Exploring the Benefits of Biochar: A Review of Production Methods, Characteristics, and Applications in Soil Health and Environment

Document Type : Review papers


1 Institute of Agriculture and Animal Science, Paklihawa Campus, Tribhuvan University, Nepal

2 USDA-ARS, Grassland Soil and Water Research Laboratory, Temple, TX 76502, USA


Biochar is a carbon-rich solid by-product formed by treating biomass to high temperatures in an oxygen-deprived environment. It has recently increased in popularity due to its positive impacts on soils and climate change mitigation among others. Four production processes of biochar have been described in this review; Pyrolysis, Hydrothermal carbonization, Torrefaction, and Gasification. These processes differ in their temperatures, heating rates, usable feedstock, reaction environment, and complexity, ultimately determining the characteristics of biochar produced and their usage. Along with biochar, other products such as bio-oil and syngas are produced in different quantities. The quantities and qualities of these products are based on the temperature of the production process and the type of feedstock utilized respectively. Biochar usage includes and is not limited to soil management, organic waste management, water purification, greenhouse gas emission mitigation, carbon sequestration, fuel alternative, and land reclamation. This review finds biochar extremely important in climate-smart agriculture, mitigating global warming, and contributing a small part to fulfilling global energy needs. The gap in research regarding the effect of biochar from different feedstock needs to be filled, along with the standardization of production methods and application of biochar in various fields to increase the benefits while decreasing the harmful effects on the environment and human health. The research gap can be used as a guide to direct further research on biochar. The production of biochar is seen to have an upward trend, but its adoption by people in agriculture or land management is hindered by the economics surrounding it. Biochar can be an 'environmental savior' but proper policy-making and widespread research and extension must accompany its production.


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