3results about How to "Lower transmembrane pressure" patented technology

The invention discloses an underwater superoleophobic alumina ceramic microfiltration membrane as well as a preparation method and application thereof, and belongs to the technical field of inorganic ceramic microfiltration membranes and preparation thereof. The problem that an existing aluminum oxide ceramic membrane is not resistant to oil pollution is solved. The nano silicon dioxide is added into an aluminum oxide ceramic sintering system, and the aim of regulating and controlling the pore size of the membrane is achieved by adjusting the liquid phase generation amount in the sintering process by utilizing the characteristics that the silicon dioxide generates a liquid phase in the sintering process and wets the surface of an aluminum oxide crystal and activates crystal lattices under the action of capillary force; the aluminum oxide ceramic microfiltration membrane with the characteristics of small pore diameter and large porosity is obtained, the demulsification capability is good, the interception performance on petroleum ether reaches 90% or above, and meanwhile, the pure water flux can reach 1,300 L.m <-2 >. H <-1 >. Bar <-1 >. And the obtained alumina ceramic microfiltration membrane also has underwater super-oleophobicity, the anti-pollution performance of the ceramic membrane in the operation process is improved, and the transmembrane pressure difference in the filtration process is reduced.

The present invention provides a multi-membrane combined double circulation bioreactor, a multi-membrane combined double circulation biological treatment system and a low carbon-nitrogen ratio organic wastewater treatment method, which belongs to the technical field of wastewater treatment. The multi-membrane combined double circulation bioreactor provided by the present invention has a reasonable structure and can realize double internal circulation. When the low carbon-nitrogen ratio organic wastewater is treated by the multi-membrane combined double circulation biological treatment system based on the multi-membrane combined double circulation bioreactor, no carbon source and phosphorus removal agent are added, and no deep treatment unit is added; at the same time, under the conditions of low energy consumption and low residual sludge production, stable and efficient nitrogen removal and phosphorus removal effects can be achieved; in addition, the amount of suspended sludge and the transmembrane pressure difference can be reduced during the treatment process, the decline of membrane flux can be delayed, the service life and working cycle of the membrane can be extended, and the investment and operation and maintenance costs of the treatment system can be saved.

This application provides a method and system for treating domestic sewage, belonging to the field of sewage treatment technology. The method includes the following steps: S1: The domestic sewage to be treated flows sequentially through an anoxic reaction tank and an aerobic reaction tank, both tanks being filled with multi-metal catalytic functional packing material; S2: The effluent is introduced into a membrane separation tank for sludge-water separation to obtain treated water and sludge; S3: A portion of the sludge generated in the membrane separation tank is returned to the anoxic reaction tank; S4: A portion of the treated water is extracted and introduced into a functional water preparation unit to generate functional water; S5: The functional water is divided into a first path and a second path in a certain proportion, with the first path flowing into the bottom of the membrane separation tank and the second path flowing into the aerobic reaction tank. This invention enhances the nitrogen and phosphorus removal effect through multi-metal catalytic functional packing material, and utilizes the aeration and flushing effect of functional water to alleviate membrane fouling in the membrane separation tank, extending the membrane's service life. The resulting effluent quality is stable and meets current domestic sewage discharge requirements.