Performance of anaerobic digestion (AD) of Palm Oil Mill Effluent (POME) with nitrogen-rich organic waste such as Waste Activated Sludge (WAS) was investigated in the batch experiment and continuous operation. In batch experiments, it was shown that the AD of POME needs sufficient alkalinity to maintain the stable pH. The alkalinity can be provided from inorganic chemical such as sodium bicarbonate as well as nitrogen-rich organic waste such as WAS. WAS was preferable than sodium bicarbonate for alkalinity source due to the synergistic and complementary effect of WAS with POME. The high content of total ammonia nitrogen in WAS made it possible to maintain stable pH and to enhance the performance of AD of POME. The methane yield in the mixture of POME and WAS were 22% and 81% higher than POME or WAS alone respectively. The methane production rate was 2 folds of WAS and 0.7 folds of POME. It also found that there was almost no lag period in the AD of POME and WAS. Thus, the mixing ratio of POME and WAS 40:60 which was in equivalent to COD/N ratio of 22 was necessary for the optimum methane production on the AD of POME and WAS. In the continuous operation, it was also shown that AD of POME and WAS with COD/N ratio of 22 was successfully operated with the methane yield improved up to 117% in the OLR of 1.5 g COD/L/d compared to WAS alone.
본 연구에서는 폐기물 활성화 슬러지(WAS)와 같이 고 질소 함유 유기성폐기물을 이용한 팜오일폐기물(POME)의 혐기성소화 성능을 배치실험과 연속운전실험을 통해 조사하였다.
배치실험의 경우, POME의 혐기성소화는 안정적인 pH를 유지하기 위해 충분한 알칼리 용액이 필요하였다
고 질소 함유 유기성폐기물은 Na2CO3과 같은 무기 화합물보다 알칼리도 조절에 더 좋았다.
WAS 내 고 농도의 총 암모니아성 질소는 pH의 안정적 유지와 POME의 AD의 성능을 향상시켰다.
POME와 WAS를 혼합하는 경우가 POME 또는 WAS만 사용한 경우보다 메탄 전환율은 22%, 생산량은 81% 훨씬 더 높았습니다.
또한 메탄 생산에 있어서 지연 기간이 거의 없었다.
POME의 혐기성소화 공정의 최적 조건 탐색을 위해서 조사한 POME와 WAS의 최적 혼합비율은 40:60으로 나타났으며, 이 때 COD/N의 비율은 22이었다.
연속운전의 경우, POME과 WAS가 40:60 비율과 OLR 1.5g COD/L/d의 조건에서 WAS와 비교 시 메탄 산출량이 117% 증가하여 성공적으로 운전이 이루어졌다.
