In order to evaluate the fundamental properties of sewerage pipes for ductile properties and allowable deflection ratios, A field tests were conducted on the glass fiber reinforced plastic pipe. Also, Allowable deformation test was carried out to determine the soil-pipe relationship and earth pressure due to the loading of dump truck.

본 연구는 하수처리수의 농업용수 재이용에 따른 벼의 미질특성을 파악하기 위하여 시험포장을 조성 하여 쌀의 아밀로스 및 단백질 함량, 완전미 도정수율을 분석하고 유의성을 고찰하였다. 시험포장의 수 질 및 토양환경을 조사하였으며, 근적외선 분광분석법을 통해 미질 특성을 분석하였다. 하수처리수로 재 배된 쌀의 미질 특성치는 일반미와 큰 차이가 나지 않는 것으로 나타났으며, 통계분석 결과 5% 유의수 준에서 각 처리구별 유의차가 있는 것으로 나타났다.

Most wastewater treatment plants are facing odor and sludge disposal problems. In this lab-scale study, odor and sludge from wastewater treatment processes were treated using a combined non-thermal plasma and sludge reactor. The hydrogen sulfide concentration introduced to the reactor was varied at 10, 20, and 50 ppm, and its removal efficiency and system performance were determined. Ozone was produced by the plasma reaction at a concentration of 200 ppm under the given condition. 80% of the hydrogen sulfide was removed regardless of its introduced concentration. In addition, due to the ozone carried over to the sludge reactor, the organic constituents in the waste sludge in terms of TCOD decreased by 30%. The ion concentrations of HS- and SO₄²⁻ in the sludge increased during the four hour experimental period. As a result, the plasma oxidation system can treat waste sludge effectively for the simultaneous reduction of sludge volume and odor.

본 연구는 최종 해양에 배출되는 하수슬러지에 함유된 오염물질의 농도와 분포특성을 파악하고자 하였다. 연구에 사용된 시료는 하수 슬러지 발생업체의 최종 저장조에서 20점을 채취하였고 시료의 조제를 비롯하여 최종 기기분석까지 해양환경공정시험기준을 적용하였으며, 다 환방향족탄화수소류(PAHs)는 U.S EPA 기준에 맞춰 16종을 분석하였다. 분석결과 중금속인 비소는 최대 15.29 ㎍/g, 카드뮴 2.04 ㎍/g, 크롬 632.98 ㎍/g, 구리 2,388.28 ㎍/g, 납 77.71 ㎍/g, 아연 2,928.28 ㎍/g이었고, 폴리염화비페닐(PCBs) 7종 중 최대값은 0.80 ng/g이고 7종의 합은 ND ～ 2.50 ng/g으로 나타났다. 다환방향족탄화수소류(PAHs)의 각 항목별 최대값은 나프탈렌 1,199.5 ng/g, 아세나프틸렌 35.48 ng/g, 아세나 프텐 104.94 ng/g, 플루오렌 424.86 ng/g, 페난트렌 606.91 ng/g, 안트라센 121.96 ng/g, 플루오란텐 683.64 ng/g, 피렌 1045.70 ng/g, 벤죠(a)안트 라센 270.49 ng/g, 크리센 288.76 ng/g, 벤죠(b)플루오란텐 175.81 ng/g, 벤죠(k)플루오란텐 162.22 ng/g, 벤죠(a)피렌 185.84 ng/g, 인데노 (1,2,3-cd)피렌 136.22 ng/g, 디벤즈(a,h)안트라센 21.60 ng/g, 벤죠(g,h,i)페릴렌 320.00 ng/g으로 나타났다. 한편 분석시료 20점 중 해양배출처리 기준 제1기준을 초과한 시료는 구리 1점이었고, 생물독성시험이 필요한 제2기준을 초과한 시료는 크롬 1점, 구리 10점, 아연 2점, 나프탈렌 3점 으로 나타났다.

H₂S adsorption characteristics of adsorbent made by sewage sludge were investigated. The manufacturing method of adsorbent used in this experiment is to mix sewage sludge, waste lime, the high-alumina cement, NaHCO₃, and activated carbon. For analyses of the manufactured adsorbent, various methods such as scanning electron microscope (SEM), measurements of BET surface area and pore volume were adopted. As operating variables, adsorption temperature (25~45 ℃), H₂S concentration (2.48~31.62 ㎎/L) and the kinds of adsorbent were applied. As major adsorption characteristics, adsorption rate and adsorption equilibrium capacity were measured by using batch type experimental apparatus. The experimental result showed that the BET surface area of the calcinated sewage sludge was 83.3 ㎡/g, which indicates 4 times higher than that of non calcination and the BET surface area of adsorbent made by sewage sludge mixing with various by-products ranged over 265 to 286 ㎡/g. It was also found that the H₂S adsorption equilibrium capacity of adsorbent made by sewage sludge decreases with increasing temperature, but increases with increasing H₂S concentration. Through the evaluation of adsorption isotherm model, it was found that H₂S adsorption isotherm for adsorbent made by sewage sludge can be expressed well by Langmuir and Freundlich isotherm equation.

In this study, we attempted to analyze removal efficiency of odorous compounds emitted from Grit chamber and night soil treatment facility using biofilter with microbial catalyst. Air dilution method was used for mixed odor gases analysis. UV-vis spectrophotometer for ammonia and Hydrogen sulfide, Methyl mercaptan, Dimethyl sulfide, Dimethyl disulfide were measured using GC/PFPD. Sample gases were collected at the inlet and outlet of biofilter. The analysis result showed that average concentration of major odorous compounds were ammonia with 5,100 ppb and hydrogen sulfide with 797 ppb from grit chamber and ammonia with 1,407 ppb and hydrogen sulfide with 2,475 ppb from night soil treatment facility. Hydrogen sulfide was the most influential compound of malodor based on odor quotient index. The average dilution threshold of odor was 923 at grit-chamber and 1,267 at night soil treatment facility. The removal efficiency of odorous compounds from sewage treatment facility were more than 94% using polyurethane foam biofilter within empty bed contact time 3sec. The emitted concentration to the atmosphere was satisfied with the criterion of the offensive odor control law.

This study is to evaluate control effects of separation wall by surveying water quality and sewer overflows during dry and wet periods in combined sewer and separated sewer systems. Ravine water from the combined Seokgyo outfall with the separation wall was separated about four times larger than sewage flow during dry periods. The water quality of the combined Seokgyo outfall with separation wall during dry periods is flow weighed average T-N 22mg/L, T-P 2.4mg/L, the combined Chenseokgyo outfall without the separation wall is average T-N 21mg/L, T-P 2.6mg/L, and the separated Pyoungsong center outfall is average T-N 12mg/L, T-P 1.0mg/L. The T-N, T-P concentration in separated outfall make form about 44%, 42% of the combined outfall, and this means the separated outfall (i.e. storm sewer) is polluted by inflow of sewage. The overflow load of the separated outfall is ten times higher than the combined outfall and its overflow load per rainfall is three times than combined outfall during the wet periods. Therefore, the control plan of overflow load is required in storm sewer. The control effects of the overflow load increased 100% by setting the separation wall in the combined sewer, and showed 44% increase without the separation wall in separated sewer, but forecasted over than 82% increase of effects with the separation wall.

  In this paper, we propose sludge collection strategies which allocate each sewage store of village to sewage treatment plants and decide the schedule of sludge collection in order to collect sludge efficiently. The strategies aim to decrease transportat

This study presented the plan for treatment plant as investigating the technical examination of existing landfill leachate treatment plant at Geumgo-Dong and the plan of landfill leachate treatment with sewage treatment. The R/O process in 1st stage landfill leachate treatment plant(plant capacity:150m3/d) was closed in consideration of economical aspect and efficiency. It is to be desired that the 1st stage and 2nd stage landfill leachate treatment (plant capacity: 250m3/d) are combined, and are converted the Pretreatment process with nitrogen treatment process, and after total landfill treatment leachate happened from landfill site is pretreated it is transferred the sewage treatment plant. Ammonia nitrogen load of landfill leachate that was transferredthe sewage treatment plant(plant capacity: 300,000m3/d). This load is no problem at now, but it is need change the inflow line for sewage treatment plant and the enlargement of pretreatment process in case that the raw landfill leachate is increased.

The characteristics of odor and VOCs emitted from a sewage treatment plant was investigated to provide the basic informations in the design of odor and VOCs treatment processes. The sewage treatment plant which treated domestic wastewater only and consisted of a flow equalization tank, thicker, and sludge container was selected. Odor and VOCs sampled three times (June - July) at the temperatures ranging from 24℃ to 27℃ were analyzed by GC/MS and GC/FPD. Odors were hydrogen sulfide, dimethylsulfide, ammonia, and styrene. Among them, the main compounds were dimethyldisulfide (14.45~2,340.91 O.U.) and ammonia (18.51~16,520 O.U.). The order of odor dilution ratio and odor unit can be listed as follows : Sludge container ＞ Flow equalization tank ＞ Thicker. The main VOC produced from sewage treatment plant was benzenes, and the others were dichloromethane, toluene, ethylbenzene, m,p-xylene, styrene, 1,2,4,-trimethylbenzene, 1,3-dichlorobenzene, and 1,2-dichlorobenzene. The concentration of toluene of a flow equalization tank, thicker, and sludge container were produced from 70.38 ppb to 103.07 ppb, from 28.18 ppb to 40.35 ppb, and from 67.92 ppb to 180.26 ppb. The producing order of VOC can be listed as follows : Sludge container ＞ Flow equalization tank ＞ Thicker.

본 연구는 2002년 1월부터 2003년 5월까지 오염원이 비교적 단순한 산지하천에서의 무기 영양염 및 유기물 변동을 고찰하기 위해 낙동강 지류인 대천천의 상류에서 실시되었다. 조사지점은 인위적인 오염이 없는 DC1, 주위의 식당과 민가에서 생활하수가 유입되는 DC2, DC3, DC4그리고 부분적으로 수질이 자연 정화된 DC5이다. 전기전도도, 탁도, BOD는 하수의 유입으로 인하여 DC2에서 급격히 증가하였다가 DC5에서 다시 낮아졌다. 수층의 NH

The sewer systems of cities are considered an odor source. Especially, the public do not want a wastewater treatment plant (WWTP) near their properties due to the emission of odor emanating from such sources, although they play an important role in urban development. Therefore, a number of researchers have tried to characterize sewer and WWTP odors and reduce their emissions. However, the majority of the odor research performed in Korea has focused mainly on the measurement of the sensory odor intensity and the 12 odorants defined in the Korean Odor Prevention Law. Only a few studies have been performed on identifying the mechanisms of odor generation from sewer and WWTPs. Without the correct knowledge of the odor generation mechanism of sewer systems, it is impossible to develop an appropriate odor control scheme. Therefore in this paper, the literature relating to research on the odors emitted from sewers and WWTPs has been reviewed. The information provided in this paper will be useful to other researchers interested in the emission of odors from sewer systems.

This study examined management problems about the current rural sewage treatment facilities where is outside of sewage treatment boundary in Chungnam province. It suggested that optimum plan based on this investigation as follows. Management cost of sewage treatment facilities considering the circuit operation person was charge of about 51.8% personnel expenditure, 31.0% electricity power cost, and 9.9% repairing expenses. So, the presumptive cost will be to ￦191/㎥․d for the facility capacity a year. Recently the core operation and management has converted to environment related section or consignment company but a work subjective section administers the facilities that is a 75 districts of total 161 business zone yet. It is desirable to conclude a commission contract with the company which is operate the facilities including circuit operation person for sewage treatment plants. And it recommend that one who has qualified or certificate requirement for the sewage treatment should be stationed at the related section because there are no experienced men in many treatment facilities. Rural sewage treatment facilities and small sewage treatment plant whose capacity is more than 500㎥/d ought to be controlled by collecting sewage tax involved the related special budget according to local government regulations and the charge would be to notify the actual usage. Also, it is necessary to introduce unmanned automatic operating system in order to reduce labor costs, advance progressive management, and operate integrated management of facilities.