Comprehensive recovery method for heat energy and water from printing and dyeing industry wastewater and heat-exchanging system

Abstract

The invention discloses an integrated recovery method and a heat exchanger for the heat energy and water in the wastewater of the printing and dyeing industry. The invention belongs to the technical field of the wastewater treatment in the printing and dyeing industry. The integrated recovery method for the heat energy and water in the wastewater of the printing and dyeing industry comprises the following steps: dividing the printing and dyeing wastewater emitted by a workshop into three types, namely normal temperature water, moderate temperature water and high temperature water, and treating the three types of water separately; after respectively removing impurities through filtration treatment, leading the moderate temperature wastewater and the high temperature wastewater into a high efficiency heat exchange device to carry out the heat exchange with a cold water source and increase the temperature of the cold water source in advance before the cold water source enters a boiler heating room, simultaneously reducing the temperature of the hot wastewater, mixing the high temperature wastewater and moderate temperature wastewater undergoing the heat exchange with the normal temperature wastewater, and then leading the water into a subsequent membrane treatment system for treatment; and taking the membrane system penetrating water and fresh compensation water together as the cold water source which is sent to the high efficiency heat exchange device, and realizing the emission up to the standards after the treatment of the enriched water. The invention can not only reclaim heat energy, but also have the advantages of energy conservation and emission reduction, improvement of equipment service life, convenient equipment maintenance, and the like.

Description

technical field [0001] The invention discloses a method for comprehensively recovering heat energy and water in waste water in the printing and dyeing industry and a heat exchange device, belonging to the technical field of waste water treatment in the printing and dyeing industry. Background technique [0002] my country is a big country in textile printing and dyeing, and textile printing and dyeing is a major player in the discharge of industrial wastewater, accounting for about 80% of the entire industrial wastewater discharge. According to incomplete statistics, the discharge of printing and dyeing wastewater in my country is about 3×10 per day 6 ~4×10 6 m 3 At the same time, textile printing and dyeing wastewater is one of the more difficult industrial wastewater to treat. Every ton of printing and dyeing wastewater discharged can pollute 20 tons of clean water. At present, the water consumption of domestic printing and dyeing factories is generally higher than that ...

AI Technical Summary

Problems solved by technology

Because in the printing and dyeing process, it is necessary to heat the water at room temperature to a certain temperature and then transport it to the production line for production and use, and the discharged high-temperature wastewater contains a lot of heat energy. If it is not used, it will cause a waste of resources.

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