Process and equipment for preparing nickel oxide product and recovering hydrochloric acid through nickel chloride solution

Abstract

The invention relates to the technical field of preparing nickel oxide and recovering hydrochloric acid, and in particular relates to a process and equipment for preparing nickel oxide and recovering hydrochloric acid. The equipment comprises a nickel oxide solution tank for recovering waste acid, a waste acid filter, a pre-concentrator, a baking furnace, a furnace top spraying device, burners in tangent distribution, a rotary horizontal mixer, a breaker, a rotary valve, a nickel oxide powder pneumatic conveying and collecting system, a first-stage absorption tower, a second-stage absorption tower, a smoke exhaust fan, a washing tower, a feeding pump sealing as well as cooling water circulating and supplying device, a pyrolysis acid storage tank, a conveying pipeline, a gas and liquid separator, a chimney, a dust extractor, a pneumatic feeding device, a feeding pipeline online cleaning device, a combustion supporting and heating device, a back-flushing flow aiding device, a chlorine removal device and an air purifier. The process and the equipment for preparing nickel oxide and recovering hydrochloric acid have the following advantages that reaction temperature regulating range of the baking furnace is widened, waste gas reaches the discharge standard, equipment utilization rate of the baking furnace is improved, and environmental pollution is avoided.

Description

technical field [0001] The invention relates to the technical field of preparing nickel oxide and recovering hydrochloric acid, in particular to a process and equipment for preparing nickel oxide products and recovering hydrochloric acid using nickel chloride solution. Background technique [0002] During the preparation of nickel chloride, a certain concentration of hydrogen chloride and nickel compounds of 100g / L-140g / L will be produced. During the preparation process, the proportion of hydrogen chloride will gradually decrease, and when it reaches saturation, the dissolution will stop. In order to keep the dissolution process going on, the nickel chloride in the hydrogen chloride should be extracted and the concentration of the acid solution should be reduced at the same time. This just requires a set of process and equipment for preparing nickel oxide or nickelous oxide and recovering hydrochloric acid, sending the HCl solution containing the above ratio to the preparat...

AI Technical Summary

Problems solved by technology

[0004] 1) The existing production process adopts the chemical synthesis method, the production process is long and the cost is high;

[0005] 2) The chlorine-containing waste gas produced in the preparation process needs to be neutralized with alkali, and the sodium hypochlorite produced after neutralization causes secondary pollution to the environment;

[0006] 3) in the crystallization process of nickel chloride, the particle size uniformity cannot be guaranteed to reach more than 85%;

[0007] 4) Due to the generation of chloride ions in the original production process, the equipment of the unit is corroded;

[0008] 5) The open steam heating method is adopted in the crystallization process of nickel chloride, which causes great pollution to the air and the environment;

[0009] 6) The feeding pipeline will form crystals in the pipeline during the working process, causing the pipeline to be blocked. The pipeline must be cleaned regularly. The cleaning and maintenance work is very difficult and the workload is heavy. The pipeline must be disassembled and cleaned manually, which is time-consuming and expensive. , laborious

[0025] 2) Unreasonable discharge method of furnace bottom oxide

The original discharge method is to rely on air back blowing and natural fall of materials. This method is not suitable for the production of non-ferrous metal oxides, because the reaction temperature of non-ferrous metal oxides is very high. The impact of shape, viscosity, etc., can easily cause the outlet to be blocked, and mechanical methods must be used to fundamentally solve this problem;

[0026] 3) The method of preventing the cyclone separator from hanging on the wall and blocking the material is unreasonable. The original discharge is completed by a vibrator installed at the bottom of the cyclone separator. This method not only cannot solve the blockage, but aggravates the blockage. This is due to the low specific gravity and small particle size of the oxide in the cyclone separator;

[0027] 4) The water supply point of the water circulation system cannot achieve circulation

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