Prevention and control of dimethylamine vapors emission: Herbicide production plant

Abstract

The widely used herbicide, dimethylamine salt of 2,4-dichlorophenoxy acetic acid (2,4-D-DMA), is usually prepared by mixing a dimethylamine (DMA) aqueous solution with a solid 2,4-dichlorophenoxy acetic acid (2,4-D). The vapors of the both, reactants and products, are potentially hazardous for the environment. The contribution of DMA vapors in overall pollution from this process is most significant, concerning vapor pressures data of these pollutants. Therefore, the control of the air pollution in the manufacture and handling of methylamines is very important. Within this paper, the optimal air pollution control system in preparation of 2,4-D-DMA was developed for the pesticides manufacturing industry. This study employed the simple pollution prevention concept to reduce the emission of DMA vapors at the source. The investigations were performed on the pilot plant scale. To reduce the emission of DMA vapors, the effluent gases from the herbicide preparation zone were passed through the packed bed scrubber (water scrubbing medium), and the catalytic reactor in sequence. The end result is a substantially improved air quality in the working area, as well as in the urbanized areas located near the chemical plant.