ZJ slurry pump is a centrifugal pump specifically designed for conveying abrasive slurries containing solid particles, where "ZJ" stands for "Impurity Slurry Pump". The pump features:
Structural Design: Single-stage, single-suction cantilever structure. Wet-end components (e.g., impeller, volute, wear plate) are typically made of high-chromium wear-resistant cast iron or wear-resistant rubber, effectively resisting erosion from quartz sand, coal powder, and other particles in coal slurry.
Performance Parameters: Flow range of 50-2000 m³/h and head up to 120 m, suitable for high-flow and medium-high head slurry transportation.
Working Condition Adaptability: Capable of conveying coal slurry with solid content (mass concentration) up to 60%, and has corrosion resistance, adapting to the high-wear and strongly alkaline (coal slurry water pH 7-12) environment in coal preparation plants.
The core processes of coal preparation plants include slurry preparation, separation, dewatering, and coal slurry water recovery, where ZJ slurry pumps play a key role in multiple links:
Raw Coal Crushing and Slurrying:
After crushing, raw coal is mixed with water to form coal slurry. ZJ slurry pumps transport the slurry from the storage tank to separation equipment (e.g., heavy medium cyclones, jig washers). For example, in the heavy medium coal preparation process, the pump delivers the magnetite powder-containing heavy medium suspension to the cyclone at stable pressure to ensure separation accuracy.
Advantage: The high-wear-resistant impeller reduces wear from coarse particles (e.g., gangue, pyrite) in the coal slurry, ensuring continuous transportation efficiency.
Tailings Transportation and Thickening:
The coal slurry water (containing fine coal powder and clay particles) after separation is transported by ZJ slurry pumps to thickening tanks or filter presses. For instance, the pump conveys tailings slurry from the separator to the thickener for solid-liquid separation by gravity sedimentation, reducing the subsequent treatment load.
Circulating Water System:
The supernatant (circulating water) from the thickener is pumped back to the front end of the coal preparation process for water recycling. The pump must adapt to the low solid content and high flow rate to avoid impeller cavitation caused by long-term operation.
In the heavy medium coal preparation process, ZJ slurry pumps are responsible for circulating the medium suspension containing magnetite powder to maintain stable medium concentration. As the medium suspension has high solid content (typically 30%-50%) and magnetite powder is abrasive, the wet-end components of the pump must use high-chromium cast iron to extend service life.
High-Head Transportation Scenarios:
When there is a height difference in the coal preparation plant (e.g., the tailings pond is located at a high place), the high-head characteristic of ZJ slurry pumps meets the requirements for long-distance and high-pressure transportation, avoiding transportation interruptions due to insufficient head.
Emergency Drainage and Cleaning:
During equipment maintenance or failures in the coal preparation plant, ZJ slurry pumps can be used for emergency discharge of coal slurry water or cleaning sediments in sedimentation tanks and pipelines to ensure production safety.
| Advantage Dimension | Specific Performance |
| Wear Resistance | Wet-end components use high-chromium cast iron (e.g., Cr26 material), with wear life 3-5 times longer than ordinary carbon steel pumps, reducing downtime for component replacement. |
| Efficiency and Energy Consumption | Optimized impeller design (e.g., backward-inclined blades, large flow passage structure) with efficiency up to 75%-85%, saving 10%-15% energy compared to similar slurry pumps. |
| Maintenance Convenience | Adopts detachable structure (e.g., split volute, bolt-connected wear plate), allowing maintenance without disassembling the entire pump, shortening maintenance time by over 50%. |
| Working Condition Adaptability | Can flexibly adapt to coal slurry conditions with different solid contents and particle sizes by adjusting impeller diameter, rotational speed, or replacing materials. For example, rubber impellers are selected to reduce wear noise when handling coarse coal slurry with high gangue content. |
Type Selection Key Points: Select the pump model based on parameters such as coal slurry solid content, particle size, and transportation distance. For example, prioritize high-chromium cast iron impellers when solid content >40%, and use wear-resistant rubber impellers when solid content <30%.
Operation and Maintenance: Regularly inspect pump vibration, bearing temperature, and sealing devices (e.g., auxiliary impeller seal, mechanical seal) to prevent slurry leakage or bearing overheating; clean sediments in the impeller and volute quarterly to avoid blockage affecting flow.
Environmental Protection and Safety: The pump body should be equipped with a soundproof cover to reduce operating noise (usually ≤85dB); when conveying toxic or harmful coal slurry water (e.g., containing heavy metals), ensure the sealing system is leak-free to comply with environmental protection discharge standards.
Application Case Reference
A large coal preparation plant (processing capacity 2000 t/h) uses ZJ-150 slurry pumps to transport medium suspension in the heavy medium coal preparation process. The pump parameters are: flow 300 m³/h, head 60 m, impeller material Cr26. Actual operation data shows:
Continuous operation cycle reaches 8000 hours (about 1 year), impeller wear <2 mm, no need for replacement;
Compared with the original ordinary slurry pump, energy consumption is reduced by 12%, saving approximately 150,000 RMB in annual electricity costs;
Due to excellent wear resistance, the number of maintenance times is reduced by 3-4 times per year, increasing production efficiency by 5%.
