为减弱天然气吸附(ANG)存储过程中的热效应,采取提高吸附剂热导率的技术路线,通过采用正交试验设计法,研制活性炭和膨胀石墨复合吸附剂,并由储罐吸附床典型部位在充放气过程的温度变化,校验复合材料的有效性。结果表明,活性炭比表面积为2074m2/g时,选择活性炭与膨胀石墨质量混合比例1:1、膨胀石墨制备时间30s、制备温度600℃、成型压力9MPa时制备复合吸附剂的热导率最大。设计容积为1385mL的扁平形储罐,在充放气速率为15L/min,最大充气压力为3.5MPa条件下,吸附床填充复合吸附剂时,储罐中心温度波动将减少约12℃,应用活性炭一膨胀石墨复合吸附剂能减弱吸附热效应。
In order to weaken the thermal effect in the process of ANG storage, heat transfer enhance- ment of the storage system was reinforced by improving the thermal conductivity of carbon based adsorbent via compositing with expanded graphite. Orthogonal design was carried out to study the influence of the values of process parameters on the thermal conductivity of the composite adsorbent developed by activated carbon and expanded graphite. The efficiency of the measure was verified by charge and discharge tests under the flow rate of methane 15 L/min on a conformable tank respectively filled with activated carbon and composite adsor- bent. It shows that, while the activated carbon in specific surface area 2074 m2/g was selected, the thermal conductivity of the composite obtained the maximum where the mixing ratio between activated carbon and ex- pandable graphite, heating temperature, heating duration and consolidating pressure is respectively set as 1: 1, 600 ℃, 30 s and 9 MPa. Results also reveal that, during the charge and discharge process undertaken at pressure 3.5 MPa and flow rate 15 L/min, in comparing with where the conformable tank whose volume was 1385 mL is filled with the activated carbon, packing with the composite adsorbent can weaken the temper- ature fluctuation at the central region of the conformable tank for about 12 ℃. Conclusions are drawn that ap- plication of composite adsorbent formed by activated carbon and expanded graphite is feasible for effectively managing the thermal effect of ANG.