Automatic Membrane Filter Press for Coal Washing Slurry Dewatering

Challenges in the Generation and Treatment of Coal Washing Slurry

As a vital energy resource, coal typically undergoes a washing process after extraction to remove impurities and enhance quality. During wet coal washing, significant amounts of water are used for separation; fine coal dust, clay particles, and mineral impurities enter the water, creating coal washing wastewater.

As this wastewater enters a thickening tank for sedimentation, solid particles gradually aggregate and settle at the bottom, ultimately forming a high-concentration coal washing slurry (coal slime slurry). This slurry is characterized by high water content, fine particle size, high viscosity, and poor settling properties, yet it contains substantial recoverable fine coal resources. Without effective treatment, it not only causes environmental pollution but also increases transportation and storage costs for enterprises.

Efficient Solid-Liquid Separation of Coal Slurry via Filter Presses

To address the difficulties associated with coal washing slurry treatment, filter presses have become essential solid-liquid separation machine in the coal washing industry. Coal slurry is pumped into the filter press chambers; under pressure, water is expelled through the filter cloth while coal particles are retained within the chambers, gradually forming a coal slime filter cake with reduced moisture content.

Compared to traditional natural sedimentation methods, filter presses achieve superior dewatering efficiency, drastically reducing slurry volume and improving the efficiency of transportation and subsequent utilization. Furthermore, the filtrate (clarified water) can be recycled back into the coal washing process, minimizing water waste and helping coal washing plants achieve environmentally friendly operations.

Enhanced Coal Slurry Dewatering with Automatic Membrane Filter Presses

Automatic membrane filter presses are currently widely used, high-efficiency dewatering devices for treating coal washing slurry. Unlike standard filter presses, automatic membrane filter presses feature a secondary squeezing function. Once the initial filtration cycle is complete, membrane plates expand—driven by compressed air or water—to apply additional pressure to the filter cake, thereby further reducing its moisture content. Its core advantages are reflected in the following aspects:

1. Deep dewatering and low moisture content

Utilizing secondary high-pressure membrane squeezing technology, the system effectively breaks down the bound water on the surface of fine particles, significantly reducing the moisture content of the filter cake. Lower moisture content results in a higher calorific value for the coal slime, enhancing its economic viability for external sales.

2. Clear filtrate enabling a closed-loop wash-water cycle

The filtrate produced by the membrane filter press has an extremely low concentration of suspended solids, allowing it to be directly reused in the coal washing production line. This facilitates a closed-loop water cycle, drastically reducing the need for fresh make-up water and minimizing the risk of wastewater discharge, thereby meeting increasingly stringent environmental regulations.

3. High level of automation and strong processing capacity

The automatic membrane filter press can be equipped with features such as an automatic plate-shifting system, an automatic discharge system, and a filter cloth washing system. These features enable fully automated operation—covering filtration, squeezing, and discharge—which significantly boosts filtration efficiency.

As a highly efficient, energy-saving, and eco-friendly solid-liquid separation device, the automatic membrane filter press not only effectively addresses wastewater treatment challenges but also recovers valuable coal slime resources, delivering both economic and environmental benefits. As a professional manufacturer of filter presses, Quanhong Filtration is dedicated to providing global clients with customized dewatering solutions for coal washing slurry; please contact us for a professional quote.