家用天然气活性炭吸附储存的试验研究

为开发适用于家庭环境的吸附式天然气（ANG）储罐，选择比表面积为2 074 m²/g的SAC-02椰壳活性炭作吸附剂和附设有U形换热管的钢制压力容器为储存容器，在室温及3.5 MPa条件下，比较了充放气体积流率以及U形管内引入冷却水或热水后对ANG储罐吸附床温度及充放气总量的影响。结果表明：充放气体积流率大于10 L/min时，再增大体积流率对ANG储罐中心温度的影响变小；在U形管内循环30 ℃的冷却水和60 ℃的热水可抑制ANG储罐中心区域的温度波动，同时也可提高总充放气量。对比试验结果发现，充放气体积流率增大，ANG储罐吸附床的温度波动幅度增大，但ANG储罐中心上升到温度幅值所需要的时间缩短；在相同的充放气体积流率时，冷却水或热水的引入不影响ANG储罐吸附床中心区域上升或下降到幅值的时间，也不影响有实际意义的充放气过程的持续时间；民用ANG储罐可采取自来水作为充放气过程中的冷却或加热介质。

An experimental study of domestic-use natural gas storage vessels with an activated carbon as an adsorbent

Comparative experiments were carried out for the development of domestic use adsorbed natural gas(ANG) storage vessels.A storage vessel with U-shaped heat exchanging pipe surrounding the central region of the adsorbent bed was specially designed,coconut shell activated carbon SAC-02 which has an average specific surface area of 2074 m2/g was selected as an adsorbent.The daily consumption amount of the natural gas in a typical family was measured and applied to set the flow rates of methane charging in or discharging from the storage system at ambient temperature under pressure 3.5 MPa.Comparisons of the temperature records and the total amount of charge and discharge were also made by circulating the water respectively at 30 and 60℃ within the U-shaped pipe.Results show that the variation rate of temperature within the central region of the storage vessel will drastically increase while the flow rate is over 10 L/min;the circulation of water is beneficial to weakening the fluctuation of the temperature of the adsorbent bed and increasing the total charge/discharge amount of methane.Results also reveal that a larger charge/discharge rate brings about a stronger fluctuation of the temperature within the adsorbent bed,but the process for the central region to reach the maximum/minimum temperature is shortened;at the same charging/discharging flow rates,the introduction of water for cooling or heating neither changes the process for the central region to reach the maximum/minimum temperature nor affects the continuing time of actual charging/discharging process.It is concluded that the tap water can be directly used as the cooling/heating medium to limit the thermal effect in domestic ANG storage vessels.