Effects of amino-modified biofilm carriers on biogas production in the anaerobic digestion of corn straw

ABSTRACT

This paper studied the property of three different biofilm carriers added into the anaerobic digestion systems, a granular activated carbon, a polyacrylonitrile, and a polyacrylonitrile modified with diethylenetriamine (PAN-NH₂). The PAN-NH₂ system kept the maximum biogas and methane production, which were 42.69% and 37.29% higher than the control system, respectively. The value of pH and chemical oxygen demand, the content of total solid and volatile solid, volatile fatty acids concentration, coenzyme F₄₂₀ concentration, and microbial community analysis were investigated during the anaerobic digestion process. The PAN-NH₂ system had the highest removal efficiency of the pollutants and regulated the pH of the system better than other systems. The result of high-throughput sequencing analysis showed that the addition of biofilm carriers and mediation with amino-groups adjusted system pH and improved biogas and CH₄ production by reducing the relative abundance of bacteria in the hydrolysis/acidogenesis stages. Methanosarcina gradually replaced other methanogens during the experimental runs and was the dominant methanogen at the end of the anaerobic digestion process.

GRAPHICAL ABSTRACT

KEYWORDS:

• Amino modified biofilm carrier
• anaerobic digestion
• corn straw
• biogas
• microbial community

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Key Research and Development Program of China [grant number 2016YFE0112800], the National Natural Science Foundation of China [grant number 21777069], the Key Science and Technology Project of Jiangsu Province [grant number BE2016389], the Jiangsu Synergetic Innovation Center for Advanced Bio-Manufacture, the Qing Lan Project of Jiangsu Universities, and the Six Talent Peaks Project in Jiangsu Province.