Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Economic Assesment of Phosphorus Control System for Reject Water using a Integral Type Slow Mixing/Sedimentation Tank and Fiber Filter

일체형 완속교반침전조와 섬유여과기를 이용한 반류수 인 제어시스템의 경제성 연구

  • Received : 2017.06.19
  • Accepted : 2017.07.18
  • Published : 2017.12.01
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Abstract

As a method to reduce the total phosphorus in sewage treatment plant, we applied the integral type slow mixing/sedimentation fiber filtration system to compare the control methods for the sewage effluent and the reject water. It was analyzed that about 92.4 kg T-P/day should be removed in order to satisfy the final concentration of phosphorus of 0.2 mg T-P/L, which is reinforced effluent standard. Therefore the total phosphorus removal efficiency should be 96% for sewage effluent and 69.2% for reject water (dehydrated filtrate) respectively. The system operation cost to achieve the target of total phosphorus removal efficiency was assessed. It has been found that the treatment cost of the reject water containing high concentration of phosphorus with a low flow rate is reduced to about 1/2.4 of the coagulant cost and about 1/120 of the electricity cost, compared to that of the sewage effluent treatment. Also the economics of the integral type slow mixing/sedimentation fiber filtration system and the general coagulation and sedimentation system were compared. It was evaluated that the development system was more economical because the installation area of the integral type slow mixing/sedimentation fiber filtration system was about 1/7 smaller than that of the general coagulation and sedimentation system, and the annual operation cost including the required amount of coagulant and electricity cost of the development system was lowered about 1/1.7 than that of the general system.

하수처리장에서의 총 인 저감을 위한 방안으로 완속교반/침전 섬유여과시스템을 적용하여 하수 방류수와 반류수를 제어하는 방법에 대해 비교 검토하였다. 물질수지를 통해 인의 최종 농도를 강화된 기준치인 0.2 mg/L로 낮추기 위해서는 약 92.4 kg T-P/day를 제거해야 되는 것으로 분석되었으며, 이를 위한 총 인 제거효율은 하수 방류수는 96%, 반류수(탈수여액)은 69.2% 이상이 되어야 한다. 총 인 제거 목표치를 달성하기 위한 시스템 운영비용을 검토하였으며, 하수방류수를 처리하는 것보다 유량은 적으나 고농도의 인을 함유한 반류수를 처리하는 것이 약품비용은 약 1/2.4, 전력비용은 약 1/120 정도로 절감되는 것으로 나타났다. 한편 반류수 처리를 위해 개발시스템인 완속교반/침전 섬유여과시스템과 일반적인 응집침전시스템을 적용하는 경우에 대한 경제성을 검토하였으며, 완속교반/침전 섬유여과시스템이 일반적인 응집침전시스템에 비해 설치면적이 약 1/7로 작고 약품소요량 및 전력비를 포함한 연간운전비용은 약 1/1.7 소요되어 개발시스템이 보다 경제성이 있는 것으로 평가되었다.

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References

  1. Ministry of Environment, Korea, Guidelines for TMDL management (2004).
  2. Ministry of Environment, Korea, SEWERAGE ACT and ENFORCEMENT DECREE OF THE WATER QUALITY AND AQUATIC ECOSYSTEM CONSERVATION ACT (2010).
  3. Han River Water Management Committee, "Feasibility Study on the Application of Physicochemical Process for Phosphorous Removal in Environmental Facilities Located in Upper of the Watershed Lake," National Institute of Environmental Research, Han River Environment Research Center(2008).
  4. Ministry of Environment, Korea, "Utilization of Low Concentration Wastewater Treatment System by New Material Separation Membrane and Catalyst Ozone Process," 3-4, 95-101(2005).
  5. US. EPA REGION 10, April, Advanced treatment to achieve concentration of phosphorus(2007).
  6. Rittmann, B. E and McCarty, P. L., Environmental Biotechnology, McGraw Hill Korea, 579-590(2002).
  7. Neethling, J. B., Stensel, H. D., Sandino, J., Tsuchihashi, R., Clark, D. and Pramanik, A., "Achieving Low Effluent Total Phosphorus Concentration," Proceedings of the Water Environment Federation, WEFTEC 2013, 423-438(2013).
  8. Jeyanayagam, S., "True Confessions of the Biological Nutrient Removal Process," Florida Water Resources Journal: January (2005).
  9. John Bratby, "Coagulation and Flocculation in Waterand Wastewater Treatment," 2nd. Ed., IWA Publishing, London-Seattle, 119-149(2006).
  10. Hwang, E. J. and Cheon, H. C., "High-Rate Phosphorous Removal by PAC(Poly Aluminum Chloride) Coagulation of $A_{2}O$ Effluent," Korean Journal of KSEE, 31(8), 673-678(2009).
  11. Jang, J. G., Lee, S. H., Park, J. T., Jo, M. C., Kim, M. R. and Kim, J. S., "Development of Pilot Plant Slow Mixing/Sedimentation Net3FM System for Reject Water Treatment from the Sidestream of Wastewater Treatment Plant," KSWST Journal of Water Treatment, 22(2), 89-97(2014).
  12. Kim, M. H., Kim, M. R., Cheon, Y. J., Kim, G. H., Kim, J. S. and Jang, J. G, "Development of Treatment System for Sewage and Wastewater with High Concentration of Phosphorus and SS," Proceedings of the Kor. Environ. Sci. Soc. Conf., October, Daegu(2016).
  13. Park, K. Y., Lee, K. and Kim, J., "Manufacture of PAC(Polyaluminum Chloride) by Partial Decomposition of Aluminum Chloride Hexahydrate," J. of the Korean Institute of Chemical Engineers, 32(5), 742-746(1994).