Application of Chamber Filter Press in Acidic Wastewater Treatment
Hydrochloric acid is a chemical product widely used in pickling and electroplating of steel and steel structures. It is also used in chemical and rare earth production processes. The amount of hydrochloric acid wastewater generated each year is countless.
If measures are not taken to treat these wastewaters and waste acid liquids, the pollution, damage, and waste of resources to the environment will be very alarming. Now, the treatment of wastewater and waste acid liquid is actually related to the benefits and survival of each production enterprise. Chamber filter presses have outstanding advantages in treating acidic wastewater. The recessed chamber filter press can effectively treat solid impurities in acidic wastewater and reduce the acid concentration of the wastewater through solid-liquid separation technology.
Working Principle of Recessed Chamber Filter Press
The chamber filter press consists of filter plates arranged to create a filter chamber, with recessed sides that combine to form a chamber between every two plates. The surface of the filter plates features convex points that support the filter cloth. Through holes in the center and corners of the filter plates form a complete channel when assembled, allowing the passage of suspension, wash water, and the extraction of filtrate. The filter plates have handles on both sides to support the crossbeam, and a clamping device presses the plates together.
Under the pressure of the feed pump, the material to be filtered is pumped into each filter chamber, where the solid and liquid are separated by the filter medium (with the appropriate filter cloth selected for different industries). A filter cake forms on the filter cloth while the filtrate passes through the cloth and is discharged through the outlet channel. Once filtration is complete, clean water can be introduced to wash the filter cake. Afterward, the filter plates are opened to remove the filter cake, and the filter cloth is cleaned. The filter press is then re-pressed to begin the next cycle.
Chamber Filter Press Treatment Process
Pretreatment: First, the acidic wastewater is collected into a wastewater pool, and alkaline substances (such as lime or sodium hydroxide) are added to the wastewater to neutralize the acidity. The pH value is adjusted to a range suitable for subsequent treatment. Then, flocculants (such as polyacrylamide) are added to aggregate the suspended matter in the wastewater into larger flocs, which is convenient for subsequent solid-liquid separation.
Feed: The pretreated wastewater is pumped into the filter chamber of the filter press. The filter plate of the filter press is covered with filter cloth. The selection of filter cloth needs to be determined according to the acidic characteristics of the wastewater, and usually, a material with strong acid resistance is selected.
Pressure filtration: The hydraulic system applies pressure to force the liquid in the wastewater through the filter cloth, while the solid particles (i.e., filter residue) are trapped on the filter cloth to form a filter cake. The filtered liquid (filtrate) usually flows into the sump.
Unloading the filter cake: After the filtration is completed, the filter press will automatically or manually remove the filter cake. The unloaded filter cake can be dehydrated and dried or sent directly to a dedicated waste treatment facility.
Filtrate treatment: The filtrate is usually further treated chemically, such as neutralization or precipitation, to remove residual acidic substances and metal ions. The treated filtrate can meet the discharge standard or reuse standard.
Equipment cleaning: To maintain the filtering effect, the filter cloth needs to be cleaned regularly, usually using high-pressure water or chemical cleaning agents. During the treatment process, some acidic substances will remain inside the filter press, which needs to be cleaned regularly to prevent equipment corrosion and clogging.
Conclusion
Chamber filter presses are suitable for suspensions with high compressibility or nearly incompressible residues. With the continuous development of Chinese society, the requirements for the environment are getting higher and higher. Environmental protection equipment with superior performance, such as chamber filter presses, will surely play an increasingly important role in the environmental protection industry. Chamber filter presses are a kind of mechanical equipment that can achieve solid-liquid separation very well. In the fields of environmental protection and wastewater treatment, filter presses can reduce water pollution and promote the recycling of water resources. They play an indelible role in the purification of water resources and the recycling of recycled water.