A pressing method of variable capacity filter press

Abstract

The invention discloses a squeezing method of a variable-volume press filter. The squeezing method comprises the following steps: pre-pressing, feeding, primary squeezing and dehydration and secondary squeezing and dehydration, wherein the secondary squeezing and dehydration process comprises a plurality of segmented squeezing and dehydration, each segmented squeezing and dehydration process comprises the following steps: maintaining pressure and dehydrating for certain time under the squeezing pressure value set in the segment, wherein squeezing pressure is reduced due to dehydration of squeezed objects, when the squeezing pressure value is reduced to a set pressure difference, a hydraulic cylinder acts to achieve the set squeezing pressure value to be continuously squeezed and dehydrated until set squeezing time at the segment is reached, then entering the next segmented squeezing and dehydration process until all the squeezing and dehydration time of all segments are over, then the next squeezing and dehydration process is allowed, and the squeezing pressure values in the squeezing and dehydration process of all segments are gradually increased from front to back. The squeezing method has the significant advantages that the material dryness is large, the internal and external dryness are consistent and the dehydration efficiency is high.

Description

technical field [0001] The invention relates to a filter press dehydration technology, in particular to a press method of a variable capacity filter press. Background technique [0002] The variable capacity filter press is a kind of equipment with better dehydration effect for dehydration of materials, especially for the dehydration of sludge from sewage treatment. However, in the past, this kind of equipment would use a method of pressing the sludge for a certain period of time to squeeze the sludge. This squeezing method works better for materials that are easy to dehydrate, but for materials that are not easy to dehydrate (such as municipal sludge, chemical industry, etc.) sludge), the surface layer of the sludge cake in the filter plate of the variable capacity filter press will have a high dryness, while the dryness of the middle part is low, that is, the filter cake appears "dry on the outside and wet on the inside". Even if the pressing force is increased and the pr...

AI Technical Summary

Problems solved by technology

However, in the past, this kind of equipment would use a method of pressing the sludge for a certain period of time to squeeze the sludge. This method of squeezing is better for materials that are easy to dehydrate, but for materials that are not easy to dehydrate (such as municipal sludge, chemical industry, etc.) sludge), the surface layer of the sludge cake in the filter plate of the variable capacity filter press will have a high dryness, while the dryness of the middle part is low, that is, the filter cake appears "dry on the outside and wet on the inside". Even if the pressing force is increased and the pressing time is extended, due to the high density of the outer layer, it is difficult for the inner moisture to come out, and it is still difficult to get rid of the defect of "dry outside and wet inside" of the filter cake

Images