This study evaluated the odor mitigation effect of rice husk biochar addition to the bedded pack dairy barn floor using lab-scale reactors for five days. Rice husk biochar mixed with dairy manure and sawdust mixture at different ratios (5%-addition test unit: adding biochar by 5% of the total solid weight of the mixture, 10%-addition test unit: adding biochar by 10% of the total solid weight of the mixture). Cumulative NH3 and H2S emissions of 10%-addition test unit were reduced by 26% (p< 0.05) and 46% (p = 0.0655), respectively, compared with control. However, 5%-addition test unit did not show NH3 and H2S emission reduction. Further research is needed to determine the appropriate level of biochar addition between 5 and 10%, and to evaluate applicability in the field through economic analysis.
This study was conducted to find an efficient and economical mixing ratio of deodorant and a isolated microorganism to reduce ammonia in livestock manure compost. In this study, a simple experimental device that can compare the degree of odor reduction by connecting the vial containing the odor generating source and the gas detection tube and leaving it to stand was used. This test method cannot accurately measure ammonia concentration according to the characteristics of the detector tube, but it is an easy method to compare various experimental conditions. The microorganism isolated from pig manure, “Enterococcus casseliflavus” was found to have an effect on ammonia reduction. Surfactant (sodium dodecyl sulfate), mineral A, mineral B, sulfur, persimmon leaves, and glycerin used as a deodorant were mixed with E. casseliflavus NO-2-L to find the optimum mixing ratio. When 20% of deodorants and E. casseliflavus NO-2-L were added to the source of odor alone, the ammonia reduction efficiency of NO-2-L was the highest (66.7%) compared with other deodorants. When a mixture of microorganisms and deodorants were used, the ammonia reduction efficiency was the best when the mixing ratio of the deodorant was 20%. When mineral B and sulfur were added, the ammonia concentration reduction efficiency was the highest at 83.3%.
The raw drinking water quality is getting worse because of the winter drought and the conventional treatment system is'nt suitable to obtain the satisfied quality of water. So, the advanced water system, BAC(Biological Activated Carbon) process is said to be effective to remove dissolved organics and ammonia nitrogen. In our study, the BAC pilot plant using Nak-dong river water is tested in low temperature. Following results are found from the study. The ammonia nitrogen removal rate of BAC system using wood-based carbon (PICABIOL) was 99% in $6^{\circ}C$ temperature. Chlorine dosage in wood-based BAC effluent was reduced to 67% of that in sand filtered wate. It resulted from the removal of ammonia nitrogen. Also, THM formed by chlorine addition in wood-based BAC effluent was decreased to 65% of that in sand filtered water. In the case of dual-filter, the removal efficiency of ammonia nitrogen was increased 30% more than in conventional sand filter. According to this result, the ammonia nitrogen load to BAC system could be lessened by the use of dual-filter.
도시생활폐기물소각재(MSWI ash)을 매립하게 되면 장기적으로 중금속이 침출된다. 급속탄산화를 통하여 MSWI ash 내의 중금속을 탄산염 형태로 고정하여, 중장기적으로 침출을 방지할 수 있다. 본 연구에서는 급속 탄산화 방법을 통하여 소각재인 fly ash의 중금속 저감 및 이산화탄소 저감에 대해 수행하였다. NH4OH, NH4SCN, 및Ca(OH)2를 이용하여 test 하였으며, 소각재의 중금속을 탄산화 전, 후를 비교하여 중금속이 침출량을 비교 하였다. 추가적으로 이산화탄소가 fly ash에 포집된 이산화탄소 저감량을 나타내면서 이산화탄소 흡수제의 재사용 가능성을 확인하였다. 흡수제를 재생하는 과정에서 나온 CO32-이온에 의해 탄산화 된 금속염들의 성분 분석을 위해, XRD (X-ray diffraction analyzer(Ultima Ⅳ))를 사용하였다. 그리고 FE-SEM(Field emission scanning electron microscope, JEOL-7800)으로 filtering후 건조시킨 샘플과 fly ash의 표면구조를 촬영하고 비교하였다.
온실가스인 이산화탄소는 다른 온실가스에 비해 Global Warming Potential(GWP)가 가장 낮지만 배출량이 전체 온실가스 중 88 %의 비중을 차지하고 있다. 많은 국가에서 기후변화에 관심을 가지고 이산화탄소 저감에 대한 연구개발이 활발히 일어나고 있다. 본 연구에서는 암모늄 화합물을 이용하여 이산화탄소를 포집하고 산업폐기물의 금속이온을 이용하여 무기재료인 탄산칼슘을 생성하는 다양한 방법을 소개한다. 탄산칼슘 생성을 위해 칼슘이온이 포함된 탈황석고, 폐시멘트를 이용하였다. 결과에서 이산화탄소 포집 성능 및 최종생성물의 결정구조를 확인하였으며, 이산화탄소 loading 값 는 약 2.0의 값을 가진다. X-Ray Diffraction, Scanning Electron Microscope의 분석을 통하여 탄산칼슘이 생성되었음을 확인하였으며, 결정구조는 Vaterite가 생성됨을 확인할 수 있다. 효과적인 공정을 위하여, 생성물을 생성한 후 용액을 회수하여 재이용할 수 있어 연속적인 공정이 가능하다. 회수된 용액의 재이용의 가능성을 보기위하여 이산화탄소를 재흡수 시키면서 같은 공정을 2cycle씩 진행하여, 연속적인 공정의 잠재성을 확인하였다.