Methods for electronic wastewater treatment at an ultra-low concentration of contaminants adapting microfiltration membrane bioreactor process and selective heavy metal removal process

• Main Authors: KIM, JIN HYUN, PARK, SEONG JUN, KIM, JONG WOON, LEE, JIN, KIM, HUN SOO
• Format: Patent
• Language: English; Korean
• Published: 08.02.2017
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATERTREATMENT OR WASTE MANAGEMENT; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The present invention relates to a method for treating contaminants in electronic wastewater to an ultra-low concentration level by using a microfiltration membrane bioreactor process and a selective heavy metal removal process, in which an organic material, a floating material, nitrogen, and phosphorus are treated and also the floating material is separated from microorganism sludge in a microfiltration membrane bioreactor process, and an interfering reaction is prevented from occurring during reaction of a heavy metal removal agent in a subsequent process, thereby enabling multiple types of heavy metals to be treated to an ultra-low concentration level. According to a preferred embodiment of the present invention, provided is a method for treating wastewater containing an organic material, nitrogen, phosphorus and heavy metals in an electronic wastewater treatment process, the method comprising the steps of: (a) collecting generated wastewater in a flow equalization tank; (b) removing an organic material, nitrogen, and phosphorus by passing the wastewater, fed from the flow equalization tank, through a biological treatment tank sequentially including an anaerobic tank, an anoxic tank, and an aerobic tank equipped with a precise filtration membrane; (c) removing heavy metals by mixing the wastewater, treated in the biological treatment tank, with a heavy metal removal agent in a heavy metal treatment tank; (d) flocculating sludge in the wastewater, treated in the heavy metal treatment tank, in a sludge sedimentation tank, removing the sludge, and discharging sludge-free treated water; and (e) removing a fine floating material and a dissolved material by sequentially passing the treated water, from which the sludge has been removed in the sludge sedimentation tank, through a sand filter and an activated carbon filter, and discharging treated water. 본 발명은 정밀 여과막 생물반응 공정에서 유기물, 부유물, 질소, 인을 처리하여 부유물과 미생물 슬러지를 분리하도록 하고 후속 단계에서 중금속 제거제의 반응시 간섭작용이 생기는 것을 방지하여 다종의 중금속을 저농도로 처리할 수 있도록 하는 정밀 여과막 생물반응 공정과 선택적 중금속 제거 공정을 적용하여 전자 폐수 내의 오염물질을 저농도로 처리하는 방법에 관한 것이다. 본 발명의 바람직한 일 실시예는 전자 폐수의 처리공정에서 유기물, 질소, 인 및 중금속이 함유된 폐수를 처리하는 방법에 있어서, (a) 발생된 폐수를 유량 조정조에 수집하는 단계; (b) 유량 조정조에서 공급되는 폐수를 차례로 혐기조, 무산소조 및 정밀 여과막이 구성된 호기조로 이루어진 생물학적 처리조를 거쳐 유기물, 질소, 인을 제거하는 단계; (c) 생물학적 처리조에서 처리된 폐수를 중금속 처리조에서 중금속 제거제를 혼합하여 중금속을 제거하도록 하는 단계; (d) 중금속 처리조에서 처리된 폐수를 슬러지 침전조에서 슬러지를 응집시켜 슬러지를 처리하고 슬러지가 제거된 처리수를 배출하는 단계; (e) 슬러지 침전조에는 슬러지가 제거된 처리수를 모래 필터 및 활성탄 필터를 차례로 거쳐 미세 부유물 및 용존성 물질을 처리하고 처리수를 배출하는 단계;를 포함하여 이루어진다.