Odor emitted from food waste is commonly known as a severe problem, and needs to be controlled to minimize public complaints against food waste collection systems. In this study, ozone oxidation with manganese oxide catalyst, which is known to effectively treat odorous substances at room temperature, was applied to remove acetaldehyde and hydrogen sulfide, the model odorous compounds from food waste. In addition, the effect of relative humidity (RH) on the ozone/catalyst oxidation was tested at 40%, 60%, and 80%. When the catalyst was not applied, the removal of acetaldehyde was not observed with the ozone oxidation alone. In addition, hydrogen sulfide was slowly oxidized without a clear relationship under RH conditions. Meanwhile, the ozone oxidation rates for acetaldehyde and hydrogen sulfide substantially increased in the presence of the catalyst, but the removal efficiencies for both compounds decreased with increasing RH. Under the high RH conditions, active oxygen radicals, which were generated by ozone decomposition on the surface of the catalyst, were presumably absorbed and reacted with moisture, and the decomposition rate of the odorous compounds might be limited. Consequently, when the ozone oxidation device with a catalyst was applied to control odor from food waste, RH must be taken into account to determine the removal rates of target compounds. Moreover, its effect on the system performance must be carefully evaluated.

During the decay process of food waste, odor and leachate are generally produced because food is easily decomposed due to its high organic and moisture contents. In this study, various food waste samples, including samples artificially prepared and collected from actual waste containers, were tested to determine odor and leachate production as the samples were decomposed at a constant temperature of 35°C. In the air phase, total volatile organic compounds (TVOCs), acetaldehyde (AA), methyl mercaptan (MM), hydrogen sulfide (H2S), and dimethyl sulfide (DMS) were measured as a function of the decay period for four days. The results of the experiment showed that TVOC and AA were produced at higher concentrations in the actual food waste than in all artificial wastes. The AA concentration accounted for about 90% of the TVOC in all of the waste samples except for the food waste containing meat and fish only. The concentrations of volatile sulfur compounds (VSCs) were generally lower than 100 μg/kg, and the concentration of DMS was the highest among the VSCs. In the waste sample containing meat and fish only; however, the concentration of VSCs increased up to 1,700 μg/kg, and mostly consisted of MM and DMS. Complex odor concentrations were found to be the highest after a decay period of 12-48 hours. In addition, the complex odor was mostly related to VSCs with low odor thresholds rather than the TVOC. The pH values mostly decreased from 5 to 3.5 as the waste samples were in the decomposition periods, while the pH value increased to 6 in the food waste containing meat and fish only. Consequently, odor intensity and leachate production were the highest in the 12-48 hour range as the decomposition started, and thus an appropriate control strategy needs to be implemented based on the waste composition and the decay period.

This study was performed to measure the concentration of odorous compounds and dilution ratio values at each part of the anaerobic digester process with composting facilities using swine manure and food waste. Complex odors, ammonia, volatile fatty acids and sulfur compounds were measured at each part of the process. Complex odors measured during swine manure storage, food waste storage and in the digested liquid tank, were 35,312 Odor Unit(OU), 39,086 OU and 17,733 OU, respectively. The odor contribution index was calculated by the concentration of odorous compounds during each process divided by the threshold limit. As a result, the major odorous compound that appeared during swine manure storage, food waste storage and in the digested liquid tank was hydrogen sulfide. On the other hand, the major odorous compound in the other processes was ammonia. The overall average concentrations of ammonia were highest in the digested liquid tank(337 ppm) and the separated liquid tank(131 ppm). Wastewater treatment process(10.9 ppm) and deodorization process(11.6 ppm) revealed the lowest concentration of ammonia. The overall average concentration of total volatile fatty acids(TVFAs) was 102.8 ppb during food waste storage and among the TVFAs, the main element was propionic acid(66.1 ppb). Sulfur compounds were only detected during swine manure storage, food waste storage and in the digested liquid tank. The dominant sulfur compound was hydrogen sulfide during swine manure storage(96.3 ppm) and methyl mercaptan during food waste storage(17.7 ppm) and dimethyl sulfide during food waste storage(34.5 ppm).

In this study, we aim at the workplace which is report target about person who emits much food waste, apartment house and detached house. We respectively selected 3 places in this study. Density of average complex bad odor which is generated in storage container of food waste appears high in order of workplace(2,523.8 OU/m3), apartment house(2,135.7 OU/m3) and detached house(1,556.5 OU/m3). And then, it doesn’t seem like big difference. However, these appear degree of bad smell intensity which is more than 3. Meanwhile, bad smell intensity about 3 same occurrence sources which are classified (three places which are respectively workplace, apartment house and detached house)appears big difference. Therefore, we must completely follow the meter-rate system of food waste to reduce the bad smell intensity of storage container of food waste. Also, we must use verified products in order that quality of exclusive storage container prohibits leakage of bad odor. And then, we must periodically clean the storage container and sterilize it. In addition, when we discharge food waste, we must decrease moisture content to squeeze included water. Also, we must make an effort to reduce storage period , as much as possible. And then, it is necessary to prepare countermeasure about this.

음식물류 폐기물은 높은 수분 및 유기물 함량으로 인해 쉽게 부패되며, 그 과정에서 TVOC 및 황화수소 등 많은 종류의 악취와 다양한 미생물들이 발생한다. 황계열 및 TVOC 와 같은 악취물질은 수거용기 내부에서 발생하여 생활악취 민원의 주요 원인이 되고 있다. 또한 음식물류 폐기물을 버리고 부패되는 과정에서 부유미생물이 발생하여 병원성 세균감염 및 알레르기를 일으킬 가능성이 있다. 따라서 음식물류 폐기물의 악취 및 부유미생물에 대한 대책이 시급한 상황이나 이에 대한 연구는 미흡한 실정이다. 음식물류 폐기물에서 발생하는 악취 및 부유미생물은 계절, 기온, 재료에 따라 많은 차이가 생겨 처리장치의 설계인자를 도출하거나 성능을 정량적으로 평가하기에 어려움이 있다. 따라서 처리장치의 설계 및 성능평가를 위해 성상이 비교적 일정한 표준화 된 음식물류 폐기물의 제조가 필요하며 본 연구에서는 서울시에서 규정한 ‘음식물쓰레기 감량기기, 종량기기 가이드라인(2014)’의 중량비율을 참고하여 채소류, 과일류, 곡물류, 어육류 및 함수율을 조정하여 표준화 된 음식물류 폐기물을 제조하였다. 제조한 음식물류 폐기물의 부패기간에 따른 TVOC 및 복합악취, 부유미생물의 발생 경향을 파악함으로써 처리장치의 기초설계 인자를 도출하고자 하였다. 실험실에서 제조한 음식물류 폐기물의 부패기간에 따른 악취 및 부유미생물의 농도 변화를 측정하기 위하여 12시간 간격으로 TVOC, 복합악취, 부유미생물의 농도변화를 관찰하였다. 실험결과 TVOC, 복합악취, 부유미생물 농도가 60시간까지 지속적으로 증가하였으며 최대농도는 TVOC 86 ppm, 복합악취 3000배, 부유미생물 2517 CFU/m³로 측정되었다. 그리고 72시간 부패 후 TVOC 농도는 84 ppm이 측정되어 소량 감소되었지만 복합악취와 부유미생물의 농도는 복합악취 1000배, 부유미생물 1700 CFU/m³로 측정되었으며 확연히 감소되는 경향을 볼 수 있었다.