No abstract

Biogas is the combustible gas produced through a biological process, known as anaerobic digestion which is the process operated at low-temperature and without air. Biogas consists of 55-80% CH 4 , 20-45% CO 2 with trace amount of H 2 S and other impurities. Common H 2 S removal technologies from biogas fall into one of adsorption on a solid such as iron oxide based materials, activated carbon or impregnated activated carbon. Conventionally, activated carbon is produced from biomass residues and agricultural residues such as palm oil shell which promising approach for the production of cheap. It is so due to the palm oil shell carries a large amount of carbon content which it is the main composition of activated carbon. Therefore, it is usable as raw material for producing impregnated activated carbon and used as adsorbents. The aim of this study is a produce the activated carbon from palm oil shells by chemical activation using ZnCl 2 and optimal conditions after impregnated them with NaOH, KI and K 2 CO 3 for H 2 S absorption from biogas product. In this research, production of activated carbon involved three stages; (i) carbonization of raw material in an inert atmosphere which was carbonized in a muffle furnace at 600°C for 1 h; (ii) secondly activation of char product from the first stages at fixed bed reactor (stainless steel with 54.1 mm internal diameter and 320 mm length) which was studied to observe the effect of char product: Chemical agent ratio (ZnCl 2 , 1:1 to 1:3), which there are activated at 700°C activation temperature for 2 h; and (iii) finally alkali impregnated activated carbon which were immersed 1:3 ratio in 500 mL of 1 N NaOH, KI and K 2 CO 3 solutions and stirred for 30 min. The result showed that the surface area and the pore volume increased progressively with increasing the char product: Chemical agent ratio. The maximum surface area total pore volume of activated carbon product was 532.31 m 2 /g and 0.2973 cc g −1 was obtained on ACZn13. While, the maximum surface area and the pore volume of modified impregnated activated carbon was 741.71 m 2 /g and 0.4210 cc g −1 was obtained on K 2 CO 3 -AC. The results of the experiment demonstrated that with regard to adsorption of H 2 S on K 2 CO 3 -AC which it had more than on KI-AC and NaOH was 3.26 and 8.8%, respectively. The conclusion showed that surface area, total pore volume and micropore volume were increasing with increased the char product: Chemical agent ratio (1:1 to 1:3). ACZn13 has good chemical and physical AJESproperties such as chemical content and surface area, which showed that the highest surface area (532.21 m 2 /g) and total pore volume (0.2973 cc g −1 ). Therefore, K 2 CO 3 -AC impregnated activated carbon has a high surface area and showed be an efficient adsorbent for removal of H 2 S from biogas product. Moreover, evaluating the content of H 2 S adsorption was suggested.

No abstract

No abstract

The growing worldwide concerns over environment, health and monetary aspects have triggered a search for efficient and economic renewable sources of energy production. Agricultural sector holds the potential for development of one of the major source of renewable energy such as biogas. In this study, CSTR-small scale fermentation (200 L stainless steel) was studied to observe the effect of stirring for natural water, cow dung, rice straw and water hyacinth ratio (2:1:1:1), which there are suitable of C: N ratio at 31.1: 1on the biogas and methane production at ambient temperature (31°C), 6.7-7.2 and 6.7-7.8 of pH for with/without stirring digester, respectively, for 52 days. The result showed that the biogas production increased progressively with stirring digester. The maximum biogas production and methane concentration was 98.56 L/days and 64.07% was obtained at stirring digester. This gave an increase of 7.56 over without stirring digester. Thus, agitation of digester can be used effectively as an operating strategy to optimize biogas production.