Browse > Article

Thickening and Dewatering of Municipal Wastewater Sludge : Separate and Combined Treatment of Primary and Secondary Sludge  

Lee, Jin-Woo (Dohwa Consulting Engineers Co., Ltd.)
Choi, Hoon-Chang (School of Civil and Environmental Engineering, Yeungnam University)
Choi, Jeong-Dong (School of Civil and Environmental Engineering, Yeungnam University)
Jung, Gyung-Yeung (Korea National Housing Corporation)
Jun, Seok-Ju (Korea National Housing Corporation)
Kwon, Soo-Yul (Department of Environmental Health, Korea National Open University)
Ahn, Young-Ho (School of Civil and Environmental Engineering, Yeungnam University)
Publication Information
Journal of Korean Society of Environmental Engineers / v.27, no.1, 2005 , pp. 93-100 More about this Journal
Abstract
Comparative thickening and dewatering characteristics of municipal wastewater sludge were investigated in terms of separated and combined treatment of primary and secondary BNR sludge. Also, various conditioning methods such as cation polymer addition, steam and ultrasonication treatment were examined to improve dewaterability of sludge. The dewaterability was measured by using specific resistant test, wedge zone simulator and centrifuge. The result of the sludge thickening test revealed that separated thickening was better in terms of solids recovery and supernatant quality. Particularly, the thickening of primary sludge with high solids (about 3.5% TS) showed very poor solid separation. The addition of cation polymer showed better conditioning characteristic for dewatering and the optimal polymer dosage was 0.26% for primary sludge, 0.43% for secondary sludge and 0.38% for combined sludge. Contrary to the result of the thickening, the dewatering test revealed that dewatering of the combined sludge is better than that of separated sludge, representing better solids separation and filtrate quality. The polymer addition was essential to improve dewaterability in filter (belt) press type dewatering but it was inefficient for the dewatering of secondary sludge only. The centrifuge type dewatering showed better performance and the dewaterability was slightly improved when the polymer was added. Based on the results of this research a sustainable sludge treatment process, particularly in terms of the recycle water quality and solids recovery, was proposed.
Keywords
Conditioning; Dewatering; Municipal Sludge; Specific Resistant Coefficient; Thickness; Wedge Zone Simulator (WZS);
Citations & Related Records
연도 인용수 순위
  • Reference
1 환경부, 하수슬러지 처리의 문제점 및 추진대책(직매립 금지 대응관련)(2003)
2 WEF, ASCE, Design of Municipal Wastewater Treatment Plants (MOP 8), 4th eds.(1998)
3 Ahn, Y. H. and Choi, H. C, Municipal sludge management and disposal in South Korea: status and a new sustainable approach, Water Sci. Technol., 50(9), 245-253(2004)   PUBMED
4 APHA, WEF and ASCE, Standard Methods for the Examination of Water and Wastewater, 20th Eds. Washington DC. USA(1998)
5 최의소, 상하수도 공학, 청문각(2003)
6 USEPA, Design Manual of Dewatering Municipal Wastewater Sludge, EPA/625/1-87/014, U.S.A.(1987)
7 최의소, 안영호, 도시하수슬러지의 농축특성에 관한 연구, 한국상하수도학회지, 1, 9-16(1991)
8 Lee, J. E., Kim, M. J., Lee, J. K., Development of electrodewatering filter press, Proc. IWA 3rd World Water Congress 2002, Melbourne, Australia, e21155a(2002)
9 Vesilind, P. A., Treatment and Disposal of Wastewater Sludge, rev. eds. Ann Arbor Science(1979)
10 Gopalakrishnan, S., Mujumdar, A. S., Weber, M. E., Electrokinetically enhanced vacuum dewatering of mineral slurries, Filtration & Technology, Nov/Dec, 929 (1996)
11 환경부, '03 하수종말처리시설 운영관리실태 분석(2004)
12 Nielson, B., Sludge dewatering methods and economy, Proc. of Sludge Use and Disposal (Sludge 2000), Robinson College, Cambridge(1992)
13 Barnard, J. L., Design of Prefermentation Processes. In Design and Retrofit of Wastewater Treatment Plants for Biological Nutrient Removal, C. W. Randall, J. L. Barnard, H. D. Stensel (Eds), Water Quality Management Library, 5, 85(1992)
14 이정언, 하수슬러지의 탈수율 향상을 위한 열 탈수 연구, 대한환경공학회지, 26(5), 601-609(2004)
15 한국수도협회, 환경부 제정 하수도 시설기준(1997)
16 Peuker, U., Scale-up of steam pressure filtration, Chem. Eng. Technol., 38, 611-619(1999)
17 환경부, 하수슬러지 처리 종합계획(2002)