COMPLIANCE INFO_1992 - 2012 - Laserfiche WebLink

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. A7iAC-:'TNT QFSrRIPTION OF PRETREATHFNT SYSizr c This system is designed to receive selected waste streams of plating and cleaning rinses from the metal processing area, at a maximum flow rate of 40 cpm and remove metals to a level required by federal 1 pretreatment requirements . Concentrated dumps will be transferred to a collection/ feed tank and metered into the rinse stream to prevent overwhelming the system 's treatment capacity. The rinse water will be directed to a in-ground sump for collection. The collected liquor will then be pumped to an above ground pre-treatment system for further processing . The first stage of the pre-treatment process will include a pH adjustment system controlled by a panel mounted pH meter connected to a PH probe in the treatment station. The probe will sense the pH of the incoming liquor and initiate the flow of lime necessary to maintain a pH of 8 . 0 - 8 . 5 in the reactor vessel . The pH adjustment process will precipitate the insoluble metallic hydroxides and then overflow to the second stage of the treatment process , flocculation. Flocculation is necessary to coagulate the precipitated metallic hydroxide to a larger particle for more efflcient settling . This is accomplished by the addition of organic polymer, and slow mixing of the liquid to prevent disassociation of the coagulate once formed . The polymer feed system will feed a liquid polymer into a water filled system for mixing and injection into the flocculation reactor . After coagulation, the liquor will overflow to a clarifier in which the coagulated particles will settle to the bottom and clear water- will, overflow to the sewer . Sludge collected in the clarifier will be removed by an automatic sludge withdrawal system operating from two ( 2 ) timers. The first. tr is utilized to control the frequency of sludge removal . The second , initiated by the first timer, is utilized to control the duration or' the sludge removal process . Duration control is necessary to provide more efficient sludge removal . The sludge once removed will be transferred to a thickener in which it will =compress to approximately 5 - 8 S by weight solids . The thickening of the sludge is necessary for more efficient sludge dewatering by the filter press . Sludge dewatering is accomplished by pumping the thickened sludge at a high pressure through a recessed plate filter press. The sludge will be retained to form a semi-dry cake approximately 40 - 50 % by weight solids . The dry cake will be manually removed and transferred to a holding container for disposal to an approved landfill. The filter press has 4 cubic foot capacity with an automatic Opening and closing device. This 4 cubic foot dry cake will be collected irr a 5 cubic foot rolling dumpster to transfer the sludge from the press to the holding container . All control instruments will have an audible alarm with flashing lights to signal an out of control condition of high level in the tanks .