H acid: a dye intermediate
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27/02/2005
In India, H-acid (1-amino, 8-napthol, 3,6-disulphonic acid) is manufactured mainly by small and medium-sized enterprises with a production capacity of between ten and 100 tonnes per month. The promotion of such enterprises has created multi-media pollution problems. As the West stopped making toxic dye intermediates, such enterprises mushroomed in industrialising countries.
Due to the usage of high-strength acids and alkalis in the manufacture of H-acid, the combined wastewater stream is contaminated with high chloride and sulphate content. In addition, the presence of toxic naphthalene-based dye intermediates in the wastewater made it non-biodegradable. Effluents from H-acid manufacturing factory are deep red in colour and can contaminate the groundwater in a huge area around the plant if not treated properly.
One such notorious case is that of Bichchri. O P Agarwal set up a chain of chemical factories on the land, situated upstream of Bichchri, on the eastern slopes of a series of hillocks which flank Udaisagar canal. The two H-acid units, Silver Chemicals and Jyoti Chemicals, ruined the groundwater from the only source for at least 400 agricultural families in drought-prone Bichchri. The villagers of Bichchri have not got justice till date. And almost two decades since the factory began, the groundwater in still red coloured in Bichchri.
Due to the usage of high-strength acids and alkalis in the manufacture of H-acid, the combined wastewater stream is contaminated with high chloride and sulphate content. In addition, the presence of toxic naphthalene-based dye intermediates in the wastewater made it non-biodegradable. Effluents from H-acid manufacturing factory are deep red in colour and can contaminate the groundwater in a huge area around the plant if not treated properly.
One such notorious case is that of Bichchri. O P Agarwal set up a chain of chemical factories on the land, situated upstream of Bichchri, on the eastern slopes of a series of hillocks which flank Udaisagar canal. The two H-acid units, Silver Chemicals and Jyoti Chemicals, ruined the groundwater from the only source for at least 400 agricultural families in drought-prone Bichchri. The villagers of Bichchri have not got justice till date. And almost two decades since the factory began, the groundwater in still red coloured in Bichchri.