sand is washed with the minimum amount of clean water.

Efficient Fine Sand Recovery

• The BT800 fine sand recovery machine uses cyclone concentration technology, achieving a fine sand recovery rate of up to 95%, greatly reducing product loss and tail water load.

Technical Performance Indicators

Core Advantages of the Process

① High Recovery, Low Emission

• Fine sand recovery rate reaches 95%, effectively reducing resource loss.
• Two-stage water circulation design uses less clean water and produces less wastewater, significantly reducing water treatment costs (chemicals, labor, equipment depreciation).

② Efficient and Streamlined Equipment

• Short process chain and high single-machine efficiency reduce the number of equipment units by more than 30% compared to traditional solutions for the same output.
• Less civil construction investment, compact footprint, shortened initial construction period, and rapid production ramp-up.

③ Stable Operation and Easy Maintenance

• Smooth process flow and high automation level allow for streamlined operator staffing.
• Equipment maintenance is convenient with short downtime, truly achieving low cost, high output, and high stability.

④ Environmental Compliance

• High water recycling rate meets urban environmental protection and zero direct discharge trends.
• Low wastewater volume; subsequent supporting sedimentation tanks, thickeners, or filter presses can achieve standard discharge or dry stacking treatment.

Application Recommendations and Precautions

1. Raw Material Testing: It is recommended to measure the mud content, MB value (methylene blue value), and 0.075 mm passing rate of raw materials before startup to fine-tune the clean water ratio and spray points.
2. Water Pool and Pump Station Configuration: Clean water pools, wastewater pools, and return water pumps should be designed with redundancy for a peak flow of 1000 m³/h to ensure stable operation during rainy seasons and fluctuating conditions.
3. Agglomerated Mud Block Treatment: If the proportion of agglomerated mud blocks in raw materials is high, a drum stone washer or strong scrubbing unit can be added at the front end to further improve the primary washing effect.
4. Subsequent Water Treatment: It is recommended to equip with thickening tanks plus plate and frame filter presses or screw dewatering machines to achieve dry stacking of mud cakes and reuse of clean water, meeting zero or near-zero discharge standards.

Summary

This production line adopts a four-stage linked process of "pre-washing screening → scrubbing recovery → fine washing purification → final dewatering," combined with two-stage differentiated water use and efficient closed-loop circulation. Under high mud and impurity conditions, it achieves high recovery, low emission, low cost, and high quality.

The equipment configuration is streamlined and efficient, the process design is scientific and ingenious, and the operation is stable and reliable. It is an ideal sand washing solution for complex raw materials such as urban shield soil and foundation soil, fully meeting the dual demands of environmental protection and high-quality construction sand in the Nanshan area of Shenzhen.