Home About Browse Search

Biogas production from thin stillage

exploring the microbial response to sulphate and ammonia

Moestedt, Jan (2015). Biogas production from thin stillage. Diss. (sammanfattning/summary) Uppsala : Sveriges lantbruksuniv., Acta Universitatis Agriculturae Sueciae, 1652-6880 ; 2015:10
ISBN 978-91-576-8218-5
eISBN 978-91-576-8219-2
[Doctoral thesis]

[img] PDF


The biogas plant in Norrköping (Tekniska verken i Linköping AB, publ.), Sweden, operates with thin stillage, a residue from bio-ethanol fermentation, as the main feedstock. Thin stillage is energy-rich due to its high protein content, but due to its high nitrogen and sulphate content is a somewhat complicated feedstock. The high nitrogen concentration results in inhibition of the microbial process and also selects for nitrogen-tolerant, but slow-growing, syntrophic acetate-oxidising bacteria (SAOB). The high sulphate concentration in the feedstock results in production of toxic and inhibitory sulphides through the activity of sulphate-reducing bacteria (SRB). Measures currently applied at Norrköping biogas plant to optimise the degradation of thin stillage include: i) use of mesophilic temperature and addition of hydrochloric acid, ii) use of long hydraulic retention time and iii) addition of iron and trace elements.

This thesis investigated how to obtain a more efficient biogas process treating thin stillage, with Norrköping biogas plant as the model plant. It also explored the role of SRB in the anaerobic process at high nitrogen content and sought to identify optimal conditions for ammonia-tolerant methane-producing microorganisms. This was done by measuring SRB abundance in several large-scale biogas processes to identify conditions resulting in reduced numbers. In parallel, the effects of increasing temperature and organic load, calcium addition and a two-stage strategy were evaluated in laboratory studies. The results showed a correlation between high ammonia level and temperature with decreased abundance of SRB, but none of the operating strategies tested proved successful in repressing sulphate reduction. However, increasing ammonia and/or organic loading rate influenced both the acetogenic and methanogenic community, including potential SAOB. Moreover, increasing the temperature to 44 ºC resulted in increased abundance of thermotolerant SAOB and their partner methanogen and higher biogas yield (+22%). A maximum ammonia threshold concentration of approximately 1.1 g L-1 was identified.

Application of the findings reported in this thesis has resulted in increased process stability in biogas plants in Sweden.

Authors/Creators:Moestedt, Jan
Title:Biogas production from thin stillage
Subtitle:exploring the microbial response to sulphate and ammonia
Series Name/Journal:Acta Universitatis Agriculturae Sueciae
Year of publishing :2015
Depositing date:20 January 2015
Number of Pages:58
I.Moestedt, J., Nordell, E., Nilsson Påledal, S. (2013). Biogas production from thin stillage on an industrial scale – experience and optimisation Energies 6 (11), 5642-5655
II.Moestedt, J., Nilsson Påledal, S., Schnürer, A. (2013). The effect of substrate and operational parameters on the abundance of sulphate-reducing bacteria in industrial anaerobic digesters. Bioresource Technology 132, 327-332.
III.Moestedt, J., Nordell, E., Schnürer, A. (2014). Comparison of operational strategies for increased biogas production from thin stillage. Journal of Biotechnology 175 (1), 22-30.
IV.Moestedt, J., Müller, B., Westerholm, M., Schnürer, A. (2015). Ammonia threshold for inhibition of anaerobic digestion of thin stillage independently of loading rate and responses in the methanogenic and acetogenic community (submitted)
V.Moestedt, J., Nordell, E., Hallin, S., Schnürer, A. (2015). Attempts to separate sulphide and methane production with two-stage anaerobic digestion for industrial application (submitted)
Place of Publication:Uppsala
Publisher:Department of Microbiology, Swedish University of Agricultural Sciences
ISBN for printed version:978-91-576-8218-5
ISBN for electronic version:978-91-576-8219-2
Publication Type:Doctoral thesis
Full Text Status:Public
Agris subject categories.:P Natural resources > P06 Renewable energy resources
P Natural resources > P10 Water resources and management
Q Food science > Q70 Processing of agricultural wastes
Subjects:(A) Swedish standard research categories 2011 > 1 Natural sciences > 106 Biological Sciences (Medical to be 3 and Agricultural to be 4) > Biochemistry and Molecular Biology
(A) Swedish standard research categories 2011 > 1 Natural sciences > 106 Biological Sciences (Medical to be 3 and Agricultural to be 4) > Microbiology (Microbiology in the medical area to be 30109)
(A) Swedish standard research categories 2011 > 2 Engineering and Technology > 209 Industrial Biotechnology > Bioprocess Technology
(A) Swedish standard research categories 2011 > 2 Engineering and Technology > 209 Industrial Biotechnology > Bioenergy
Agrovoc terms:biogas, brewery byproducts, wastewater treatment, anaerobic digestion, sulphate, sulphides, bacteria, methanogens, reduction
Keywords:anaerobic digestion, biogas, sulphate, sulphate-reducing bacteria, acetogens, methanogens, syntrophic acetate-oxidising bacteria, hydrogen sulphide, thin stillage, ammonia inhibition
Permanent URL:
ID Code:11751
Faculty:NJ - Fakulteten för naturresurser och jordbruksvetenskap
Department:(NL, NJ) > Dept. of Microbiology (until 161231)
External funders:FORMAS
Deposited By: Jan Moestedt
Deposited On:21 Jan 2015 10:41
Metadata Last Modified:10 Sep 2020 13:41

Repository Staff Only: item control page


Downloads per year (since September 2012)

View more statistics