Pressure energy composite type desalination unit

Abstract

The invention provides a pressure energy composite type desalination unit. The pressure energy composite type desalination unit comprises a pressure energy recovering container, a membrane pump subsystem and a liquid feeding and liquid discharging subsystem, wherein the membrane pump subsystem comprises a high-pressure pump M1, a circulating pump M2 as well as a membrane assembly with a pluralityof reverse osmosis membranes which are arranged in parallel; the liquid feeding and liquid discharging subsystem comprises a brine pre-feeding port, a liquid discharging port and a water supply and discharge pump M3 which is used for feeding liquid into the pressure energy recovering container before work and discharging strong brine after work; the circulating pump M2 is set to feed the brine into the membrane assembly from the pressure energy recovering container during work to perform reverse osmosis; the high-pressure pump M2 is set to supplement the brine to the pressure energy recoveringcontainer while the circulating pump works to maintain the system pressure; and the membrane assembly is provided with a total brine inlet, a total fresh water outlet and a total concentrated water outlet which is used for returning the produced strong brine to the pressure energy recovering container. The pressure energy composite type desalination unit integrates reverse osmosis, energy recovery and washing functions, reduces energy consumption, and is compact in structure, small in occupied area, high in water output efficiency and easy to overhaul and maintain; and through timed washing,the unit is low in failure rate and long in life.

Description

Technical field: [0001] The invention relates to the technical field of fluid machinery engineering, in particular to a pressure-energy composite desalination unit. Background technique: [0002] At present, the equipment used in the typical domestic desalination process is mainly composed of lift pumps, ultrafiltration, booster pumps, security filters, high-pressure pumps, energy recovery devices, and reverse osmosis membrane components. The overall structure is complex and occupies a large area. [0003] Moreover, most of the equipment used in the traditional desalination process uses reverse osmosis membranes to work in series. Disadvantages of reverse osmosis membranes working in series with high-pressure pump technology: large space occupation, high capital investment costs; the pressure in the reverse osmosis membrane decreases step by step, the water output of the osmosis membrane decreases step by step, and the separation efficiency is low; the utilization rate of th...

AI Technical Summary

Problems solved by technology

[0002] At present, the equipment used in the typical domestic desalination process is mainly composed of lifting pumps, ultrafiltration, booster pumps, security filters, high-pressure pumps, energy recovery devices and reverse osmosis membrane components. The overall structure is complex and the area is large.

[0003] Moreover, most of the equipment used in the traditional desalination process uses reverse osmosis membranes to work in series

Disadvantages of reverse osmosis membranes working in series with high-pressure pump technology: large space occupation, high capital investment costs; the pressure in the reverse osmosis membrane decreases step by step, the water output of the osmosis membrane decreases step by step, and the separation efficiency is low; the utilization rate of the reverse osmosis membrane is not high. etc., its service life is different; the reverse osmosis membrane is embedded in the same protective tube, which is not conducive to monitoring and maintenance; and, due to the gradual attenuation of energy in the series reverse osmosis process, there will be a brine pressure setting that passes through the first stage membrane Much higher than the osmotic pressure, to ensure that the final membrane is still higher than the osmotic pressure

However, at present, energy recovery devices are mainly imported from abroad, and the cost is relatively high, which will greatly increase the cost of production

Images