• Title/Summary/Keyword: 강제 환기 시스템

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Evaluation of Air Quality in the Compost Pilot Plant with Livestock Manure by Operation Types (축분 퇴비화시스템 운용방식에 따른 실내 대기오염 평가)

  • Kim, K.Y.;Choi, H.L.;Ko, H.J.;Kim, C.N.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.283-294
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    • 2004
  • Air quality in the livestock waste compost pilot plant at the Colligate Livestock Station was assessed to quantity the emissions of aerial contaminants and evaluate the degree of correlation between them for different operation strategies; with the ventilation types and agitation of compost pile, in this study. The parameters analyzed to reflect the level of air quality in the livestock waste compost pilot plant were the gaseous contaminants; ammonia, hydrogen sulfide, and odor concentration, the particulate contaminants; inhalable dust and respirable dust, and the biological contaminants; total airborne bacteria and fungi. The mean concentrations of ammonia, hydrogen sulfide, and odor concentration in the compost pilot plant without agitation were 2.45ppm, 19.96ppb, and 15.8 when it was naturally ventilated, and 7.61ppm, 31.36ppb, and 30.2 when mechanically ventilated. Those with agitation were 5.50ppm, 14.69ppb, and 46.4 when naturally ventilated, and 30.12ppm, 39.91ppb, and 205.5 when mechanically ventilated. The mean concentrations of inhalable and respirable dust in the compost pilot plant without agitation were 368.6${\mu}g$/$m^3$ and 96.0${\mu}g$/$m^3$ with natural ventilation, and 283.9${\mu}g$/$m^3$ and 119.5${\mu}g$/$m^3$ with mechanical ventilation. They were also observed with agitation to 208.7${\mu}g$/$m^3$ and 139.8${\mu}g$/$m^3$ with natural ventilation, and 209.2${\mu}g$/$m^3$ and 131.7${\mu}g$/$m^3$ with mechanical ventilation. Averaged concentrations of total airborne bacteria and fungi in the compost pilot plant without agitation were observed to 28,673cfu/$m^3$ and 22,507cfu/$m^3$ with natural ventilation, and 7,462cfu/$m^3$ and 3,228cfu/$m^3$ with mechanical ventilation. They were also observed with agitation to 19,592cfu/$m^3$ and 26,376cfu/$m^3$ with the natural ventilation, and 18,645cfu/$m^3$ and 24,581cfu/$m^3$ with the mechanical ventilation. It showed that the emission rates of gaseous pollutants, such as ammonia, hydrogen sulfide, and odor concentration, in the compost pilot plant operated with the mechanical ventilation and with the agitation of compost pile were higher than those with the natural ventilation and without the agitation. While the concentrations of inhalable dust and total airborne bacteria in the compost pilot plant with the natural ventilation and with the agitation, the concentrations of respirable dust and total airborne fungi in the compost pilot plant with the mechanical ventilation and agitation were higher than those with the natural ventilation and without the agitation of compost pile. It was statistically proved that indoor temperature and relative humidity affected the release of particulates and biological pollutants, and ammonia and hydrogen sulfide were believed primary malodorous compounds emitted from the compost pilot plant.

Preestimate Airflow in Greenhouse by CFD Simulation Method (CFD 시뮬레이션 기법에 의한 온실내 공기유동 예측)

  • 윤남규;김문기
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1999.11a
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    • pp.118-121
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    • 1999
  • 환기는 온실내 미기상에 중요한 영향을 미치는 물리적 과정임에도 불구하고 이에 대한 연구는 아직까지 빈약해 왔다. 환기는 온실내의 온도, 습도 그리고 이산화탄소 등의 가스농도를 최적으로 제어하기 위한 수단으로 사용되어진다(Bailey, 1988). 강제환기시스템은 대부분의 온실에서 그 사용이 보편화되지 못하였으므로, 일반적으로 자연환기가 원예시설의 공기교환을 위한 유일한 수단이 되고 있다. (중략)

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Identification of pathogen and actual culture state of king oyster mushroom (Pleurotus eryngii) (큰느타리버섯 주요재배시 실태조사 및 병원균 분리동정)

  • Ha, Tai-Moon;Chi, Jeong-Hyun;Ju, Young-Cheuol;Sung, Jae-Mo
    • Journal of Mushroom
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    • v.4 no.4
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    • pp.135-143
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    • 2006
  • We have investigated cultural circumstance and given condition of king oyster mushroom(Pleurotus eryngii) growing farmer. We collected many pathogens from King oyster mushroom growing farmer and identified with chemicobiological test and microscope. Most of investigated farmers neglected their's growing room cleaning and washing, after harvesting At pin-heading induction time, humidity degree in growing room was kept of high level and Air ventilation volume was so little that fruit-body formation ratio was low. The collected pathogens were twenty eight strains and identified with Pseudomonas sp., Trichoderma sp. mostly. During the spawn running time and pin-heading induction time, contamination by Trichoderma sp. occurred mostly, but during the fruit-body growing time, contamination by Pseudomonas sp., Erwinia sp. etc, occurred.

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A Study on the Long-term Operating plan of Ventilation System of Apartment House in terms of Energy Performance (공동주택 강제 환기 시스템의 건물에너지 측면에서의 장기적 운영 방안에 관한 연구)

  • Kim, Seung-Chul;Yoon, Jong-Ho;Baek, Nam-Choon;Shin, U-Cheul
    • 한국태양에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.115-123
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    • 2011
  • Because buildings recently built have been highly insulated and highly airtight, it is impossible to emit toxic substances from interior finishing materials only by natural ventilation. Therefore, they cause indoor air pollution and it may threaten the user"s health such as atopic dermatitis, bronchial asthma and (allergic) rhinitis. Domestically, users spend indoors 80 percent of their time of a day. With the increased interest in indoor air quality, the introduction of forced ventilation system for new-built apartment buildings has been legislated. However, toxic substances from indoor are mostly below there commended standard approximately 23 months later. Thus, this study has assumed the status of the apartment buildings 23 months later through a simulation, regarded $CO_2$ as an exclusive indoor air pollution source. In the process of effectively eliminating the $CO_2$, this study has also been conducted on an operating plan that can provide superior performance from the energy side.

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The Performance Evaluation of the Exhaust Stack used in High Riser Public House (초고층 공동주택 국소배기용 입상덕트의 배기성능평가)

  • Kwon, Yong-Il;Kim, Ung-Yong;Shin, Hyun-Gon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.22 no.3
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    • pp.60-67
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    • 2014
  • Exhaust system used in toilet and cooking place of high riser public house is roof fan of two basic types : natural roof ventilator and natural/forced roof ventilator. Natural/forced roof ventilator has a motor in the rotary shaft. There are many high riser public house in Korea. These buildings were not viewed as being major contributors to exhaust pollutants producted in indoor. It was because many engineers thought that exhaust in high riser building depend on stack effect. This study investigates on stack pressure determined by exterior pressure and the difference pressure control in exhaust stack used in high riser public house. This paper focuses mainly on the effect of the time interval for power supply of motor installed in roof fan with function of natural wind velocity and of exhaust air volume of toilet. It is observed there are higher exhaust efficiency than the existing natural roof ventilator.

A study on the availability of ATS system in speed augmentation (속도 향상시의 ATS 시스템 가용성 연구)

  • Kim, Yong-Kyu;Baek, Jong-Hyun
    • Proceedings of the KIEE Conference
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    • 2004.04a
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    • pp.238-240
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    • 2004
  • 현재 우리나라에서 사용 중인 신호시스템은 지상신호 방식인 자동폐색장치(ABS)를 사용한다 이는 선로를 패색구간으로 배분한 후, 각각의 패색 구간에 설치된 신호기에 의해 열차의 이동을 실행한다 이러한 신호체계에 문제점이 발생할 경우, 기관사에게 주의를 환기시켜 강제적으로 열차를 정지시키는 역할을 하는 자동열차정지장치(ATS)가 1969년부터 도입, 사용 중에 있다. 본 논문에서는 ATS 시스템의 고속, 고밀도 운전 적용 가능성 및 차상신호방식 사용시의 ATS 적용 가능성에 대해 분석한다.

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The Effects of Winch-curtain Ventilation on the Indoor Environment of a Fattening Swine House (윈치커튼 환기가 비육돈사의 실내 환경에 미치는 영향)

  • Kim, Hyeon-Tae;Song, Jun-Ik;Choi, Hong-Lim
    • Journal of Animal Environmental Science
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    • v.18 no.1
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    • pp.1-8
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    • 2012
  • The study was conducted to investigate the effects of climate on indoor environment of a swine house with natural. This study was tested in the beef swine stall at Young-in, Kyung-ki do. The test was experimented for the effect of interior environment by the outdoor environment and the interior-pan. The results are as follows. 1. In test 1 ($T_{out}$ : $25.7^{\circ}C$, without fan), an indoor air flow pattern was showed that entered from sidewall winch-curtain to went out of a indoor by the ridge winch-curtain. And the velocity of a section of the center was measured two times as large as the velocity of the floor. It is the acceleration of the velocity by thermal buoyancy. And, the entered air was rapidly dissipated by flow energy. So that in the swain livestock with sidewall winch-curtain is effected by thermal buoyancy. And the air temperature of the indoor was distributed more higher as compared with the outdoor temperature. This result is caused by the sensible heat from swine and the ventilation is restricted. 2. In test 2 (($T_{out}$ : $25.7^{\circ}C$, with fan), the velocity of a section of the center was measured more higher as compared with the test 1. And the variance of air velocity was distributed higher as compared with the test 1. This result is showed dead region of air flow with a fan operation. And, the variance of gas density was distributed lower as compared with the test 1.

A Study on the Performance of Ondol with a Ventilation System (환기시스템을 갖춘 온돌 성능에 관한 연구)

  • Jeon, Sung-Taek;Cho, Jin-Pyo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.7
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    • pp.4047-4051
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    • 2014
  • Modern apartment houses are constructed to be relatively airtight with a high heat insulation system to increase the energy efficiency. Such a system has a range of deleterious effects due to the insufficient ventilation. In this study, the ondol system, which is used as a heat source typical of winter in Korea, was set as the default system to evaluate the indoor heat environment according to the ventilation method, the factors of energy reduction by the ventilation system was analyzed. The experimental apparatus was used to simulate the ambient conditions for a certain constant temperature and humidity chamber. The experimental results showed that the supply water temperature higher air volume decreases with increasing supply air temperature in the following order: floor supply/exhaust > total heat exchange supply/exhaust > forced supply/exhaust. Through this study, the applicability of various ventilations could be examined.

Validation of FDS for Predicting the Fire Characteristics in the Multi-Compartments of Nuclear Power Plant (Part I: Over-ventilated Fire Condition) (원자력발전소의 다중 구획에서 화재특성 예측을 위한 FDS 검증 (Part I: 과환기화재 조건))

  • Mun, Sun-Yeo;Hwang, Cheol-Hong;Park, Jong Seok;Do, Kyusik
    • Fire Science and Engineering
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    • v.27 no.2
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    • pp.31-39
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    • 2013
  • The Fire Dynamics Simulator (FDS) has been applied to simulate a full-scale pool fire in well-confined and mechanically ventilated multi-compartments representative of nuclear power plant. The predictive performance of FDS was evaluated through a comparison of the numerical data with experimental data obtained by the OECD/NEA PRISME project. To identify clearly the FDS results regarding to the user-dependence in the process of FDS implementation except for the intrinsic limitation of FDS such as simple combustion model, only the over-ventilated fire condition was chosen. In particular, the importance of accurate boundary conditions (B.C.) in mechanically ventilated system were discussed in details. It was known from FDS results that the B.C. on inlet and outlet vents did significantly affect the thermal and chemical characteristics inside the compartments. Finally, it was confirmed that the FDS imposed an accurate ventilation B.C. provided qualitatively good agreement with temperatures, heat fluxes and concentrations measured inside the nuclear-type multi-compartments.

The Diffusion Behavier Analysis Caused by High Pressure Natural Gas Leak in Enclosure with and without Ventilation System (I) (밀폐공간 및 강제환기공간에의 천연가스 고압분출 시 농도 확산분포 거동해석 (I))

  • Ha, Tae-Woong;Ha, Jong-Man;Kim, Eun-Ja
    • Journal of the Korean Institute of Gas
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    • v.16 no.4
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    • pp.23-31
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    • 2012
  • The basic understanding of gas diffusion and technology to predict the diffusion phenomena are needed to prepare against a disaster of leakage of natural gas and to design better consistent and reliable gas supply system in enclosure. The experimental results of British Gas Technology Co. are used in present study as a reference of theoretical study using CFD. The present results of 2D CFD analysis for mass flow rate of nozzle release show good agreement with experimental results within 2.6 % error. 3D CFD analysis for the characteristics of natural gas diffusion in enclosure with various ventilation patterns also gives reasonable agreement with experimental results.