Primary Study On Slurry Reactor In Cold State For DME Synthesis

In 21centry,China faces challenges in energy supply,especially the liquid fuels. as a new kind of fuels,that the synthesis of dimethyl ether from biomss syngas is a very important way to overcome the challenges.Therefore, the cold state of the slurry reactor is studied for reaching after better mixing state .That liquid paraffine into which nitrogen is introduced from the bottom of the reactor is the investigating object. The special mixing state of gas and liquid is measured through optical difference, and the mixing time is measured through optical difference too. Various factors that influence the mixing time is investigated. The greater the gas flow into the system, the shorter the mixing time; when the gas flow reaches some higher extent, the influence is slight. Under the condition of the same rotation speed and the same gas flow, the mixing time expensed to reach the special mixing state are obviously different when using different oars. The rank of mixing time of four types of oars is given. The mixing time of big round six-vane turbine is the shortest in the mixing times of twelve oars. Substituting three-baffles with four-baffles, the mixing time is getting a little shorter. The heat and mass transfer in agitation tank are influenced significantly by the center big vortex. Research object is the system of liquid paraffin into which nitrogen gas entering.The influence of several important factors to the depth of vortex are studied through variable controlling method. They are oar shape, rotate speed, the depth of the baffle under liquid surface and gas flux introduced into liquid. The experiment indicated that (1) The round turbine with six vanes arose the deepest vortex. (2)As the baffles plug into the liquid slowly , the depth of vortex decreases; when the baffle pass by the oars, the depth of vortex decreases greatly. (3)The bigger the gas flux entering into liquid, the less deeper the vortex. The result of the experiment and the mechanism of factors mentioned above impacting on the depth of vortex are analyzed in the paper.The gas holdup is an important parameter for idicating the mixing state, however, in the case of the same gas holdup, the cubage of the air bubble is different, and the mixing state is different. In order to find a better way to measure the mixing state, the escaping time is investigated in this paper. the primary experiment suggest that the well mixing state cause the longer escaping time. Therefore, the escaping time can be used to measure the extent of mixing state.Finaly ,The experiment of Airtightness and hydrostatic test were proceed for the system. the process test plan was given in this paper.