Air compressing membrane distillation device and method

Abstract

The invention relates to an air compressing membrane distillation device which is characterized by comprising a hot water tank (1) and a condenser (9), wherein the hot water tank (1) comprises two stage hydrophobic membrane assemblies (5, 7) which are respectively used for millipore aeration of compressed air and water-vapor separation; and the condenser (9) is used for cooling the steam. The invention designs a new membrane distillation process, an air compressing membrane distillation system consists of the two stage hydrophobic membrane assemblies, a mass transfer mechanism directly transfers mass by utilizing an air pressure difference but not a steam partial pressure difference, therefore, the mass transfer efficiency is high. Compared with the air swept membrane distillation, compressed air is filtered by a membrane, thereby water is clean and the produced water quality is good; air is wetted completely, and the air consumption is little. Compared with the direct contact membrane distillation, cold fluid and hot fluid are not directly contacted and condensed at two sides of the membrane, and thereby the energy consumption can be obviously reduced. Compared with the vacuum membrane distillation, the energy consumption of an air compressor is lower than that of a vacuum pump, and the utilization efficiency of electric power is high; and meanwhile, the equipment requirement is simple.

Description

technical field [0001] The invention relates to a compressed gas membrane distillation device and method, in particular to a membrane separation treatment method for water purification treatment and chemical separation. Background technique [0002] Membrane distillation has attracted worldwide attention and research in recent years. Compared with ordinary evaporators, one of the most notable features of membrane distillation is that the evaporation area per unit volume is large, so that the device can be operated efficiently in the normal pressure and lower temperature evaporation process, and the vapor phase space required for distillation operation very small. Compared with reverse osmosis, membrane distillation is a heat-driven process with low operating pressure, so the requirements for membrane mechanical properties are low, equipment costs are also low, and process safety is improved. Moreover, membrane distillation has low operating pressure and high desalination ra...

AI Technical Summary

Problems solved by technology

[0007] However, so far, the above four membrane distillation methods have some problems such as high energy consumption, low efficiency, and low reliability.

For example, although the process equipment of direct contact membrane distillation is simple, due to the direct contact of cold and heat sources, the energy consumption of the equipment is high, and the leakage of hydrophobic membrane is prone to occur; although the membrane flux of vacuum membrane distillation is large, But higher system requirements

Air-gapped membrane distillation and flow-swept membrane distillation have lower throughput

Images