Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Simultaneous Treatment of Sewage Sludge and Food Wastewater Using Combined Digestion Process

혼합 소화공정을 통한 하수 슬러지와 음폐수 병합 처리

  • Ha, Jeong Hyub (Department of Integrated Environmental Systems, Pyeongtaek University) ;
  • Park, Jong Moon (Department of Chemical Engineering, Pohang University of Science and Technology)
  • 하정협 (평택대학교 환경융합시스템학과) ;
  • 박종문 (포스텍 화학공학과)
  • Received : 2017.08.24
  • Accepted : 2017.09.04
  • Published : 2017.10.10
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Abstract

In this study, in order to find the feasibility of thermophilic biological pre-treatment for the co-digestion of food wastewater and sewage sludge, digestion efficiency of the combined thermophilic aerobic and mesophilic anaerobic process and its effect on methane production were investigated. Also, a lab-scale co-digestion process was operated to observe parameter changes according to the increase of organic loading rates using different dilution ratios of distilled water and food wastewater (1/3 [Run I], 2/3 [Run II] in addition to using the raw food wastewater [Run III]). The results indicated that co-digestion process maintained quite stable and constant pH during entire experiments. With regard to VS removal, the higher removal was observed in the combined process and the removal efficiency was 52.24% (Run I), 66.59% (Run II) and 72.53 (Run III), respectively. In addition, the combined process showed about an 1.6-fold improved methane production rate and significantly higher methane yield than that of using single anaerobic digestion process.

본 연구에서는 하수 슬러지 및 음폐수의 효율적인 병합처리를 위해 고온호기 전처리의 적용가능성을 알아보고자 고온호기-중온혐기 연계공정의 소화효율과 메탄가스 생성량에 미치는 영향을 비교 검증하였다. 또한, 유기물 부하량 증가에 따른 공정 내 변화 양상을 관찰하기 위해 실험실 규모의 고온호기-중온혐기 소화장치를 제작하여 음폐수를 증류수로 희석하는 비율을 1/3 (Run I), 2/3 (Run II) 및 원액(Run III)으로 줄여가며 혐기소화 공정 내 변화 양상을 관찰하였다. 실험 결과 별도의 pH 조절 없이 고온호기-중온혐기 연계공정 소화조 내에서 pH가 7~8으로 안정하게 유지됨을 알 수 있었다. Volatile solid (VS)는 순응 기간 후 고온호기-중온혐기 연계공정에서 52.24% (Run I), 66.59% (Run II) 및 72.53% (Run III)의 제거효율을 보이며, 중온혐기 소화조(R3)에 비교하여 높은 VS 제거율을 보였다. 또한, 고온호기-중온혐기(R1-R2) 연계공정에서 약 1.6배 향상된 메탄 생성률이 관찰되었으며, 메탄수율의 경우에도 고온호기-중온혐기(R1-R2) 연계공정에서 현저하게 높은 값을 유지하였다.

Keywords

References

  1. M. Kim, Y. H. Ahn, and R. E. Speece, Comparative process stability and efficiency of anaerobic digestion; mesophilic vs. thermophilic, Water Res., 36, 4369-4385 (2002). https://doi.org/10.1016/S0043-1354(02)00147-1
  2. H. M. Jang, J. H. Ha, M. S. Kim, J. O. Kim, Y. M. Kim, and J. M. Park, Effect of increased load of high-strength food wastewater in thermophilic and mesophilic anaerobic co-digestion of waste activated sludge on bacterial community structure, Water Res., 99, 140-148 (2016). https://doi.org/10.1016/j.watres.2016.04.051
  3. Korea Ministry of Environment, Bioenergy facilities and status using organic wastes, Seoul, South Korea (2013).
  4. Korea Ministry of Environment, Treatment plan and bioenergy production for organic wastes and food wastewater, Seoul, South Korea (2012).
  5. H. M. Jang, S. S. Choi, and J. H. Ha, Comparison of single-stage thermophilic and mesophilic anaerobic sewage sludge digestion, Appl. Chem. Eng., 27, 532-536 (2016). https://doi.org/10.14478/ace.2016.1084
  6. H. Y. Cho, S. K. Park, J. H. Ha, and J. M. Park, An innovative sewage sludge reduction by using combined mesophilic anaerobic and thermophilic aerobic process with thermal-alkaline pretreatment, J. Environ. Manag., 129, 274-282 (2013). https://doi.org/10.1016/j.jenvman.2013.07.009
  7. H. M. Jang, S. S. Choi, J. H. Ha, and J. M. Park, Influence of food wastewater loading rate on the reactor performance and stability in the thermophilic aerobic process, Appl. Chem. Eng., 24, 279-284 (2013).
  8. H. M. Jang, S. K. Park, J. H. Ha, and J. M. Park, Microbial community structure in thermophilic aerobic digestion used as a sludge pretrement for mesophilic anaerobic digestion and enhancement of methane production, Bioresour. Technol., 145, 80-89 (2013). https://doi.org/10.1016/j.biortech.2013.01.094
  9. APHA, Standard Methods for the Examination of water and Wastewater, 20th ed., American Public Health Association (APHA), Washington DC, USA (1998).
  10. J. T. Novac, S. Banjade, and S. N. Murthy, Combined anaerobic and aerobic digestion for increased soilds reduction and nitrogen removal, Water Res., 45, 618-624 (2011). https://doi.org/10.1016/j.watres.2010.08.014
  11. H. M. Jang, J. W. Lee, J. H. Ha, and J. M. Park, Effects of organic loading rates on the reactor performance and microbial community changes in the thermophilic aerobic process treating high-strength food wastewater, Bioresour. Technol., 148, 261-269 (2013). https://doi.org/10.1016/j.biortech.2013.08.090
  12. G. Parkin and W. F. Owen, Fundamentals of anaerobic digestion of wastewater sludge, J. Environ. Eng., 112, 867-920 (1986). https://doi.org/10.1061/(ASCE)0733-9372(1986)112:5(867)
  13. S. Hasegawa, N. Shiota, K. Katsura, and K. Akashi, Solubilization of organic sludge by thermophilic aerobic bacteria as a pretreatment for anaerobic digestion. Water Sci. Technol., 41, 163-169 (2000).
  14. P. Juteau, D. Tremblay, C. B. Ould-Moulaye, J. G. Bisaillon, and R. Beaudet, Swine waste treatment by self-heating aerobic thermophilic bioreactors, Water Res., 38, 539-546 (2004). https://doi.org/10.1016/j.watres.2003.11.001