• Environmental Engineering Research
• /
• 제23권1호
• /
• pp.46-53
• /
• 2018

This study explores the environmentally innovative and low-impact technology, a zero food waste system (ZFWS) that utilizes food waste and converts it into composts or biofuels and curtails carbon emissions. The ZFWS not just achieves food waste reductions but recycles food waste into fertilizer. Based on a fermentation-extinction technique using bio wood chips, the ZFWS was employed in a field experiment of the system installed in a large-scale apartment complex, and the performance of the system was examined. The on-site ZFWS consisted of three primary parts: 1) a food waste slot into which food waste was injected; 2) a fermentation-extinction reactor where food waste was mixed with bio wood chips made up of complex enzyme and aseptic wood chips; and 3) deodorization equipment in which an ultraviolet and ozone photolysis method was employed. The field experiment showed that food waste injected into the ZFWS was reduced by 94%. Overall microbial activity of the food waste in the fermentation-extinction reactor was measured using adenosine tri-phosphate (ATP), and the degradation rate of organic compounds, referred to as volatile solids, increased with ATP concentration. The by-products generated from ZFWS comply with the national standard for organic fertilizer.

• Asian-Australasian Journal of Animal Sciences
• /
• 제12권4호
• /
• pp.604-606
• /
• 1999

Solid animal wastes in Japan are treated mainly by composting. The composting process under controlled conditions is able to convert the wastes into high-quality organic fertilizer. Various types of composting facilities with/without forced aeration and turning device are available. Characterization of the maturing process during composting was studied, to improve the quality of compost and to make the degree of maturity. Recycling of animal wastes as compost without any environmental pollution will be closely related to the development of sustainable agriculture with organic fertilizer in Japan.

• 한국환경보건학회지
• /
• 제27권1호
• /
• pp.14-19
• /
• 2001

The physical and chemical transformation and reduction degree of food waste were investigated in a food waste reduction machine using thermophilic bacteria. The first operation of the reduction machine for grain, vegetables, fishes and flesh wastes proceeded during three weeks. The first and second reduction percentages of the wastes were 98.3% and 93.2%, respectively. The residue of food waste was composed of fruits, fish, and vegetables. The temperature distribution of the reduction machine ranged between 30 and 6$0^{\circ}C$ appropriate for growth of thermophilic bacteria. At initial stage the pH in the reduction machine decreased with organic acids produced, but increased as the organic acids decomposed by different thermophilic bacteria. In the reduction machine, the moisture content of the food waste was reduced from 80-90% to 10-20% after 24 hours, and the salinity of residue was 0.29% after the second operation. The degree of odor was most high between 2 and 4 hours.

• 유기물자원화
• /
• 제16권2호
• /
• pp.29-37
• /
• 2008

본 연구에서는 하수슬러지, 음식물쓰레기, 분뇨계 폐기물과 같은 고농도 유기성 폐기물의 고온 메탄 발효에 대하여 공정, 응용 현황 및 장 단점의 여러가지 측면에서 고찰이 이루어졌다. 고온 메탄 발효의 장점은 반응속도가 빠르고, 높은 부하량에서 처리가능하고, 병원성 미생물의 사멸율이 높고, 소화오니는 보다 위생적이었다. 그러나, 단점으로서는 발효시설을 가열하는데 많은 에너지를 요구하고, 저농도 유기성 폐기물에서는 잉여에너지를 얻을 수 없고, 발효처리 후 상등수 수질이 떨어지게 되며, 그 결과 배수처리에 부담이 된다. 특히, 고농도 메탄 발효의 경우 영양염 부족이나 ${NH_4}^+-N$에 의한 방해가 일어나기 쉬우므로, 이에 대하여 적절한 대안이 요구된다. 일반적으로 고온 메탄 발효는 고농도의 우분뇨와 음식물 유기성 폐기물의 좋은 처리 수단으로 고려되었다. 반대로, 폐기물 그 자체의 농도가 낮을 경우와 ${NH_4}^+-N$이 3.000mg/L 이상 높게 되는 조건에서 고온 메탄 발효는 바람직하지 않는 결과를 나타내게 된다.

• 한국유기농업학회지
• /
• 제17권1호
• /
• pp.55-62
• /
• 2009

저면도포 무처리구에서 유기상토에 느타리버섯 폐배지로 생산한 분립 4-6%의 첨가비율에서 벼의 유식물체의 생육이 가장 좋았다. 저면도포 처리구에서는 대조구(유기상토 100%)에서 벼의 유식물체의 생육이 가장 좋았는데, 이는 신장된 뿌리가 토양표면에 시용된 분립으로부터 생육에 필요한 양분을 흡수하였기 때문으로 추정된다 따라서 장기간 육묘할 경우에는 유기상토에 분립을 혼합하지 않고 토양표면에 분립 100%를 시용하는 저면도포 방법이 효율적이라고 생각된다. 느타리버섯 폐배지로 생산한 분립은 중금속 함량이 낮아서 안전성이 높고. 양분공급능력이 높은 유기상토재로서 이웅 가능성이 높다고 판단된다. 유기상토의 양분공급능력을 높여 유식물체의 생육을 촉진하기 위해서는 분립과 같은 상토재의 첨가를 통하여 질소함량은 높이고, 탄질율은 낮추는 것이 필요하다고 판단된다.

• 대한조선학회 특별논문집
• /
• 대한조선학회 2013년도 특별논문집
• /
• pp.103-109
• /
• 2013

The Present work focuses on application of Organic Rankine Cycle - Waste heat Recovery System (ORC-WHRS) for marine diesel engine. ORC and its combined cycle with the engine were simulated and its performance was estimated theoretically under the various engine operation conditions and cooling water conditions. The working fluid, R245fa, was selected for the consideration of the heat source temperature, system efficiency and safety issues. According to the thermodynamic analysis, ~13.1% of system efficiency of the cycle was performed and it is about 4% of the mechanical power output of the considering Marine Diesel Engine. Also, addition of evaporator and pre-heater were studied to maximize output power of Organic Rankine Cycle as a waste heat recovery system of the marine diesel engine.

• 환경위생공학
• /
• 제16권1호
• /
• pp.108-116
• /
• 2001

It is difficult to task to achieve high biological nutrient removal from municipal wastewater because of low organic content. Volatile fatty acids(VFAs) produced from acid fermentation of food wastes can be utilized as external carbon sources for the biological nutrient process. Significant reduction and stabilization of the food wastes can also be obtained from the acid fermentation. The objective of this study is to evaluate characteristics of acid fermentation of the food wastes. Results obtained from the batch experiment of various organic wastes showed that the food wastes had high potential to be used as an external carbon source because of the largest production of the VFAs with low nitrogen and phosphorus content. The fish waste was found to be the next possible organic waste, while the others such as radish cabbage and molasses waste showed high VFAs consumption potential as a results of high nitrogen and phosphorus content. alkaline hydrolysis of the food waste was carried out using NaOH prior to the acid fermentation. As the alkali addition increased, solubilization of the organics as well as TSS reduction increased. However, fraction of soluble COD to total COD became stable after a sharp increase. Alkali addition greater than 0.5g NaOH per g TS resulted in significant increase in pH.

• 한국유기농업학회지
• /
• 제5권1호
• /
• pp.125-135
• /
• 1996

A study was made to investigate the possibility of treating various organic waste of cattle manure, swine manure, goat manure, apple pomace, chinese medicine residue and coffee less by feeding these to earthworms and then by studying the growth and reproductive efficiency of earthworms, and the chemical composition of worm cast and its production. The results are summarized as follows. 1. When the feed for earthworms were in good condition which were cattle manure, swine manure and apple pomace, the reproductive efficiency of earthworms was improved however in worse condition the feed of which were goat manure and chinese medicine residue, the increasing rate(IR) became faster. 2. Despite the high content of organic matter(OM) in coffee lees, the earthworms fed coffee lees showed significantly lower reproductive efficiency and increasing rate(IR) than those fed other organic waste due mainly to its lower pH and lower total nitrogen(TN) content. Therefore, when coffee lees is considered to be fed to earthworms, it is believed necessary to be mixed with addiveves or other organic waste in order to improve the feed condition. 3. pH in swine manure, goat manure, apple pomace, chinese medicine residue and coffee lees became neutralized by being fed by earthworms. 4. Available P2O5 and exchangeable cation(EC) of earthworm cast were a little increased compared to those of feed. The contents of Mn, Fe and Cu in earthworm cast were a little decreased to compared to those of feed. 5. The contents of Mn, Fe and Cu in earthworm cast were a little a decreased to compared to those of feed. 6. Mean fresh weight of earthworm at final time(FW2) was negatively correlated with number of young worms(NY)(P<0.01), but positively with increasing rate(IR) (P<0.001) and C/N ratio(P<0.05) respectively. Number of cocoons (NC) and fresh weight of cocoons(WC) were positively(P<0.01) correlated with fresh weight of young worms (WY) and digested matter(DI) but negatively(P<0.001) correlated with residual matter(WY) and digested matter(DI) but negatively(P<0.001) correlated with residual matter(RW). Number of young worms(NY) and fresh weigh of young worms(WY) were negatively(P<0.001) correlated with increasing rate(IR), however increasing rate(IR) of earthworm was positively(P<0.05) correlatedd with C/N ratio.

• 유기물자원화
• /
• 제19권1호
• /
• pp.102-108
• /
• 2011

혐기성 회분식 반응조를 이용하여 다양한 유기성 폐기물의 에너지화 가능성을 평가하기 위하여 수소발생 특성을 평가하였다. 본 연구에서 채소류는 파, 과일류는 사과, 곡류는 쌀밥 그리고 육류로는 돼지고기를 사용하였다. 파, 사과, 쌀밥 및 돼지고기의 최종 수소 수율은 각각 0.46, 0.47, 0.62 및 $0.05mol\;H_2/mol\;hexose$로 나타났다. 수소 발생율은 파, 사과, 쌀밥 및 돼지고기에서 각각 0.013, 0.021, 0.014 및 $0.005mol\;H_2/mol\;hexose/h$로 평가되었다. 따라서 돼지고기를 제외한 음식폐기물의 혐기성 수소 발효는 재생에너지 생산뿐만 아니라, 유기물의 제거에 효과적인 것으로 나타났다. 휘발성 지방산은 수리학적 체류시간이 증가함에 따라 높게 발생되는 것으로 나타났다. 수소 발효시 산발효 효율은 쌀밥이 75.8%로 가장 높게 나타났으며, 돼지고기는 35.2%로 가장 낮게 나타났다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
• /
• pp.676-681
• /
• 1999

The organic matter flow in rural watershed in Chongwon-gun , Chungbuk, was evaluated, The study watershed is about 67$\textrm{km}^2$ in area and its population was 7,000 in 1996. The amount of inflow in the study area exceeds the amount of outflow by 534kg/ha , and the livestock feed account for 90 percent of the amount of inflow. The loading of organic matter by livestock waste amounts to 51 percent of total loading to agricultural land and the enviornment. The increase in recycling of livestock waste is essential for the management of orgainc matter in the rural watershed.