RU95100001A - Method and plant for treatment of sewage to remove suspended fibrous impurities - Google Patents

Abstract

FIELD: chemical technology, particularly, technology of cotton cleaning and production of cellulose nitrates. SUBSTANCE: method is carried out in several stages by flotation. In so doing, a part of treated water is sucked off from the flow, aerated with compressed air in discharge end of pump. Aerated flow is separated in volume into two flows in ratio of 1:2. Smaller flow is directed to the first stage of treatment, and the other flow, to subsequent stages. At all stages, aerated flows are injected with subsequent mixing with sewage water into flotation chambers and foam is removed from chamber by air lift. Installed before flotation chamber is separating tank. Pump is connected with aerator made in the form of vessel furnished with discs with injectors connected with drive by two branch pipes tangential in direction of disc rotation side for introduction of liquid phase. These branch pipes separate the upper part of apparatus with branch pipes from the lower part with disc. Abutted to confuser of flotation chambers, from below, is cylindrical shell forming injector together with nozzle supplying aerated water. Arranged from the top of it is cylindrical shell which is embraced with shell of diffuser of lower base to form annual hollow by smaller diameter of confuser cylindrical shell. Confuser has in its top a branch pipe which forms air lift together with air nozzle. Flotation chambers are grouped in the section by treatment stages. Sections are formed by two vertical and one horizontal partitions separating treatment stages, and chambers are mounted on horizontal partition. EFFECT: higher efficiency of treatment, reduced maintenance costs for water aeration and decreased overall dimensions. a

Claims (1)

The invention relates to the field of chemical technology, in particular, to the technology of ginning and the production of cellulose nitrates. In order to increase the efficiency of wastewater treatment, reduce operating costs for water aeration and reduce the size, it is proposed to carry out wastewater treatment in several stages by flotation. At the same time, part of the purified water is sucked out of the stream, aerated by air pressure in the pressure line of the pump. The aerated stream is divided by volume into two in a 1: 2 ratio, the smaller of which is fed to the first stage of purification, and the second to subsequent stages. At all stages, aerated flows are injected, followed by mixing with wastewater into the flotation chambers, and the foam is removed from the chambers by airlift. In front of the flotation chambers, a separation tank is installed, while the pump is in communication with an aeration apparatus, which is made in the form of a tank equipped with a disk with nozzles connected to the drive by two tangential nozzles for introducing a liquid phase directed towards the rotation of the disk, separating the upper part of the device with nozzles from the lower parts with a disk. A cylindrical shell is attached to the bottom of the flotation chamber’s confuser, forming an injector together with the aerated water supply nozzle, and a cylindrical shell, which is covered by an annular cavity, is surrounded by a lower diffuser shell smaller than the diameter of the cylindrical shell of the confuser, and there is a pipe at its top which together with the air nozzle forms an airlift. Flotation chambers are grouped into sections according to the stages of cleaning, sections are made of two vertical and horizontal partitions separating the stages of cleaning, and the chambers are mounted on a horizontal partition.