Research on physico-chemical pretreatment of wastewaters from animal-origin waste utilization

Abstract

This paper presents the results of one-year research carried out on the installation built to pretreat post-condensate effluents from the process of thermal pressure destruction of animal originated wastes. This prototype installation of capacity ca 5.0 m3/h consists of two stages of physico-chemical wastewater pretreatment. The first stage is used for the heat pipeline cooling of the raw effluents up to temperature 35-45oC, and for fat and suspended matter flotation with the use of hydrogen peroxide aided by induced air flotation (IAF). The second stage is used to oxidize and deodorize with hydrogen peroxide on coke beds under conditions of permanent effluent circulation. The applied technical solution made it possible to deodorize, defat and eliminate all dispersed substances and to achieve a high level of nitrate(III) nitrogen reduction. This developed process may be used in practice as a physico-chemical stage of pretreatment and deodorization of post-condensate effluents before the stage of their full-scale treatment with biological methods. It may also be applied for partial heat power recovery from raw, hot post-condensate wastewater, and thus may result in growing the profitability of animal- origin waste neutralization.