• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.154-159
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• 1992

An investigation was carried out to study the feasibility of tofu preparation with using isolated soyprotein(ISP) only. The ISP tofu was prepared by boiling the ISP suspension for 2 min before addition of coagulants. Effects of coagulants($CaSO_{4},\;CaCl_{2}\;MgCl_{2}\;GDL$) and coagulation temperature in the range of $2{\sim}95^{\circ}C$ were studied on the amounts of coagulants required, size and shape of coagulates, volume yield and textural properties of tofu. It was found that amounts of coagulants and tofu volume was significantly reduced and the larger and cloud-like shape was obtained as the coagulation temperature increased. A rather precipitation was occured under $40\;or\;50^{\circ}C$, which caused difficulty for tofu formation by pressing. GDL and $CaSO_{4}$ showed higher yields than those of $CaCl_{2}\;and\;MgCl_{2}$ at low temperature range and little difference at high temperature. In the textural properties of hardness, brittleness and gumminess of tofu were almost lineary and rapidly increased as the coagulation temperature increased where $CaCl_{2}\;and\;GDL$ produced highest and lowest of those values, respectively. The elasticity was reduced as the temperature increased for those made with $MaCl_{2},\;CaSO_{4}\;GDL\;and\;CaCl_{2}$, tofu showed little change.

• Applied Biological Chemistry
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• v.47 no.3
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• pp.370-372
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• 2004

• Journal of Korean Society of Water and Wastewater
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• v.31 no.2
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• pp.125-139
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• 2017

In this paper, the performance of a synthetic fiber filter aimed at high-speed operation and dosed with different coagulants or filter aids was investigated. Without a coagulant, the filter efficiency was about 62% which was greatly enhanced when three types of coagulants namely PAC, Alum, and $FeCl_3$ were used. Among the coagulants tested, PAC was the most effective, giving 91% filter efficiency, followed by Alum with 90%, and $FeCl_3$ with 78%. PAC worked effectively at a very small range of dose, but Alum was relatively effective in a wide range of concentration. Compared with PAC and Alum, $FeCl_3$ provided more or less contant efficiency regardless of its dose but gave the poorest filter efficiency. Moreover, as the inflow turbidity increased, headloss increased and the efficiency decreased at any dose and type of coagulant. The headloss recorded in this particular synthetic fiber filter is not significant as compared to that observed in typical granular filters. The recovery of solids estimated after filter cleaning was about 80% for both PAC and Alum, but poorer at 72% in the case of $FeCl_3$ due to the heavy and large floc characteristics. The recurrence of filter efficiency verified through repetitive filter runs was found to be satisfactory.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.4
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• pp.169-176
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• 2016

This research explored the feasibility of preparing and utilizing preformed polymeric solution of Fe(III) as coagulants for water treatment. The differentiation and quantification of hydrolytic Fe(III) species in coagulant was done by utilizing spectrophotometric method based on the interaction of Fe(III) with Ferron as a complexing agent. The properties of the synthesized polymeric iron chloride (PICl) showed that the quantity of polymeric Fe(III) produced at r = 1.5 was 20% of the total iron in solution, as showing maximum contents. Coagulation experiments were conducted under the condition of various coagulant doses and pH for each coagulant prepared. From the comparison of the characterization of coagulation for $FeCl_3$ (r = 0.0) and PICl (r = 0.5, 1.0, 1.5) coagulants, PICl (r = 0.5, 1.0, 1.5) coagulants was found to be more effective than other coagulant for the removal of organic matters. The experimental results for the coagulation tests at various pH ranges showed that the PICl was least affected by the coagulation pH and PICl was very effective for the removal of turbidity and organic materials over wide pH range (pH 4-9) tested.

• Journal of the Korean Home Economics Association
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• v.17 no.1
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• pp.12-19
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• 1979

Five kinds of soybean curd were propared with five coagulants, such as, calcium sulfate, calcium chloride, magnesium chloride, glucono delta lactone and acetic acid. The products were evaluated by the sensory and objective examination. Optimal concentrations of each coagulant were determined. Soybean curd preparation was also standardized. The textural characteristics of the five soybean curds which were made by the standard recipe were measured by a Texturometer and a Penetrometer. The results were as follows : 1. From the proliminary study, the optimal concentration of coagulants for the soybean curd preparation, as determined by the sensory evaluation was 1.84% of calcium sulfute, 1.05% of calcium chloride. 1.84% of calcium sulfute, 1.05% of calcium chloride. 1.84% of magnesium chloride, 1.97% of glucono delta lactone and 0.48% 11of acetic acid. 2. As the result of the sensory evaluation, the most acceptable soybean curd was determined to be one with acetic acid. Next, in order of accetability , were magnesium chloride, calcium chloride, glucono delta lactone, calcium sulfate soybean curds and commerical soybean curd. 3. Through the objective examination of the five soybean curds by a Texturometer and a Penetrometer, it was found out that, calcium sulfate soybean curd was the hardest and the hardness decreased in order of glucono delta lactone, magnesium chloride, calcium chloride, and acetic acid soybean curd. Acetic acid soybean curd, the most acceptable , was 0.47 TU ; and calcium sulfate soybean curd, the least acceptable, was 1.73 TU.

• Journal of Environmental Science International
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• v.8 no.3
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• pp.393-397
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• 1999

Among various reactions which metal sulfides can undergo in the reducing environment, the lattice exchange reaction was examined in a attempt to selectively remove heavy metal ions contained in the Fe-Coagulants acid solution. We have examined Zeta potential along with pHs to investigate surface characteristics of ${FeS}_{(s)}$. As a result of this experiment, zero point charge(ZPC) of FeS is pH 7 and zeta potential which resulted from solid solution reaction between Pb(II) and ${FeS}_{(s)}$ is similar to that of ${PbS}_{(s)}$. Solubility characteristics of ${FeS}_{(s)}$ is appeared to that dissolved Fe(II) concentration increased in less than pH 4, and also increased with increasing heavy metal concentration. Various heavy metal ions(Pb(II), Cu(II), Zn(II)) contained in Fe-coagulants acid solution were removed selectively more than ninety-five percent in the rang of pH 2.5~10 by ${FeS}_{(s)}$. From the above experiments, therefore, We could know that the products of reaction between heavy metal ions and $FeS_{(S)}$ are mental sulfide such as $PbS_{(S)}$, $CuS_{(S)}$ and $ZnS_{(S)}$.

• Analytical Science and Technology
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• v.12 no.6
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• pp.478-483
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• 1999

Coagulation efficiencies of some organic compounds by aluminum based coagulants including alum, PAC, PACS were studied. The coagulation efficiency was highest at the neutral pH. It was decreased with an order of PACS, PAC, and alum at the neutral pH. The organic compounds of high molecular weights showed good coagulation efficiencies with all coagulants, while the small molecules were not coagulated. Organic compounds having more than two adjacent functional groups of OH and COOH showed coagulation efficiencies of 10~80%.

• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.34-39
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• 2009

This study was carried out in order to investigate the decolorization and reduced sludge of real textile wastewater by coagulation process. The aim of the study was to verify the relation between decolorization and coagulants of real textile wastewater treatment processes. Coagulation processes were performed using $FeCl_3$, $FeSO_4$, and $Al_2(SO_4)_3$. Real textile wastewater has a mean concentration for BOD, COD, pH, color to be 800 mg/L, 600 mg/L, 9.7, and 102, respectively. From the experimental results, it was shown that the $FeCl_3$ exhibited higher decolorization at the operating conditions 335~2000 mg/L of coagulants and 500 mg/L NaOH dosage. The efficiency of color removal depended on the wastewater pH and concentration of coagulants.

• Proceedings of the Korean Sanitation Conference
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• 2004.11a
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• pp.54-65
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• 2004

Use of aluminum salts as coagulants In water treatment may lead to increased concentrations of aluminum in finished water. Aluminum is a suspected causative agent of neurological disorders such as Alzheimer's disease. The objective of this study was to examine variation and minimizing in residual aluminum concentration during water treatment process. The aluminum sources at Bokjeong Water Plant were present naturally aluminum in the raw water and derived due to use of PACS as a coagulant. Much of the raw water total aluminum were in particulate and suspended aluminum. In this study was compared the optimize condition to minimize the concentration of residual aluminum using Jar-test with the various coagulants such as alum, PAC, PACS. The results indicated that PACS was more effective than alum, PAC and insufficient or excessive alum, PAC, PACS addition led to increase residual aluminum. Adjustment raw water pH $6.5\~7.0$ before coagulation using PACS was capable of minimizing total and dissolved aluminum. Thus it is important that the optimal dosage of coagulant and the optimal pH adjustment before coagulation can decided to minimize the concentration of residual aluminum in treated water.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.6
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• pp.663-671
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• 2016

Coagulation/precipitation process has been widely used for the removal of phosphate within domestic wastewater. Although Fe and Al are typical coagulants used for phosphate removal, these have some shortages such as color problem and low sedimentation velocity. In this study, both Fe and Al were used to overcome the shortages caused by using single one, and anionic polymer coagulant was additionally used to enhance sedimentation velocity of the precipitate formed. Batch experiments using a jar test were conducted with real wastewater, which was an effluent of the second sedimentation tank in domestic wastewater treatment plant. Response Surface Methodology was used to examine the responsibility of each parameter on phosphate removal as well as to optimize the dosage of the three coagulants. Economic analysis was also done on the basis of selling prices of the coagulants in the field. Phosphate removal efficiency of Fe(III) was 30% higher than those of Fe(II). Considering chemical price, optimum dosage for achieving residual phosphate concentration below 0.2 mg/L were determined to be 18.14 mg/L of Fe(III), 2.60 mg/L of Al, and 1.64 mg/L of polymer coagulant.