Ammonia recycling method and system in APT production process

Abstract

The invention provides an ammonia recycling method and a system in APT production process. The ammonia recycling method comprises following steps: 1, APT crystallization steam is discharged using a centrifugation blower fan, is introduced into a rectifying tower for rectification and condensation of ammonia tail gas to remove most water, and is introduced into a heat exchanger; 2, a three stage solution obtained via ion exchange is directly used for preparing a desorption agent, the rest ammonia nitrogen wastewater is pumped into a stirring tank, an alkali is added for ammonia activation, andgenerated ammonia tail gas is introduced into the heat exchanger; wastewater obtained via ammonia activation is pumped into an air stripping tower, and ammonia tail gas obtained via air stripping is introduced into the heat exchanger; when the ammonia-nitrogen value of obtained air stripping wastewater is detected to be qualified, discharging through a branch pipe is carried out, otherwise, the wastewater is pumped into the air stripping tower for air stripping; and 3, the temperature of the ammonia tail gas is reduced to be lower than 45 DEG C after treatment using the heat exchanger, the ammonia tail gas is introduced into a hydrochloric acid absorbing tower for circulating absorption, and an obtained solution is sent back to the main treatment stream directly for preparation of the desorption agent. The ammonia recycling method and the system are used for comprehensive treatment of ammonia nitrogen wastewater waste gas obtained in tungsten smelting, waste is changed into valuables,the method flow is simple, operation is convenient, the method is easy to control, and cost is low.

Description

technical field [0001] The invention relates to an ammonia recovery process, in particular to an ammonia recovery method and system in the APT production process. Background technique [0002] Due to the incomplete adsorption of ammonia-containing waste gas in the APT crystallization process, most of the ammonia-containing waste gas is difficult to recycle at present. The concentration of concentrated ammonia water recovered directly is low and has no use value, resulting in a large consumption of liquid ammonia and ammonium chloride. [0003] Ammonium paratungstate (APT) is produced through the ion exchange method of tungsten smelting. The ammonia nitrogen waste gas generated during the smelting process is mainly generated from the APT crystallization condensate water and part of the tail gas. The ammonia nitrogen waste water is mainly generated from the ion exchange and APT crystallization process in the APT production process. In the process of tungsten smelting, APT is p...

AI Technical Summary

Problems solved by technology

The specific idea is to make ammonium salt or ammonia water through the method of absorption. Although some methods solve the environmental protection problem, the usable value is not very high, and at the same time, additional costs will be added, making the enterprise uncompetitive.

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