Characterization of biochar as a carbon regulator in manure and environmental management applications

Biochar is a product of pyrolysis, which is the thermal decomposition of materials at elevated temperatures (300 - 900 °C) in an oxygen-limited atmosphere. Biochar has been recognized as a potentially vital tool to help reduce the climate change impact. It has been used in the agricultural sector as an addition to reduce greenhouse gas emissions in several animal husbandry settings. The application in the animal sector is an important point to reduce the overall amount of greenhouse gases released as this sector produces many greenhouse gases. Though not in every case a reduction of emissions was the result of the addition of biochar. This study analysed five feedstocks (peat, peat fibre, fine urban green waste and two types of brewery waste) and the resulting biochars to evaluate how pyrolysis at various temperatures affects the properties of the resultant biochars and how those different properties influence the potential of biochars to adsorb emissions from manure. Increasing pyrolysis temperature has been noted to lead to a decrease in volatile matter content for all feedstocks used, whereas the surface area and the fixed carbon content of the resultant biochars were shown to lead to an increase. This suggests that higher production temperatures are optimal to produce more stable biochars, which makes biochars an excellent material to sequester carbon, but this comes at a cost in energy demand and environmental terms. The study has examined the application of the resultant biochars in the regulation of greenhouse gas emissions associated with piggery manure management and was able to demonstrate the optimal configurations of biochar type and production process in regulating associated GHG emissions from the manure used in this study, which came from Germany. In addition, the biochars were used and able to adsorb dissolved organics from water. The results found here broaden the knowledge about the characterisation of biochars, and their applications and can potentially be used to include more biochar applications into policy