• Journal of the Korean Institute of Gas
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• v.22 no.2
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• pp.46-51
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• 2018

Hydrogen sulfide from landfill and sewage treatment plant is a major odor component and causes many civil petitions. Rapidly developing industries release hydrogen sulfide, an odorous gas, to the atmosphere. This study aims to develop a $10{\mu}mol/mol$ concentration level hydrogen sulfide primary standard gas for odor measurement. The hydrogen sulfide gas was prepared at a nominal concentration of $10{\mu}mol/mol$ in nitrogen using the gravimetric method described in ISO 6142. Replicate standard gases were produced in 4 aluminium cylinders, and their concentrations were verified by GC-AED. The uncertainty of production was less than 0.50 %, and the variation of the 4 replicates was 0.22 %. The wall adsorption of hydrogen sulfide in cylinders was 0.10 % at 1500 psi, and the concentration was estimated to be long-term stable for one year. The relative expanded uncertainty of the preparation consistency, adsorption and long-term stability of this hydrogen sulfide standard gas was less than 1.05 % (95 % of confidence level, k=2).

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.2
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• pp.15-29
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• 2020

The aims of this study is to improve physical properties of the sewage sludge and the process sludge generated in the leachate treatment by mixing the dry fuel, to develop the neutral solidifing agents that reduce oder, and to recycle the sewage and the process sludges as landfill cover materials. The mixing ratio (W/W) of sludges and dry fuel was appropriate at about 1:1, and the mixed materials were shown to be homogeneous at that ratio. We could know that when the sludges were mixed with dry fuel, moisture contents and viscosities are reduced, and air passages are formed between particles and particles. The various mixing tests and odor tests showed that the neutral solidifing agent was effective for the odor reduction. The main ingredient of the solidifing agent is the ash of sewage sludge, enabling it competitive in waste recycling and production costs. The landfill cover, using developed neutral solidification agent, improved physical properties to satisfy the quality standards and to increase the compressive strength. It also proved to reduce the value of complex oder and the usage of solidification agent to 1/3 (3,000 to 1,000) and to 1/8 (50% to 6%), respectively, from the comparative study with alkaline solidified landfill cover. Further research is under way to prove that this can be mixed with general soil to be used as a soil improvement agent for plant cultivation.

• Journal of Animal Environmental Science
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• v.11 no.1
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• pp.55-60
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• 2005

This study was conducted to determine the odor reduction efficiency of a biofilter desist using different filter materials. The summary of results are as follows; 1. The airflow penetration rate of the different filter materials namely; rice straw, woodchips, rice hulls and sawdust were 0.72 m/s, 0.64 m/s, 0.48 m/s and 0.17 m/s, respectively. 2. The elimination of $NH_3$ gas was fastest in the rice hull at a rate of 4 mg/${\iota}$ followed by sawdust, woodchips and rice straw at 3 mg/${\iota}$, 3 mg/${\iota}$ and 7 mg/${\iota}$, respectively. 3. The filter material made of wood chips was able to eliminate the offensive gas known as $H_2S$ at a rate of 2.2 mg/${\iota}$ on the 7th day, 17.6 mg/${\iota}$ on the 21st day but decreased to 10.7 mg/${\iota}$ on the 36th day. In contrast, the filter material composed of sawdust had a continuous increase in the reduction of $H_2S$ at a rate of 12.3 mg/${\iota}$ on the 7th day, 18.3 mg/${\iota}$ on the 21st day and 20.1 mg/${\iota}$ on the 36th day. The above findings indicated that among the filter materials, sawdust was the most effective in absorbing $H_2S$. Airflow penetration rate can be related to $H_2S$ odor elimination efficiency as shown by the slowest airflow rate of sawdust which is only 0.17 m/s.

• Culinary science and hospitality research
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• v.7 no.3
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• pp.145-161
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• 2001

In odor to develop fillet-type seasoner and mixed powder-type seasoner using smoked mackerel as primary material, processing conditions of the mackerel meat and flavoring extract from various materials were examined. The approximate composition of mackerel meat and mixed powde-type seasoner using mackerel as primary material were 10.9 and 11.7%, for moisture 79.1 and 57.2% for crude protein, 5.3 and 2.9% for crude lipid, and 4.3 and 24.6% for crude ash, respectively. It was suitable to simmer raw mackerel in 3% chitooligosaccaride solution at 8$0^{\circ}C$ for 10 min., for the enhancement of reaction their meat and chitooligosaccharide. Considering effect of type of woodsmoke on organoletic properties of mackerel after smoking, oak and mixture(oak wood ＋ citrus wood = 1 : 1) were superior to another woodsmoke, the smoking conditions favoring the most overall preference were 8$0^{\circ}C$, 25min. for smoking time, 20$0^{\circ}C$, 20min. for baking, and 10$0^{\circ}C$. 4hrs. for drying. The optimal material mixing ratio for mixed powder-type seasoner was powder of smoked mackerel 60%, dried anchovy 15%, dried sea tangle 10%. The most appropriate extraction condition of mixed powder seasoner with packing tea bag(10g/bag) was 98$^{\circ}C$ for 5min. in the boiling water.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.372-377
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• 2007

In order to assess its capability as biofilter bed material under variable conditions of two parameters (inlet gas concentration and inlet gas flow rate), reticulated polyurethan was applied to remove hydrogen sulfide via a biological process. We detected a maximal elimination capacity (critical loading rate) of $488.3(330.1)g-H_2S/m^3{\cdot}hr$, when reticulated polyurethane was employed as supporting material of biofilter. This study show that the application of reticulated polyurethane carrier might be a favorable choice as a packing material in biofilter for the biological removal of hydrogen sulfide.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.817-828
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• 2023

Deteriorating soil physical properties and increasing soil pathogens due to the continuous cultivation of field crops are the leading causes of productivity deterioration. Crop rotation, soil heat treatment, and chemical control are used as pest control methods; however, each has limitations in wide application to domestic agriculture. In particular, chemical control requires improvement due to direct exposure to sterilizing solution, odor, and high-intensity work. To improve the overall domestic agricultural environment, the problems of time and cost, such as field maintenance and cultivation scale, must be addressed; therefore, mechanization technology for chemical control must be secured to derive improvement effects in a short period. Most related studies are focused on the control effect of the DMDS (dimethyl disulfide) sterilizer, and research on the performance of the sterilization spray device has been conducted after its introduction in Korea, but research on the corrosion suitability of the material is lacking. This study conducted a corrosion test to secure the corrosion resistance of a soil sterilizer injection pump, and a mechanical failure mode by corrosion by the material was established. The corrosion test comprised operation and neglect tests in which the sterilizing solution was circulated in the pump and remained in the pump, respectively. As a result of the corrosion test, damage occurred due to the weakening of the mechanical strength of the graphite material, and corrosion resistance to aluminum, stainless steel, fluororubber, and PPS (polyphenylene sulfide) materials was confirmed.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.5
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• pp.316-325
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• 2012

In this study, we suggested adequate control technology by analyzing emission process and main chemical of VOC/HAPs generated from four paint factories in Busan area. And we estimated whether Kapok fiber, which is a natural material, can be commercially used for an absorbent by testing adsorption ability. As a result of this sturdy, above 60% of VOC/HAPs was volatilized and dispersed inside the working place without conducting control system of facilities during manufacturing paints. Concentration profile of VOC/HAPs, which is volatile naturally outside the factories, is surveyed above 70% at Toluene, Ethylbenzene, and Xylene. And a result of evaluation of odor attribution level about the component whose Odor Threshold is known, it is estimated that major cause material of A, B, C factories is Toluene and that of D factory is m/p-Xylene. And that result presented design arguments such as facilities specifications, activated carbon filling volume, and replace cycle of activated carbon as control technology. Also, that result presented emission process improvement such as adsorption of central-controlled ventilation device, installation of inlet flenge, and potable cleaning process. The rate of pollutant adsorption of Kapok fiber, which is natural material, is indicated about 91.9%, 66.7%. That result validated the possibility as replacement of activated carbon.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.856-865
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• 2012

Maintenance systems are demanded to manage malodor-information and deal effectively with the odor-related civil complaints by constructing the database for sources of malodor compounds in real time. In this paper, to carry out these tasks, a real-time monitering system for malodor based on ubiquitous sensor networks(USN) is presented. The constructed monitering system stores the malodor data collected periodically from industrial complex into the database and shows in real time the circumstances of the odor sources being emitted around the industrial complex by indicating on the map where it is taking place. Besides, by clicking an icon indicating the sensor node on the map, we can figure out what firms are located near the malodor source and possible material related with those firms. The proposed system is considered to enhance the efficiency of management of malodor-emitting firms based on the malodor-related information.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.5
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• pp.325-331
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• 2009

This study was performed to evaluate characteristics of algal occurrence in Lake Paldang. Chlorophyll a concentration was highest during spring, based on weekly measurements from 2006 to 2008, which revealed a different trend compared to the data before 2000 that showed the highest level during summer. Total algae cell quantity was also highest during spring, based on monthly data. Overall, Bacillariophyceae was dominant and represented 87% of total algae cells and occupation was more significant during spring and winter. Cyanophyceae was dominant during summer. 2-MIB and geosmin originating in algae which caused odor problems was high in July 2008, and more research on the relationship between algae and production of odor causing material is needed.

• Journal of Environmental Health Sciences
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• v.31 no.4 s.85
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• pp.309-315
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• 2005

Volatile organic compounds (VOCs) and odor materials are major sources of air pollution in Ulsan city, where much chemical plants are located. Therefore, it is necessary to develop a new reactor which can remove VOCs and odor materials effectively and be equipped at the end of pipe easily. A modified reactor (bioscrubber trickling filter, BSTF), which have both characteristics of biofilter and bioscrubber, was developed and tested on its reactivity with several VOCs using two types of media, fiber and activated carbon 4- ceramic(A/C). It was observed that the removal efficiencies of several types of VOCs such as acetaldehyde, ethylalcohol, butanol, diethylamine and triethylamine were up to $95\%$ when they had about 100 ppm of initial concentration and 80 seconds of residence time. Good attachment of microorganisms to both media, where it is thought the reaction efficiency can be determined according to the amount of microorganisms attachment, observed with scanning electron microscopy(SEM). Initial pressure drops of the packed bed with both media were 229 $mmH_2O/m$ at A/C column and 670 $mmH_2O/m$, respectively. However, maximum pressure drop of fiber column during the operation was over 1,647 $mmH_2O/m$. Therefore, it was thought that the fiber material would not suitable to use in the local plant as a packed bed media.