Elsevier

Bioresource Technology

Volume 297, February 2020, 122518
Bioresource Technology

Odor emission and microbial community succession during biogas residue composting covered with a molecular membrane

https://doi.org/10.1016/j.biortech.2019.122518Get rights and content

Highlights

  • NH3 and H2S emission decreased by 58.64% and 38.13% in the CT group.

  • TN, NH4+-N, and NO3-N contents were higher in the CT group.

  • Pseudomonas and Bacillus in the CT group were lower than those in the CK group.

  • The dominated SRB-Desulfovibrio in the CT group was higher than that in the CK group.

Abstract

A membrane-covered composting system was used to investigate the odor emission and microbial community succession during biogas residue composting. Results showed that in comparison with the control (CK) group, the NH3 and H2S emissions outside the membrane of the membrane-covered (CT) group decreased by 58.64% and 38.13%, respectively. The nitrogen preservation rate of the CT group was increased by 17.27% in comparison with the CK group. Moreover, the ammonium nitrogen and nitrate nitrogen contents of the CT group were 37.68% and 11.77% higher than those of the CK group, respectively. Microbial analysis showed that the average abundance and co-occurrence rate of ammonification bacteria dominated by Pseudomonas and Bacillus in the CT group were lower than those in the CK group, and the abundance of anaerobic sulfate-reducing bacteria (SRB) dominated by Desulfovibrio in the CT group was higher than that in the CK group.

Introduction

In China, the amount of livestock and poultry manure has reached 3.8 billion tons every year (Wang et al., 2017). Anaerobic digestion is an environmentally sustainable technique that can be used to treat livestock manure. The biogas residue produced by anaerobic digestion after solid–liquid separation is rich in organic matter (OM), nitrogen, phosphorus, potassium, and other nutrients (Tambone et al., 2010). However, the characteristic of biogas residue differs significantly from fresh organic solid waste, with most of the organic matter being partially stabilized and more nitrogen in the form of NH4+-N. Meanwhile, direct application of biogas residue without composting causes damage to the plant (Abubaker et al., 2012). Many researchers have found that composting not only can degrade organic pollutants, such as antibiotics and hormones but also reduce the bioavailability of heavy metals (Singh and Kalamdhad, 2012). Previous studies have demonstrated that increasing the temperature of compost can accelerate the humification process and shorten the fermentation period (Yamada et al., 2007). Moreover, high temperature can also kill pathogens and weed seeds in compost and enable the fertilizer to reach the harmless standard.

However, a large amount of malodorous gases are often released during composting, and the main components of odor are ammonia (NH3), hydrogen sulfide (H2S), and volatile organic compounds. Previous studies have shown that ammonia is the main component of odor in compost (Kithome et al., 1999). The main measures for odor control in composting include adding additives, biological deodorization, and covering treatment (Ding et al., 2019). Some commonly used additives include zeolite, biochar, bentonite, and superphosphate. Awasthi et al. (2017) reported that biochar addition could significantly reduce NH3 emission by 58.03%–65.17%. Yuan et al. (2018) found that adding superphosphate and dicyandiamide can reduce NH3 emission by 12.3%. The main processes of biological deodorization are including biological filtration, biological washing, and biological drip filtration method. Among them, the removal rate of NH3 by biological filtration method was the highest (Busca and Pistarino, 2003), generally at 95% to 98%. Studies on odor treatment by membrane covering are relatively few. Sun et al. (2018) studied the membrane-covered aerobic composting and analyzed NH3 emissions, the results showed that the NH3 emissions decreased by 20%-30%, because the water film formed under the membrane could absorb ammonia and return them to the compost pile. The membrane covering treatment changes a series of physical and chemical indicators in the compost pile, which affects the growth activities of the bacteria in the compost. Moreover, microbial activity plays a key role in the OM transformation in the compost. Ammonification bacteria affect the ammonia emission in the compost, denitrifying bacteria are most active in the thermophilic phase, and nitrifying bacteria generally begin to increase in the maturation phase of the compost. These microorganisms are sensitive to environmental changes (Ma et al., 2018). Nevertheless, little information has been reported about odor emission and microbial community succession in the molecular membrane composting system.

In this experiment, a functional molecular membrane was used as covering material, a forced ventilation system was utilized to supply oxygen, a comparative treatment of covering and non-covering composting system was set up, and the changes of microbial flora in the fermentation process of the two compost piles were combined to study the effect of membrane covered system on odor emission reduction during composting.

Section snippets

Membrane-covered composting system

A membrane-covered forced ventilation composting system was used in the experiments at the composting plant of Nanjing Tech University. The critical feature of the semi-permeable membrane was divided into three layers, where the middle layer was composed of ePTFE, and the pore size was 0.2 μm and the inner and outer layers were made of polyester membrane with anti-ultraviolet and anti-corrosion characteristics. The membrane had the functions of being waterproof, windproof, and permeable to

Physical and chemical properties of compost

Temperature is the key index of microbial activity in the composting process (Külcü and Yaldiz, 2014). The temperature of the two compost piles rose rapidly to above 50 °C within 7–9 days (Fig. 1A). In the thermophilic phase, the highest temperatures of CT and CK groups reached 54.25 °C and 53.75 °C, respectively, and maintained for 24 and 22 days. The rapid increase in temperature promoted the release of heat from microbial respiration and the rapid degradation of OM (Bernal et al., 2009).

Conclusion

Membrane-covered composting system effectively preserved the nitrogen and reduced the release of odor during composting. The nitrogen preservation rate of the CT group was increased by 17.27% compared with the control. The NH3 and H2S emission decreased by 58.64% and 38.13% in the CT group compared with the control. Microbial analysis showed that the average abundance and co-occurrence rate of ammonification bacteria dominated by Pseudomonas and Bacillus in the CT group were lower than those in

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

This work was supported by the National Key Research and Development Program of China (2018YFD1100603, 2016YFE0112800), the Key Research and Development Technology of Ningxia Hui Autonomous Region (2019BFH02008), the National Natural Science Foundation of China (21777069), and the Jiangsu Synergetic Innovation Center for Advanced Bio-Manufacture (XTE1832).

References (44)

  • R. Külcü et al.

    The composting of agricultural wastes and the new parameter for the assessment of the process

    Ecol. Eng.

    (2014)
  • M. Koyama et al.

    Effect of temperature on thermophilic composting of aquaculture sludge: NH3 recovery, nitrogen mass balance, and microbial community dynamics

    Bioresour. Technol.

    (2018)
  • L. Li et al.

    Anaerobic oxidation of methane coupled to sulfate reduction: Consortium characteristics and application in co-removal of H2S and methane

    J. Environ. Sci.

    (2019)
  • S.S. Ma et al.

    Bacterial community succession during pig manure and wheat straw aerobic composting covered with a semi-permeable membrane under slight positive pressure

    Bioresour. Technol.

    (2018)
  • R. Riffaldi et al.

    Water extracts of fresh and mature farmyard manure

    Biol. Wastes

    (1988)
  • J. Schmidtova et al.

    Correlation of bacterial communities supported by different organic materials with sulfate reduction in metal-rich landfill leachate

    Water Res.

    (2011)
  • J. Singh et al.

    Concentration and speciation of heavy metals during water hyacinth composting

    Bioresour. Technol.

    (2012)
  • X.X. Sun et al.

    The effect of a semi-permeable membrane-covered composting system on greenhouse gas and ammonia emissions in the Tibetan Plateau

    J. Cleaner Prod.

    (2018)
  • Y. Sun et al.

    Assessing key microbial communities determining nitrogen transformation in composting of cow manure using illumina high-throughput sequencing

    Waste Manage.

    (2019)
  • F. Tambone et al.

    Assessing amendment and fertilizing properties of digestates from anaerobic digestion through a comparative study with digested sludge and compost

    Chemosphere

    (2010)
  • C. Trois et al.

    Effect of pine bark and compost on the biological denitrification process of non-hazardous landfill leachate: Focus on the microbiology

    J. Hazard. Mater.

    (2010)
  • C. Wang et al.

    Metagenomic analysis of microbial consortia enriched from compost: new insights into the role of Actinobacteria in lignocellulose decomposition

    Biotechnol. Biofuels

    (2016)
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