Patent ID: 6919031
Filing Date: 2005-07-19
Classification: C02F,Y10S

Abstract:
1. A method of treating water or wastewater with both a ballasted flocculation process and a chemical precipitation process for removing suspended solids and contaminants, comprising: a. directing water or wastewater having suspended solids and contaminants into a treatment area; b. mixing insoluble granular ballast material with the water or wastewater to form a mixture; c. subjecting the mixture to mixing and maintaining the insoluble granular material in suspension, and flocculating and aggregating the suspended solids and contaminants around the granular material; d. transferring the mixture and granular material to a sedimentation tank; e. settling the insoluble granular material in the sedimentation tank to form settled sludge and separating clarified effluent from the settled sludge; f. transferring the settled sludge from the sedimentation tank and separating the sludge from the granular material; g. recycling the separated granular material and mixing the separated granular material with the water or wastewater; h. mixing the separated sludge with an alkaline reagent to form an alkaline treated sludge and mixing the alkaline treated sludge with the water or wastewater; i. chemically precipitating contaminants from the water or wastewater as a result of the alkaline treated sludge being mixed with the water or wastewater; j. directing the water or wastewater treated with the alkaline treated sludge to the treatment area; and k. wherein suspended solids and contaminants are removed from the water or wastewater through both ballasted flocculation and chemical precipitation.