[Objective]In order to reduce the energy consumption and reaction time of hydrothermal carbonization, design and developa pre pressurized hydrothermal carbonization process.[ Method] Using straw as raw material, the effects of pressurized medium and pressure on the time-consuming, power consumption were investigated by FT-IR, XRD, BET, and adsorption properties of carbon products on methylene blue also were be monitored.[Reslut]The results showed that the heating time can be shortened to 63.917% after pre-pressurizing air or helium heating rate increased by 2.772 times, and the electrical heating efficiency can be increased by 1.657 times, whereas has no remarkable effect on the surface functional groups of biochar product and crystalline phase structure .The rising of initial pressure increases the substrate concen-tration, causing the occurrence of polymerization in advance.Helium was more favorable to shorten the hydrothermal reaction cycle than the air medium, but the energy saving efficiency and the surface functional group OH content of carbon products were slightly lower, which may be related to the concentration of oxygen in the hydrothermal reactor.The adsorption isotherm of the carbon products to methylene blue was in ac-cordance with the Freundlich model.The sample had a 1 /n ratio between 0.5 and 1.0, showing a preferential adsorption.[Conclusion]The research can provide scientific basis for developing and upgrading the hot water carbonization process.%[目的]为降低水热炭化的能耗及反应时间,设计开发预增压水热炭化工艺.[方法]以稻草为原料,通过FT-IR、XRD、BET等表征及对亚甲基蓝的吸附性能分析,研究增压介质和压力对水热炭化升温耗时、耗电以及对生物炭的影响规律.[结果]预增压后总升温时间最大可缩短63.917%,升温速率提高2.772倍,电加热效率提高1.657倍;水热反应体系的压力增加对炭产物表面官能团组成、产物晶相结构、表面积和吸附性能无显著影响,但可加快水热炭化进程,反应体系压力增加提高了体系中的底物浓度,从而使暴发聚合反应的饱和浓度提前出现;氦气比空气介质更有利于缩短水热反应周期,但节能效率及炭产物表面OH类官能团含量略低,可能与介质中氧浓度有关.所制炭对亚甲基蓝的吸附等温曲线符合Freundlich模型,样品的1/n在0.5~1.0,表现为优惠型吸附.[结论]该研究可为开发预增压水热炭化工艺提供科学依据.
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