Comparison of two anaerobic systems for hydrogen production from the organic fraction of municipal solidwaste and syntheticwastewater

International Journal of Hydrogen Energy 32 (2007) 3141 – 3146
www.elsevier.com/locate/ijhydene

Comparison of two anaerobic systems for hydrogen production from the
organic fraction of municipal solid waste and synthetic wastewater
Liliana M. Alzate-Gaviria a , P.J. Sebastian a , b , ∗ , Antonino Pérez-Hernández c , D. Eapen b
a Centro de Investigación en Energía-UNAM, 62580 Temixco,Morelos, Mexico
b Universidad Politécnica de Chiapas, 29010 Tuxtla Gutiérrez, Chiapas, Mexico
c Centro de Investigación en Materiales Avanzados, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua 31109, Mexico

Received 22 November 2005; received in revised form 26 January 2006; accepted 11 February 2006
Available online 2 April 2007

Abstract
Two laboratory scale anaerobicdigestion systems for hydrogen production from organic fraction of municipal solid waste (OFMSW) and
synthetic wastewater were compared in this study. One of them was formed by a coupled packed bed reactor (PBR) containing 19.4 L of
OFMSW and the other an upflow anaerobic sludge bed (UASB) of 3.85 L. The reactors were inoculated with a mixture of non-anaerobic inocula.
In the UASB the percentage ofhydrogen yield reached 51% v/v and 127 N mL H2 /gvs removed with a hydraulic retention time (HRT) of 24 h.
The concentration of synthetic wastewater in the affluent was 7 g COD/L. For the PBR the percentage yield was 47% v/v and 99 N mL H2 /gvs
removed with a mass retention time (MRT) of 50 days and the organic load rate of 16 gvs (Grams Volatile Solids)/(kg-day). The UASB and
PBR systemspresented maximum hydrogen yields of 30% and 23%, respectively, which correspond to 4 mol H2 /mol glucose. These values
are similar to those reported in the literature for the hydrogen yield (37%) in mesophilic range. The acetic and butyric acids were present in
the effluent as by-products in watery phase. In this work we used non-anaerobic inocula made up of microorganism consortium unlike other
workswhere pure inocula or that from anaerobic sludge was used.
2007 Published by Elsevier Ltd on behalf of the International Association for Hydrogen Energy.
Keywords: Hydrogen production; Anaerobic digestion; Packed bed reactor; Up-flow anaerobic sludge bed reactor.

1. Introduction
Garbage constitutes many problems for humanity, especially
in the big cities where a lot of population isconcentrated. Due
to the modern way of life, increased human activities and consumption, the amount of garbage generated increases day by
day. The industrialized world depends largely on petroleum
and its derivatives for the energy needs. Nevertheless, the concerns on diminishing petroleum reserves and the impact of its
increased use on environment are on the rise. In this context
hydrogen isconsidered as the energy vector connecting the primary renewable energy sources and the end use.
The anaerobic digestion of organic waste typically produces
methane that can be used as a renewable fuel in power plants,
∗ Corresponding author. Centro de Investigación en Energía-UNAM, 62580
Temixco, Morelos, Mexico. Tel.: +52 55 56229706; fax: +52 777 3250018.
E-mail address: sjp@cie.unam.mx (P.J.Sebastian).

automobiles, fuel cells, etc. A gaseous by-product formed during acido-genesis of the anaerobic digestion is hydrogen, which
is considered as the alternative renewable fuel for the applications mentioned above [1]. Hydrogen possesses an energy content of 122 kJ/g, that is to say, 2.75 times more energy content
than any other hydrocarbon fuel [2]. One of the main applications ofhydrogen is in fuel cells to produce electricity through
an electrochemical process. The feasibility of employing acidogenesis of organic waste to produce hydrogen has been demonstrated in various laboratories [2–4].
The advantages of hydrogen production by anaerobic fermentation are that many fermentative bacteria are capable of
high yield of hydrogen and hydrogen is produced throughout
day and...