• 제목/요약/키워드: Semiconductor wastewater

검색결과 39건 처리시간 0.031초

응집제와 관형막을 활용한 CMP 폐수 처리 가능성 연구 (The Feasibility Study of CMP Wastewater Treatment Using Tubular Membrane and Coagulants)

  • 정호찬;정철중;송자연;김연국;이선용
    • 한국물환경학회지
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    • 제28권5호
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    • pp.639-645
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    • 2012
  • The purpose of this study is to identify the possibility of the CMP wastewater treatment from semiconductor fabrication under operating tubular membrane with coagulants. To find suitable coagulants treating CMP wastewater, we conducted Jar-test. After Jar-test experiments suitable coagulants are PAC(17%), $Ca(OH)_2$ and optimum coagulant dosage is PAC(17%) 10mg/L, $Ca(OH)_2$ 110 ~ 120mg/L. Based on these results, the tubular membrane was applied to CMP wastewater, the turbidity removal efficiency is $Ca(OH)_2$ > PAC(17%) > Nothing. The fast cross-flow velocity and backwash process what are operating characteristics of tubular membrane can be stable CMP wastewater treatment. But when the coagulant and tubular membrane are used at the same time, the withdraw and treatment of the CMP wastewater are possibile. However further treatment process needs if treated water will be used for semiconductor fabrications.

진동막분리장치에 의한 반도체폐수처리와 재이용에 관한 연구 (A Study on the Semiconductor Wastewater Treatment and Recycling by VSEP system)

  • 강경환
    • 한국환경과학회지
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    • 제14권3호
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    • pp.335-343
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    • 2005
  • The objective of this research is to evaluate a feasibility of wastewater reuse by membrane treatment with vibrating membrane separation equipment. Molecular weight of compounds in wastewater, permeability of membrane and retentate characterization after membrane filtration were investigated in order to determine appropriate membrane pore size and materials for wastewater treatment. Selected membrane was evaluated with vibration membrane separation equipment to optimize operating conditions. The following conclusion are drawn. 1. We got as following test results after the distribution of particles in the semiconductor wastewater, are made up of $1\~20{\mu}m$. Si, gold and Al in turn are contained in semiconductor wastewater. 2. Recovery rate is changeless under increasing recovery rate in operation. Though a value can be if pressure can be changed, the highest value of permeate rate is presented in 150 psi. 3. The AS-100(polysulpone) was selected as the most appropriate membranes for the treatment of semi-conductor wastewater to VSEP system. The fouling almost did not occur during this experiments. The analyses of treated water with VSEP system showed conductivity: 0.059,us/cm, TDS: 40mg/l, COD: 20mg/l, SS : 5mg/l, n-Hexane: 8.3mg/l. Comparing previous systems, operating expenses is decreased by more $50\%$.

Removal of sulfate ion from semiconductor wastewater by ettringite precipitation

  • Chung, Chong-Min
    • Membrane and Water Treatment
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    • 제13권4호
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    • pp.183-189
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    • 2022
  • This study seeks towards an optimal way to control sulfate ions in semiconductor wastewater effluent with potential eco-toxicity. We developed a system based on ettringite (Ca6Al2(SO4)3(OH)12·26H2O). The basic idea is that the pH of the water is raised to approximately 12 with Ca(OH)2. After, aluminium salt is added, leading to the precipitation of ettringite. Lab-scale batch and continuous experiment results with real semiconductor wastewater demonstrated that 1.5 and 1 of stoichiometric quantities for Ca2+ and A3+ with pH above 12.7 could be considered as the optimal operation condition with 15% of sludge recycle to the influent. A mixed AlCl3 + Fe reagent was selected as the beneficial Al3+ source in ettringite process, which resulted in 80% of sludge volume reduction and improved sludge dewaterability. The results of continuous experiment showed that with precipitation as ettringite, sulfate concentration can be stably reduced to less than 50 mg/L in effluent from the influent 2,050 ± 175 mg/L on average (1,705 ~ 2,633 mg/L).

폐수의 악취측정을 위한 금속산화물 반도체 및 전기화학식 가스센서 어레이 특성 평가 (Evaluation of Metal Oxide Semiconductor and Electrochemical Gas Sensor Array Characterization for Measuring Wastewater Odor)

  • 임봉빈;이석준;김선태
    • 센서학회지
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    • 제24권1호
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    • pp.29-34
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    • 2015
  • This study aimed to evaluate the characterization of a metal oxide semiconductor and electrochemical gas sensor array for measuring wastewater odor. The sensitivity of all gas sensors observed in sampling method by stripping was 6.7 to 20.6 times higher than that by no stripping, except sensor D (electrochemical gas sensor). The average reduction ratio of sensor signal as a function of initial dilution rate of wastewater was in the order of food plant > food waste reutilization facility > plating plant. The sensitivity of gas sensors was dependent on both the type of wastewater and the dilution rate. The sensor signals observed by the gas sensor array were correlated with the dilution factor (OU) calculated by the air dilution sensory test with several wastewater ($r^2=0.920{\sim}0.997$), except the sensor signals of sensor D measured in the plating plant wastewater. It seems likely that the gas sensor array plays a role in the evaluation of odor in wastewater and is useful tool for on-site odor monitoring in the wastewater facilities.

Biodegradation of Hydrogen Peroxide in Semiconductor Industrial Wastewater with Catalase from Micrococcus sp.

  • Oh, Sung-Hoon;Yu, Hee-Jong;Kim, Moo-Sung;So, Sung;Suh, Hyung-Joo
    • Preventive Nutrition and Food Science
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    • 제7권1호
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    • pp.33-36
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    • 2002
  • A catalase from Micrococcus sp. isolated from soil was applied to degrade hydrogen Peroxide in wastewater from a semiconductor industry. The degradation rates of hydrogen peroxide increased with increasing reaction time and catalase concentrations in the reaction mixture. However, in the presence of aluminum chloride or chloride oxide used in detergent compounds, the degradation rate of hydrogen peroxide was not affected. Enzyme stabilizers and antifoam did not affect the degradation rates of hydrogen peroxide.

Struvite 결정화를 이용한 반도체 폐수처리 시 불소제거를 위한 최적 조건 (Optimum Condition for Fluoride Removal Prior to the Application of Struvite Crystallization in Treating Semiconductor Wastewater)

  • 안명기;우귀남;김진형;강민구;류홍덕;이상일
    • 한국물환경학회지
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    • 제25권6호
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    • pp.916-921
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    • 2009
  • This study was aimed to both enhance the fluoride removal and to reduce the phosphorus removal in treating semiconductor wastewater using $Ca(OH)_2$ at low pH so as to facilitate struvite crystallization reaction. The struvite crystallization could be introduced after fluoride removal by retaining the phosphorus source. As the results, the method applied in this study achieved high fluoride removal efficiency (about 91%) with retardation of phosphorus removal at pH 4, compared to conventional methods where the removal of fluoride and phosphorus were done at pH 11. Therefore, the fluoride removal at low pH would contribute to the enhancement of nitrogen and phosphorus removals in a consecutive struvite crystallization reactor. Treatment of semiconductor wastewater at low pH using $Ca(OH)_2$ also had lower (about 20%) water content of precipitated sludge compared to conventional method. As the molar ratio of Ca to F increased the removal efficiencies of fluoride and phosphorus increased. Although the amount of seed dosage didn't affect the removal of fluoride and phosphorus, its increase reduced the water content of precipitated matter. Finally, considering consecutive struvite reaction, the optimum condition for the removal of fluoride and phosphorus was as follow: pH: 4, the molar ratio of Ca:F: 1:1.

Recovery of ultrafine particles from Chemical-Mechanical Polishing wastewater discharged by the semiconductor industry

  • Tu, Chia-Wei;Wen, Shaw-Bing;Dahtong Ray;Shen, Yun-Hwei
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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    • pp.715-718
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    • 2001
  • This study uses traditional alum coagulation and sedimentation process to treat CMP wastewater from cleaning after polishing. The primary goal is to successfully recycle both solid fines and water for semiconductor manufacturing. Results indicated that CMP wastewater may be successfully treated to recover clean water and fine particles by alum coagulation. The optimum operating conditions for coagulation are as fellowing: alum dosage of 10 ppm, pH at 5, rapid mixing speed at 800 rpm, 5 min rapid mixing time, and long slow mixing time. The treated water with low turbidity and an average residual aluminum ion concentration of 0.23 ppm may be considered for reuse. The settled sludge after alum coagulation contains mainly SiO$_2$particle with a minor content of aluminum (1.7 wt%) may be considered as raw materials for glass and ceramic industry.

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반도체 제조공정의 폐수슬러지로 합성된 Hydroxyapatite를 이용한 인산이온의 흡착 (The Adsorption of Phosphate Son Using Hydroxyapatite synthesized by Wastewater Sludge of Semiconductor Fabrication Process)

  • 강전택;정기호;신학기
    • 한국환경과학회지
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    • 제11권3호
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    • pp.257-262
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    • 2002
  • The hydroxyapatite(HAp) for the present study was prepared with the wastewater sludge from semiconductor fabrication process and it was crystallized in an electric furnace for 30 min at 90$0^{\circ}C$. The adsorption characteristics of HAp for phosphate ion in aqueous solution has been investigated. The adsorbed ratio of phosphate ion for HAp were investigated according to the reaction time, amount of HAp, concentration of standard solution, pH of solution, and influence of concomitant ions. The amount of adsorbed phosphate ion decreased with the increase of pH due to the mutual electrostatic repulsion between adsorbed phosphate ions and competitive adsorption between phosphate ion and OH- ion in aqueous solution. The maxium amount of the adsorption equilibrium for phosphate ion was about 24 mg/g of HAp. The HAp would likely to be a possible adsorbent for the removal of phosphate ion in the waste water.

Use of laminar flow water storage tank (LFWS) to mitigate the membrane fouling for reuse of wastewater from wafer processes

  • Sun, Darren Delai;Wu, You
    • Membrane and Water Treatment
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    • 제3권4호
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    • pp.221-230
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    • 2012
  • This study employed the modified fouling index (MFI) to determine the performance of a two-step recycling system - a membrane filtration integrated laminar flow water storage (LFWS) tank followed by an ion exchange process to reclaim ultrapure water (UPW) from the wastewater generated from semiconductor wafer backgrinding and sawing processes. The first step consisted of the utilization of either ultrafiltration (UF) or nanofiltration (NF) membranes to remove solids in the wastewater where the second step consisted of an ion exchanger to further purify the filtrate. The system was able to produce high purity water in a continuous operating mode. However, higher recycling cost could be incurred due to membrane fouling. The feed wastewater used for this study contained high concentration of fine particles with low organic and ionic contents, hence membrane fouling was mainly attributed to particulate deposition and cake formation. Based on the MFI results, a LFWS tank that was equipped with a turbulence reducer with a pair of auto-valves was developed and found effective in minimizing fouling by discharging concentrated wastewater prior to any membrane filtration. By comparing flux behaviors of the improved system with the conventional system, the former maintained a high flux than the latter at the end of the experiment.

한외여과를 이용한 폐 CMP Slurry의 분리에서 압력의 영향 (Pressure Effect on Ultrafiltration of Used CMP Slurry)

  • 홍성호
    • 상하수도학회지
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    • 제18권4호
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    • pp.486-492
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    • 2004
  • CMP (Chemical mechanical polishing) is inevitable process to overcome $0.2{\mu}m$ wire thickness in semiconductor industry. In this study, effect of pressure to separate used CMP slurry into solid and liquid for recycle and reuse by ultrafiltration was investigated. Also, water quality after the ultrafiltration such as turbidity and TDS was evaluated. The material of membrane used in the study was PVDF. The used CMP contained 0.5% of solid content and then concentrated up to 18% by weight. The used CMP can not be concentrated higher than 18% because of viscosity and abrasion of pump. The tested feed pressures were 22.1, 29.4 and 36.8 psi. The results have shown that operating at 36.8 psi has advantages on operation time and total flux. The specific flux showed some variation at 1 to 15 of concentration factor but no difference after 15 of concentration factor. Mass balance of solid at initial stage of the operation showed some unbalance because of deposition of solid on the membrane, which was main reason to reduce flux. Turbidity was very stable at lower than 0.2NTU for 22.1 and 36.8 psi of feed pressure.