In today’s global environmental protection attaches great importance to the background, sewage treatment has become a crucial task. And filter press as a kind of efficient solid-liquid separation equipment, in the sewage treatment industry plays a pivotal role.
- Working Principle and Advantages of Filter Presses
Filter press mainly separates solid particles from liquid in sewage through pressure. Its working principle is to utilize the filter cloth or other filter media, driven by pressure, so that the solid particles in the sewage are retained on the filter cloth, while the liquid is discharged through the filter cloth. Filter press has the following significant advantages:
- High-efficiency separation: it can quickly and effectively realize solid-liquid separation, with remarkable separation effect, which greatly improves the efficiency of sewage treatment.
- Easy to operate: the equipment has a high degree of automation, simple and convenient operation, reducing the difficulty and workload of manual operation.
- Strong adaptability: it can deal with various types of sewage, including industrial wastewater, domestic sewage, etc. It also has good adaptability to sludge of different nature.
- Energy-saving and environmental protection: low energy consumption in the operation process, and will not produce secondary pollution, in line with environmental requirements.
Second, the application of filter press in different stages of sewage treatment
- Pre-treatment stage
In the pretreatment stage of sewage treatment, the filter press can be used to remove the larger particles in the sewage, such as sand, gravel, branches, etc., to prevent these substances from causing damage to the subsequent treatment equipment. Through the preliminary solid-liquid separation, it can provide better conditions for the subsequent treatment process.
- Biochemical treatment stage
In the process of biochemical treatment, a large amount of activated sludge will be produced. Filter press can dewater these activated sludge, reduce the water content of sludge, reduce the volume of sludge, and facilitate the subsequent disposal and transportation. At the same time, the dewatered sludge can also be used for resource utilization, such as for soil improvement and fertilizer production.
- Deep treatment stage
In the deep treatment stage of sewage treatment, the filter press can be used to remove tiny particles and suspended solids in the water to further improve water quality. For example, before the membrane separation technology, the use of filter press for pretreatment can effectively extend the service life of the membrane and reduce operating costs.
Third, the application characteristics of different types of filter presses in wastewater treatment
- Plate and frame filter press
Plate and frame filter press has the advantages of large filtration area, high filtration pressure and high solid content of filter cake. It is suitable for sewage treatment occasions with large treatment capacity and complex sludge properties. However, its equipment volume is large, installation and maintenance is relatively complex.
- Belt filter press
Belt filter press runs continuously, has large processing capacity and is suitable for processing sludge with high concentration. It is characterized by simple operation and small footprint. However, the dewatering effect is slightly inferior to that of plate and frame filter press.
- Chamber filter press
Compact structure, high filtration efficiency, chamber filter press is suitable for small and medium-sized sewage treatment plants. Its filter plate has high strength and good corrosion resistance, which can adapt to different working environments.
Fourth, the application cases of filter press in foreign sewage treatment industry
In Europe, many countries’ sewage treatment plants widely use filter presses for sludge dewatering. For example, a large-scale sewage treatment plant in Germany, through the use of plate and frame filter press, the water content of sludge from 95% to less than 60%, which greatly reduces the volume of sludge and lowers the transportation and disposal costs. At the same time, the dewatered sludge is used as agricultural fertilizer, realizing the recycling of resources.
In North America, belt filter presses are also widely used in the wastewater treatment industry. A U.S. wastewater treatment plant uses a belt filter press to dewater activated sludge, and the treated sludge is transported to a landfill for disposal. The continuous operation capability and high efficiency treatment capacity of this equipment provide a guarantee for the stable operation of the wastewater treatment plant.
- Future development trend
With the continuous progress of science and technology, the application of filter press in the sewage treatment industry will continue to innovate and develop. In the future, the filter press will be more intelligent, automated, easier to operate and more stable performance. At the same time, the research and development and application of new filtration media will further improve the separation effect and treatment capacity of the filter press. In addition, the combination of filter press and other wastewater treatment technologies, such as synergistic application with membrane separation technology, biological treatment technology, etc., will bring more innovative solutions for the wastewater treatment industry.
In short, the filter press has a wide range of application prospects and important role in the sewage treatment industry. Through continuous technological innovation and optimization, the filter press will make greater contributions to the global environmental protection cause.