Thermochemically converted biochar is considered as one of the promising alternative solid-fuel due to its high carbon contents of up to 80%, and has great potential to produce environmentally-friendly green-energy by improved fuel properties and emission-reduction of potentially toxic elements (PTEs). In this study, the biochar fuels, produced from peanut shell (PS) and wheat straw (WS) at 300, 500 and 700 °C, alone and blended with coal at mass ratio of 20% and 50% were systematically investigated for combustion characteristics and their potential to reduce the emission of PTEs including As, B, Ba, Be, Bi, Cd, Co, Cr, Cu, Ga, Ni, Pb, Sb, Sn, V and Zn in relation to partitioning, retention and volatilization in the co-combustion systems, using a variety of experimental techniques. Results indicated that the biochar-coal blended fuels in equal proportion showed steady state combustion over broad temperature range resulting increased the combustion efficiency and improved the thermal characteristics in comparison to coal and/or biomass-coal fuels. In addition, soot yield, CO emission and un-burned carbon in fly ash reduced significantly in biochar-blended fuels. However, CO₂ emission from biochar-coal co-combustion was comparable to coal and/or biomass-coal fuels. Moreover, the present study illustrated that the volatilization potential of PTEs during combustion of biochar and their blends with coal decreased considerably up to 21% compared to that of coal, and enrichment of these contaminants occurred in the bottom and fly ashes ranged from 15.38–65% and 24.54–74.29%, respectively. Slagging and fouling problems were still found with biochar-coal co-combustion due to the higher inorganic fraction of biochar, which were overcome with the hydrothermal washing of fuels. Thus, it can be concluded that biochar-coal co-combustion is a suitable option for its use in existing coal-fired energy generation system to achieve the sustainable clean-green energy and reduction of gaseous PTEs emission.

由于热化学转化的生物炭具有高达80％的高碳含量，因此被认为是有前途的替代固体燃料之一，并且具有通过改善燃料特性和减少潜在有毒元素的排放而产生环保绿色能源的巨大潜力。 （PTE）。在这项研究中，系统地研究了分别在300、500和700°C下由花生壳（PS）和麦秸（WS）制成并与煤混合的质量比为20％和50％的生物炭燃料的燃烧特性。以及它们与PTE的分配，保留和挥发有关的减少PTE排放的潜力，包括As，B，Ba，Be，Bi，Cd，Co，Cr，Cu，Ga，Ni，Pb，Sb，Sn，V和Zn共燃烧系统，使用各种实验技术。结果表明，与煤和/或生物质燃料相比，等比例的生物炭-煤混合燃料在较宽的温度范围内表现出稳态燃烧，从而提高了燃烧效率并改善了热特性。此外，在生物炭混合燃料中，粉煤灰的烟灰收率，CO排放和未燃烧的碳显着降低。但是，CO₂生物炭-煤共燃烧产生的排放与煤炭和/或生物质-煤燃料相当。此外，本研究表明，与煤相比，生物炭及其与煤的混合物燃烧过程中，PTE的挥发潜能下降了多达21％，并且这些污染物的富集发生在底部和粉煤灰中，范围为15.38-65。 ％和24.54–74.29％，分别。由于生物炭中无机物含量较高，生物炭与煤的共燃烧仍然存在结渣和结垢的问题，这些问题可通过燃料的水热洗涤得以克服。因此，可以得出结论，生物炭-煤共燃烧是在现有的燃煤发电系统中使用的合适选择，以实现可持续的清洁绿色能源并减少气态PTE的排放。