DOI QR코드

DOI QR Code

Development of an UV Distribution Model for the Design of a Submerged UV Disinfection Reactor and Its Application

침지형 자외선 살균조 설계를 위한 자외선 분포 모델의 개발 및 적용

  • 박창연 (조선대학교 토목공학과) ;
  • 김성홍 (조선대학교 토목공학과) ;
  • 최영균 (충남대학교 환경공학과)
  • Received : 2021.04.05
  • Accepted : 2021.05.17
  • Published : 2021.10.01

Abstract

A 3D model was developed to calculate the UV intensity of a submerged-type UV disinfection reactor. Numerical experiments were conducted by inputting the design factors of an open channel-type disinfection reactor and a pipe-type disinfection reactor that were installed in an actual sewage treatment plant. The following data were obtained: The average UV intensity of the installed open channel-type reactor and pipe-type reactor was 7.87 mW/cm2 and 13.09 mW/cm2, respectively; the UV dose reflecting the UV irradiation time and taking into account attenuation effects such as mixing imbalance, lamp aging, temperature, and fouling, was expected to be 21.1 mJ/cm2 and 24.8 mJ/cm2, respectively, and these values are 5 % and 24 % higher than the target UV dose of 20 mJ/cm2, respectively. By using the UV3D model, the optimal lamp position, which maximizes the average UV intensity without changing the size of the disinfection reactor or lamp output power, can be found. In this case, by only adjusting the lamp position, the average UV intensity can be increased by 0.9 % for the open channel-type and 0.5 % for the pipe-type, respectively. A better average UV intensity can be obtained by model simulation. By adjusting the horizontal and vertical ratio of the open channel-type reactor and by moving the lamp position, the average UV intensity can be increased by 7.4 % more than the present case.

침지형 자외선 살균조의 자외선 강도를 계산하기 위한 3차원 모델을 개발하였으며, 실제 하수처리장에 설치되어있는 개수로형 살균조와 관로형 살균조에 각각 적용하여 수치실험을 실시하였다. 모델링을 통해 계산한 살균조의 평균 자외선 강도는 각각 7.87 mW/cm2와 13.09 mW/cm2로 계산되었다. 자외선 조사 시간을 반영하고, 혼합 불균형, 램프 노화, 온도 및 파울링에 의한 감쇄효과를 고려한 자외선 조사량은 각각 21.1 mJ/cm2, 24.8 mJ/cm2로 예측되었는데 이 값은 목표 자외선 조사량인 20 mJ/cm2보다 각각 5 %, 24 % 높은 것으로 예측되었다. 개발한 UV3D 모델을 사용하면 살균조의 조사 시간이나 램프의 출력을 높이지 않고도 수치실험을 통해 평균 자외선 강도가 가장 큰 최적의 램프 위치를 찾을 수 있다. 램프 위치 조정만으로 본 연구에서 적용한 개수로형 살균조와 관로형 살균조의 자외선 조사량은 각각 0.9 %, 0.5 % 향상시킬 수 있다. 개수로형 살균조의 경우 살균조의 체적은 그대로 유지하면서 가로와 세로의 비율을 조정하고, 램프의 위치를 바꾸면 평균 자외선 강도는 현재보다 7.4 % 더 증가한다.

Keywords

Acknowledgement

본 연구는 2019년도 조선대학교 교내연구비 지원에 의해 이루어졌습니다.

References

  1. Andreadakis, A., Mamais, D., Christoulas, D. and Kabylafka, S. (1999). "Ultraviolet disinfection of secondary and tertiary effluent in the mediterranean region." Water Science and Technology, Vol. 40, No. 4-5, pp. 253-260. https://doi.org/10.1016/S0273-1223(99)00506-5
  2. Bolton, J. R. (2000). "Calculation of ultraviolet fluence rate distributions in an annular reactor: Significance of refraction and reflection." Water Research, Vol. 34, No. 13, pp. 3315-3324. https://doi.org/10.1016/S0043-1354(00)00087-7
  3. Bolyard, S. C., Motlagn, A. M., Lozinski, D. and Reinhart, D. R. (2019). "Impact of organic matter from leachate discharged to wastewater treatment plants on effluent quality and UV disinfection." Waste Management, Vol. 88, pp. 257-267. https://doi.org/10.1016/j.wasman.2019.03.036
  4. Chiu, K., Lyn, D. A., Savoye, P. and Blatchley III, E. R. (1999). "Intergrated UV disinfection model based on particle tracking." Journal of Environmental Engineering, Vol. 125, No. 1, pp. 7-16. https://doi.org/10.1061/(ASCE)0733-9372(1999)125:1(7)
  5. Environmental Protection Agency (EPA) (1999). Wastewater technology fact sheet ultraviolet disinfection, EPA, pp. 3.
  6. Gilboa, Y. and Friedler, E. (2008). "UV disinfection of RBC-treated light greywater effluent: Kinetics, survival and regrowth of selected microorganisms." Water Research, Vol. 42, No. 4-5, pp. 1043-1050. https://doi.org/10.1016/j.watres.2007.09.027
  7. Hallmich, C. and Gehr, R. (2010). "Effect of pre- and post-UV disinfection conditions on photoreactivation of fecal coliforms in wastewater effluents." Water Research, Vol. 44, No. 9, pp. 2885-2893. https://doi.org/10.1016/j.watres.2010.02.003
  8. Jeon, H. B., Yun, J. W. and Kim, S. H. (2012). "Optical characteristics of the UV intensity distribution in a non-contact type UV photoreactor." Journal of the Korean Society of Water and Wastewater, Vol. 26, No. 2, pp. 257-264 (in Korean). https://doi.org/10.11001/jksww.2012.26.2.257
  9. Kim, S. H. (2008). "A Study on the ultraviolet disinfection in a water treatment plant." International Journal of Advanced Engineering and Technology, Vol. 1, No. 2, pp. 1-6 (in Korean).
  10. Kim, S. H., Kim, K. M., Kim, G. I. and Choi, J. W. (2016). "Disinfection of E. coli from wastewater using a non-contact type UV photoreactor and log inactivation index." Journal of the Korean Society of Water and Wastewater, Vol. 30, No. 2, pp. 139-145 (in Korean). https://doi.org/10.11001/jksww.2016.30.2.139
  11. Lee, W. H., Choi, Y. G. and Kim, S. H. (2014). "Calibration of an ultraviolet distribution model by precise measurement of underwater ultraviolet intensities." Korean Journal of Chemical Engineering, Vol. 31, No. 10, pp. 1780-1785. https://doi.org/10.1007/s11814-014-0134-z
  12. Liu, D., Ducoste, J., Jin, S. and Linden, K. (2004). "Evaluation of alternative fluence rate distribution models." Journal of Water Supply: Research and Technology, Vol. 53, No. 6, pp. 391-408. https://doi.org/10.2166/aqua.2004.0031
  13. Ministry of Environment (MOE) (2011). Standard of sewage facilities, Ministry of Environment of Korea, pp. 567 (in Korean).
  14. Ministry of Environment (MOE) (2019). Statistics of sewerage, Ministry of Environment of Korea (in Korean). Available at: https://www.hasudoinfo.or.kr/ (Accessed: March 31, 2021).
  15. National Water Research Institute (NWRI) (2012). Guidelines for drinking water and water reuse - Third edition, National Water Research Institute, pp. 23.