What are good ways to deal with high levels of nitrogen trichloride?

Starting from the source, our factory used polyacrylamide as a flocculant in the salt-chemical processing step before; now we use sodium polyacrylate instead. As a result, much less nitrogen trichloride is produced from liquid chlorine, and the latter also provides a better flocculation effect

1. Start with saltwater and control its ammonia content. 2. Increase the frequency of nitrogen trichloride emissions in the liquid chlorine process; based on the analysis of the observation results, levels below 50PPm are safe. Mine is usually less than 20PPm

The generation of nitrogen trichloride can be controlled through aspects such as the operating procedures in the process flow of raw materials and auxiliary materials. The process controls and preventive measures are as follows: 1 Control of raw materials and auxiliary materials 1.1 Control of raw salt Avoid contamination of the raw salt by ammonium-containing substances during transportation, stacking, and storage. 1.2 Control of brine: Control the water quality of water injected into underground salt mines to prevent the brine from containing ammonia. 1.3 Control of saline water: When using river water to produce saline solutions, especially during the season when chemical fertilizers are used in rural areas, it is necessary to closely monitor the pollution caused by these fertilizers to the water body, in order to prevent the saline water from containing ammonia. 1.4 Control of refining agents During the process of refining saline water, it is necessary to control the addition of refining agents to prevent the introduction of ammonium-containing substances. 2 Process Flow Control 2.1 Control of brine parameters: Inorganic ammonium ≤ 1 mg/L, total ammonium ≤ 4 mg/L (after secondary purification of the ion-exchange membrane electrolysis brine, the total ammonium level is generally “0”). 2.2 Addition of sodium hypochlorite: Sodium hypochlorite is added to the refined brine to remove ammonium, and compressed air is used to blow it away. 2.3 Cooling and washing process using chlorine water: A plate-type (Ti) heat exchanger is used to cool the chlorine water, which is then used to directly wash the wet chlorine gas produced by the electrolyzer (to purify the chlorine gas).