• Journal of Animal Environmental Science
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• v.16 no.1
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• pp.51-60
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• 2010

This experiment was conducted to investigate the effects of concentrated pig slurry separated from membrane filter and by environment-friendly agro-materials mixtures on growth of lettuce in hydroponics. The swine waste treatment system having a ultra filtration and a reverse osmosis process was designed in this study. Filtration of pig slurry was necessary to prevent the hose clogging in hydroponics. Primary separation using ultra filter was followed by concentration by RO (Reverse Osmosis). The concentrated pig slurry (CS) was mixed by five different environment-friendly agro-materials mixtures. The chemical nutrient solution was the solution of National Horticulture Research Station for the growth of lettuce. The concentration of nutrient solution in hydroponics was adjusted a range of 1.5 mS/cm in EC. The concentrated pig slurry was low in phosphorus(P), suspended solid and heavy matal, but rich in potassium (K). The concentrated slurry was lowest in the growth characteristics of leaf lettuce. And also SPAD value in leaf was reduced in plot treated with concentrated slurry. But the growth of lettuce in the mixtures plot (CS+BM+AA, CS+BM+AA+SW) in hydroponics was significantly high compared to concentrated slurry. The fresh yield of lettuce was 78, 84% that of nutrient solution as 131.9, 142.2g in plot of CS+BM+AA and CS+BM+AA+SW, respectively. Our studies have shown that it is possible to produce organic culture using concentrated slurry and environment-friendly agro-materials mixture, although growth is slower than when using a conventional inorganic hydroponic solution.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.10
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• pp.684-693
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• 2012

The stormwater runoff from the increasing paved roads and vehicles resulted in the increase in the pollutants load to adjacent water bodies. The granular media filtration facilities are the most widely adopted to minimize the non-point source pollution from motorways. It is essential to consider the severe variation of hydraulic condition, suspended solid (SS) characteristics, and the medium characteristics for stormwater management filter. In this study, different types of media, including sand, were tested and the performance of downflow sand filters was investigated under various linear velocity and influent solid particle size. Results showed that the best medium is the coarse sand with large grain size, which showed the specific SS removal before clogging of more than $8.498kg/m^2$, the SS removal of higher than 95%, and minimum head loss. Linear velocity did not affect the total solid removal, while the performance was improved when fine solid was introduced. It is suggested that the life of a downflow sand filter bed can be extended by deep bed filtration when influent particles are fine. However, the captured particles can be washed out after a long period of operation.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.3
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• pp.23-32
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• 2014

Recently, it is increase in the processing of organic waste using anaerobic digestion. Therefore, the studies on the processing method for increasing the anaerobic digestion waste water. But it is very difficult to solid-liquid separation, because the characteristics of anaerobic digestion waste water. So this study evaluate solid-liquid separation efficiency of anaerobic digestion sludge using CST(Capillary Suction Time), TTF(Time to Filter). To address this problem, a membrane filter press of the lab scale was produced and the anaerobic digestion wastewater was applied to it. Polymer coagulants were found to be most suitable 7192PLUS and 1T60, It is necessary to minimum injection concentration is 7192PLUS (200 mg/L), 1T60 (100 mg/L). To evaluate dehydration efficiency, it was measured the moisture content of the dehydrated cake and suspended solids of decanted water. As a result, showed that a high removal efficiency of 97.4% when the solid-liquid separation using the membrane filter press. And the moisture content of the dehydrated cake was less than 65%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6447-6454
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• 2013

Seawater intake systems have significant problems due to seawater pollution, suspended solids, unstable intake and maintenance etc. An underground type seawater intake system was newly developed to overcome the existing weaknesses and was facilitated in Gyukpo port. In this study, to check the performance of the new system, the samples for water quality and the 3-D numerical modeling test were conducted. The five times test included the COD, total nitrogen, total phosphorus, pH, and suspended solid for the intake system. The analyses show that the COD, total nitrogen, total phosphorus, PH showedminor changes before and after. On the other hand, the change in suspended solids was significant and water was purified below 5 mg/l, first level fisheries water, after. The numerical model adopted the RNG $k-{\epsilon}$ algorithm and the CFX model based on the finite volume method. The porosity algorithm was used to reproduce filtered-sand, outer diameter, and thickness. The numerical results showed that the double pipe is advantageous in that it provides a uniform pressure between the inner and outer pipe for the flow to be stable. In addition, the use of multiple intake pipes did not interfere with the discharge reduction of 0.98 at the both intake pipes compared with the central intake pipe.

• The Korean Journal of Malacology
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• v.18 no.1
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• pp.53-59
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• 2002

The distribution and density of the pen shell, Atrina (Servatrina) pectinata japonica, were investigated to estimate population ecological parameters and biomass. Samples were collected during cruises from April to June 1999 in the coastal waters of Chungchung-namdo, Korea. The oceanographic conditions such as depth, temperature, transparency and suspended solids were measured from sampling stations. Seawater depth ranged from 3.9 m to 75.9 m and the mean was 28.5 m (SE = 0.97). The mean density of the pen shell was higher in the depth of 18.0-30.8 m. The water temperature of the bottom ranged from 7.0-21.5$^{\circ}C$ and the mean was 14.$0^{\circ}C$. The transparency ranged from 1.2-13.5 m and the mean was 4.8 m. The suspended solids ranged from 6.0-93.5 mg/l and the mean was 48.0 mg/l. The sand proportion of the sediment was > 50%. The mean densities of the pen shell by sediment type were 7.3 individuals/40 m$^2$ (SE = 2.16) in the sand, 5.6 individuals/40 m$^2$ (SE = 1.48) in the muddy sand, 3.0 individuals/40 m$^2$(SE = 1.89) in the sandy mud, and none in the mud. The sandy bottom, accounting for 29.8% of the overall habitat area, had a maximum density of 7.3 individuals/40 m$^2$.

• Korean Journal of Ecology and Environment
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• v.44 no.4
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• pp.373-384
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• 2011

The objective of this was to determine how the seasonal intensive rainfall influenced the water quality, and to analyze the long-term temporal trend of water chemistry and spatial heterogeneity in the upstream watershed of Southern Han River using water quality dataset from 1997 to 2007. The largest seasonal variability in most parameters occurred during the two month July and August and there were closely associated with a large spate of summer monsoon rain. Total phosphorus (TP), chemical oxygen demand (COD), and suspended solids (SS) were greater during summer than any other seasons, and had a direct correlation with precipitation (r>0.4, p<0.01, n-120). In addition, dissolved oxygen (DO) had and inverse function with precipitation (r=-0.542, p<0.01). Overall, the data of total phosphorus (TP) and suspended solids (SS) showed that water quality was worst in Site I1, compared to the others. This was due to continuous effluents from the highlands' fields and cattle farms within the upstream area of Doam lake (Song stream). Based on the overall dataset, an efficient water quality management is required in the highlands and farms areas for better water quality with precipitation (r.0.4, p<0.01, n=120).

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.790-795
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• 1995

Flocculant-producing microorganisms were isolated from soil samples using kaoline as the flocculating test material. One strain that had high flocculating activity among them was selected and identified as Arcuadendron sp. TS-49. The favorable medium for production of the flocculant was 3% glucose, 0.2% yeast extract, 0.1% $NH_4Cl$, 0.01% $MgSO_4$, and 0.05% $MnSO_4$ in 150ml of T.W. with initial pH 7.0.The optimum culture temperature and pH were $30^{\circ}C$ and pH 7.0, respectively. The flocculant activity was observed most highly after 4 to 5 days of cultivation at the optimum condition and decreased significantly with the lapse of cultivation time. The flocculant was produced constituently and seemed to be degraded for ressimilation during cultivation. The productivity achieved by this system was about ten-fold higher than that of scrrening mediuim. This bioflocculant flocculated all tested solids, including various microorganisms and organic/inorganic compounds. Several qualitative analyses of the bioflocculant showed that it was a kind of glycoprotein containing sugars and protein.

• Environmental Engineering Research
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• v.23 no.2
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• pp.210-215
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• 2018

Coal seam gas (CSG) water, to be discharged, has been usually treated in reverse osmosis (RO) plants which require extensive and expensive pre-treatment. However, current low gas prices have been a great driver for relevant industries to seek for alternative cost-effective technologies in the aspect of its beneficial use and fit-for-purpose usable water production. In this paper, a combined system with a two-stage pore control fiber (PCF) filtration and a RO system was designed and tested for CSG water treatment. Also, a coagulation reactor was placed in front of the PCF to further enhance suspended solid removal. More than 99% of SS were removed through the PCF filtration while organic, total nitrogen and total phosphorous were mostly removed by the RO system. Especially along with a decrease in conductivity, the total dissolved solid derived from salts was mainly removed in the RO system. Having $OH^-$ undetected, $HCO_3{^-}$ was found to be a dominant compound and its removal efficiency was 97-98% after the RO treatment. And a Fe(III) type of Polytetsu, which was the first to be tested in this paper, was found to be a better option than a Al(III) type of Poly Aluminium Chloride due to its greater coagulation efficiency and applicability at a broader range of pH than the Al(III) type. In addition, there was no noticeable change in oxidation reduction potential, suggesting that an additional process is required to oxidize non-ionic organic carbons (detected as total organic carbon).

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.138-138
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• 2000

국내의 백상지 공정은 공정에 투입되는 청수의 양을 줄이면서 동시에 폐수 배출 양을 감 소시키기 위해 많은 노력을 하고 있다. 공정으로 유입되는 청수의 양과 처리된 폐수의 양을 줄이기 위한 방법으로 PDFCpolydisk filter)를 도입하여 백수를 여과하여 showertf sealing 에 재사용하고 있으며 공정수 재활용에 따른 유기 물질과 무기물질의 계 내로의 축적을 방 지하기 위한 효과적인 폐수 처리방법을 모색하고 있다. 일반적으로 청수를 백수로 대체할 경우 공정 백수 내에 TDSCtotal dissolved solid), T TSSCtotal suspended solid), CODCchemical oxygen demand), 전기 전도도와 칼숨 경 도 등이 증가되며 음이온성 저해 물질Canionic trash)이 증가하여 보류 및 지력증강용 첨가제의 효율 을 떨어뜨릴 뿐만 아니라 마모, 슬라엄, 펠트 막힘 등의 문제를 유발하게 된다고 알려져 있다. 청수를 백수로 대체함에 따라 생기는 이러한 문제를 해결하면서 효율적인 청수 절약 방안 을 세우기 위해서는 무엇보다도 문제를 유발하는 원인 물질의 축적 양을 예측하는 것이 중 요하다고 판단된다. 본 연구는 백상지 공정의 폐쇄화 수준이 높아짐에 따른 공정 백수 내의 유기물질의 축적 현상을 분석하는 것올 목적으로 하였다. 이를 위해 산화전분을 유기물질의 대표하는 물질로 설정하였다. 이는 백상파지와 함께 초지계 내로 유업되는 산화전분은 파지의 4%를 차지할 정도로 유입량이 많을 뿐만 아니라 음이온성을 띄고 있어서 지료에 홉착율이 낮고 양이온성 고분자의 효율을 저해하며 슬라임의 원인이 되기도 하는 물질이기 때문이다. 산화전분의 축적 현상을 분석하기 위하여 pilot 설비 상세 설계도를 참고하여 하루 생산량 이 16 T/D이고 백상파지만이 파지로 유입되는 백상지 생산 공정을 모델로하였으며, 산화전 분의 홉착과 용출 모델을 만들어 상용 시율레이터를 이용하여 시율레이션 프로그램을 작성 하였다. 시률레이션 프로그램에서는 장섬유 미세섬유, 충전제를 지료 구성 성분으로 설정하였고 O Orccotoma 등이 사용한 일과 보류도 모델을 응용하여 보류도 모델올 만들었다. 산화전분은 백상파지에 포함된 형태로만 초지계 내로 유입되며 백상파지가 해리되는 과정에서 완전히 백수에 용출되었다가 지료 구성 성분에 홉착되는 것으로 가정하였다. 지료 홉착된 산화전분 의 양은 용존 산화전분 총량에 비례하는 것으로 가정하였으며, 이 때 이 비례상수를 전분 홉착율이라 정의하였다. 시율레이션 결과, 공정 폐쇄화가 진행됨에 따라 백수 내의 산화 전분 농도는 증가하게 되 며, 폐쇄화 수준이 높아질수록 백수 내 전분 농도의 증가량은 더 높아졌다. 백수 내의 전분 농도의 증가량은 백상파지 첨가량이 증가할수록, 표면 사이징 양이 증가할수록 커졌다.

• Journal of Wetlands Research
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• v.18 no.3
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• pp.244-249
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• 2016

Anaerobic digester supernatant including high concentrations of nitrogen is recycled to water treatment line and make pollutant load increase in municipal wastewater treatment plant(MWTP). To treat nitrogen in anaerobic digester supernatant is suggested the method of MWTP retrofit. In this study, the lab scale reactor was operated about 200 days using supernatant of anaerobic digester. The results could draw operation condition that ammonium nitrogen removal efficiency more than 90% and nitrite conversion efficiency over 70%. Correlation between operation efficiency and operation factors was analyzed based on the operation results. Ammonium nitrogen remove efficiency and nitrite conversion efficiency were related to solid retention time (SRT), ammonium nitrogen load and ammonium nitrogen loading per unit mixed liquer suspended solid (MLSS). Results of this study can be used effective data on nitritation of supernatant of anaerobic digester, and be expected to increase availability of nitritation.