• Journal of Environmental Science International
• /
• v.1 no.2
• /
• pp.93.1-104
• /
• 1992

Because of varied functions and characteristics, water soluble polymers have lone attracted much intrest in both academic and industrial fields, especially now in pollution problems such as wastewater treatment through ployrneric flocculants. In this regard, the main objective of this study is to synthesize polymeric floccuants containning hydrophobic group in presence of the potassium persulfate/sodium thiosulfate redox system and to estimate their flocculating ability on the kaolin suspension. In order to test the flocculating power of flocculant prepared on the kaolin suspension system, turbidity of the supernatant liquid, residence time, filtration rate of flocculated samples, have additionally been measured from the flocculation experiments and analysed In comparision with the theoretical background.

• Proceedings of the Korean Environmental Sciences Society Conference
• /
• 1997.10a
• /
• pp.71-75
• /
• 1997

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.14 no.3
• /
• pp.192-200
• /
• 2002

There is a volume change between the sediments and the dredged materials because the dredged materials is fully disturbed by the dredger and settled in the basin from the stabilized condition. The volume of the dredged materials is also affected by the coagulants and flocculants (hereafter C & F) which was used to speed up the settling of the suspended solids. In this study, the volume change of the dredged materials is analysed in detail due to the injection amount of the C & F. The dredged materials were sampled in the lagoon located in the East coastal zone, and the volume change of the samples is quantitatively analysed by the laboratory test due to the change of the clay content and the amount of the C & F. The optimal amounts of the C & F is determined by showing the minimal volume change due to C & F injection. From the experimental results, the volume of the dredged materials is increased 1.68 times on an average and the volume change rate is slightly increased, i.e., negligible, as the clay content increase in the case of the C & F injection.

• Journal of Environmental Health Sciences
• /
• v.35 no.5
• /
• pp.411-416
• /
• 2009

This study was initiated to improve the cooling water quality by chemical coagulation and sedimentation in steel mills. Due to the inefficient flocculation in the settling tanks of blast furnace cooling water systems, the solid particles in the cooling water overflow accumulate and clog the cooling system. To protect the cooling water system from such fouling, proper flocculants must be continuously used. Laboratory tests were performed for the indirect cooling water system of a plate mill. The batch test in the gas scrubbing cooling water system of a blast furnace showed that the proposed coagulant was more effective for the improvement of coagulation and sedimentation than the existing one. During the tests, cationic flocculants were more effective than use of only an anionic flocculant. The suggested combination of anionic and cationic flocculants can probably improve the turbidity removal efficiency of the cooling water. Proper control of the overflow rate by the designed residence time would help turbidity removal efficiency in the settling tank. In addition, the settling can be enhanced by adopting rapid and slow mixing alternatively. Scale problems in blast furnace cooling water system were reduced to some extent by efficient settling.

• Applied Chemistry for Engineering
• /
• v.9 no.7
• /
• pp.1043-1046
• /
• 1998

Aluminium based inorganic flocculants are extensively used in this country in the removal of fine particles present in the raw water for the production of drinking water. These inorganic flocculants, however, have potential hazard of high residual aluminium ions in the treated waters, which is known to be one of the reasons of alzheimer's disease. Inorganic flocculants alone are sometimes incapable of treating water when there are excessive turbidity in the raw water sources due to flooding. A polyamine type polymeric flocculant has long been used to treat raw water in the drinking water production in the European countries and United State of America. The optimum reaction conditions such as mole ratio of epichlorohydrin(EPI) to dimethylamine(DMA), reaction temperature and time for each stage for the pilot scale preparation of polyamine from EPI-DMA was studied in this work. The variation of intrinsic viscosity and flocculating efficiency in the water treatment of the synthesized polyamines were evaluated. The residual materials after polymerization reaction were analyzed by gas chromatography to study the effect of variation of reaction conditions.

• Applied Chemistry for Engineering
• /
• v.9 no.3
• /
• pp.451-456
• /
• 1998

By grafting acrylic acid, fumalic acid and maleic acid onto chitosan, graft copolymers, CsAa, CsFa and CsMa, respectively were prepared for potential uses as flocculants in waste water treatment. When 40 ppm of each grafted chitosan sample was added into the waste water, CsMa showed the best removal rate of COD and suspended solids(SS), followed by CsFa and CsAa and chitosan. The transmittance and removal rate of COD and SS were the highest at pH 5. All grafted chitosan exhibited better performance than chitosan itself, resulting from the amphiphilic property of grafted chitosan copolymer with carboxy groups.

• Journal of Industrial Technology
• /
• v.7
• /
• pp.27-47
• /
• 1987

Fine anthracite is very difficult to upgrade by conventional processes such as gravity concentration or froth flotation, because large quantities of fine coals are generated at the mining and preparation stages and a significant portion of these fine coals are mixed with gangue minerals. This study, therefore, was carried out for the purpose of improving recovery of low ash clean coal, effective beneficiation of low-grade coking coal and removal of sulphur from high-sulphur coals by employing the method of selective agglomeration using oil or polystrene flocculants, for coals which are generally hydrophobic in nature will be extracted by using flocculants. Studies were performed by varying solid concentration, concetration of bridging liquid, mixing speed and mixing time, balling speed and balling time, dispersant dosage, flocculant dosage, pulp pH, and particle size. The results were : when the methods of the oil agglomeration and selective flocculation were employ(in the two process the sample was ground to the size of -74 micron), 1) ash content of the agglomerated coal was 9.85, 7.83%, 2) combustibel recovery of it was 98.5%, 93.5%, respectively. It was observed in selective flocculation that polystyrene is an effective flocculant for coal, De-entrapment of shale from the concentrate flocculated by mechanical agitation was necessary for substantional reductions in final ash content.

• Environmental Engineering Research
• /
• v.9 no.2
• /
• pp.58-65
• /
• 2004

• Journal of Energy Engineering
• /
• v.10 no.2
• /
• pp.114-119
• /
• 2001

TRIGA Mark-II&III 연구로서의 운영과정에서 발생된 방사성 슬러리 함유 폐액에 대하여 음이온, 앙이온, 그리고 비이온 응집제를 첨가하였을 때의 여과 효과를 실험실 규모의 진공여과 장치로 연구하였다. 여과 실험 자료를 이용하여 Darcy’s Law에서 유도된 여과 케익 저항 값을 산출하였다. 응집제 사용으로 응집제를 사용하지 않은 경우롸 비교하여 케익 저항값의 개선은 있었지만, 수분함량은 증가하였다. 각각의 응집제 사용에 따른 침전율, 여과 케익의 수분함량, 그리고 여과 케익 저항 값을 비교한 결과 음이온 응집제 12~16ppm/$\ell$ waste를 사용하였을 경우가 가장 효과적인 것으로 나타났다.

• Resources Recycling
• /
• v.25 no.3
• /
• pp.3-10
• /
• 2016

The passive treatment was required a large area for the treatment of acid mine drainage (AMD), and pollutants were discharged with mine drainage by the increased flow rate in summer. This study was performed to improve the turbidity and to precipitate the pollutants quickly using coagulants and flocculants in AMD of abandoned mine sites that were difficult to build the passive treatment system. The coagulant PAC (Poly aluminium chloride) and flocculant PAM (Polyacrylamide) were selected to improve turbidity in W mine waters. We also tested the particle size analysis, ICP-OES and/or SEM-EDS for water and sludge samples.