Adsorption Performance Study Of Ellipsoid Biomass Adsorbent

With the increasingly exhausted of the world’s fossil energy, the new energy is developmenting constantly, In the last century Sixties and seventies anhydrous ethanol has entered people’s field of vision The ordinary distillation system can raise the ethanol concentration from a low level to 95%, but while the concentration of ethanol and water solution up to 92%, the energy consumption of Production will increase significantly, greatly increased the cost of production, and there is a exists azeotropic point when the ethanol concentration up to 95.57%, the common distillation system unable to get a higher ethanol concentration. The traditional industrial production method of anhydrous ethanol, such as azeotropic distillation, extractive distillation, membrane separation and molecular sieve adsorption and biomass adsorption, all associated with high energy consumption and high pollution. In recent years, the experimental study on the preparation of anhydrous ethanol by the Biomass adsorption method has become a hot topic in the domestic, and the practice proved that it is a low cost and little pollution method.The experiment studied the adsorbent fluid mechanics performance of fixed bed firstly. The diameter of adsorption tower is 50 mm,100mm and 200 mm, the effective loading height is 3 m, the particle size of adsorbent is 3.25 mm, 3.25 mm, 5.09 mm and 6.43 mm; measured the loading density and void ratio of the different size of adsorbent; In the process of experiment we make the air through the adsorbent bed From the top to bottom, there are six pressure measuring evenly distributed on the side of the absorption tower to collect the experimental data. obtained the relationship of bed unit pressure drop and air average velocity; simplified the complicated fixed bed for a thin tube parallel model; at last we get the relation formula between the flow coefficient of friction and the air Reynolds number. Then we studied the adsorption performance of the ellipsoid biomass adsorbent in fixed bed. The diameter of adsorption tower is 100 mm, the effective loading height is 3 m; The experiment mainly studied the different factors to the adsorption performance influence, such as feeding rate, adsorbent particle size and the bed height, measured the adsorption breakthrough curve, bed temperature curve and bed pressure drop curves in the process of regeneration. Calculated the fixed bed adsorption isotherm and the mass transfer coefficient of the adsorption process.The results showed that the concentration of alcohol and water steam can be improved from 95% to above 99.5% after adsorption of the adsorbent bed. In the process of adsorption, the highest temperature of adsorbent bed can reach 129 ℃, The temperature of the adsorbent bed is after rising first down, shows that adsorption process is exothermic process, so we can use the waste heat of adsorption tower to regenerate the adsorbent in order to reduce the stripping time. The adsorption performance of 5.09 mm Particle size adsorbent is best, the production of anhydrous ethanol is biggest in the same conditions; experimental data shows that The lower the steam feed rate the more production of anhydrous ethanol, but if the steam feed rate is too low the strength of the production would decrease, is not conducive to large-scale industrial application; the too large steam feed rate would lower the adsorbent efficiency, lead the production of anhydrous ethanol reduce. At last we determined the minimum loading height calculation formula of fixed bed adsorbent Under the experimental conditions by calculating the experimental data, it will be a certain help and guidance significance to the industrial production.