Two adsorption refrigeration working pairs of zeolite with water and ethanol were studied and the parameters of Dubinin-Astakhov model were regressed using the experimental data of equilibrium. The coefficient of hete...Two adsorption refrigeration working pairs of zeolite with water and ethanol were studied and the parameters of Dubinin-Astakhov model were regressed using the experimental data of equilibrium. The coefficient of heterogeneity varied from 1.305 to 1.52 for the zeolite-water pair and from 1.73 to 2.128 for zeolite-ethanol pair. The maximum adsorption capacity varied from 0.315 to 0.34 for zeolite-water and 0.23 to 0.28 for zeolite-ethanol, respectively. The results showed that the zeolite-water pair is suitable for solar energy cooling not only because of the high latent heat of vaporization of water but also because of the better equilibrium performance. On the other hand, zeolite-ethanol gives a high adsorption capacity at high regeneration tem-perature, which means it can be used in heat engine systems like buses and cars.展开更多
Controlling the biogas fermentation process is the key for maintaining stable operation of biogas system and increasing gas yield. Aiming at features of biogas fermentation process and difficulties of control, a pract...Controlling the biogas fermentation process is the key for maintaining stable operation of biogas system and increasing gas yield. Aiming at features of biogas fermentation process and difficulties of control, a practical control scheme is proposed combining the abundant experience of biogas experts. And it discussed the structural design and hardware configuration of the expert control system, established the database and role base, and designed the control strategy of production system inference. The design scheme with ZigBee and PDA technology as core is employed so as to solve problems of environmental factor detection and data transfer management. The test result shows that the deviation of temperature is controlled within ± 0.9℃, the deviation of pH is controlled within ±0.3, the deviation of oxidation-reduction potential is controlled within ±30mV, the deviation of gas production is controlled within ± 9mL and that of methane concentration is controlled within ±4.5%. This system is easily expandable and applicable to biogas engineering at various scales.展开更多
文摘Two adsorption refrigeration working pairs of zeolite with water and ethanol were studied and the parameters of Dubinin-Astakhov model were regressed using the experimental data of equilibrium. The coefficient of heterogeneity varied from 1.305 to 1.52 for the zeolite-water pair and from 1.73 to 2.128 for zeolite-ethanol pair. The maximum adsorption capacity varied from 0.315 to 0.34 for zeolite-water and 0.23 to 0.28 for zeolite-ethanol, respectively. The results showed that the zeolite-water pair is suitable for solar energy cooling not only because of the high latent heat of vaporization of water but also because of the better equilibrium performance. On the other hand, zeolite-ethanol gives a high adsorption capacity at high regeneration tem-perature, which means it can be used in heat engine systems like buses and cars.
文摘Controlling the biogas fermentation process is the key for maintaining stable operation of biogas system and increasing gas yield. Aiming at features of biogas fermentation process and difficulties of control, a practical control scheme is proposed combining the abundant experience of biogas experts. And it discussed the structural design and hardware configuration of the expert control system, established the database and role base, and designed the control strategy of production system inference. The design scheme with ZigBee and PDA technology as core is employed so as to solve problems of environmental factor detection and data transfer management. The test result shows that the deviation of temperature is controlled within ± 0.9℃, the deviation of pH is controlled within ±0.3, the deviation of oxidation-reduction potential is controlled within ±30mV, the deviation of gas production is controlled within ± 9mL and that of methane concentration is controlled within ±4.5%. This system is easily expandable and applicable to biogas engineering at various scales.
