A review on the research advances in biochar from the organic solid waste pyrolysis
This paper intends to provide a general review over the advances in biochar from organic waste pyrolysis in recent years. As is known, the municipal solid waste(MSW) is not only the main source of environmental pollution, but also the unique ever-growing garbage resources today, so that the MSW can be taken as a big resource with a great exploration prospect in providing clean energy and helping to relieve the aggravating energy crisis. It is just for this reason that the current MSW-treating technology, such as landfill, aerobic composting and incineration, may yield to the new active and positive MSW treatment for energy reuse. Among them, the pyrolysis has received close attention to retrieving renewable oil, gas and biochar in the absence of oxygen, and less secondary pollution at that. Due to the rich nutrients(N, P, K), the characteristics of porous, large surface area and highly aromatic structure, biochar can be used as a fertilizer supplement in the agricultural production. Moreover, adding carbon to the soil, biochar is also found highly beneficial for recovering the fertility of the land soil and contribute significantly to carbon abatement, which accounts for the great prosperity of research. Besides, since temperature is the key parameter in pyrolysis treating, we have also introduced the effects of the final temperature and heating rate on the solid waste pyrolysis products, such as gases, bio-oils and biochars, which also account for the research tide in the pyrolysis characterization of the different raw materials, and pollutant emissions in the pyrolysis process. At the same time, we have also given a detailed discussion on the formulation conditions and the characteristic components of biochar, the biological and abiotic oxidation process in the soil, as well as the research trend about the benefits for the global climate change and sustainable soil conservation and so on. Thus, it can be concluded that the development of the organic waste pyrolysis biochar technology is highly promising for urban organic waste treatment. Therefore, we do believe it is necessary to encourage and promote the following research fields: (1) get the similar biochar produced from different mixed wastes; (2) control the pollutant in the process of waste pyrolysis; (3) the soil environmental behavior and benefits of the organic waste known as biochar.
environmental engineeringorganic solid wastepyrolysisbiocharsequestration/release of carbonsoil