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Technical Report

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Suspended solids, dissolved solids, total dissolved solids, effluent, wastewater, wastewater strength, treatment systems, physical-chemical, turbidity, polymers, inorganic salts, flocculating agents, coagulating


Fifty or more individual factorial experiments were designed to study the effectiveness of physical-chemical and micro-biological treatments in removal of suspended and dissolved solids in effluent from potatoes, hominy, dry beans and other vegetables. The wastewaters were obtained from local processing plants and treated with 3 to 5 inorganic salts, 13 polymers, and 3 or more pH levels during 12 months. Also, selected strains of yeast and fungi were used to assimilate the effluent. Individual inorganic salts were more effective on a certain vegetable effluent than others. Polymers (anionic and cationic) were more effective in coagulating suspended solids in combination with salts than either alone. Different polymers and concentrations of polymers in combination with salts were required for each effluent tested. Saccharonyces fibuliger was the most effective yeast for reducing total solids and chemical oxygen demand in potatoes. Actively fermenting systems were capable of 90% or more reduction after centrifugation. The fungi Neurospora sitophila and Trichoderma viride assimilated the total and dissolved solids more rapidly in effluents from potato and hominy processing than any of the other fungi studied.

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