이 연구에서는 TEC-BNR공법을 사용하는 하수처리장에서 강수발생시와 같은 저농도 유입수에, 하수처리장의 생슬러지, 분뇨처리수, 그리고 음식물 쓰레기 처리액을 산발효하여 생성된 유기산을 외부탄소원으로 투입하였을 때, 비탈질율과 인방출율의 변화를 정량적으로 측정하였다. 이 연구에 의하면 산발효액 투입하였을 때 평균 비탈질율은 산발효액의 투입율이 0.5%일 때 215%, 투입율이 1%일 때는 169% 증가하였고, 평균 인방출양은 산발효액의 투입율이 0.5%일 때 46%, 투입율이 1%일 때는 63%로 증가하는 것으로 밝혀졌다. 또한 이 연구의 결과를 통하여 탈질에 이용된 VFA양(12.6∼32.3 mgVFA/mgNO₃-N)과 인방출에 이용된 VFA양(1.7∼2.4 mgVFA/mgPO₄-P)도 계산할 수 있었다. 이 연구의 결과를 활용하면 하수처리장에서 저농도 유입수에 산발효액을 외부탄소원으로 사용할 경우, 탈질과 인 제거를 최적화하기 위한 산발효액(VFA)의 양을 정량화할 수 있을 것으로 생각된다.
The amount of waste water generated from the domestic sources is consistently increasing in proportion to economic growth, and the conventional activated sludge process is widely being used for general waste water treatment. But the ministry of environment becomes stringthent treatment standards of N and P (less than 20mg/L of N, 2mg/L of P) to prevent the eutrophication of lake water, and therefore highly advanced treatment technology is required not only in the existing treatment plants where the activated sludge process is being used, but also in newly constructed treatment plants for the treatment of N and P. This study is aimed at highly operating the engineering technology method was developed by domestic to eliminate N and P at the same time. Experiments were conducted in the treatment plant located in Yong In city. The bioreactor was started from the principal equipment for the elimination of N and P and the elimination of organic compounds. It consists of an internal recycle piping from the end of the aerobic tank to the anoxic tank and external recycle piping from the final settling basin to the denitrification tank. By experiment of 4 types separate inflow of waste water to the denitrification tank and the anaerobic tank, and changes in staying time at the anoxic tank and the aerobic tank, the elimination of organic compounds in each type and the relationship in the efficiency between the elimination of N and P were researched.
Caustic (NaOH) solution is used to remove H2S from hydrocarbon streams in petroleum refining industry, gradually being, so called, spent sulfidic caustic (SSC) which has high levels of H2S and alkalinity. Thus, SSC can be used as an electron donor and a buffering agent for autotrophic denitrification. As SSC, however, contains some non-biodegradable organics, air stripping was conducted to remove the non-biodegradable organics. As a result, over 93 % of the non-biodegradable organics was removed within 30 min of aeration. Then, Na2S2O3·5H2O, methanol and organic matters, which are produced from a biodiesel production plant, were added to reform the air-stripped SSC and their products being referred to new sulfidic caustics (NSCs)Ⅰ, Ⅱ and Ⅲ, respectively. Thereafter, to investigate the effect of these products on the removal of COD and TN, these products were injected to a biological nitrogen removal (BNR) process, resulting in additional 44 % TN removal without noticeable increase in the effluent COD level. Therefore, it can be said that the BNR process is a promising option to treat NSC as demonstrated in this study whose results can be useful for developing resource recovery technologies.