In industrial production, "substandard clear liquid requiring secondary treatment" and "high moisture content in filter cakes causing a surge in transportation/disposal costs" are common solid-liquid treatment challenges. Filter presses fundamentally solve this problem through their unique filtration and pressing design.
- High-Precision Filtration: Trapping Fine Impurities to Ensure Direct Usability of Clear Liquid
Traditional separation equipment (such as sedimentation tanks and centrifugal filters) has limited ability to trap fine particles (particle size < 1μm), which easily leads to excessive suspended solids (SS) in the clear liquid. This requires additional investment in secondary treatment equipment like sedimentation tanks and filter tanks, increasing costs and occupying more space.
Filter presses achieve high-precision separation through a composite filtration structure of filter cloth and filter plates:
The filter cloth is made of high-density woven materials (such as polyester and polypropylene microporous filter cloth), with pore sizes that can be precisely controlled between 0.1-10μm. It can trap fine impurities such as catalyst particles, sludge colloids, and mineral slurry fines. After filtration, the SS content in the clear liquid is usually ≤ 10mg/L, which is far lower than the national industrial wastewater discharge standard (generally requiring SS ≤ 50mg/L).
For high-viscosity and easily clogging materials (such as starch slurry in the food industry and resin waste liquid in the chemical industry), filter presses adopt a "static filtration + progressive pressure application" mode. This avoids filter cloth clogging caused by high-speed material flow during filtration and ensures stable filtration efficiency. For example, a resin factory uses a filter press to treat resin waste liquid with a viscosity of 2000cP; the light transmittance of the clear liquid reaches over 95%, which can be directly reused in production without secondary treatment.
High moisture content in filter cakes is a "hidden cost" in industrial solid waste treatment. Taking sludge treatment as an example: compared with sludge with a moisture content of 50%, sludge with a moisture content of 80% has a volume nearly twice as large, transportation costs 1.5 times higher, and energy consumption during incineration increases by more than 30%.
Filter presses achieve deep dewatering through a high-pressure pressing system (mainly hydraulically driven), with core advantages as follows:
The pressing pressure can be adjusted according to material properties (usually 0.8-3MPa, and up to 5MPa under special working conditions). For instance, in the mining industry, when treating coal slime with high-pressure pressing at 2.5MPa, the moisture content of the filter cake can be reduced to below 25%, meeting the "dry stacking" standard and eliminating the need for further drying. In the environmental protection industry, when treating municipal sludge, after pressing at 1.5MPa, the moisture content of the filter cake can be controlled below 50%, satisfying the environmental requirements for incineration or landfilling.
For materials that are difficult to dewater (such as printing and dyeing sludge, chemical sludge), some filter presses are equipped with diaphragm filter plates. By injecting high-pressure water or compressed air into the diaphragm, a "secondary extrusion" is applied to the filter cake to further squeeze out the interstitial water inside the cake. This reduces the moisture content of the filter cake by an additional 5%-10% compared to ordinary filter plates.
Take a printing and dyeing factory as an example: after using a diaphragm filter press to treat printing and dyeing sludge, the moisture content of the filter cake decreased from 65% (achieved by traditional plate-and-frame filter presses) to 52%. This reduced the daily sludge transportation volume by 12 tons and saved over 800,000 yuan in annual transportation costs.
The "energy consumption costs" and "maintenance costs" of industrial equipment are often overlooked. Especially for solid-liquid treatment equipment operating continuously 24 hours a day, long-term high energy consumption and frequent maintenance can significantly erode corporate profits. Through optimized structure and operating logic, filter presses achieve the dual advantages of "low energy consumption + low maintenance".
Low-Energy Operation: Consuming Energy on Demand, Saving Over 30% More Energy Than Traditional Equipment
Traditional separation equipment (such as centrifuges and vacuum filters) requires continuous high-speed operation or maintenance of high vacuum, resulting in persistently high energy consumption. Taking sludge dewatering with a processing capacity of 10m³/h as an example: the average daily energy consumption of a centrifuge is about 150 kWh, while a filter press only needs 80-100 kWh, showing a significant energy-saving effect.
Low-Maintenance Design: Durable Components + Simple Operation to Reduce Downtime and Labor Costs
In industrial production, one hour of equipment downtime may cause production losses of tens of thousands of yuan, and complex maintenance processes will further increase labor costs. Filter presses reduce the frequency and difficulty of maintenance through "durable components + simplified structure".
The solid-liquid treatment operating conditions vary significantly across different industries (e.g., temperature, corrosiveness, material viscosity). Traditional equipment often fails to adapt due to "one-size-fits-all" designs, resulting in low separation efficiency and frequent equipment damage. Through "material customization + structural adjustment", filter presses can cover nearly all industrial solid-liquid treatment scenarios.
The reason why filter presses have become a key equipment for industrial solid-liquid treatment lies in their "demand-oriented" design logic:
- To address the pain point of "incomplete separation", they achieve "qualified clear liquid + filter cake reduction" through high-precision filter cloth and high-pressure pressing;
- To tackle the pain point of "high energy consumption & high maintenance", they realize "low energy consumption + low maintenance costs" via intermittent energy consumption and durable components;
- To solve the pain point of "difficulty in adapting to operating conditions", they cover the needs of multiple industries through material customization and structural adjustment.
For industrial enterprises, choosing a filter press is not just about solving a single solid-liquid treatment problem; it is more about achieving the multiple goals of "cost reduction, quality improvement, and compliance" through the dual advantages of "... separation + low-consumption operation". Whether it is sludge reduction in the environmental protection industry, waste liquid recycling in the chemical industry, or concentrate dewatering in the mining industry, filter presses can become key equipment that drives the improvement of production efficiency and green development.
