Device and process for comprehensive utilization and resourceful treatment of impurity-containing ammonium chloride wastewater

Abstract

The invention provides a device and a process for comprehensive utilization and resourceful treatment of impurity-containing ammonium chloride wastewater. The method comprises steps: adding calcium hydroxide, carrying out an ammonium chloride reaction to produce free ammonia and calcium chloride, carrying out steam stripping deamination to recover ammonia in wastewater so as to prepare 20% ammoniawater, recycling, removing impurities from the deaminated wastewater, and filtering to recover heavy metal hydroxides; adding a sodium sulfate solution into the impurity-removed wastewater, settlinga calcium salt, and continuously evaporating and concentrating the impurity-removed wastewater. The invention also provides a device for comprehensive utilization and resourceful treatment of the impurity-containing ammonium chloride wastewater. The device comprises a first reaction device, a steam stripping deamination device, a first filtering device, a first pH adjusting device, a second reaction device, a second filtering device, a second pH adjusting device, a first evaporation concentration device, a boiling granulation device, a second evaporation concentration device, a cooling crystallization device and a drying device, according to the invention, resourceful treatment of wastewater can be realized by adopting different schemes, and the method has great social benefits and economic benefits.

Description

technical field [0001] The invention relates to a resourceful treatment method of ammonium chloride wastewater, in particular to a device and process for comprehensive utilization and resourceful treatment of ammonium chloride wastewater containing impurities. Background technique [0002] Ammonia nitrogen wastewater is often produced in chemical, metallurgical and electronic industries, which is an important source of pollution. The ammonium salt contained in ammonia nitrogen wastewater is generally ammonium sulfate or ammonium chloride. Once it is discharged into the water body, especially the slow-flowing lakes and bays, it is easy to cause a large number of algae and other microorganisms in the water to multiply, which is the cause of eutrophication in the water body. One of the main reasons. Among them, ammonia nitrogen wastewater containing heavy metals is particularly harmful. Since ammonia has complexation with most heavy metals, it cannot be removed by simple filtr...

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Problems solved by technology

[0004] The above scheme is ammonium chloride evaporative crystallization, the energy consumption of evaporative crystallization is high, the equipment is easy to corrode, the failure rate is high, and there are many impurities in the wastewater, especially some ammonium chloride wastewater contains heavy metals, such as nickel, cobalt, rare earth, and some chlorine Ammonium chloride wastewater contains magnesium and calcium, resulting in ammonium chloride by-product impurities exceeding the standard, making it difficult to sell

And scheme 2 adds sodium hydroxide and ammonium chloride waste water to react to generate sodium chloride and ammonia, strips ammonia and reclaims 20% ammoniacal liquor, and still liquid evaporates and crystallizes to obtain chloride crystal, but because there are many impurities in the waste water, lead to sodium chloride The quality of the crystal is difficult to meet the standard, and it is difficult to sell

And this method adds a large amount of liquid caustic soda, causes operating cost too high

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