What is the working principle of zero discharge of wastewater in Shaanxi?

Forced circulation compression steam crystallizer: Forced circulation compression steam crystallizer is the crystallization system with the highest thermal efficiency, and the heat energy required by the system is provided by electric steam compressor. Its main working procedures are as follows:

(1) Pump the concentrated salt to be treated into the crystallizer.

(2) After mixing with the circulating brine, it enters the shell-and-tube heat exchanger. Because the heat exchanger tube is full of water, the brine will not boil under pressure, and the scale in the tube will be suppressed.

(3) The brine in the circulation enters the steam at a specific angle, resulting in vortex, and a small part of the brine is evaporated.

(4) When water evaporates, crystals are produced in brine.

(5) Most of the brine is circulated to the heater, and a small amount of water is pumped into the centrifuge or filter to separate the crystals.

(6) The steam passes through a demister to remove attached particles.

(7) The steam engine is pressurized by the compressor, and the compressed steam condenses into distilled water on the shell of the heat exchange tube of the heater, and at the same time releases the salt water in the heat exchange tube.

(8) After the distilled water is collected, it can be used in the process flow that the factory needs high-quality distilled water. Under some conditions, the crystals produced by crystallizer are chemical products with high commercial value.