• Journal of Korean Society on Water Environment
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• v.27 no.6
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• pp.932-937
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• 2011

Main objectives of this paper were; firstly, to explain impacts of suspended solid in the water body on the relationship between water quantity and water quality; secondly, study on the inter-relationship between organic materials, nutrients, pathogens, and suspended solids considering eco-friendly water resources. Relationship between water quality and water quantity is not easy to understand as it includes physicochemical-biological reactions and diffuse pollutions. Especially, suspended solid makes water resource management difficult. Eroded soil in the upper land transported to the downstream by water flows carrying biological and physicochemical information and sedimented in the downstream. As sediment scoured under high flow condition and environmental change, suspended solid and sediment should be emphasized for understanding the inter-relationship between water quality and water quantity. Knowledge gaps between known monitored data and management of suspended solid were identified as well for future study.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.6
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• pp.39-48
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• 2010

Sediment yields from Imha watershed were simulated during 1993-2008 using Hydrologic Simulation Program-Fortran (HSPF). Using observed daily stream flow for 2004-2008 and hourly suspended solid concentration for three events during 2006, HSPF was calibrated and validated at the sites of Imha and Youngyang for stream flow and Dongchun and Jangpachun for sediment yield. The calibration and validation results represented high model efficiency for simulating daily stream flow and hourly suspended solid. The determination coefficients of calibration and validation were 0.90 and 0.81 for daily stream flow, and 0.91 and 0.86 for monthly stream flow, respectively. Based on model tolerances for calibration and validation of stream flow, HSPF performance for simulating stream flow represented 'very good'. The determination coefficients of calibration and validation were 0.94-0.96 and 0.95 for hourly sediment yields, respectively. The average yearly sediment yield during 1993-2008 was 122,290 ton/year and most of sediment yield (77 % of total yield) were generated from June to August. The calibrated HSPF simulated well the movement of water and eroded soil within Imha watershed.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.109-115
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• 2014

The purpose of this study is to estimate the sediment volume concentration of the liquified-solid mixture which is included fine sediment fractions, according to the variance of the channel slope and the water supply. The numerical model was performed by using the Finite Differential Element Method (FDM) based on the equation for the mass conservation, momentum conservation and the equation of coarse sediment an fine sediment. In comparison of varying the channel slope, the deeper the channel slope, the inflection point of the sediment concentration was occurred rapidly. In comparison of variance of the water supply, as the water supply increases fluctuation with high sediment concentration. In this situation, debris flow changes to the turbulent flow and the sediment becomes to be floated. In comparison varying the length paved saturated sediment, the longer the length, the high concentration of sediment occurred, for the safety of the slope it is needed to check the possibility of the erosion in the slope by debris flow. The results of this study will provide useful information in predicting of the disaster by the liquified-solid mixture and in prevention of the debris flow with various the slope in the mountain side.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.334-342
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• 2012

To know the role of 'the solid compressive pressure to the first solid layer of a cake, $p_d$' in the 'unified theory on solid-liquid separation', we analyzed extremely compressible cake formed with floc for the following three operations with our new concepts. First, the role of $p_d$ was studied in calculating the sediment thickness of floc, and in calculating the cake thickness in cake filtration performed with floc sediment. Second, we calculated the expression procedure using $p_d$. Finally, the influence of $p_d$ on cake thickness in hindered sedimentation, and on the calculation of the procedure of hindered sedimentation $p_d$ was verified. Thus the possibility of application of 'unified theory on solid-liquid separation' and the importance of $p_d$ was verified. Through these processes, new theoretical definitions of the cake filtration, expression and hindered sedimentation was established.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.6
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• pp.742-747
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• 2004

Solid-liquid separation of swine wastewater was conducted using bentonite as coagulant. During the separation experiment, coagulation efficiency was also investigated. To determine optimal bentonite dose, 0.1, 0.2, 0.4, 0.8, and 1.6% (w/v basis) of bentonite was dosed. Suspended solid removal efficiency was 87-98% at whole bentonite dosage. But sediment volume was increased, and settling velocity was decreased at excessive bentonite dosage. Therefore optimal bentonite dosage was evaluated around 0.2-0.4%. In the test to determine optimal pH, coagulation using bentonite was performed at pH 3, 4, 5, 6, and 7. At lower pH suspended solid removal efficiency was increased. However, sediment volume was also increased and phosphorus release was observed. Thereby optimal pH for bentonite coagulation might be appeared in the range of 6-7.

• Journal of Environmental Science International
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• v.24 no.12
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• pp.1617-1627
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• 2015

This study was carried out to investigate the characteristics of suspended solid concentration in small forest watershed, Hwacheon, Gangwondo. For five rainfall events from July 2013 to August 2013, rainfall, discharge, and suspended solid load has been measured. The results showed that the fist flush effect was observed for suspended solid in each rainfall event, sediment rating curve was obtained with $y=30.029x^{1.573}$ at rising limb and $y=12.902x^{1.8827}$ at falling limb, and EMC (event mean concentration) of suspended solid was calculated to 9.4 mg/L. EMC was compared to the values from the watershed that has various land use types and EMC from forest watershed was much lower that from the crop, paddy or low covered forest watershed.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.975-982
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• 2009

The purpose of this study is to offer informations about the current conditions and basic data of stream sediments in Busan city. So we first select 14 urban streams and collect sediment samples. Then, COD, proximate analysis, volatile solid, organic carbon content and elemental analysis were conducted to determine characteristics of the sediments. Results show that COD, volatile solid, Organic carbon content, T-N of sediment are determined in the range of 1.20~75.07 mg/g, 0.19~11.54%, 0.23~34.21% and 0.76~3.46%, respectively. Analysis data of sediments were compared with USEPA sediment quality standards and ontario sediment quality guidelines. As a result, when compared with COD, volatile solid and organic carbon content values, Bosucheon and Gudeokcheon are relatively heavily contaminated than the remainder sampling sites. But when compared with T-N values, all of sites were evaluated as seriously contaminated. Finally, for the determination of the correlations between sediment COD and moisture contents, ash contents, volatile solid, total organic carbon, total nitrogen and total carbon, linear model was fitted to the data using a least-squares algorithm. As a result, Linear model was well fitted to each data with good values of the correlation coefficient (r=0.9664~0.8501).

• Journal of Korea Water Resources Association
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• v.39 no.5 s.166
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• pp.405-415
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• 2006

The deposition of sewer solids during dry weather in combined sewer systems results in a loss of flow capacity that may restrict flow and cause a local flooding and enhanced solids deposition. Sewer solid accumulations in drainage systems also create the 'first-flush' phenomena during wet weather runoff periods. In order to solve these problems, measurement of these loadings for a given sewer system for extended period is needed but this task is very difficult and extremely expensive. In this study, generalized procedures for estimating sewer sediment solid during dry weather in combined sewer systems developed by the U. S. Environmental Protection Agency were applied in a drainage system in Korea. As result, the appropriate equation can be selected and applied according to the available data. However, the estimated solid sediment shows considerable difference between methods which classified by model and estimation methods of variable. The estimated values using equations (1) $\sim$ (4) are greater than that of equations (5) $\sim$ (9) and intermediate models show greater values than elaborate or simplest models. The comparison between simulated and measured solid deposition is difficult due to the absent of measurement data, but this estimation method can be used usefully for the management of sewer solid with reduction of cost and effort if the measurement is carried out and the equation is adjusted according to the actual drainage systems in Korea.

• Journal of Environmental Science International
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• v.11 no.8
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• pp.793-800
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• 2002

Butyltin (BT) compounds were measured in seawater, sediment, sediment core, settling solids, and plankton from Gwangyang Bay in 2001, Tributyltin (TBT) was detected in seawater from 1 out of the 7 seawater sampling sites and in sediment from 18 out of the 35 sediment sampling sites. The highest concentration of TBT was found in the sediment from the site near Yeosu Harbor (53 ng Sn/g dry wt), acting as the point source for TBT The mean concentrations of TBT were in the order of plankton> settling solids> sediment. The degradation indexes ([DBT]+[MBT]/[TBT]) for the plankton were less than 1, indicating the possibility of recent inputs of TBT. The indexes for the sediment and settling solids ranged from 1.14 to 8.73. The composition of the BT compounds found in the settling solids was similar to that found in the sediment. The vertical profile of the total BT compounds in the sediment was characterized by an abrupt decline from the surface. However, no butyltin compounds appeared below a depth of 10 cm, corresponding to the 1980s. Accordingly, the current results demonstrated that the levels of all butyltin species in the environment of Gwangyang Bay were relatively lower than those in other polluted coastal areas. The vertical profile also suggested a fairly recent history for the down-core.

• Journal of the Korean GEO-environmental Society
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• v.11 no.1
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• pp.35-43
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• 2010

The main purpose of this study is to offer informations about the current conditions and basic data of sediments for the urban streams in the Busan city. Total 14 urban streams were selected and sediment samples were collected. Then, It was investigated the sediment qualities though the measurement of pH, proximate analysis, elemental analysis, COD, organic carbon content, volatile solid content and heavy metal concentration. Results show that COD, organic carbon content, volatile solid content and heavy metal concentration of sediment are determined in the range of $1.20{\sim}75.07mg\;L^{-1}$, 0.19~11.54%, 0.23~34.21% and $0.4{\sim}732.6mg\;kg^{-1}$, respectively. Finally, Analysis data of sediments were compared with USEPA sediment quality standards and ontario sediment quality guidelines. As a result, when compared with USEPA sediment quality standards, total 9 samples were evaluated as heavily polluted and total 3 samples were evaluated as moderately polluted. But, when compared with ontario sediment quality guidelines, total 3 samples were evaluated as Severe effect level and total 10 samples were evaluated as lowest effect level.