Performance study of compounded biocover material for methane removal based on cattle manure compost

ABSTRACT

Methane is the second most significant greenhouse gas. Landfill cover soils play an important role in mitigation of methane emission from critical sources – Landfills. In this study, methane removal biocover materials based on cattle manure compost (CMC) were constructed and its performance was investigated. When comparing CH₄ removal abilities of sand (S), clay soil (CS), paddy soil (PS) and CMC, CMC was the most effective biocover material for the reduction of methane emission. The maximum removal rate (V_max) and half saturation constant (K_m) of CMC peaked at 3451.25 ± 18.57 μg g⁻¹ h⁻¹ and 3.67 ± 0.02 × 10⁵ ppm, respectively, which are higher than those in previous studies. Thereafter, three compounded biocover materials (CBMs) were established based on the mixture of CMC and other three materials (ratio of 2:8). The rate of the three CBMs was enhanced by 13.56, 13.27 and 16.42 times, respectively, more than the S, CS and PS by adding CMC. Saturated water content of 80% and 35°C were found to be the optimum moisture and temperature, respectively, for CBMs. Analysis of community diversity using terminal restriction fragment length polymorphism (T-RFLP) showed that the diversity and evenness indexes of the CBMs decreased after adding CMC; Type I methanotroph was the most dominated methanotroph in the CBMs. CMC not only influenced bacterial community but also improved nutrient and CH₄ removal capacity of CBMs. All results showed that CMC and CBMs could effectively remove CH₄, and the screening and construction of CBMs are important for decreasing CH₄ emission.

KEYWORDS:

• Methane mitigation emission
• methanotroph
• cattle manure compost
• compounded biocover material
• T-RFLP

Acknowledgements

The authors are grateful to the School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, China, for providing all the laboratory facilities. The authors thank Yongqing Qu for his friendly help with CMC.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 41275161]; Youth Fund of Shihezi University [grant number 2012RCZXJQ05].