A versatile plant for converting biogas into high added value chemicals

Plant for the conversion of biogas into a chemical product with a high added value, selected among methanol, dimethyl ether, formaldehyde, acetic acid by a process comprising the following steps: a) reforming by converting methane and carbon dioxide contained in the biogas into syngas, b) synthesis of methanol by using syngas from step a), b') synthesis of one of the aforesaid chemical products: formaldehyde, dimethyl ether or acetic acid by using methanol from step b) c) optional purification and separation of said chemical product, characterized in that the reaction section in which the steps b) and b') are carried out or a part of it is replaceable with a further and different whole section or section part, in order to obtain one of the aforesaid chemical products different from the one obtained before said substitution. This plant can convert almost all or all the C02 produced in biogas plants into CO and subsequently into one or more chemical products with a high added value with revenues comparable to, if not higher than, those of traditional plants only obtainable thanks to incentives. The plant is energy self-sustainable thanks to the use of its effluents for the production of energy and heat.