Saline treatment system and method

Abstract

The invention relates to a saline treatment system and method belonging to the technical field of water treatment. A concentrating type solar heater, a steam generator, a vacuum multi-effect distillation device, a saline pump, a fresh water pump, a saline heater, an oil pool, an oil pump and a gas and water separator are used in the system and method. High-temperature heat conducting oil generated by the concentrating type solar heater is respectively conveyed to the steam generator and the saline heater, saline pumped in the saline heater is heated to high-temperature saline and then conveyed to the vacuum multi-effect distillation device, and fresh water pumped in the steam generator is heated to steam and then conveyed to the vacuum multi-effect distillation device. Strong saline is finally discharged. As the saline is heated by the high-temperature heat conducting oil generated by solar energy so as to generate the high-temperature saline, and the cycling utilization fo the steam is formed by utilizing gas and water separation, the steam quantity required by a heat exchange evaporator of the vacuum multi-effect distillation device can be greatly reduced. Furthermore, the evaporation efficiency of the saline can be greatly increased, and equipment investment can be reduced.

Description

technical field [0001] The invention relates to a brine treatment system and a brine treatment method, belonging to the technical field of water treatment. Background technique [0002] In recent years, the shortage of water resources in my country has become very serious. It has become a trend to use salt water (such as sea water or industrial wastewater) to obtain fresh water through desalination. Commonly used methods for desalination of industrial brine are divided into two categories, thermal method (multi-stage flash evaporation, low-temperature multi-effect distillation) and membrane method (reverse osmosis). The thermal method is to use heat energy to cause phase change of brine, evaporate water, and obtain fresh water through condensation. Thermal desalination needs to use steam as a heat source, and a steam generating device (usually a large coal-fired, gas-fired or oil-fired boiler) must be configured, which requires large investment, high cost and high energy co...

AI Technical Summary

Problems solved by technology

Such as the solar compressed air distillation seawater desalination device disclosed in the Chinese patent of publication number CN101723476A, the difference between this device and the Chinese patent of the above-mentioned publication number CN101591042A is that the heat pump is cancelled, the solar energy is transmitted to the seawater through the heat exchanger, and the steam evaporated from the seawater is compressed by a fan ;The device passes the low-temperature seawater heated by solar energy into the negative pressure evaporation chamber to vaporize itself, and then uses the latent heat of steam condensation to heat the seawater in the evaporation chamber, so there are still disadvantages of low evaporation efficiency, low fresh water yield, and impossibility of industrialization

Another example is the seawater desalination low-temperature multi-effect device disclosed in the Chinese patent of Notification No. CN2934211Y. This device wants to use solar energy to generate steam to evaporate seawater, but obviously the efficiency of directly generating steam with solar energy is very low (steam output is small), and it is difficult to continue the evaporation of seawater. need

Another example is the solar desalination equipment disclosed by the Chinese patent of Publication No. CN1417132A. This equipment uses the heat exchanger to generate steam from the working medium heated by the solar energy, and then uses the steam to evaporate seawater through a multi-effect distillation device to obtain fresh water; when the equipment distills seawater, it needs The steam consumption is large, which requires a large-scale investment in solar heaters to meet, so the evaporation efficiency is still low (that is, the fresh water yield is low), and it is difficult to industrialize production

[0006] There is also a common defect in the prior art of each patent illustrated above: since solar energy cannot continuously provide energy, only solar heat collectors cannot guarantee continuous operation of seawater distillation or desalination devices.

[0007] In addition, the concentrated brine produced by the above-mentioned prior art is generally directly discharged (such as discharged into the sea), which not only causes harm to the environment (such as causing changes in the local ecology of the ocean), but also does not fully utilize the salt in the concentrated brine

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