Cyclic utilization method of ammonia gas in production process of ammonium paratungstate

Abstract

The invention discloses a cyclic utilization method of ammonia gas in a production process of ammonium paratungstate. The method comprises the specific steps: firstly, connecting a crystallization boiler in the production process of the ammonium paratungstate with a discharging hole of a rotary furnace in a yellow and blue tungsten manufacturing process in parallel; conveying the ammonia gas generated in two devices into a rectifying tower and a condensation system by utilizing an induced draught fan and carrying out gas-liquid separation to obtain the ammonia gas; spraying and adsorbing most of the ammonia gas with hydrochloric acid, so as to obtain an ammonium chloride solution; pumping the ammonium chloride solution into a venturi device; meanwhile, transmitting the residual ammonia gas into the venturi device to obtain a mixed solution of ammonia water and ammonium chloride; cooling the mixed solution and preparing according to desorption agent concentration requirements needed by ion exchange, so as to realize the cyclic utilization of the ammonia gas in the production process of the ammonium paratungstate. The method disclosed by the invention is safe and environmentally friendly and has less investment and rapid effect; the ammonia gas discharged in the production process of the ammonium paratungstate can be completely recycled, so that zero storage and zero consumption of liquid nitrogen are realized.

Description

Technical field [0001] The invention belongs to the field of tungsten smelting and processing, and specifically relates to a method for recycling ammonia in the process of producing ammonium paratungstate. Background technique [0002] Tungsten is a metal element with an atomic number of 74 and an atomic weight of 183.84. Elemental tungsten is steel-gray or silver-white, with high hardness and high melting point, and is not corroded by air at room temperature; it is mainly used to manufacture filaments, high-speed cutting alloy steels and super-hard molds, as well as optical instruments and chemical instruments. [0003] Tungsten is a non-ferrous metal and an important strategic metal. Tungsten ore was called "heavy stone" in ancient times. In 1781, the Swedish chemist Karl Wilhelm Scheler discovered scheelite and extracted a new element acid-tungstic acid. In 1783, it was discovered by the Spanish De Purya that wolframite also extracted tungstic acid. In the same year, tungsten p...

AI Technical Summary

Problems solved by technology

On the one hand, the internal pressure of the liquid ammonia storage will increase after being exposed to fire or heat, and there is a risk of cracking and explosion; on the other hand, the mixture of ammonia and air will form an explosive mixture. Once leakage occurs, it is not only difficult to recover, but also It will also seriously pollute the environment and cause great harm to the surrounding population.

Therefore, a large amount of storage of liquid ammonia is like storing a "bomb" for enterprises, and there is a great potential safety hazard. Recycling, if the existing processing technology can be improved, will have huge economic, safety and environmental value