A new processing method and device for producing polyvinyl alcohol powder

Abstract

The invention relates to a novel processing method and device for producing polyvinyl alcohol powder and belongs to the field of polyvinyl alcohol production. The method includes: PVA powder mother liquor generated after alcoholysis during polyvinyl alcohol production enters a precipitation tank from an alcoholysis machine and an extruder, is stirred by the precipitation tank and enters a mother liquor filtering machine, the solid-liquid mixture in the filtering machine is fed into a byproduct centrifuge to perform solid-liquid separation, solid is fed into a drying machine for drying, and packaging is performed. The device comprises the alcoholysis machine, a crusher, the extruder, the drying machine, a spiral conveyor, a vibration screen, a stock bin pneumatic conveying pipeline, the precipitation tank, a distribution liquid adding pump, a mother liquor delivering pump, a cyclone separator, a mother liquor filtering machine, a stock solution tank, a methanol condensing tower, a byproduct drying machine, a byproduct conveyor, a vibration screen, a packaging machine, the byproduct centrifuge, a centrifuge, a defoaming agent storage tank and a defoaming agent adding pump which are connected through pipelines. By the novel processing method and device, polyvinyl alcohol production cost is lowered, environment pollution is reduced, and potential safety hazard is eliminated.

Description

technical field [0001] The invention belongs to the technical field of polyvinyl alcohol production, in particular to a method and device for processing PVA powder in the production process of polyvinyl alcohol. Background technique [0002] In the existing production process of polyvinyl alcohol, the alcoholysis unit mother liquor process is as follows: the alcoholysis mother liquor extruded by the screw extruder contains a small amount of PVA powder, and after entering the sedimentation tank, the PVA powder is precipitated and settles down at the bottom of the sedimentation tank The PVA powder is sent back to the inlet of the screw extruder through the distribution liquid pump to recover the PVA therein. The supernatant liquid in the sedimentation tank is sent to the alcoholysis mother liquor storage tank in the intermediate tank area after being filtered by the mother liquor delivery pump and the mother liquor filter. At present, the two columns of the sedimentation tank...

AI Technical Summary

Problems solved by technology

[0003] In order to ensure product quality, the PVA powder in the sedimentation tank is currently discharged from the manhole and discharge port during maintenance, which is labor-intensive and time-consuming, resulting in increased methanol consumption, unqualified wastewater discharge, and potential safety hazards

The PVA powder discharged from the mother liquor filter is too wet and contains methanol, which is not conducive to bagging, storage and sales. The PVA powder discharged from the mother liquor filter is used as waste in the production process of polyvinyl alcohol, and has been stored in the open until a certain amount is sold. Methanol is highly volatile, and the concentration of methanol in the storage location is high. In addition to potential safety hazards, it will also cause environmental pollution

Images