The Impact of Solvent of Absorption CO2 from Biogas Vinasse

Abstract

Reduced energy reserves that occurred in Indonesia today, it needed a new source of alternative energy. Biogas is one of the alternative energy sources. Typical biogas contains 50–65% methane (CH4), 30–45% carbon dioxide (CO2), moisture and traces of hydrogen sulphide (H2S). Purification of biogas done to remove the impurities (inhibitor) on biogas such as carbon dioxide (CO2). Chemical absorption involves formation of reversible chemical bonds between the solute and the solvent. Chemical solvents generally employ either aqueous solutions of alkaline salts (i.e. sodium, potassium and calcium hydroxides). In the process of purification chosen liquid NaOH, KOH and Ca(OH)2 because theirs as absorbent material is highly reactive with CO2. This study aims to determine the The CO2 absorption using NaOH, Ca(OH)2 and KOH with the same consentration ( 15 % ). Absorption method used is missed biogas in the ` alkaline solution.The results showed that the absorption by using 15 % KOH concentration produced the higest CO2 absorption with the lowest CO2 content and the highest content of methane. The KOH solution can increased the CH4 content of biogas 70,3 % from 33,64 to 57,29 % by volume.The absorption of CO2 content of biogas was 100 % from 30,18 % to 0 % by volume.The NaOH solution can increased the CH4 content of biogas 67,07 % from 55,37 to 82,56 % by volume.The absorption of CO2 content of biogas was 100 % from 42,33 to 0 % by volume . The absorption of CO2 content usage Ca(OH) solvent was the lowest from the others.