Environmental impact and optimization suggestions of pig manure and wastewater treatment systems from a life cycle perspective

Binbin Liu; Hao Zhou; Lanfeng Li; Jing Ai; Hang He; Junxia Yu; Ping Li; Weijun Zhang

doi:10.1016/j.scitotenv.2023.167262

Environmental impact and optimization suggestions of pig manure and wastewater treatment systems from a life cycle perspective

Sci Total Environ. 2023 Dec 20:905:167262. doi: 10.1016/j.scitotenv.2023.167262. Epub 2023 Sep 21.

Authors

Binbin Liu¹, Hao Zhou¹, Lanfeng Li¹, Jing Ai², Hang He¹, Junxia Yu³, Ping Li¹, Weijun Zhang⁴

Affiliations

¹ School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China.
² School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China; Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia.
³ Key Laboratory of Novel Biomass-Based Environmental and Energy Materials in Petroleum and Chemical Industry, School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430074, China.
⁴ School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China; Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430074, Hubei, China; National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: zhangweijun@cug.edu.cn.

PMID: 37741414
DOI: 10.1016/j.scitotenv.2023.167262

Abstract

With the rapid development of the pig farming industry in China, a large amount of pig manure is inevitably generated. The management and utilization of pig manure in a sustainable approach require a systematic analysis of the environmental impacts generated from the existing pig manure treatment and disposal routes. In this study, three typical pig manure treatment and disposal routes: pig manure solid-liquid separation, i) wastewater biological treatment, direct land application of manure/sludge; ii) black-film anaerobic digestion of wastewater, mono-composting of manure/sludge and land use; iii) wastewater biological treatment, co-composting of manure/sludge and land use, were comparatively assessed in terms of their environmental impacts using the life cycle assessment. The results show that the added chemicals in wastewater treatment and the consumed electricity in composting the manure/sludge are the two main contributors to all environmental impacts. Thus, using green chemicals, controlling the dosage of added chemicals accurately, and selecting composting types with low energy consumption will significantly reduce the environmental burden of pig manure treatment and disposal routes. For the global warming potential of the evaluated three pig manure treatment and disposal routes, direct emissions of greenhouse gases during the composting process contribute the most, accounting for 77 %, 95 %, and 79 %, respectively. Furthermore, the struvite recovery with anaerobic digestion from pig manure will bring excellent environmental benefits, which will markedly offset the toxicity impacts and carbon emissions derived from pig manure treatment and disposal process. Overall, this work quantitatively evaluates the potential environmental impacts of the existing pig manure treatment and disposal routes, providing insights on optimization for future technical improvement and development.

Keywords: Aerobic composting; Anaerobic digestion; Environmental impact; Life cycle assessment; Pig manure treatment and disposal.

MeSH terms

Animals
Environment
Life Cycle Stages
Manure
Sewage
Swine
Wastewater*
Water Purification*

Substances

Wastewater
Sewage
Manure