The Characteristics of Carbon, Nitrogen and Sulfur Transformation During Cattle Manure Composting-Based on Different Aeration Strategies.

Yue Wang,Guoyuan Zou,Hongmin Dong,Xinrong Li,Shanjiang Liu,He Guo,Wentao Xue,Tongke Zhao

doi:10.3390/ijerph16203930

Abstract

This study aimed to investigate the characteristics of gaseous emission (methane—CH4, carbon dioxide—CO2, nitrous oxide—N2O, nitric oxide—NO, hydrogen sulfide—H2S and sulfur dioxide—SO2) and the conservation of carbon (C), nitrogen (N), and sulfur (S) during cattle manure composting under different aeration strategies. Three aeration strategies were set as C60, C100, and I60, representing the different combinations of aeration method (continuous—C or intermittent—I) and aeration rate (60 or 100 L·min−1·m−3). Results showed that C, N, S mass was reduced by 48.8–53.1%, 29.8–35.9% and 19.6–21.9%, respectively, after the composing process. Among the three strategies, the intermittent aeration treatment I60 obtained the highest N2O emissions, resulting in the highest N loss and greenhouse gas (GHG) emissions when the GHG emissions from power consumption were not considered. Within two continuous aeration treatments, lower aeration rates in C60 caused lower CO2, N2O, NO, and SO2 emissions but higher CH4 emissions than those from C100. Meanwhile, C and N losses were also lowest in the C60 treatment. H2S emission was not detected because of the more alkaline pH of the compost material. Thus, C60 can be recommended for cattle manure composting because of its nutrient conservation and mitigation of major gas and GHG emissions.

Highlights

The rapid development of China’s livestock industry has increased the generation of animal manure
The temperature of composting pile increased with the decomposition of available organic materials by indigenous microorganisms which produced energy [32]
NO3 − -N in aerobic zones may move to anaerobic zones by diffusion or mass flow, and NO3 − -N was denitrified to nitrous oxide (N2 O) and N2 in the anaerobic zones

Summary

Introduction

The rapid development of China’s livestock industry has increased the generation of animal manure. Livestock manure in China has reached an annual volume of 3.8 billion tons [1]. 40% of manure has not been used properly because of the long-term separation of animal breeding and manure land application, which results in severe pollution and a significant loss of nutrient resources [1]. It’s estimated that the nutrient losses have reached 3 million tons and greenhouse gas (GHG) emissions have exceeded 100 million tons of CO2 equivalent (CO2 eq) per year because of unused manure and other organic agriculture waste [2,3]; and odor emanation has resulted in numerous complaints. Pollution prevention of livestock and poultry breeding has been a focus of the current agricultural work in China. Among the different manure treatments, composting is used as an alternative to traditional manure management and is widely adopted by the animal production

Objectives

Methods

Results

Conclusion