Department of Crop and Soil Sciences, Cornell University, Ithaca, NY 14853, USA.
Bioresour Technol. 2012 Jun;114:644-53. doi: 10.1016/j.biortech.2012.03.022. Epub 2012 Mar 21.
Biochars (n=94) were found to have ash contents from 0.4% to 88.2%, volatile matter from 13.2% to 70.0%, and fixed carbon from 0% to 77.4% (w/w). Greater pyrolysis temperature for low-ash biochars increased fixed carbon, but decreased it for biochars with more than 20% ash. Nitrogen recovery varied depending on feedstock used to a greater extent (12-68%) than organic (25-45%) or total C (41-76%) at a pyrolysis temperature of 600 °C. Fixed carbon production ranged from no enrichment in poultry biochar to a 10-fold increase in corn biochar (at 600 °C). Prediction of biochar stability was improved by a combination of volatile matter and H:C ratios corrected for inorganic C. In contrast to stability, agronomic utility of biochars is not an absolute value, as it needs to meet local soil constraints. Woody feedstock demonstrated the greatest versatility with pH values ranging from 4 to 9.
生物炭（n=94）的灰分含量为 0.4%至 88.2%，挥发分含量为 13.2%至 70.0%，固定碳含量为 0%至 77.4%（w/w）。较低灰分生物炭的较高热解温度会增加固定碳，但对于灰分超过 20%的生物炭则会降低固定碳。在 600°C 的热解温度下，氮的回收率取决于所用的原料，受影响的程度大于有机（25-45%）或总碳（41-76%）（12-68%）。固定碳的产量从家禽生物炭的无富集到玉米生物炭的 10 倍增加（在 600°C 下）。通过对无机碳进行修正的挥发分和 H:C 比的组合，提高了生物炭稳定性的预测。与稳定性不同，生物炭的农业利用价值不是一个绝对的值，因为它需要满足当地土壤的限制。木质原料表现出最大的多功能性，pH 值范围从 4 到 9。
