• 한국대기환경학회지
• /
• 제27권6호
• /
• pp.703-710
• /
• 2011

Odor emission from domestic sewer systems has become a serious environmental problem. An investigation on a sewer manhole revealed that anaerobic decay of sediment organic matters (SOMs) and related declines of oxidation reduction potential (ORP) in the sediment layer were the main reason of the production of volatile sulfur compounds. In addition, as the anaerobic decaying period continued, the odor intensity rapidly increased with increasing concentrations of $H_2S$ and dimethyl sulfide. As a feasible method to control SOMs and to minimize odor emission potentials, an electrolytic oxidation process has been employed to the sediment sludge phase. In this study, voltages applied to the electrolytic oxidation process were varied as a main system parameter, and its effects on odor removal efficiencies and reaction characteristics were investigated. At the applied voltages greater than 20 V, the system efficiently oxidized the organic matter, and the ORP in the sludge phase increased rapidly. As a consequence, the removal efficiency of hydrogen sulfide was found to be >99% within 60 minutes of the electrolytic oxidation. Overall, the electrolytic oxidation process can be an alternative to control odor emission from sewer systems, and a threshold input energy needs to be determined to achieve effective operation of the process.

• Journal of Biosystems Engineering
• /
• 제36권5호
• /
• pp.342-347
• /
• 2011

The effect of SNC(silver nano colloid) on the emission reduction of odors such as ammonia ($NH_3$), hydrogen sulfide ($H_2S$), and methane ($CH_4$) from swine excreta was studied. Silver has been used as an universal antibiotic substance and can reduce the emission of some gases by sterilizing action. Therefore, an apparatus which produces SNC was developed and was conducted its performance test. Also, the SNC made by the apparatus was applied to swine excreta sampled from a piggery in oder to find the effect on the reduction of odor emission. An electrolysis apparatus was developed to produce SNC and its capacity was 0.024 ppm/$hr{\cdot}L$. The effects of SNC on the reduction of odor emission from swine excreta were tested for bad smell gases of ammonia ($NH_3$), hydrogen sulfide ($H_2S$) and methane ($CH_4$). For ammonia gas, factorial experiments were conducted to find the effects of concentration and application rate of SNC. The test results for the different concentrations of 20 ppm, 50 ppm, and 100 ppm showed that the more concentration of SNC was increased, the more emission reduction of ammonia gas increased. From the test results about the effect of application rate, the more SNC was applied, the more emission reduction of $NH_3$ increased. In order to reduce the concentration of $NH_3$ below 5 ppm, SNC of 50 ppm is recommended to be applied at an interval of 6 hours, and is mixed with swine excreta in the volumetric ratio of 4:1. For hydrogen sulfide gas, the concentration was decreased as time went by and was reduced rapidly in the first stage of the tests for all applied concentrations of SNC (20 ppm, 50 ppm, and 100 ppm). Especially, when 100 ml of SNC with 100 ppm was applied, emission of hydrogen sulfide gas was reduced rapidly during early 4 hours after the application of SNC. And, concentration of hydrogen sulfide gas was maintained below 20 ppm after 12 hours. For methane gas, t-test showed that there was no significance on the effect of its application for all applied concentrations of SNC. Therefore, it was concluded that the application of SNC on swine excreta had no effect on the emission reduction of $CH_4$.

• 웰빙융합연구
• /
• 제4권4호
• /
• pp.35-41
• /
• 2021

Purpose: The purpose of this study is to identify the causes of odors generated in traditional markets and to suggest appropriate application technologies to solve them. Research design, data and methodology: In order to achieve the purpose of this study, complex malodors, TVOC, and hydrogen sulfide were measured three times at each point in Wonju-city, Gangwon-do using direct-reading odor measuring equipment in Joong-ang Traditional Market's Korean beef Alley, Sundae Alley, and Joong-ang Citizens Traditional Market. Therefore, the average value was compared with the emission standard and analyzed. Results: As a result of the study, complex malodors exceeded the emission standards at all points, and hydrogen sulfide exceeded the emission standards at all except for one point. Conclusions: The odor generated in the traditional market has various causes and low concentration, so it is necessary to reduce the odor by using an appropriate technology.

• KEPCO Journal on Electric Power and Energy
• /
• 제2권3호
• /
• pp.437-445
• /
• 2016

This paper discussed the effect of ammonia concentration adsorbed on fly ash for the ammonia emission as AAFA (Ammonia Adsorbed Fly Ash) produced from coal fired plants due to operation of NOx reduction technologies was landfilled with distilled or sea water at closed and open systems, respectively. Ammonia bisulfate and sulfates adsorbed on fly ash is highly water soluble. The pH of ammonium bisulfate and sulfate solution had significant effect on ammonia odor emission. The effect of temperature on ammonia odor emission from mixture was less than pH, the rate of ammonia emission increased with increased temperature when the pH conditions were kept at constant. Since AAFA increases the pH of solution substantially, $NH_3$ in the ash can release the ammonia order unless it is present at low concentration. $NH_4{^+}$ ion is unstable in fly ash and water mixtures of high pH at open system, which is changed to nitrite or nitrate and then released as ammonia gas. The proper conditions for < 20 ppm of ammonia concentration released from the AAFAs landfilled in ash pond were explored using an open system with sea water. It was therefore proposed that optimal operation to collect AAFA of less than 168 ppm ammonia at the electrostatic precipitator were controlled to ammonia slip with less than 5 ppm at SCR/SNCR installations, and, ammonia odor released from mixture of fly ash of 168 ppm ammonia with sea water under open system has about 20 ppm.

• 웰빙융합연구
• /
• 제4권2호
• /
• pp.19-25
• /
• 2021

Purpose: The purpose of this study is to reduce odor complaints by identifying problems with odor management at the site of the water regeneration center and researching odor management methods. Due to the high population density of Korea, sewage treatment facilities are adjacent to residential and industrial areas. According to previous studies, the main malodor-emitting facilities of sewage treatment facilities were preliminary treatment facilities (2,220 times), sedimentation basins (4,628 times), and sludge treatment facilities (9,616 times). Research design, data and methodology: Compound malodors and designated malodor-producing substances were collected from five site boundaries of the water regeneration center and analyzed according to the official methods to test malodor, and a total of two times (August and September 2020) were conducted. Results: As a result of the measurement, in the green area in front of the center office, compound malodors were detected at a maximum of 8 times and at least 3 times during the dawn time. As for the designated malodor-producing substances, 0.1ppm of ammonia was detected in the green area in front of the center office and the park golf course. This is within 15 times the maximum allowable emission level of compound malodors and within 1ppm of the maximum allowable emission level of ammonia. Conclusions: Even if the dilution rate of the compound malodors did not exceed the maximum allowable emission level, the odor could be recognized, and more research is needed in the future to establish effective reduction measures according to the subjective and individual and seasonal odor characteristics.

• 상하수도학회지
• /
• 제32권5호
• /
• pp.445-451
• /
• 2018

Urban sanitary sewer systems can aid in preventing inundation, and can improve civil health by effectively disposing stormwater and wastewater. However, since sewage odor can cause adverse effects, numerous technical and administrative studies have been conducted for reducing such odor. European countries and the United States of America (USA) built modern sewer systems in the late 19th century, and have since been endeavoring to eliminate sewage odors. Several cities of the USA, such as Los Angeles (LA) that has a separate sewer system and San Francisco (SF) that has a combined sewer system, have produced and distributed odor control master plan manuals. Features common in the odor reduction plans of both these cities are that the odor reduction programs are operated in all the respective local regions and are supported by administrative systems. The primary aspectual difference between the two said programs is that the city of LA employs a sewage air purification system, whereas the city of SF controls the emission of major odor causing compounds. Compared to the existing sewer odor reduction systems of these two cities, South Korea is still in the initial phase of development. Through technical studies and policy implementations for sewer odor reduction, a foundation can be laid for improving the civil health quality.

• 한국환경과학회지
• /
• 제17권5호
• /
• pp.525-535
• /
• 2008

5 public complaint areas against odor in Changwon Industrial Complex were selected and investigated to clear up the cause of the complaint. 16 companies operated in public complaint areas were visited and had a grip of their situation about odor generation and treatment. Two samples at it's site boundary of each company were taken to measure complex odor unit. Complex odor unit at the site boundary of investigated companies in the public complaint areas, for the most part, exceeded standard(odor unit 20) in industrial area. It was due to that this area was not designated as odor control region and that there are also many problems in current laws of Odor Protection Act, Air Quality Act and regional legislation. Accordingly, It will be necessary to revise the related legislation, to organize governance, to financially support the improvement of environmental facilities and to enforce guidance and the regulation rigidly for the odor emission reduction in Changwon Industrial Complex.

• 한국환경보건학회지
• /
• 제44권2호
• /
• pp.169-177
• /
• 2018

Objectives: The emission characteristics of aldehydes were investigated in five industries for the efficient management of aldehydes. Methods: Aldehydes and THC were measured from the stack and boundary of facilities. The relative concentrations and odor contribution of aldehydes were evaluated. Results: The concentrations of aldehydes in the asphalt manufacturing and printing industries were relatively high. Formaldehyde met emission limits for all facilities. According to the odor contribution analysis of aldehydes, i-valeraldehyde and butyraldehyde, which have a relatively low odor threshold value, were found to be the major odor-causing substances in the painting and textile processing industries. Conclusions: Among the aldehydes, the major emission compounds were formaldehyde in asphalt manufacturing, acetaldehyde in the paper manufacturing and textile processing industries, and butyraldehyde in the printing and painting industries. Therefore, to increase the effectiveness of aldehyde reduction, proper control devices need to be installed and operated according to the emission characteristics of aldehydes.

• 한국환경보건학회지
• /
• 제44권2호
• /
• pp.178-187
• /
• 2018

Objectives: This study evaluated the odor emission characteristics from a sewage treatment plant near an industrial complex area in Daegu City. Methods: Odor samples were collected from March 2017 to December 2017 and analyzed for specified offensive odor substances. The odor quotient and the odor contribution were calculated. Results: Ammonia, methyl mercaptane, hydrogen sulfide, dimethyl sulfide, acetaldehyde, propionylaldehyde, toluene, xylene, and methylethylketone were detected in all samples for monitoring the specified odor compounds. The result of contribution analysis is that hydrogen sulfide made the highest contribution in all processes, followed by acetaldehyde. Conclusion: The major components of odor can be determined by evaluating their degree of contribution to the odor intensity and the concentration of the individual odor component. To increase the effectiveness of odor reduction, rather than addressing high-concentration odor compounds, policies focused on materials with a high odor contribution are necessary.

• 한국환경보건학회지
• /
• 제43권4호
• /
• pp.314-323
• /
• 2017

Objectives: This study evaluated the odor emission characteristics from a wastewater treatment plant in an industrial complex area in Daegu City. Methods: Odor samples were collected from March 2016 to December 2016 and were analyzed for specified offensive odor substances. The odor quotient and the odor contribution was calculated. Results: Ammonia, hydrogen sulfide, acetaldehyde, and toluene were detected in all samples for monitoring specified odor compounds. The result of contribution analysis is that hydrogen sulfide had the highest contribution in all processes, followed by acetaldehyde. Conclusion: The major components of odor can be determined by evaluating the degree of contribution to the odor intensity and the concentration of the individual odor component. To increase the effectiveness of odor reduction, rather than addressing high-concentration odor compounds, policies focused on materials with a high odor contribution are necessary.