A New Green Model for the Bioremediation and Resource Utilization of Livestock Wastewater.

Linhe Sun,Huijun Zhao,Dongrui Yao,Bei Li,Yajun Chang,Jixiang Liu

doi:10.3390/ijerph18168634

Abstract

The rapid growth of the livestock and poultry industries has resulted in the production of a large amount of wastewater, and the treatment of this wastewater requires sustainable and environmentally friendly approaches such as phytoremediation. A substrate-free floating wetland planted with water dropwort (Oenanthe javanica), a common vegetable in Southeast China, was constructed to purify a lagoon with anaerobically and aerobically treated swine wastewater in Suqian, China. The average removal rates of total nitrogen, ammonium nitrogen, nitrite nitrogen, and chemical oxygen demand were 79.96%, 95.04%, 86.14%, and 59.91%, respectively, after 40 days of treatment. A total of 98.18 g∙m−2 nitrogen and 19.84 g∙m−2 phosphorus were absorbed into plants per harvest through the rapid growth of water dropwort biomass, and the nitrogen accumulation ability was similar to that observed of other plants, such as water hyacinth. In addition, the edible part of water dropwort was shown to comply with the Chinese National Food Sanitation Standards and be safe for human consumption. Its low soluble sugar content also makes it a suitable addition to the daily diet. Overall, substrate-free floating constructed wetlands planted with water dropwort could be more widely used for livestock wastewater purification and could be integrated with plant–livestock production in China because of its high removal efficiency and recycling utilization of water dropwort biomass.

Highlights

The environmental pollution associated with the rapid development of livestock and poultry-breeding farms has become increasingly severe in China, and this greatly impedes the sustainable development of the livestock and poultry breeding industry
The Livestock wastewater (LW) used in this study was anaerobically and aerobically treated swine wastewater obtained from a swine farm in Suqian City, Jiangsu Province, China, and poured into a square 100 m2 lagoon 80 cm in depth that was seepage-proofed using an HDPE membrane situated around and at the bottom of the lagoon
A substrate-free floating constructed wetland planted with water dropwort could efficiently remove N (79.96%) and chemical oxygen demand (COD) (59.91%) from LW

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. China has been the world’s largest livestock and poultry producer since the early. 1990s, and livestock and poultry production has continually increased given the rapidly growing demand for animal products [1,2]. The environmental pollution associated with the rapid development of livestock and poultry-breeding farms has become increasingly severe in China, and this greatly impedes the sustainable development of the livestock and poultry breeding industry.

Methods

Results

Discussion

Conclusion