Wastewater from the textile industry: Review of the technologies for wastewater treatment and reuse

Ahsan Ali,Jamil Farrukh,Rashad Moeen Ali,Hussain Murid,Inayat Abrar,Akhter Parveen,Al-Muhtaseb Ala’a H.,Lin Kun-Yi Andrew,박영권 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.9

The textile industry is water intensive and discharges numerous coloring compounds into the water body that depend on the industry’s geographical location, the wet processes used for manufacturing, processing conditions, and the substrates involved. Textile wastewater contains chlorobenzenes, phthalates, heavy metals, azo dyes, and chlorophenols that have severe health issues, such as being allergenic, cytotoxic, genotoxic, mutagenic, and carcinogenic threats to living organisms. The differing concentrations of sulfates, chlorides, TOC, TDS, TSS, BOD, COD, high pH, and dye content characterize textile wastewater. To protect the environment and public health, a higher concentration of these items in textile wastewater is needed to treat the textile wastewater effluent before discharge. The conventional treatment methods are not able to fully remove the pollutants, such as physical treatments can only remove grease, oil, and TSS, whereas biological wastewater treatment (aerobic and anaerobic) can only decrease colors, COD, BOD, oil, and phenol with a higher accomplishment period and by-products. Therefore, it is necessary to develop effective ecofriendly, cost-effective, novel techniques, such as membrane technology, and a promising method with fewer by-products. The activated carbon method effectively removes heavy metals and dyes from the textile wastewater, and advanced oxidation processes (AOPs) are a recent development in textile wastewater treatment processes. Combining AOPs methods has been proven effective in removing pollutants when combined with biological and advanced physical processes. This paper reviews the textile manufacturing process, textile wastewater characteristics, textile wastewater’s impact on the environment and health, and the available textile wastewater treatment approach.

간접방류 산업폐수 관리 개선방안 연구

조을생,김병로,김영민 한국환경연구원 2012 수시연구보고서 Vol.2012 No.-

1. 연구의 배경 및 목적 국민의 환경 의식 수준 향상 및 음용수의 안정성 확보, 수생태계 건강성 보호요구가 증가하고 있으며 4대강사업과 관련하여 수계 영향력이 큰 산업폐수에 의한 수질오염 예방 필요성이 증대되고 있다. 그러나 공공하·폐수종말처리시설로 유입하여 연계 처리(간접방류)하는 산업폐수 배출사업장의 경우 직접방류하는 업체에 비해 배출허용기준이 상대적으로 낮고, TMS 부착, 생태 독성 등의 규제가 면제되고 있다. 이에 따라 보다 강화된 배출허용기준이 적용되는 공공수역으로 직접방류하기 보다는 규제 회피를 위한 간접방류로 인해 공공하·폐수종말처리장 과다 유입으로 운영의 애로가 제기되고 있다. 더욱이, 간접방류 배출업소는 폐수를 법적 기준 이하로 전처리하여 공공하·폐수종말처리시설로 유입하여야 하나 전처리의 배출 실태가 불명확하며 이에 대한 관리가 제대로 이루어지지 않고 있는 실정이다. 특히, 공공하·폐수종말처리시설은 법적 방류수 수질 기준 항목인 유기물질 및 영양염류 처리위주로 설계되어, 간접방류 업체에서 특정수질유해물질을 적정 처리하지 않을 경우 미처리된 유해물질은 그대로 수계로 배출되는 실정이다. 따라서 본 연구에서는 간접방류하는 폐수 배출업소들의 폐수 배출 현황 및 특성, 관리체계 검토 등을 통해 산업폐수 관리 선진화에 효과적으로 부응하기 위한 간접방류 산업폐수 관리체계 개선 방안을 도출하고자 한다. 2. 간접방류 폐수배출시설 특성 간접방류 폐수배출시설의 일반 현황을 살펴보면 2010년 기준 간접방류 산업폐수의 방류량은 전체 산업폐수 방류량의 54%를 차지하여 직접방류 산업폐수 방류량보다 많은 것으로 조사되었다. 간접방류 업종별로는 전체 업체 수의 1%인 1종과 2%인 2종 업종이 전체 방류량의 56%와 19%로 총 75%를 차지하며, 전체 업체수의 가장 많은 비중(84%)을 차지하고 있는 5종 업종은 전체 방류량의 7%로 나타났다. 지역별로는 간접방류 업체의 대부분은 ‘나’지역(79%)에 분포하는 것으로 나타났으며 지역별 간접방류 폐수 방류량 분포는 청정지역에서만 1~5종 모두 비슷한 비중을 차지하였고, 나머지 3개 지역은 1종의 방류량이 가장 높은 것으로 조사되었다. 간접방류 폐수배출시설의 폐수 주요 수질오염물질을 분석한 결과 일반오염물질(BOD, COD, SS, TN, TP)이 주요 폐수 성상으로 분석된 업종은 1차 전지 및 축전지 제조시설, 가죽·모피가공 및 제품 제조시설, 고무 및 플라스틱 제품 제조시설, 금속가공제품 제조시설, 출판·인쇄·사진처리 및 기록매체 복제시설, 펄프·종이 및 종이제품 제조시설 등 39개 업종이다. 중금속 및 기타 오염물질이 폐수의 주요 성상으로 분석된 업종은 1차 철강 제조시설, 가죽·모피 가공 및 제품 제조시설, 금속가공제품 제조시설, 도금시설, 반도체, 병원시설, 섬유염색 및 가공시설 등을 포함하여 13개 업종으로 분석되었다. 업종별 처리 후 배출허용기준치를 초과하는 간접방류 업체는 2,557개소이며 이중 87%는 5종이며 초과 업체 대부분이 ‘나’지역에 속한다. 초과 업체의 방류량을 기준으로 보면 초과 업체 수가 29개소인 1종이 163,914톤/일로 초과 업체 전체 방류량의 64%를 차지하며 초과 업체 수 39개소인 2종이 36,536톤/일로 전체 방류량의 14%를 차지하고 있다. 지역별로는 ‘나’지역에 속한 초과 업체의 방류량이 가장 높은 것으로 분석되었다. 또한 수질오염물질 항목별 처리 후 배출허용기준 초과업체를 살펴본 결과 초과 업체의 90%가 일반오염물질을 초과한 것으로 조사되었다. 유기물질 및 영양염류 초과 주요 업종은 기타 식품 제조시설, 기타 기초유기화합물 제조시설, 기타 섬유제품 제조시설, 펄프·종이 및 종이제품 제조시설 등을 포함하여 22개 업종으로 분석되었다. 이 중 기타 식품 제조시설, 조미료 및 식품첨가물 제조시설은 BOD, COD, SS, TN, TP 5종 모두 초과 주요 업종으로 분석되었다. 또한 일반오염물질 초과 업종 중 방류량이 가장 많은 1종 및 2종을 대상으로 4대강34개 중점관리 유역에 속하는 업종을 분석한 결과 반도체 및 전자부품 제조시설(1종 1개소, 2종 2개소), 펄프·종이 및 종이제품 제조시설(1종 1개소, 2종 1개소), 섬유염색 및 가공시설(2종 6개소), 도금시설(2종 1개소), 수도사업시설(2종 1개소), 비알콜성 음료 및 얼음제조시설(2종 1개소), 유리 및 유리제품 제조시설(1종 1개소)로 15개 업체로 나타났다. 중금속 및 기타 오염물질별 처리 후 수질 배출허용기준 초과 업체는 n헥산(광유류) 배출허용기준을 초과한 1종 1개소, 2종 2개소를 제외하고 모두 3∽5종에 해당하는 것으로 나타났다. 그러나 업종별 주요 폐수 성상이 중금속 및 기타 오염물질인 1종 및 2종을 대상으로 처리 후 농도 기입현황을 조사한 결과 농도 기입율이 매우 저조해 데이터 부족으로 배출허용기준 초과 여부를 명확하게 파악할 수 없는 실정으로 이들 업종에 대한 보다 체계적인 모니터링이 필요하다. 본 연구에서는 1종 및 2종을 대상으로 직접방류에만 적용되는 생태독성관리 대상 폐수배출시설 중 4대강 34개 유역에 속하는 간접방류 폐수배출시설을 분석해 본 결과 16개 업종으로 총 163개 업체가 포함된 것으로 생태독성관리 적용이 면제되고 있어 이들에 대한 오염원 관리가 명확하지 않은 실정이다. 3. 정책 제언 간접방류 폐수배출시설의 보다 과학적이고 체계적인 관리를 위해 산업폐수 특성, 업종, 지역(중점관리지역)을 고려하여 선택적으로 수질TMS 부착 및 생태독성관리 제도 적용의 필요 및 적용 대상 업종(안)을 제안하였다. 1) 간접방류 폐수배출시설의 수질TMS 부착 및 선택적 대상시설 일반수질오염물질이 폐수의 주요 수질오염 물질로 분석된 업종이면서 배출허용기준 또한 초과한 22개의 폐수배출시설에 대한 관리 강화가 필요할 것으로 사료된다. 이들 업종 중 2010년 기준 1종 및 2종에 속하는 업종은 섬유염색 및 가공시설을 포함하여 15업종 44개(1종 17개소, 2종 27개소) 업체가 있는 것으로 조사되었다. 특히 펄프·종이 및 종이제품 제조시설 2개소, 섬유염색 및 가공시설 6개소, 도금시설 1개소는 4대강 34개 유역에 속하는 것으로 조사되어 우선 적용 대상이 될 수 있을 것이다. 2) 간접방류 폐수배출시설의 생태독성관리 및 선택적 대상시설 우리나라의 경우에는 직접방류 업체에만 생태독성관리를 적용하고 있으며 간접방류 업체는 생태독성 적용 제외 대상으로 최종 처리장인 공공하·폐수종말처리장에서의 생태독성의 오염원 발생지 관리에 현실적으로 어려움이 있다. 따라서 중금속 등 유해물질이 주요 수질오염물질인 폐수배출시설의 경우에는 간접방류를 할지라도 방류량이 많은 1종 및 2종 업종에는 생태독성관리제도의 적용을 검토할 필요성이 있다. 다만 간접방류임을 감안하여 오염도가 높고 대규모 상수원이 있는 4대강 34개 중점관리유역에 우선 적용하여 성과 및 실적을 토대로 확대 방안을 고려하는 것이 적정할 것으로 판단된다. 다만 본 연구는 「전국 오염원 조사」 자료에 한하여 가이드라인을 제안한 것으로 주요 업종에 대한 현장의 지속적인 모니터링 및 평가를 우선 수행한 결과를 토대로 엄격한 관리가 요구되는 4대강 34개 중점관리 유역부터 단계적으로 적용하는 방안이 바람직할 것이다. 또한 수질TMS 부착의 경우 수질TMS 설치 및 운영비용의 사업자 자가 부담에 따른 경제적 부담 가중으로 인해 정상적인 유지관리의 어려움이 꾸준히 제기되고 있는 점을 고려하여 재정적 지원 방안 마련에 대한 검토도 필요할 것이다. 3) 공공하수처리장의 역할 강화 산업폐수를 유입 처리하는 공공하수처리장의 법적 권한과 책임을 부여하여 유입되는 간접방류 업체 폐수 모니터링에 대한 공공하수처리장의 책임의식 강화가 요구된다. 4) 산업폐수 국가 DB 구축 아울러 산업폐수가 수계에 미치는 영향력이 크다 할 수 있으나 공신력 있는 국가통계자료는 「수질 및 수생태계 보전에 관한 법률」 제23조에 의거하여 매년 조사되고 있는 전국오염원 조사 자료가 거의 유일한 것으로 공개된 데이터가 제한적이다. 따라서 보다 정확한 통계분석이 가능한 데이터 확보 및 국가 DB 구축이 시급하다. 이는 변화하는 산업폐수 배출 실정에 보다 선진적인 관리를 위해서 업종별, 지역별, 폐수 처리기술별 특성이 반영된 차등화된 폐수관리체계 구축을 위해서도 반드시 필요한 기초 자료이다. 1. The Background and Purpose of the Study Public awareness of the environment has been raised and the requirements for securing the stability of drinking water and protecting the health of the aquatic ecosystem have been increasing. And related to the Four Major Rivers Restoration Project, a need to prevent water pollution caused by industrial wastewater, which has a great influence on water systems, is increasing. Meanwhile, in the case of factories that discharge their industrial wastewater to the public wastewater and sewage treatment facilities to treat it, that is to say, indirectly discharge, compared to the factories that directly discharge, a relatively low allowable discharge standard is applied, and they are exempted from the regulations such as TMS attachment and ecotoxicology. Consequently, they mostly discharge indirectly to avoid regulations rather than directly discharge to public waters in which tighter allowable standards for discharge are applied. Such an excessive inflow into the public sewage and wastewater treatment facilities causes difficulties in the operation. Furthermore, although the indirect discharge factory should pretreat its wastewater under the legal standard and then outflow it to the public sewage and wastewater treatment facilities, it is unclear if they discharge pretreated wastewater or not, and even its control is not well conducted. In particular, since the public sewage and wastewater treatment facilities were designed to treat organic matter and nutritive salts, which are included in the legal water quality standard items, if the factory doesn't treat for specific substances harmful to the quality of water appropriately, the untreated harmful substances are discharged to the water system as they are. This study tries to draw a method of improving the management system for indirectly discharged industrial wastewater so as to effectively meet advancements in industrial wastewater management, through a review of the wastewater discharge status and characteristics of the wastewater indirect discharge facilities and the management system. 2. Characteristics of the wastewater indirect discharge facilities A survey on the general status of the wastewater indirect discharge facilities showed that indirectly discharged industrial wastewater outflow formed 54% of the whole industrial wastewater discharge flow in 2010, which means the indirect outflow was higher than the direct outflow. Indirect discharge by classification of industry showed that the industry type 1, which occupies 1% of the entire industries, and the industry type 2, occupying 2% of the entire industries, formed 56% and 19%, respectively, that is a total of 75% of the whole discharge flow, and type 5 which has the largest portion, accounting 84%, of the entire industries formed 7% of the whole discharge flow. According to the regional groups, most of the indirect discharge facilities are located at B (나) zone which account for 79% of the total industries. According to the distribution of the indirect discharge flow by the regional groups, type 1~5 showed similar discharge flow respectively in the clean zone, and at the remaining three zones, the discharge flow of type 1 was the greatest. As a result of analyzing main water pollutants of wastewater from the indirect wastewater discharge facilities, the type of industries in which general pollutants(BOD, COD, SS, TN, TP) are classified as the main wastewater composition included 39 categories of industry such as the primary battery and storage battery manufacturing facilities, leather and fur process or manufacturing facilities, rubber and plastic products manufacturing facilities, metal products manufacturing facilities, publishing, printing, film processing and recording media reproducing facilities, wood pulp, paper and paper product manufacturing facilities, etc. The categories of industries in which heavy metal and other pollutants are classified as the main wastewater composition included 13 categories of industry such as the primary steel making facilities, leather and fur processing or leather and fur products making facilities, plating facilities, semiconductor manufacturing facilities, hospital facilities and textile dyeing and processing facilities. Indirect discharge facilities that exceed allowable standards after treatment were 2,557 industries. Among them, 87% were included in 5 types of industry and most of them were included in B (나) zone. Based on their discharge flow, type 1 that discharge exceeding allowable standards(29 facilities), showed 163, 914 tons/day, which accounts for 64% of the whole discharge flow. Type 2(39 facilities) accounted for 14% of the whole discharge flow with 36,536 tons/day. By regional groups, those facilities in B (나) zone proved to be the highest in discharge flow. Also, as a result of examining those facilities’ release exceeding allowable discharge flow after treatment of water pollutants, 90% of them were proven to exceed general pollutants. The main category of industry that exceed organic matter and nutritive salts were 22 including other foods manufacturing facilities, other basic organic compound manufacturing facilities, other textile goods manufacturing facilities, and pulp, paper and paper products making facilities. Other foods manufacturing facilities and seasoning and food additives manufacturing facilities were analyzed into the main type of industry exceeding BOD, COD, SS, TN and TP. As a result of analyzing the category of industry included in 34 priority control watersheds in the four rivers, targeting type 1 and type 2, which were the most in discharge flow among the category of industry that exceed general pollutants, those were proven to be 15 facilities such as the semiconductor and electronic components manufacturing facilities (type 1, one facility; type 2, two facilities), pulp and paper and paper goods manufacturing facilities (type 1, one facility; type 2, one facility), textile dyeing and processing facilities (type 2, six facilities), plating facilities (type 2, one facility), waterworks facilities (type 2, one facility), non-alcoholic beverages and ice manufacturing facilities (type 2, one facility) and glass and glass products manufacturing facilities (type 1, one facility). Facilities that exceed allowable discharge standards after treatment by heavy metals and other pollutants were included in type 3~5, excepting type 1, one facility, and type 2, two facilities, which exceed allowable discharge standards for n-hexane. Meanwhile, as a result of examining the status of recording concentration, targeting type 1 and type 2, whose main wastewater compositions are heavy metals and other pollutants, the rate of recording the concentration was found to be very poor. This resulted in a shortage of data, and consequently we couldn't clearly figure out if they exceeded allowable discharge standards or not. That is why systematic monitoring of those types of industries should be required. This study examined the indirect wastewater discharge facilities belonging to 34 watersheds in the four rivers among wastewater discharge facilities as the priority control target for ecotoxicology that is applied to only direct discharge, targeting type 1 and type 2. As a result, 16 types of industry, including 163 factories, were found. Since they were exempted from ecotoxicology control, pollution source management of them was not clear. 3. Policy proposal For more scientific and systematic management of the indirect wastewater discharge facilities, this study suggests a selective water quality TMS attachment and a need for applying an ecotoxicology management system and the targets to apply in consideration of the industrial wastewater's characteristics, category of industry and regions (priority management zone). 1) Water quality TMS attachment of the indirect wastewater discharge facilities and its selective target facilities Strengthening control of 22 wastewater discharge facilities exceeding allowable discharge standards included in the category of industry whose general water pollutants are analyzed as the main water pollutants of wastewater should be required. Among them, those in type 1 and type 2 were found 44 facilities in 15 categories of industry (17 facilities of type 1; 27 facilities of type 2). In particular, since two industries as pulp, paper and paper goods manufacturing facilities, six industries as textile dyeing and processing facilities and one plating facility belong to 34 watersheds in the four rivers, they could be the priority target to apply. 2) Ecotoxicology management of the indirect wastewater discharge facilities and selective target facilities In Korea, ecotoxicology management is only applied to the direct discharge facilities. Since indirect discharge facilities are free from ecotoxicology management, it is difficult to manage the place of origin of ecotoxicology source in the public sewage and wastewater treatment plant that is the final disposal facility. Therefore, in case of the wastewater discharge facilities whose main water pollutants are harmful substances such as heavy metal, even if they take indirect discharge, applying ecotoxicology management system to type 1 and type 2 industries that have a lot of outflow should be recommended. Only in consideration of indirect discharge, it should be applied to the 34 priority control watersheds in the four rivers first, and then based on the outcomes and results, a measure of expanding it should be considered. This study is to suggest a guideline based on 「National Pollution Source Investigation Report」. On the basis of the results of continuously monitoring and evaluating the fields of the main types of industry, applying stage by stage from 34 priority control watersheds in the four rivers where strict management is required is recommended. In case of water quality TMS attachment, the financial burden on the businesses has been brought up continuously because of self-pay of TMS installation and operating cost. Preparing a financial support plan for them should be required. 3) Role strengthening of the public wastewater treatment plant If legal authority and responsibility are given to the public wastewater treatment plants, they will have a high sense of responsibility to monitor the wastewater inflow from the indirect discharge facilities. Thus, role strengthening of the public wastewater treatment plant should be required. 4) Construction of a national wastewater DB Although industrial wastewater greatly affects water systems, nearly the only national statistics having the public's trust are data from the national pollution source investigation report that has been conducted annually under Article 23 of The Law on Water Quality and Water Ecosystem Conservation. Therefore, securing data and constructing a national DB are urgently needed so that more accurate statistical analysis could be made. This is basic material definitely needed for more advanced management which is appropriate for the changing status of industrial wastewater discharge and for constructing a differentiated wastewater management system that reflects characteristics by category of industry, regional groups and wastewater treatment technologies.

Recent progress in microalgal biomass production coupled with wastewater treatment for biofuel generation

Salama, El-Sayed,Kurade, Mayur B.,Abou-Shanab, Reda A.I.,El-Dalatony, Marwa M.,Yang, Il-Seung,Min, Booki,Jeon, Byong-Hun Elsevier 2017 RENEWABLE & SUSTAINABLE ENERGY REVIEWS Vol.79 No.-

<P><B>Abstract</B></P> <P>Microalgae are a potential source of sustainable biomass feedstock for biofuel generation, and can proliferate under versatile environmental conditions. Mass cultivation of microalgae is the most overpriced and technically challenging step in microalgal biofuel generation. Wastewater is an available source of the water plus nutrients necessary for algae cultivation. Microalgae provide a cost-effective and sustainable means of advanced (waste)water treatment with the simultaneous production of commercially valuable products. Microalgae show higher efficiency in nutrient removal than other microorganisms because the nutrients (ammonia, nitrate, phosphate, urea and trace elements) present in various wastewaters are essential for microalgal growth. Potential progress in the area of microalgal cultivation coupled with wastewater treatment in open and closed systems has led to an improvement in algal biomass production. However, significant efforts are still required for the development and optimization of a coupled system to simultaneously generate biomass and treat wastewater. In this review, the systematic description of the technologies required for the successful integration of wastewater treatment and cultivation of microalgae for biomass production toward biofuel generation was discussed. It deeply reviews the microalgae-mediated treatment of different wastewaters (including municipal, piggery/swine, industrial, and anaerobic wastewater), and highlight the wastewater characteristics suitable for microalgae cultivation. Various pretreatment methods (such as filtration, autoclaving, UV application, and dilution) needed for wastewater prior to its use for microalgae cultivation have been discussed. The selection of potential microalgae species that can grow in wastewater and generate a large amount of biomass has been considered. Discussion on microalgal cultivation systems (including raceways, photobioreactors, turf scrubbers, and hybrid systems) that use wastewater, evaluating the capital expenditures (CAPEX) and operational expenditures (OPEX) of each system was reported. In view of the limitations of recent studies, the future directions for integrated wastewater treatment and microalgae biomass production for industrial applications were suggested.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Challenges in using wastewater for microalgae cultivation and biomass production. </LI> <LI> Treatment of different wastewaters and reuse of the treated water. </LI> <LI> Recovery of valuable nutrients (N/P) and removal of organic pollutants. </LI> <LI> Application of wastewater in raceways, photobioreactors, turf scrubbers, and hybrid systems. </LI> <LI> Genetically engineered microalgae for efficient wastewater treatment. </LI> </UL> </P>

E-PFR 반응기를 이용한 유기성 폐기물의 혐기성 처리와 재생에너지 생산에 관한 연구

김범식(Burmshik Kim),최홍복(Hong-Bok Choi),이재기(Jae-Ki Lee),박주형(Jae-Ki Lee),지덕기(Duk Gi Ji),최은주(Eun-Ju Choi) 유기성자원학회 2008 유기물자원화 Vol.16 No.2

일반적 중·저농도형 하수처리시설을 통해서는 처리가 힘든 고농도 유기성 폐수의 경우 재생에너지 생산이 가능한 혐기성 분해로 처리하는 것이 유리하다. 기존 호기성 처리에서 이미 그 실용성과 우수성이 입증된 E-PFR을 혐기성 처리에 적용하여 그 효용성과 재생에너지 생산 효율 증대 효과 등을 검증하고, 효율적인 재생에너지 생산을 위한 조건 등을 제시하기 위한 연구를 수행하였다. N 음식물쓰레기 처리시설에서 발생하는 탈리액을 대상으로 수행한 Pilot Plant 규모의 실험 연구에서 반응기의 구조적 특성으로 인해 혐기성 분해의 효율 향상 및 메탄가스 발생량이 증가함을 확인 하였다. 이러한 처리 효율의 향상은 유체 이동관과 각단을 분리하는 격벽을 설치한 E-PFR의 구조적특성에 기인한 원활한 혼합조건 형성과 스컴제어로 혐기성 처리에 있어서도 매우 이상적인 반응 조건을 형성시키기가 용이하였기 때문이다. E-PFR은 상향류식 폐수 유입과 각 단별로 분리된 다단형 처리로 인해 폐수 유입 구역에는 상대적으로 높은 MLSS가 유지될 수 있으므로 충격부하에 대한 내성이 강하고, 전체적으로 혐기성 최적 pH인7.0~8.0 정도를 유지하여 상대적으로 높은 가스 발생량 및 메탄가스 함량을 유지하는 것이 가능하였다. 뿐만 아니라, 각 단별로 각기 다른 MLSS를 유지시키면서 SRT를 상대적으로 길게 유지함으로써 유기물 분해 및 가스 발생 효율을 증가시키는 효과가 있었다. 향후, 반응기의 구조적 개선과 발생가스를 이용한 교반 효과 개선 등을 통해 메탄가 스 함량 70 % 수준의 안정적 혐기성 분해가 가능한 실증 플랜트 설계가 가능할 것으로 판단되며, 이를 통해 한층 향 상된 재생에너지 획득 시스템 확보가 가능할 것이다. Wastewater containing strong organic matter is very difficult to treat by utilizing general sewage treatment plant, but the wastewater is adequate to generate biomass energy (bio-gas; methane gas) by utilizing anaerobic digestion. EcoDays Plug Flow Reactor (E-PFR), which was already proved as an excellent aerobic wastewater treatment reactor, was adapted for anaerobic food wastewater digestion. This research was performed to improve the efficiency of bio-gas production and to optimize anaerobic wastewater treatment system. Food wastewater from N food waste treatment plant was applied for the pilot scale experiments. The results indicated that the efficiency of anaerobic wastewater treatment and the volume of bio-gas were increased by applying E-PFR to anaerobic digestion. The structural characteristics of E-PFR can cause the high efficiency of anaerobic treatment processes. The unique structure of E-PFR is a diaphragm dividing vertical hydraulic multi-stages and the inversely protruded fluid transfer tubes on each diaphragm. The unique structure of E-PFR can make gas hold-up space at the top part of each stage in the reactor. Also, E-PFR can contain relatively high MLSS concentration in lower stage by vertical up-flow of wastewater. This hydraulic flow can cause high buffering capacity against shock load from the wastewater in the reactor, resulting in stable pH (7.0~8.0), relatively higher wastewater treatment efficiency, and larger volume of bio-gas generation. In addition, relatively longer solid retention time (SRT) in the reactor can increase organic matter degradation and bio-gas production efficiency. These characteristics in the reactor can be regarded as "ideal" anaerobic wastewater treatment conditions. Anaerobic wastewater treatment plant design factor can be assessed for having 70 % of methane gas content, and better bio-gas yielding and stable treatment efficiency based on the results of this research. For example, inner circulation with generated bio-gas in the reactor and better mixing conditions by improving fluid transfer tube structure can be used for achieving better bio-gas yielding efficiency. This research results can be used for acquiring better improved regenerated energy system.

Analysis of Key Technologies for Industrialized Treatment of Fatty Acid High-Salinity Organic Wastewater

Qinfang Lu,Byung-gon Jeong,Ping Yan,Sohee Kim,Shirong Lai,Jiancheng Liu 대한환경공학회 2020 대한환경공학회지 Vol.42 No.11

Objectives : Wastewater produced by fatty acid production contains high concentration of organic substances and high concentration of salts (mainly sodium sulfate), causing great pollution to water resources and environment. The pollution prevention and control of this type of wastewater are very necessary. The key to treating this type of wastewater is to remove salts and COD to achieve harmless treatment. This is a problem in wastewater management that has plagued the industry for a long time. This paper proposed a technique suitable for fatty acid high salinity organic wastewater. Methods : First, the industrial treatment technology of organic wastewater with high salinity was introduced and analyzed. Combined with the principle of industrial wastewater treatment, the process route for the treatment of fatty acid high salinity organic wastewater was analyzed and selected. In addition, the key technology and process for anaerobic desalination and COD removal were analyzed and selected. Results and Discussion : According to the unique nature of this type of wastewater mainly containing sulphate salts and the feasibility of industrial production, a special technology combination was proposed to treat this wastewater at this stage. Since this wastewater has a B/C ratio of 0.4 to 0.45, it is easier to use biological treatment method. Thus, the conventional treatment method is pretreatment + biological treatment. Biological enhancement and reactor process optimization can be studied for better efficiency. Conclusions : Considering the high COD and sulphate concentration characteristics of fatty acid high-salinity organic wastewater, high-efficiency anaerobic biochemical treatment is mainly considered. Combined with modern high-efficiency anaerobic suspended sludge granule technology, it was concluded that pretreatment + high efficiency IC anaerobic + secondary biological treatment can achieve industrialized treatment of such wastewater in a targeted, low-cost and reliable way. In the later stage, bio-enhancement of the anaerobic process as well as structural and process optimization of the reactor can be carried out to obtain better technical and economic results in production practice.

실제 하수조건에서 고지질 함량 조류자원의 생체생성과 하수처리 특성 분석

이장호(Jang Ho Lee),박준홍(Joon Hong Park) 大韓環境工學會 2010 대한환경공학회지 Vol.32 No.4

하수나 폐수를 이용해서 조류를 배양하고 이를 통해서 획득된 조류 생체로부터 바이오디젤을 생산한다는 것은 친생태적이면서 신재생에너지 생산이라는 점에서 최근 각광받는 녹색성장기술이다. 바이오디젤 생산에 필요한 지질의 함량이 높은 조류 종에 대한 연구가 최적 인공배양액 조건에서 연구된 사례들이 있다. 하지만 실제 하수의 조건에서 고지질 함량 조류의 생체생성과 하수처리능에 대한 정보 제공이 미흡한 것이 현황이다. 본 연구에서는 바이오디젤 전구물질인 지질함량이 높다고 알려진 조류 종들을 선별해서 국내 하수조건에서 생체생성능과 하수처리능을 분석하였다. 이를 위해서 실제 하수에서 토착조류를 제거한 후 지질함량이 높다고 알려진 조류 4종(Chlorella vulgaris AG10032, Ankistrodesmus gracilis SAG278-2, Scenedesmus quadricauda, Botryococcus braunii UTEX 572)을 각각 하수에 식종한 후에 조류의 성장률과 유기물, 질소 및 인의 제거를 실험실 규모의 회분식반응조에서 분석하였다. 일정한 광반응 조건 (80 μE, 24시간)에서 9일간 배양하면서 시간 별로 조류의 건조 생체량과 COD, 질소 및 인을 각기 측정하였다. 그 결과 C. vulgaris, A. gracilis와 S. quadricauda는 하수의 토착조류 보다 하수에서 더 우월하게 성장하는 것을 알 수 있었다. 반면 B. braunii는 하수조건에서 성장을 할 수 없는 것으로 나타났다. 하수에서 배양가능한 조류들에 의한 질소 (Total-N, NH₄+-N)와 인(Total-P, PO₄3--P)의 제거능이 우수하였고, 하수처리 방류수질 기준을 만족하였다. 하수에서 배양가능한 조류들에 의한 용존 COD의 제거 분석 결과, A. gracilis와 S. quadricauda는 효과적인 COD제거를 지속하였지만, C. vulgaris는 초기의 COD 제거가 지속되지 않는 불안정성을 보였다. 이러한 결과들을 종합적으로 고려해서 본 연구에서는 A. gracilis와 S. quadricauda를 실제 하수에 적응성과 처리능이 우수한 조류자원으로 선정하였다. Wastewater treatment using algal communities and biodiesel production from wastewater-cultivated algal biomass is a promising green growth technology. In literature, there are many studies providing information on algal species producing high content of lipid. However, very little is known about adaptability and wastewater treatability of such high-lipid algal species. In this study, we attempted to characterize algal biomass production and wastewater treatability of high-lipid algal species under municipal wastewater condition. For this, four known high-lipid algal strains including Chlorella vulgaris AG 10032, Ankistrodesmus gracilis SAG 278-2, Scenedesmus quadricauda, and Botryococcus braunii UTEX 572 were individually inoculated into municipal wastewater where its indigenuous algal populations were removed prior to the inoculation, and the algae-inoculated wastewater was incubated in the presence of light source (80μE) for 9 days in laboratory batch reactors. During the incubations, algal biomass production (dry weight) and the removals of dissolved organics (COD), nitrogen and phosphorous were measured in laboratory batch reactors. According to algal growth results, C. vulgaris, A. gracilis and S. quadricauda exhibited faster growth than indigenuous wastewater algal populations while B. braunii did not. The wastewater-growing strains exhibited efficient removals of total-N, NH₄+-N, Total-P and PO₄3--P which satisfy the Korea water quality standards for effluent from municipal wastewater treatment plants. A. gracilis and S. quadricauda exhibited efficient and stable treatability of COD but C. vulgaris showed unstable treatability. Taken together with the results, A. gracilis and S. quadricauda were found to be suitable species for biomass production and wastewater treatment under municipal wastewater condition.

Influence of Municipal Wastewater on Rice Seed Germination, Seedling Performance, Nutrient Uptake, and Chlorophyll Content

Adam Bin Puteh,Umaru Mohamed Gassama,Mohamed Ridzwan Abd-Halim,Bashiru Kargbo 한국작물학회 2015 Journal of crop science and biotechnology Vol.18 No.1

The sand medium experiment was conducted in the laboratory with the aim of evaluating the suitability of municipal wastewater (treated and untreated) at different concentrations (0, 2.5, 5, 10, 25, 50, and 100%) for irrigation purposes on seed germination, seedling performance, nutrient uptake, and chlorophyll content of rice (MR220). The utilization of municipal wastewater for irrigation purposes has developed an important way to exploit the nutrients it contains. The study indicated a significant (P < 0.05) difference between untreated and treated municipal wastewater for seedling length (SL), root volume (RV), root surface area (RSA), seedling vigor index (SVI), and root : shoot ratio (R : S) while no significant different was observed between untreated and treated municipal wastewater for germination percentage (GP) and percentage phytotoxicity (PPT). The municipal wastewaters had stimulatory effect on the rice seeds at lower wastewater concentrations (< 25%) while inhibitory effect was observed at higher wastewater concentrations (> 50%). N, P, K, Ca, Mg, Zn, Fe, Cu, and Mn were high in the untreated municipal wastewater compare to treated municipal wastewater. Seedlings irrigated with untreated municipal wastewater have high seed germination, seedling performance with high nutrient uptake compare to treated municipal wastewater. The municipal wastewaters showed inhibitory effect on chlorophyll content. The inhibition effect was observed at > 50% concentration of both untreated and treated municipal wastewater while promoting effects were observed at lower (< 25%) concentration. The rice MR220 variety showed better growth resistance, tolerance, and adaptability to wastewater. This can be due to its excellent genetic makeup and capacity to sustain the toxicity. Conclusively, municipal wastewater could be recommended as a good source of water and nutrient for seed germination and seedling performance.

고객가치를 고려한 하수도 시설의 서비스 수준 평가

한상종,황환국,정연규 대한상하수도학회 2011 상하수도학회지 Vol.25 No.6

In this study, we derived seven customer value factors to evaluate the levels of service in wastewater utilities required by customers. Levels of service according to the customer value were categorized into environmental amenity, accessibility of wastewater service, affordability of wastewater charge, quality of wastewater service, health and safety of wastewater service provision, reliability and responsiveness of wastewater service provision, and satisfaction of customer service. To investigate the levels of wastewater service, questionnaires were prepared according to the customer value factors, and the questionnaire survey was performed with 800 adults in all over Korea including male and female samples. The comprehensive satisfaction score for the wastewater service was 57.5 points, indicating a slightly good satisfaction level. The detailed analysis of the result showed that the satisfaction level was high in the wastewater service accessibility and call center service provision but it was relatively low in the river water quality and nasty smell of wastewater. It was concluded that the quality of wastewater service and customer service satisfaction need to be elevated primarily in order to improve levels of wastewater service required by the customers.

PACS 도입에 의한 현상시스템 폐수 감소효과에 관한 연구

고신관(Shin-Kwan Ko),양한준(Han-Jun Yang),한동균(Dong-Kyoon Han),김욱동(Wook-Dong Kim),강병삼(Bung-Sam Kang) 대한방사선과학회(구 대한방사선기술학회) 2007 방사선기술과학 Vol.30 No.2

  2001년부터 본격적으로 보급되기 시작한 PACS 도입은 영상의학과에서는 필름비용 절감, 인건비 절감, 현상액 사용량 절감, 관리업무 축소, 재 촬영 건수의 감소 등의 효과를 볼 수 있었고, 임상 의사들에게는 의료영상동시 활용, 임상정보의 증대, 진료 환자수의 증가, 의료영상 및 판독결과 활용성 증대 효과를 기대할 수 있는 것으로 알려져 있다.<BR>  환자들에게는 방사선 피폭선량 감소, 진료비 절감, 임상정보를 신속하게 알 수 있는 효과가 있다. 이에 본 저자들은 Full PACS를 도입한 서울 및 경기도의 10개 종합병원을 대상으로 하여 PACS로 인한 긍정적인 여러가지 효과 중 현상, 정착 폐수의 감소 추이를 알아보기 위하여 도입 1년 전과 도입 3년 후를 비교 분석하여 다음과 같은 결론을 얻었다.<BR>  1. 1개월 당 검사 건수는 7357.7건이 증가하였으나 필름 사용량은 90%가 감소하였다.<BR>  2. 현상액 월 평균 소모량은 3년 후 92%가 감소하였고, 정착액은 86%가 감소하였다.<BR>  3. 필름 1장 당월 평균 현상액 소모량은 3년 후 149%가 증가하였고, 정착액은 300%가 증가하였다.<BR>  4. 현상 폐수 발생량은 3년 후 월 평균 88%가 감소하였고, 정착 폐수는 87%가 감소하였다.<BR>  5. 3년 후 필름 1장 당월 평균 현상폐수 발생량은 377%, 정착폐수 발생량은 385%가 증가하였다.   There are some positive effects by the introduction of PACS(Picture Archiving Communication System). This study is to analyze the mutual relation between before and after of the introduction of PACS in terms of the environment effect. It is supposed to cause the reduction of developing and fixing wastewater according to the increase in the rate of a non-film. This study will also show the amount of wastewater.<BR>  Target places were the department of image medicine(diagnostic radiation) of the general hospitals in Seoul and Gyeonggi-Do, which are equiped with full PACS. The authors examined questionnaires on the number of projection, the number of indirect projection, the amount of the film used, the number of radiation image CD loan, the amount of the developing and fixing solution used, the change of the amount of fixing wastewater.<BR>  According to the analysis, we analyzed the change of the amount of developing and fixing solution per a film and the change of the amount of developing and fixing wastewater which is supposed to be reduced proportionally by the introduction of PACS.<BR>  We got conclusion as below after analyzing 8 hospitals except the largest and the least amount of examination, film used, developing and fixing solution and the amount of developing and fixing wastewater in order to decrease the deviation from 10 general hospitals located in Seoul and Gyeonggi- Do. We compared data one year before adopting PACS Versus 3 years after adopting PACS.<BR>  1. The frequences of examination increased to 7,357.7 cases per month but the amount of film used decreased to 90%, from 42,774.4 to 4,181.88 after adopting the PACS.<BR>  2. 3 years after adopting PACS, monthly average amount of developing solution used decreased to 92% and the monthly average amount of fixing solution decreased to 86%.<BR>  3. Monthly average amount of developing solution used per film increased to 1.49 times and fixing solution increased as much as three times.<BR>  4. Monthly average wastewater for developing decreased to 88% and wastewater for fixing decreased up to 87%.<BR>  5. Monthly average wastewater for developing per film increased to 3.77 times and wastewater for fixing increased to 3.85 times.<BR>  Although the amount of film used and the amount of developing and fixing wastewater affected by the reduction of the developing and fixing solution became less on the whole by introduction of PACS, they did not decrease proportionally.<BR>  Moreover the amount of the developing and fixing solution used and the amount of developing and fixing wastewater per a film increased. That means the expectation for an environmental improvement differs from the actual condition.

Performance of Combined Application of ARF and RO - Removal of COD and TSS in Various Chemical Wastewater -

( Mohammad N. Islam ),( Hoi N. Yang ),( Han S. Yang ),( Keum J. Park ) 한국농업기계학회 2010 한국농업기계학회 학술발표논문집 Vol.15 No.1

This research paper focuses on a design of a feasible and efficient technique for the reuse of industrial chemical wastewater. Combination techniques of the automatic restore filter (ARF) and reverse osmosis (RO) can be one of the possible solutions for treating industrial chemical wastewater. In this study, four types ( tin wastewater, Fine chemical industry wastewater, mixed chemical wastewater and Kumho chemical industry wastewater) of industrial chemical wastewater was evaluated using combined ARF and RO pilot plant, on the basis of COD, TN and TSS removal efficiency. Experiment was carried out using continuous flow operation system. Analyzing the all samples, we obtained the highest removal efficiency of COD, TN and TSS, 98.2%, 98.9% and 90.0%, respectively from tin wastewater. Also the removal efficiencies of Fine chemical industry wastewater, mixed chemical wastewater and Kumho chemical industry wastewater for COD, TN and TSS were 99.5%, 93.2%, 62.6%; 69.9%, 77.8%,95.0% and 99.8%, 86.9%, 99.0%, respectively. The results indicate that the combination of ARF and RO is a good technique for treating industrial chemical wastewater.