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Class objectives Understand.. the physical, chemical, and biological characteristics of water that determines its quality and methods for analysis the planning, design, and maintenance of wastewater collection and treatment systems the principles and practices of unit processes used for wastewater treatment And discuss.. the current issues of sustainable water resource and quality management 2
Course material & textbook 1. Lecture notes 2. Metcalf, Eddy, AECOM, Wastewater Engineering: Treatment and Reuse, 5 th ed., McGraw Hill, 2014 3. Tchobanoglous, Schroeder, Water Quality: Characteristics, Modeling, Modification, Science, 1985 3
Instructor: Prof. Yongju Choi Office : 35 307 (welcome for discussion by appointments) Email: ychoi81@snu.ac.kr Evaluation Midterm [25%] / Final [25%] Homework assignment [15%] Attendance [10%] / Class participation [5%] Term Project [20%] 4
Homework assignment Every three weeks, due a week after Term Project A case study report for currently developing water quality management systems employing at least one of the following concepts: Wastewater reuse Stormwater (rainwater) management Resource and energy recovery Decentralized wastewater treatment 1 page proposal in May, 6 8 page term paper in June In class presentation in the last day of class 5
Garbage thrown on streets, human waste stacked in backyards Liquid wastes thrown to gutters or drywells Hydrogen sulfide gases (odor problems), methane accumulation (explosions) Transmission of diseases 1893 New York: Schmidt, 2010, on earth 6
Several Cholera outbreaks in Europe in 1800s Dr. John Snow tracked victims of cholera outbreak in London in 1853 High incidence of deaths for people obtaining drinking water from a well Later it was found that the mother of an infant who died from cholera dumped feces containing water into the cesspool less than 1 m away from the well Davies & Masten, Principles of Environmental Engineering and Science, 2014 7
The Great stink Serious odor problems in central London in the summer of 1858 Partially because of the introduction of flush toilets Human waste and wastewater generated from factories, slaughterhouses, etc. all drained into the Thames river without any treatment (and people pumped back the river water to drink!) The odor was so bad that it affected the work of the House of Commons A bill to construct new sewers and embankment along the Thames was rushed through Parliament and became law in 18 days 8
I traversed this day by steam boat the space between London and Hangerford Bridges The whole of the river was an opaque pale brown fluid. In order to test the degree of opacity, I tore up some white cards into pieces, moistened them so as to make them sink easily below the surface, and then dropped some of these pieces into the water at every pier the boat came to; before they had sunk an inch below the surface they were indistinguishable, though the sun shone brightly at the time; and when the pieces fell edgeways the lower part was hidden from sight before the upper part was under water (The Times, 1855) http://www.wikipedia.com 9
River caught on fire Oily waste released to the river from industry Floating pieces of oil slick debris on the river Spark caused by a passing train on the bridge put on fire on the river Caused significant damages including the destruction of bridge Cuyahoga River Fire, Nov 03, 1952: http://www.ohiohistorycentral.org 10
낙동강페놀유출사고 (1991) 1991년 3월 14일오후 10시 ~ 15일오전 6시까지 8시간동안경북구미시두산전자에서페놀원액 30톤이낙동강지류인옥계천에누출되었다. 원료인페놀을공급하는파이프라인의이음새가파열된것이원인이었다. 오염된낙동강물은 16일대구시수돗물의 70% 를공급하는다사수원지에유입됐고다시수돗물로만들어져대구시에공급되었다. 페놀에오염된수돗물을마신수돗물을마신시민들은구토 설사 복통으로고통을겪었으며수돗물로만든두부 김치 콩나물등은악취때문에폐기처분하는사태가발생하였다. 특히정수장에서는페놀이염소소독제와결합하면악취가최고 1 만배나증가하는클로로페놀이생성된다는사실도알지못한채무턱대고소독제만쏟아부어피해를키웠다. 11
낙동강페놀유출사고 (1991) 두산전자는한달간의조업정지를당했으나수출에타격을준다는명분에따라보름만에조업을재개하였다. 그러나 4 월 22 일소량의페놀이또다시유출되어 14 시간동안대구시가수돗물취수를중단하는상황이발생하였다 (2 차사고 ). 출처 : 친수하천의수질사고발생시대응방안연구, 서울연구원정책과제연구보고서 http://www.bizwatch.co.kr 12
낙동강하구어패류폐사사고 (1996) 1996 년 6 월 19 일경상도일대에쏟아진폭우로낙동강의수위조절을위해하구언수문을개방한뒤 6 월 20 일부터 6 월 23 일까지 4 일동안에걸쳐낙동강하구언상류및하류해안가에물고기와조개류가약 5 톤정도폐사하였다. 물고기는하구언을중심으로상류에서낙동강지류인엄궁천이합류되는지점과하류의장림천, 보덕천합류지점등에서폐사하였으며, 피해어종은웅어가약 90% 를차지하였고나머지는누치등이었다. 한편조개류는해안가인다대포앞에서폐사하였다. http://www.americathebeautifulconspiracy.com 13
하수처리의목적 ( 하수도법 ) 하수와분뇨를적정하게처리하여지역사회의건전한발전과공중위생의향상에기여하고공공수역의수질을보전 US EPA (Environmental Protection Agency) Maintain the water body fishable and swimmable Currently, increasing interest in ecosystem value Protecting the aquatic ecosystem in the water body 14
So, the goal of wastewater management is, in general: Drain wastewater from the area where human life occur so that their contact to wastewater can be minimized Treat wastewater before it is discharged to maintain the water quality of the natural waters for the benefit of humans and aquatic ecosystem Wastewater management goal can be changed in the future More emphasis on sustainability and urban water cycle Reusing treated water, energy and resource recovery from wastewater 15
환경정책기본법 (1990. 8. 1): 환경보전에관한국민의권리 의무와국가의책무를명확히하고환경정책의기본이되는사항을정함 환경정책기본법시행령 : 하천 / 호소 / 해역의사람의건강보호, 생활환경, 수생태계보호기준명시 < 하천 사람의건강보호기준 > 항목 기준값 (mg/l) 항목 기준값 (mg/l) 카드뮴 <0.005 폴리클로리네이티드비페닐 <0.0005 비소 <0.05 사염화탄소 <0.004 납 <0.05 테트라클로로에틸렌 <0.04 6가크롬 <0.05 벤젠 <0.01 16
< 하천 생활환경기준 > 17
수질및수생태계보전에관한법률 (2005. 3. 31): 수질오염으로인한국민건강및환경상의위해를예방하고하천 해역등공공수역의수질및수생태계를적정하게관리 보전 시행규칙 : 수질오염물질, 특정수질유해물질, 폐수종말처리시설의방류수수질기준, 수질오염물질의배출허용기준등지정 수질오염물질 : 수질오염의요인이되는물질 (53종) 특정수질오염물질 : 수질오염물질중사람의건강, 재산이나동식물의생육에직접또는간접으로위해를줄우려가있는물질 (28종) 18
폐수종말처리시설의방류수수질기준 (2013. 9. 5. 개정 ) 항목 I지역 II지역 III지역 IV지역 BOD (mg/l) <10 <10 <10 <10 COD (mg/l) <20 <20 <20 <20 부유물질 (mg/l) <10 <10 <10 <10 총질소 (mg/l) <20 <20 <20 <20 총인 (mg/l) <20 <20 <20 <2 총대장균군수 ( 개 /ml) <3000 <3000 <3000 <3000 생태독성 (TU) <1 <1 <1 <1 19
수질오염물질의배출허용기준 (2013. 9. 5. 개정 ) 대상규모배출량 2000 m 3 /d 이상배출량 2000 m 3 /d 이하 항목 BOD COD SS BOD COD SS 청정지역 <30 <40 <30 <40 <50 <40 가지역 <60 <70 <60 <80 <90 <80 나지역 <80 <90 <80 <120 <130 <120 특례지역 <30 <40 <30 <30 <40 <30 20
기타관련법률 하수도법 : 하수도의설치및관리의기준정함 오염총량제에따른유역별관리 한강수계상수원수질개선및주민지원등에관한법률 금강수계물관리및주민지원등에관한법률 낙동강수계물관리및주민지원등에관한법률 영산강 섬진강수계물관리및주민지원등에관한법률 21