ANAEROBIC TREATMENT OF DILUTE WASTEWATERS A THESIS SUBMITTED

294 Pages·2008·3.76 MB·Turkish

ANAEROBIC TREATMENT OF DILUTE WASTEWATERS

A THESIS SUBMITTED TO
THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES
OF
MIDDLE EAST TECHNICAL UNIVERSITY

BY

EMEL ENER ALPTEKİN

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR
THE DEGREE OF DOCTOR OF PHILOSOPHY
IN
ENVIRONMENTAL ENGINEERING

APRIL 2008
Approval of the thesis:

ANAEROBIC TREATMENT OF DILUTE WASTEWATERS

submitted by EMEL ENER ALPTEKİN in partial fulfillment of the
requirements for the degree of Doctor of Philosophy in Environmental
Engineering Department, Middle East Technical University by,

Prof. Dr. Canan Özgen
Dean, Graduate School of Natural and Applied Sciences

Prof. Dr. Göksel N. Demirer
Head of Department, Environmental Engineering

Prof. Dr. Göksel N. Demirer
Supervisor, Environmental Engineering Dept., METU

Examining Committee Members:

Prof. Dr. Celal F. Gökçay
Environmental Engineering Dept., METU

Prof. Dr. Göksel N. Demirer
Environmental Engineering Dept., METU

Prof. Dr. Ülkü Yetiş
Environmental Engineering Dept., METU

Prof. Dr. Filiz B. Dilek
Environmental Engineering Dept., METU

Prof.Dr. Ayşenur Uğurlu
Environmental Engineering Dept., Hacettepe University

Date: April 15, 2008

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I hereby declare that all information in this document has been obtained and
presented in accordance with academic rules and ethical conduct. I also
declare that, as required by these rules and conduct, I have fully cited and
referenced all material and results that are not original to this work.

Name, Last name: EMEL ENER ALPTEKİN

Signature :

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ABSTRACT

ANAEROBIC TREATMENT OF DILUTE WASTEWATERS

Alptekin, Emel Ener
Doktora, Department of Environmental Engineering
Supervisor: Prof. Dr. Göksel N. Demirer

April 2008, 267 pages

In this study, domestic wastewater was used to determine the anaerobic treatment
performances of a dilute wastewater in one-phase upflow anaerobic sludge
blanket (UASB) system and two-phase upflow anaerobic filter (UAF) and UASB
system. The acidification performances of domestic wastewater were compared in
UAF and UASB reactors. The degree of acidification is higher in UAF reactor
(31%) compared to UASB reactor (18%) at 2 h hydraulic retention time (HRT) in
the anaerobic treatment of domestic wastewaters. The effluent total volatile fatty
acid (tVFA) concentration was higher in UAF reactor than that the UASB reactor
at 2 h HRT. The total chemical oxygen demand (tCOD) removal is 40% in winter
and 53% in summer in UAF reactor at 2 h HRT. The tCOD removals in two-phase
UAF and UASB system and one-phase UASB system were 83% and 63%,

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respectively, in 4 h HRT. The conversion rate of COD removed to methane were
between 0.005 and 0.067 Nm3 methane/kg COD removed and between 0.158 and
0.233 Nm3 methane/kg COD removed in the UAF and the UASB reactor of the
two-phase system, respectively. The conversion rate of COD removed to methane
varied between 0.029 and 0.199 Nm3 methane/kg COD removed in one-phase
UASB reactor. The results of this study showed that the two-phase reactor system
consisting from UAF and UASB reactors provide a good removal of soluble
organics variations in acidification reactor and better methane productions in
UASB reactor at temperatures 20°C and 35°C through the treatment of domestic
wastewater at a HRT of 4 hours.

Key words: Domestic Wastewater, Two Phase, One Phase, Upflow Anaerobic
Filter (UAF), Upflow Anaerobic Sludge Blanket (UASB).

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ÖZ

SEYRELTİK ATIKSULARIN ANAEROBİK ARITIMI

Alptekin, Emel Ener
Doktora, Çevre Mühendisliği Bölümü
Tez Yöneticisi: Prof. Dr. Göksel N. Demirer

Nisan 2008, 267 sayfa

Bu çalışmada, seyreltik atıksuların anaerobik yöntemlerle tek fazlı yukarı akışlı
çamur yatak (YAÇY) sistemi ve iki fazlı yukarı akışlı anaerobik filtre (YAF) ve
YAÇY sistemi ile anaerobik arıtım verimlerinin belirlenmesinde evsel atıksu
kullanılmıştır. Evsel atıksu asidifikasyon performansları YAÇY ve YAF
reaktörlerinde karşılaştırılmıştır. Evsel atıksuyun anaerobik arıtımında, iki saatlik
hidrolik bekleme süresinde (HBS) asidifikasyon derecesi YAF reaktöründe
(%31), YAÇY reaktörüne (%18) göre daha fazladır. Çıkış suyundaki uçucu yağ
asidi (UYA) konsantrasyonu iki saatlik HBS’de YAF reaktöründe YAÇY
reaktörüne göre daha yüksek bulunmuştur. Toplam kimyasal oksijen ihtiyacı
(tKOİ) giderimi iki saatlik HBS’de YAF reaktöründe kış ayı için %40 ve yaz ayı
için %53 oranında bulunmuştur. Dört saatlik HBS’de, iki fazlı YAF ve YAÇY

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sisteminde ve tek fazlı YAÇY sisteminde tKOİ giderimleri sırası ile %83 ve %63
oranlarında bulunmuştur. KOİ gideriminin metana dönüşüm oranı ardışık iki-fazlı
reaktörün YAF reaktöründe ve iki fazlı sistemin ikinci fazı YAÇY reaktöründe
sırasıyla 0.005 ve 0.067 Nm3 metan/kg KOİ giderim ve 0.158 ve 0,233 Nm3
CH /kg KOİ giderim aralıklarındadır. Tek-fazlı reaktörde, KOİ gideriminin
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metana dönüşüm oranı 0.029 ve 0.199 Nm3 metan/kg KOİ giderim aralığında
değişim göstermiştir. Bu çalışmanın sonuçları, 4 saatlik HBS’de, 20ºC ve 35ºC
sıcaklıklarda, evsel atıksu arıtımında, YAF ve YAÇY reaktörlerinden oluşan iki-
fazlı reaktör sisteminin asidifikasyon reaktöründe etkili çözünmüş organik madde
değişimi ve YAÇY reaktöründe de daha iyi miktarlarda metan verimleri
sağlandığını göstermiştir.

Anahtar kelimeler: Evsel Atıksu, İki Fazlı, Tek Fazlı, Yukarı Akışlı Anaerobik
Filtre (YAF), Yukarı Akışlı Anaerobik Çamur Yatağı (YAÇY)

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To my mother, father and to the memory of Prof.Dr. Kriton Curi…

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ACKNOWLEDGEMENTS

I would like to express my deepest gratitude to my supervisor Prof.Dr. Göksel N.
Demirer for his guidance, recommendations and support throughout this research
and preparation of this thesis.

I would like to acknowledge the Supervising Committee Members, Prof.Dr. Celal
F. Gökçay and Prof.Dr. Ayşenur Uğurlu for their view of the study and valuable
recommendations. I am also grateful to the Examining Committee Members,
Prof.Dr. Ülkü Yetiş and Prof.Dr. Filiz B.Dilek for their valuable suggestions and
contributions.

My special thanks go to Gülşen Erdem and Ayça Elgin for their endless support
and being by my side all the time in spite of the long distance. I am thankful to
Aynur Yıldırım, Mehmet Ali Uslu and Deniz Yılmaz for their help and support
throughout my research.

I am also thankful to Nuray Ateş, Tuba Hande Ergüder, Seçil Türkmenoğlu,
Niğmet Uzal, Emrah Alkaya, Okan Tarık Komesli, Nergiz Oktaç, Burcu
Hacıoğlu, Onur Güven Apul, Eylem Doğan, Vedat Yılmaz and Hakan Moral for
their supports. I would also like to thank Mr. Kemal Demirtaş for his excellent
assistance in the lab.

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Finally, I am grateful to my family for their endless patience, encouragement,
support and confidence in me and for making my life easy all the time.

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