Biochar produced from mineral salt-impregnated chicken manure: Fertility properties and potential for carbon sequestration

Ran Xiao; Jim J Wang; Lewis A Gaston; Baoyue Zhou; Jong-Hwan Park; Ronghua Li; Syam K Dodla; Zengqiang Zhang

doi:10.1016/j.wasman.2018.06.047

Biochar produced from mineral salt-impregnated chicken manure: Fertility properties and potential for carbon sequestration

Waste Manag. 2018 Aug:78:802-810. doi: 10.1016/j.wasman.2018.06.047. Epub 2018 Jul 4.

Authors

Ran Xiao¹, Jim J Wang², Lewis A Gaston³, Baoyue Zhou³, Jong-Hwan Park³, Ronghua Li⁴, Syam K Dodla⁵, Zengqiang Zhang⁶

Affiliations

¹ College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.
² School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA. Electronic address: jjwang@agcenter.lsu.edu.
³ School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA.
⁴ College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China.
⁵ Red River Research Station, Louisiana State University Agricultural Center, Bossier City, LA 71112, USA.
⁶ College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China. Electronic address: zqzhang@nwafu.edu.cn.

PMID: 32559975
DOI: 10.1016/j.wasman.2018.06.047

Abstract

In this study, nutrient properties and carbon sequestration potential of biochars derived from chicken manure (CM) impregnated with mineral salts (calcium chloride, magnesium chloride, ferric chloride) were evaluated. Pretreatment with mineral salts reduced phosphorus (P) availability via the formation of insoluble metal phosphate minerals. Less carbon was lost during the pyrolysis of pretreated CM, and the produced biochars (BC_Ca, BC_Mg, and BC_Fe) were more stable (i.e., reduced C loss during chemical oxidation and less CO₂ release during incubation) than pristine biochars. Spectroscopic evidence indicated that enhanced biochar stability via metal salt pretreatment before pyrolysis was related to increased aromatization and enhanced physical protection due to the metal-oxygen interaction, together with the formation of metal mineral phases on biochar surfaces. Moreover, ferric chloride was the optimal additive, as it significantly decreased biochar P leachability and increased carbon sequestration potential.

Keywords: Biochar; Chicken manure; Mineral salts impregnation; Nutrient recycling; Pyrolysis temperature.