• Advances in environmental research
• /
• v.7 no.2
• /
• pp.73-85
• /
• 2018

The anaerobically digestion and agricultural application of organic wastes was conducted using food wastes and cow dung. Twenty kilograms each of the feed stocks was added into two 30 liters-capacity batch digesters. The anaerobic digestion was carried out within a temperature range of $25-31^{\circ}C$ for a retention time of 51 days. The results showed a cumulative gas yield of 5.0 bars for food waste and no gas production for cow dung within the retention time. Bacteria such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris and Clostridium sp were isolated. Fungi isolated included Aspergillus niger, Aspergillus nidulan, Trichophyton rubrum and Epidermophyton flocossum. The non-dispersive infrared (NDIR) analysis of the biogas produced confirmed that the gas consisted of $CH_4$, $CO_2$ and $H_2$. Statistical analysis revealed there was no significant correlation between temperature and biogas produced from the organic wastes (r= 0.177, p = 0.483).The organic wastes from the biogas production process stimulated maize growth when compared to control (soil without organic waste) and indicated maximum height. The study therefore reveals that food waste as potential substrates for biogas production has a moderate bio-fertilizer potential for improving plant growth and yield when added to soil.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.25 no.2
• /
• pp.77-90
• /
• 2017

In order to promote recycling of animal and plant residues, it is necessary to prepare detailed statistics on the sources, generation amount and the state of disposal so that waste recycling companies and enterprises can obtain the information easily. Also, the recycling methods specified in the law should be appropriate. For this, the study reviewed the appropriateness of detailed classification of animal and plant residues and permitted recycling methods in the Enforcement Regulations of the Waste Management Act of Korea. For improvement of the detailed classification, the study conducted literature review on European and Japanese ones. Additionally, we visited slaughterhouses of livestock and poultry, vegetable oils manufacturing companies, starches and glucose or maltose manufacturing companies, which generate the waste and recycle the waste, to grasp the status of recycling in Korea. Based on the results, the study proposes improvement measures for the detailed classification and the permitted recycling types in the law.

• Journal of Environmental Health Sciences
• /
• v.38 no.2
• /
• pp.151-158
• /
• 2012

Objectives: Bioaerosols released by treating organic-waste resources cause a variety of environmental and hygiene problems. The objective of this study was to investigate the distribution characteristics of the airborne bacteria emitted from a pig manure composting plant, a principal site for organic-waste resource facilities. Methods: Three types of pig manure composting plant were selected based on fermentation mode: screw type, rotary type and natural-dry type. Each site was visited and investigated on a monthly basis between September 2009 and August 2010. A total of 36 air samplings were obtained from the pig manure composting plants. The air sampling equipment was a six-stage cascade impactor. Quantification and qualification of airborne bacteria in the air samples was performed by agar culture method and identification technique, respectively. Results: The mean concentrations of airborne bacteria in pig manure composting plant were 7,032 (${\pm}1,496$) CFU $m^{-3}$ for screw type, 3,309 (${\pm}1,320$) CFU $m^{-3}$ for rotary type, and 5,580 (${\pm}1,106$) CFU $m^{-3}$ for natural dry type. The screw type pig manure composting plant showed the highest concentration of airborne bacteria, followed by the natural dry type and the rotary type. The ratio of respirable to total airborne bacteria was approximately 40-60%. The predominant genera of airborne bacteria identified were Micrococcus spp., Staphylococcus spp. and Escherichia spp. Conclusion: Monthly levels of airborne bacteria were highest in August and lowest in November regardless of fermentation mode. There was no significant correlation relationship between airborne bacteria and environmental factors such as temperature, relative humidity and particulate matters in pig manure composting plants.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.11 no.2
• /
• pp.97-109
• /
• 2003

This study was conducted to investigate use possibility on waste water sludges of water disposal plant as raw materials of organic compost at Fertilizer Official Regulation of Fertilizer Management Law in 2002. In heavy metal contents, some water service sludges were discovered a little over than the standard levels of raw material regulated in organic compost and most of them were not reached the levels. But they were difficult for using the raw materials of organic compost owing to shortage of the organic content. It was judged that the fiber and leather sludges were much in the heavy metal contents and they couldn't use as the raw materials of organic compost. There was afraid that a little heavy metal contents of cosmetic sludge were less than the levels, but it was possible to use selectively as a raw material.

• Korean Journal of Organic Agriculture
• /
• v.11 no.1
• /
• pp.55-66
• /
• 2003

This study was carried out to investigate the effects of different plant growth media on the growth of tomato(Lycopersicum esculentum Mill.) seedlings during growth stages. The media were commercial plant growth medium 100％, earthworm cast (that was produced by vermicomposting of food waste and cattle manure) 100％, earthworm cast 50％ ＋ vermiculite 50％, earthworm cast 50％ ＋ perlite 50％, earthworm cast 40％ ＋ vermiculite 30％ + perlite 30％. Plant length(mm), number of leaves, leaf area($\textrm{cm}^2$), stem diameter(mm), plant dry mater were greatest till the 2nd week growth stages in the commercial plant growth medium plots, but those were higher in the earthworm cast than those in the other plant growth media at the later stages of this study(P<0.05). And relative growth rate of biological yield, relative growth rate of shoot and relative growth rate of root were highest in the earthworm cast till the 4th week growth stage. Therefore it can be implied that there is the possibility of potential utilization of earthworm cast, which was produced by vermicomposting of food waste and cattle manure, as vegetable growth medium.

• KSBB Journal
• /
• v.25 no.1
• /
• pp.103-107
• /
• 2010

Oil degradation agent was developed with organic sludge and modified peat moss (MPM) to recover oil contaminated soil. Waste sludge discharged from wastewater treatment plant of chemical plant in Ulsan National Industrial Park was used as organic sludge, and MPM was purchased. Organic sludge was adequate to use as growth medium for microorganism, the surface of MPM had porous structure which could enhance the cultivation condition of oil degradation microorganisms. Water contents and TPH variation with time were observed to investigate the degradation capacity of developed degradation agent. Water contents were rapidly decreased with higher contents of MPM, however, in case of TPH, high MPM content decreased the degradation capacity. Therefore, it was recommended that the content of MPM was controlled to below 10% in degradation agent as mixing organic sludge with MPM.

• Journal of environmental and Sanitary engineering
• /
• v.15 no.4
• /
• pp.91-97
• /
• 2000

The objective of this study was to evaluate the possiblity of Foodwaste and co-treatment with other waste for vermistabilization. The value of oxidation-reduction potential(Eh) of the dewaterized foodwaste by a plant of subatmospheric evaporation was a possitive(+) value indicating, but the values of pH, salinity was idicating an unfavorable condition for earthworm life. The paper mill mixing waste properties by ripening for 20days were changed into the favorable range for earthworm. The growth of earthworms in foodwaste and mixing waste of paper mill 30% was found to be 68%, 84% for the survival rate, 227%, 275% for the liveweight increasing rate, respectively. The ingestion rate of foodwaste and mixing waste of paper mill 30% indicate 0.72g/g·d, 0.81g/g·d, respectively. About 62∼75% of ingestion amount produce cast and characteristics of cast indicate pH 6.1∼6.5 organic component 34∼42%, salinity 0.35∼0.4, CEC 73∼94 me/100g, N, P, K concentration 0.8∼1.2%, 0.4∼1.6%, 0.43∼0.5% respectively. Therefore it can be evaluated that the casts are good soil condition and organic fertilizer.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.25 no.1
• /
• pp.23-33
• /
• 2017

In this study, water and organic treatment efficiency and operating characteristics (temperature, salinity effect) were evaluated when food waste with high water content was treated by Bio-dying method. In addition, the optimum conditions for producing pellets for evaluating the decomposition products as SRF(Solid Refuse Fuel) after Bio-drying and evaluating the use value of SRF as a solid fuel were analyzed. As a result, the temperature, $CO_2$ concentration, organic matter removal rate and weight reduction rate according to the daily dose were about 86% and 68% at the input of 2.4 kg/day. The optimal food waste input was estimated to be 2.4 kg/day. As a result of the pellet molding and produce, Pellets can be produced within 10~25% of raw material water content. It was judged that the water content of 25%, which showed the best quality results in terms of external shape maintenance and strength. The high calorific value of SRF of decomposition products after Bio-drying was more than 3,500 kcal/kg.

• Journal of Environmental Health Sciences
• /
• v.46 no.4
• /
• pp.398-409
• /
• 2020

Objectives: This study aimed to evaluate environmental exposure to tobacco-specific nitrosamines (TSNAs) by conducting an analysis of the concentration of TSNAs in deposited dust collected from a fertilizer plant and the surrounding village, a simulation of high-temperature drying of tobacco waste, and CALPUFF modeling. Methods: The raw materials of the products, deposited dust (inside and outside the plant and residential area), soil, and wastewater were sampled and the TSNA concentrations were analyzed by LC-MS/MS. As the plant was closed down before the investigation, simulation tests were conducted to confirm the substances discharged during high-temperature (300℃) drying of tobacco waste. CALPUFF modeling was performed to identify the area of influence due to exposure to TSNAs. Results: TSNAs were detected in organic fertilizers estimated to contain tobacco waste, deposited dust, and soil collected from inside and outside the plant. N'-nitrosonornicotine (NNN), 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone (NNK), and N'-nitrosoanatabine (NAT) components were detected in five of 15 deposited dust samples collected from the residential area around the plant, while TSNAs were not detected in the five sampling points in the control area. Also, the simulation test for the high temperature drying of tobacco waste found emissions of TSNAs. The CALPUFF modeling results showed that the survey area was likely to be included in the area of influence of TSNA emissions from the plant. Conclusions: It is estimated that harmful tobacco ingredients such as TSNAs were dispersed in nearby areas due to the illegal use of tobacco waste as a raw material to produce organic fertilizers at the plant. These findings assume that the residents have been exposed to TSNAs and suggest that the need for the establishment of measures to manage environmental health.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.24 no.4
• /
• pp.11-20
• /
• 2016

Depletion of natural resources and reduction of greenhouse gas emissions are an important issue which we have to solve. The recycling of waste has emerged as a global concern. In Korea, the development of cost-effective treatment and recycling technologies also need to be improved. In this study, we compared and analyzed the cost per unit of treatment and recycling of organic waste, and presented an effective recycling scheme. We investigated the current status of treatment and costs for six types of organic wastes from 80 workplaces, including organic wastewater treatment sludge, processed organic sludge, and plant residues. In addition, environmental costs for greenhouse gas reduction were calculated. It's an economic way that organic waste is composted and used as cement additives. In particular, the economic analysis was done by realistic results of the survey target companies. In conclusion, in order for reliable processing and recycling of organic wastes, wastewater treatment sludge and sewage sludge need to be classified based on hazard characteristics. Finally, technical difficulties need to be further resolved such as odors, leachate, and debris on recycling organic wastes.