This study investigated the effect of NH4 + concentrations on microalgae growth by appling mixotrophic microalgae chlorella vulgaris in order to treat anaerobic digested food waste leachate. The growth rate and final microalgae growth were an order as 400 > 100 > 800 > 1300 mg-N/L. As results, The growth rate and final growth of microalgae were highest at ammonia concentration of 400 mg-N/L, On the other hand microalgae growth was inhibited when ammonia concentrations were over 800 mg-N/L. high concentrations of nitrogen over 800 mg-N/L interrupt the growth of microalgae. All of nitrogen and phosphorus were removed by microalgae at the ammonia concentration of 100~400 mg-N/L. In addition, when ammonia concentration was over 800 mg-N/L, the removal of nitrogen and phosphorus was limited mainly due to the microalgae growth limit. It was possible to treat anaerobic digested food waste leachate with mixotrophic microalgae when the ammonia concentration was controlled below 400 mg-N/L.

In this study, the experiment was carried out to produce methane by applying Semi-Continuous Leachate Recirculation Anaerobic Digestion System fed with source separated food waste from school cafeteria. There were two systems and each system consisted of a bioreactor and a leachate tank. Each bioreactor had a screen near the bottom of the reactor. 2L of Separated leachate was collected to the leachate tank each day by using a tubing pump and the leachate from the leachate tank was pumped to the bioreactor at the upper of the bioreactor. Through this circulation, the leachate having high concentration of VFAs was supplied to the bioreactor. At the beginning of the experiment, food waste/inoculum anaerobic sludge volume ratio was 2:8 that is 9g VS/L of OLR(Organic Loading Rate). Feeding was conducted every two weeks. Initial conditions of bioreactor was 30g VS/2･week and 33g VS/2･week were fed to bioreactor A and bioreactor B, respectively. Average biogas yields of the bioreactor were 0.723m³ Biogas/kg VS added in reactor A and 0.648m³ Biogas/kg VS added in reactor B.

The purpose of this study was to evaluate the applicability of the microbial fuel cell for the combined treatment of food waste water and landfill leachate. Contents of the study was to develop a carbon-containing electrode material radially to maximize microbial attachment. Also to evaluate the electric energy production efficiency by combining the electrode surface coating technology. By using a microbial fuel cell organic matter and nitrogen removal efficiency is evaluated for the food waste water and landfill leachate. BET to evaluate the surface characteristics of the developing electrode (Brunauer Emmett Teller) To evaluate the coating adhesion through measurement and to evaluate the adhesion characteristics micro-organism Weighing. Excellent electrical conductivity in the development electrode platinum, cobalt, by coating a catalyst such as palladium and to evaluate the electric energy generation efficiency. Lab. scale reactor capacity is a 5 L, and to configure the cross-section and the oxidizing electrode as cathode sequentially added.

There is about 80% organic acid in the Food wastes leachate and organic acid can be used as organic carbon source for mixotrophic microalgae. The mixotrophic cultivation is that the combination of autotrophic and heterotrophic cultivation, where inorganic and organic carbon sources are used in their methabolism simultaneously. Therefore, this study investigated the effect of various organic acid on the microalgae when Food wastes leachate treatment. Chlorella vulgaris was used in this study, also NaHCO3 is supplied at all conditions as inorganic carbon source. In order to see the effect of organic carbon sources centrally, the carbon source conditions was set in 5 conditions - glucose known to have excellent effectiveness to increase of biomass productivity 1500 mg-COD/L, acetate 1500 mg-COD/L, isobutyrate 1500 mg-COD/L, propionate 1500mg-COD/L and the mixed organic acid (acetate, isobutyrate, propionate each 500 mg-COD/L). This study evaluated final biomass production, consumption of organic carbon, and N,P removal. In the result, the final biomass productivity by using glucose, acetate and isobutyrate is the highest level, followed by mixed organic acid and propionate. This is same aspect in N,P removal; the more rapid growth rate is, the more rapid N,P removal rate is. In the view of consumption of organic carbon, acetate make best use among organic acid.

This study was to select five places among apartment houses (apartment), detached houses (including houses, villas), downtown area (markets, shops, restaurants) being operated in Korea and use the analysis of physical and chemical characteristics for treatment residues of weight reduction equipment as basic data. Also, we were to evaluate the recyclability by determining whether discharged treatment residues are available in the thermochemical process such as cement sintering facilities and power plants in which energy can be recovered based on the quality standards of Bio- SRF and SRF. Three components for food waste were analyzed and as a result, moisture average, combustibles average and ash average were found to be 11.9% (2.0 ~ 24.8%), 78.9% (63.3 ~ 93.0%) and 9.2% (5.0 ~ 11.9%) respectively and all of them were found to satisfy less than 25%, the moisture content standard of Solid Refuse Fuel (SRF) products. The results of the elemental analysis were analyzed to be carbon average 49.71% (48.41 ~ 52.14%), hydrogen average 6.62% (31.32 ~ 40.63%), oxygen average 37.92% (31.32 ~ 40.63%), nitrogen average 3.82% (2.79 ~ 5.81%), sulfur average 0.26% (0.19 ~ 0.46%), chlorine average 1.67% (1.10 ~ 3.16%). In addition, the low-heating value measurement result is average 4,016.6 kcal/kg (3,255.9 ~ 4,657.9 kcal/kg) and turned out to satisfy most general Solid Refuse Fuel (SRF) product standards but that of Facility E is 3,255.9 kcal/kg and was analyzed not to meet the quality standard 3,500 kcal/kg. However, if maintaining the moisture content of treatment residues to 20% or less, it is determined to satisfy the caloric value standards of general Solid Refuse Fuel products.

This paper describes the performance of the module-type drying apparatus for the composting of a food waste. The drying apparatus mainly consists of a screw-type food waste agitator, an air exhaust blower, a heat supply tube and a heat source. Two different discharging flow conditions of the drying apparatus, 4 and 5 m3/min, are introduced. Partly dried by-products after six hours drying operation in the drying apparatus is obtained while drying temperature keeps constant of 60oC. It is noted that the by-products needs to sufficient decay period for the composting. Deodorizing apparatus having a zigzag flow and a nozzle, which is connected to the drying apparatus, is also designed to enhance the removing performance of the odor. Throughout experimental measurements, time to the drying temperature of 60oC near the screw-type food waste agitator is shortened as discharging flow rate of the system decreases. The moisture content decreases to 50 percent after operation for 4 hours. Furthermore, the odor of the food waste is satisfied with the environment exhaust standard through the deodorizing apparatus.

This study was initiated to examine the potential impacts on the environment during the management of food waste by anaerobic digestion in Daejeon Metropolitan City (DMC) that is built in 2017. The evaluation was based on both material flow analysis (MFA) and life cycle assessment (LCA). The MFA study was performed using STAN 2.5, while the LCA was conducted according to ISO standards by utilizing Total 4 LCA software with the incorporation of CML 2002 methodology. According to the LCA results, global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), and photochemical ozone creation potential (POCP) were found to be approximately 166 kg CO2-eq/ton of food waste, 0.43 kg SO2-eq/ton of food waste, 0.66 kg PO4 3−eq/ton of food waste, and 0.08 kg C2H4-eq/ ton of food waste, respectively. The disposal stage showed higher impact of GWP on the environment due to the landfilling of solid sludge and screening waste. In case of eutrophication potential, the treatment phase showed the highest impact on the environment, mainly because of the consumption of electricity. Based on the results of normalization, the highest environmental impacts was found in the treatment stage related to eutrophication potential. The results of LCA would provide policy-makers to identify and reduce potential environmental impacts associated with food waste to biogas conversion in DMC by life cycle.

Food waste, a putrescible form of waste, comprised of 30% of the total municipal solid waste stream in Daejeon Metropolitan City (DMC) in 2012. Proper management of food waste is a challenging task for local government. This study was conducted to determine material flows when treated food waste in various recycling facilities. Material flows in the recycling processes were collected by site surveys, field trips and discussion with operators and governmental employees. Material flow analysis (MFA) was conducted to quantify the flow of food waste from generation to disposal for the year 2012. MFA along with its mass transfer coefficients were determined based on the inputs, outputs and waste fluxes. According to the mass transfer coefficient results, treatment efficiency for the dry and wet feed manufacturing facility was found to be higher than other treatment facilities. Water consumption was higher for the composting site, resulting in large volume of wastewater (mass transfer coefficient 1.539). While large amounts of screening materials such as plastic, chopsticks, aluminum foils, and bottle caps were generated at the composting site, mass transfer coefficients (0.312) at the dry and wet feed facility were relatively high, implying effective treatment of food waste occurring. The results of this study help to facilitate waste management policy decision-makers in developing effective food waste management techniques in DMC.

In this study the effects of co-digestion of sewage sludge and food waste leachate on the anaerobic digestion efficiencyfrom sewage treatment facilities in S. Korea were investigated. For this study 15 facilities were selected including 9facilities treating sewage sludge only (S-Only) and 6 facilities treating sewage sludge and food waste leachate (S-MIX).The average volatile solid (VS) removal rate of S-Only was 30.7% and that of S-MIX was 45.2%. The COD removalrate of S-MIX (61.3%) was higher than that of S-Only (48.6%). It has been observed that the anaerobic digestion efficiencyof S-MIX was superior to that of S-Only because S-MIX contained more sufficient nutrient with higher VS contents andtotal solid (TS) contents emerging from food waste leachate. Therefore food waste leachate addition in sewage sludgeanaerobic digestion would be the preferred option to treat only sewage sludge.

This study was performed to evaluate the drying characteristics of food waste in oil vacuum evaporation system withdrying conditions and composition of food waste. The food waste was collected and separated into 4 categories such asvegetables, fruits, grain (rice), meats and others. which composition were 41.9%, 26.7%, 2.8%, 25.5% and 0.4%,respectively. Each food waste separated was dried and compared its characteristics in the same condition of vacuumpressure (−450mmHg), temperature (110oC) and mixing ratio (oil:food waste=1:1) for 90min of drying period. Theexperimental results showed that the moisture contents of dried vegetables, fruits and meats were less than 10%. Howeverthe grain was hard to be dried which moisture content was much high as 24.5%. This high value of the grain was thoughtdue to the viscosity of grain which prohibit oil penetration and water vaporization during drying process. In order tocompare drying characteristics with operating parameters, vacuum pressure, temperature and mixing oil type were changed.The operating temperature and vacuum pressure were major sensitive parameters. As the temperature increase and thepressure lower, the drying rate of food waste was increased and its efficiency was also improved. Especially, the moisturecontent of dried food waste was lower than 5% which was satisfied SRF standard 10% at the temperature over 110oC.Compared the effect of mixing oil type, waste cooking oil was more effective than refined oil in viewpoint of dryingefficiency. However, there is no difference of drying efficiency between fresh and waste cooking oil.

Anaerobically treated food wastewater still contains high concentration of organic carbon and nitrogen. Consequently,subsequent treatments are needed to meet the effluent criteria of wastewater. Injection of treated food wastewater into awaste landfill body could be one alternative for its subsequent treatment. In this study, preliminary experiments wereconducted to inject treated food wastewater into waste landfill body. Firstly, Biochemical Methane Potential (BMP) testwas conducted to evaluate the methane generation potential of the injected food wastewater. Secondly, anaerobicallytreated food wastewater showed clogging problem during the initial stage of laboratory scale lysimeter injectionexperiment. Accordingly, pretreatments were needed, and we experimented the change of viscosity of the wastewater afterchemical injection (1N acid or base solution) or aeration of wastewater. From the results, BMP for the treated foodwastewater showed 373.8mL CH4/g VS, which was 53% of untreated food wastewater’s. Practically feasible solution toreduce the viscosity of treated food wastewater was 1 day aeration before injection into the waste landfill body.

In this study, waste landfill site was used as a bioreactor landfill for the treatment of anaerobically digested foodwastewater, and a basic study on waste landfill injection of anaerobically digested food wastewater was conducted. To studythe effect of different operating condition on the quality of lysimeter leachate, 3 lysimeters were operated at differentcondition (i.e., Lys 1=no recirculation, Lys 2=leachate recirculation, Lys 3=leachate recirculation after one day aeration),and the results of leachate quality were as followings. pH Level of leachate became similar to the digested food wastewaterafter 63 days of operation(equivalent to the 11.2% of bed volume) and Cl- concentration of leachate was higher than injectedfood wastewater during whole 6 months of operation period. Leachate COD showed stable values after 70 days of operation,and reduction rate of COD concentration after 6 months was 86%, 89, and 90% for Lys 1, Lys 2, and Lys 3, respectively.The reduction rates of TKN concentration were 19, 28, and 65% for Lys 1, Lys 2, and Lys 3. Lys 3 showed the mosteffective TKN reduction. Leachate recirculation after one day aeration resulted effective reduction of cumulative COD andTKN mass, which were 61% and 40% respectively, compared to the no recirculation case.

In spite of the government's various efforts to reduce food waste, the food waste in Korea has increased about 3%every year, mainly due to the growing population, number of households, and income. Food waste occurs in the processesof production, transportation, distribution, storage and cooking of food ingredients. However, there has been little reliabledata about how households - a major food waste source - store and treat their food and how much food waste they produce.In this regard, we thought it was important to understand the exact amount and characteristics of food waste fromhouseholds in order to reduce the country's food waste, which is why we monitored kinds, storage periods, treatment,and waste of food consumed in 100 households in the Seoul metropolitan area. Households normally store their foodingredients in refrigerators - on average 33 kinds and 35kg of food are stored - and some of them stayed there for upto 3 years. Moreover, not a small portion of the food is thrown away nearly untouched, mostly because people tend topurchase too much food at one time or they don't know or miss their expiration dates. The amounts of food waste bytype were in the order of vegetable>side dish>frozen food>fruit>seasoning. Also, we suggest effective and realisticmeasures to reduce food waste and promote a more desirable food consumption culture.

For the practical feasibility of lactic acid (LA) fermentation process, a continuous operation using mixed culture and the use of cheap and non-food raw materials are essential. In this study, a continuous LA fermentation of food waste was attempted using indigenous mixed culture. During the operation, temperature was gradually increased from 35℃ to 55℃, with showing the highest performance at 50℃. At 35-45℃, other organic acids such as acetic acid and butyric acid were also observed. At 50℃ and HRT 1.0 d, both LA production yield and its productivity were maximized to 1.8 mol LA/mol hexoseadded and 1.4 g LA/L/hr, respectively. A pyrosequencing result showed that Lactobacillus amylolyticus was the predominant species performing LA fermentation of food waste. The combined process of nanofiltration and water-splitting electrodialysis could recover highly purified LA from the fermentation broth by removing 95% of mineral ions and 77% of ammonium and glucose.

This is aim to use and recycle the wasted biogas from the dispose process of the food wasted facility in Dae-Gu. Furthermore, the virtuous biogas is to be supplied for the Industrial Complex as energy resource. It is to develop the system for Pre-treatment and High-efficiency of the wasted biogas that includes low concentration and impurities. The Pre-treatment is to remove Siloxan, Hydrogen sulfide, Carbon dioxide, Oxygen and etc. which might influence to end-users in negative way. The High-efficiency system is to remove moisture in Biogas and increase the purity for keeping the constant concentration Methane for useful resource with measuring the portion and density in real time. It shows that constant above 60% Methane gas is possibly to be supplied to end-users as a alternative energy resource rather than using LNG, LPG and etc. for their own boilers system. It is expected that there are Environmental, Economical and Social effects with establishing optimum network for the reuse of Biogas. Environmental positive effects are to reduce the Global Warming Potential, use fossil fuel and Green-house gases. Economically it will bring down the production cost of end-users by using the pre-treated biogas. Furthermore, the alternative energy resource is to be secured and New R&D Study might be applied with FuelCell Power Plant, Hydregen Station and Hydrogen Reforming in social effects.

Waste activated sludge (WAS) and food waste (FW) are available year round at low cost and have the potential to promote synergism in anaerobic digestion (AD). The goal of this study was to clarify the synergism in co-digestion of WAS and FW. A slight amount of FW at various ratios was added to WAS as an auxiliary substrate, and anaerobic batch tests were performed under mesophilic conditions. By adding FW, total CH₄ produced was increased, where most of them were come from WAS, clearly suggesting synergism. Also, lag period was shortened and CH₄ production rate was increased by FW addition. It was hypothesized that enhanced performance was owing to the facilitated hydrolysis of WAS by FW addition, which was revealed by the increased activities of hydrolytic α-amylase and protease.

Food waste, food leachate and livestock wastes from an usual farm and a farm using much disinfectant were mixed to incubate within anaerobic serum bottle for BMP test. The methane yield rate and lag phase were determined by the modified Gompertz model and the Logistic model. The maximum methane yield rates by the modified Gompertz model were 15.9 ~ 41.0 mL CH4/g VS and higher than by the Logistic model. The modified Gompertz model was more appropriate than the Logistic model to have higher determination coefficient R2. The methane fermentation of mix with sole livestock waste from the farm using much disinfectant had ninefold lag phase and 40% or lower maximum yield rate comparing with the mix with sole usual livestock waste. The methane yield rate from a tonne of mix was increased as the ratio of food waste and food leachate increased. The cumulative methane yield was in the proportion of 40 m3 to a tonne of food wastes. The results of BMP test were analyzed by a response surface methodology (RSM) and modelized to a binomial expression, which was verified by analysis of variance (ANOVA) and to be appropriate for this case.

A food waste disposer is an electrically powered device installed under a kitchen sink. It is located between the sink’s drain and the trap which shreds food waste into tiny pieces so that they can go through plumbing. Use of this unit is convenient and hygienic for discharging food waste in kitchen. Nevertheless, this unit has been illegal until now in Korea because of both conflict with the government’s policy-resource recovery from food waste-and perceived threat to the city’s sewer system. An attempt was made recently to meet growing need to introduce this unit for advantage of using disposer and maintenance of sewer system, etc. So an attempt was made to introduce the food waste disposer system of ‘treatment type before discharging to sewer’, but it was inappropriate for conditions in Korean. In this study, we developed a suitable disposer system for Korea based on an innovative solid recovery technology. And continuous operating experiments were carried out to evaluate the performance of the system for 18 days. The amount of food waste fed into the system was equivalent to the daily amount of food waste made from 30 households living in apartment units, which was calculated to be 14.44 kg/day. After grinding, SS/TS of food waste was 60 percent and it was the maximum amount of solid that could be recovered using this system. In the system of solid collection type using screw press, more than 70 percent of suspended solids were recovered. And less than 20 percent of total soilds were discharged through wastewater and it satisfied the legal standard of Korea. This novel food waste disposer system will satisfy with both the government’s environmental policy and higher quality resource recovery from food waste in the facilities.

Batch cultivations were performed to evaluate the influences of the initial pH condition on mesophilic and thermophilic acidogenic fermentation with food waste recycling wastewater. In both conditions of mesophilic and thermophilic fermentation, TVFAs production rates were maximized at the initial pH 7 condition as 0.15 and 0.23 g TVFAs/L·hr, respectively. And pH was also maintained stably between 6 and 7 during 72hr acidogenic cultivation at both conditions. However, predominant VFA components were different according to reaction temperature conditions. In mesophilic condition, propionic acid which has low conversion efficiency to methane was accumulated up to 1,348 mg/L while acetic and butyric acid were predominant in thermophilic condition. Therefore, thermophilic acidogenic fermentation was superior for the effective VFAs production than mesophilic condition. From the DGGE analysis, the band patterns were different according to the initial pH conditions but the correlations of the each band were increased in similar pH conditions. These results mean that microbial communities were certainly affected by the initial pH condition. Consequently, the adjustment of the initial pH to neutral region and thermophilic operation are needed to enhance acidogenic fermentation of food waste recycling wastewater.