Flushing control strategies to improve the stability of a biogas slurry drip irrigation system: Behavioral characteristics and mechanisms

Haitao Wang; Chuanjuan Wang; Jiandong Wang; Xuefeng Qiu; Shuji Wang; Guangyong Li

doi:10.1016/j.jenvman.2022.116792

Flushing control strategies to improve the stability of a biogas slurry drip irrigation system: Behavioral characteristics and mechanisms

J Environ Manage. 2023 Jan 15;326(Pt B):116792. doi: 10.1016/j.jenvman.2022.116792. Epub 2022 Nov 23.

Authors

Haitao Wang¹, Chuanjuan Wang², Jiandong Wang³, Xuefeng Qiu⁴, Shuji Wang⁵, Guangyong Li⁶

Affiliations

¹ Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; Key Laboratory of Low-carbon Green Agriculture in North China, Ministry of Agriculture and Rural Affairs P. R., Beijing, 100081, China; College of Water Resources and Civil Engineering, China Agricultural University, Beijing, 100083, China.
² Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; Key Laboratory of Low-carbon Green Agriculture in North China, Ministry of Agriculture and Rural Affairs P. R., Beijing, 100081, China.
³ Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; Key Laboratory of Low-carbon Green Agriculture in North China, Ministry of Agriculture and Rural Affairs P. R., Beijing, 100081, China. Electronic address: wangjiandong@caas.cn.
⁴ Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
⁵ Institute of Water Conservancy and Hydroelectric Power, Hebei University of Engineering, Handan, 056000, China.
⁶ College of Water Resources and Civil Engineering, China Agricultural University, Beijing, 100083, China. Electronic address: lgyl@cau.edu.cn.

PMID: 36435137
DOI: 10.1016/j.jenvman.2022.116792

Abstract

Biogas slurry drip irrigation can mitigate environmental pollution and reduce the use of chemical fertilizers to enable sustainable development. However, the stability of the biogas slurry drip irrigation system (BSDIS) is disrupted by emitter clogging; hence, it is essential to explore the flushing control strategy of BSDIS. By means of combining actual measurement and simulation, this study investigates the BSDIS stability based on the three technical parameters of the flushing control strategy. Appropriate flushing control strategies can improve system stability and cause spatial differences on the drip irrigation tape. Under various flushing control strategies, the system stability primarily undergoes delays, sensitivity, and ineffectiveness of flushing with time. Compared with the without flushing and emitter outlet downward-oriented treatment, the optimal flushing combination (the high frequency flushing + emitter outlet upward-oriented treatment) reduces the emitter clogging content by approximately 70.97% and increases system stability by 189.1%. In the internal hydrodynamics, the laying direction of emitters does not change the movement characteristics of water flow, although the clogging particles do not completely follow the water flow, with some particles settling owing to gravity, thereby clotting the emitters. When clogging occurs, the increase in flushing speed is conducive to the increase in turbulent kinetic energy on the inlet surface of the emitter, which facilitate the flushing of clogged substances. This study proposes optimal flushing strategy parameters along with a new management mode for the waste liquid represented by biogas slurry.

Keywords: Biogas slurry drip irrigation; Clogging substance; Emitter; Flushing control strategy; Hydrodynamics.

MeSH terms

Agricultural Irrigation
Biofuels*
Fertilizers* / analysis
Water

Substances

Biofuels
Fertilizers
Water