1 SPECIALIZED ENGLISH-SEMESTER 5 VAN LANG UNIVERSITY DEPARTMENT OF ENVIRONMENTAL TECHNOLOGY AND MANAGEMENT Chapter 2.11Chapter 2.11 FUNDAMENTALS OF BIOLOGICAL FUNDAMENTALS OF BIOLOGICAL Dr. Tran Thi My Dieu Sep. 2011 VAN LANG UNIVERSITY DENTEMA WASTEWATER TREATMENTWASTEWATER TREATMENT Anaerobic fermentation and oxidationAnaerobic fermentation and oxidation CONTENTSCONTENTS Process descriptionProcess description MicrobiologyMicrobiology VAN LANG UNIVERSITY DENTEMA Stoichiometry of biological nitrificationStoichiometry of biological nitrification Environmental factorsEnvironmental factors PROCESS DESCRIPTIONPROCESS DESCRIPTION VAN LANG UNIVERSITY DENTEMA PROCESS DESCRIPTIONPROCESS DESCRIPTION VAN LANG UNIVERSITY DENTEMA PROCESS DESCRIPTIONPROCESS DESCRIPTION VAN LANG UNIVERSITY DENTEMA MICROBIOLOGYMICROBIOLOGY Nonmethanogenic microorganisms responsible for hydrolysis & fermentation consists of facultative and obligate anaerobic bacteria The microorganisms responsible for CH 4 production, classified as archaea are strict obligate anaerobes VAN LANG UNIVERSITY DENTEMA Clarifier classified as archaea , are strict obligate anaerobes Methanosarcina & Methanothrix (also termed Methanosaeta) are the only organisms able to use acetate to produce CH 4 & CO 2 Nuisance organisms (sulfate-reduction bacteria) 2 STOICHEOMETRYSTOICHEOMETRY 4H 2 + CO 2  CH 4 + 2H 2 O 4HCOO - + 4H +  CH 4 + 3CO 2 + 2H 2 O 4CO + 2H 2 O  CH 4 + 3CO 2 VAN LANG UNIVERSITY DENTEMA Clarifier 2 4 2 4CH 3 OH  3CH 4 + CO 2 + 2H 2 O 4(CH 3 ) 3 N + H 2 O  9CH 4 + 3CO 2 + 6H 2 O + 4NH 3 CH 3 COOH  CH 4 + CO 2 ENVIRONMENTAL FACTORSENVIRONMENTAL FACTORS pH > 6.8 Alkalinity ~ 3,000-5,000 mgCaCO 3 /L VAN LANG UNIVERSITY DENTEMA NH 3, H 2 , others are inhibited the process VAN LANG UNIVERSITY DENTEMA http://www.uasb.orghttp://www.uasb.org VAN LANG UNIVERSITY DENTEMA VAN LANG UNIVERSITY DENTEMA Lan can bảo vệ Ống thu nước sau xử lý Sàn công tác Máng thu nước dạng răng cưa Thiết bò tách pha khí – lỏng - rắn Vách hướng dòng hình côn Ca à thang Ống dẫn khí VAN LANG UNIVERSITY DENTEMA Ca u thang Vỏ thiết bò Hỗn hợp nước thải Lớp bùn kỵ khí Ống bơm nước vào thiết bò UASB Bộ phận phân phối đều lưu lượng nước thải Ống thoát khí Bình hấp thụ khí Bọt khí Dung dòch NaOH 5% 3 VAN LANG UNIVERSITY DENTEMA InfluentInfluent EffluentEffluent GasGas VAN LANG UNIVERSITY DENTEMA InfluentInfluent EffluentEffluent The complete-mix suspended growth anaerobic digester InfluentInfluent EffluentEffluent ClarifierClarifier FlocculatorFlocculator VAN LANG UNIVERSITY DENTEMA Sludge recycleSludge recycle Or degasifierOr degasifier the anaerobic contact processthe anaerobic contact process GasGas GasGas GasGas GasGas EffuentEffuent VAN LANG UNIVERSITY DENTEMA The anaerobic sequencing batch reactor- ASBR InfluentInfluent FillFill ReactReact SettlingSettling DecantingDecanting Anaerobic Baffled Reactor (ABR) Gas Recycle Anaerobic Migrating Blanket Reactor (AMBR) Gas Eff Inf 4 Anaerobic Up-flow Packed-bed Reactor D=2 - 8m D = 2 - 8 m H = 3-13 m Media = 100 m 2 /m 3 Loading = 1,0-6,0 kgCOD/m 3 .day, E = 90% Up-flow Attached Growth Anaerobic Expanded Reactor (AEBR) v = 2 m/h Media = Sand, d = 0,2-0,5 mm, 2,65 kg/L, 10.000 m 2 /m 3 Porosity of media = 50% Downflow Attached Growth Processes Loading = 5-10 kg/m 3. day COVERD ANAEROBIC LAGOON HRT ~ 20-50 ngày H ~ 5-10 m . & CO 2 Nuisance organisms (sulfate-reduction bacteria) 2 STOICHEOMETRYSTOICHEOMETRY 4H 2 + CO 2  CH 4 + 2H 2 O 4HCOO - + 4H +  CH 4 + 3CO 2 + 2H 2 O 4CO + 2H 2 O  CH 4 + 3CO 2 VAN LANG. 3CO 2 VAN LANG UNIVERSITY DENTEMA Clarifier 2 4 2 4CH 3 OH  3CH 4 + CO 2 + 2H 2 O 4(CH 3 ) 3 N + H 2 O  9CH 4 + 3CO 2 + 6H 2 O + 4NH 3 CH 3 COOH  CH 4 + CO 2 ENVIRONMENTAL FACTORSENVIRONMENTAL FACTORS pH. ENVIRONMENTAL TECHNOLOGY AND MANAGEMENT Chapter 2. 11Chapter 2. 11 FUNDAMENTALS OF BIOLOGICAL FUNDAMENTALS OF BIOLOGICAL Dr. Tran Thi My Dieu Sep. 20 11 VAN LANG UNIVERSITY DENTEMA WASTEWATER TREATMENTWASTEWATER