Anaerobic digestion of biodegradable municipal waste

Ovim radom razrađuje se bioplinsko postrojenje za obradu biorazgradivog otpada za područje Istarske županije na idejnoj razini. Prvi dio rada opisuje problematiku zbrinjavanja otpada, kako u Europskoj uniji tako i u Hrvatskoj. Naglasak je na nesrazmjeru između proizvodnje otpada naspram njegove oporabe; prevelike količine otpada bivaju odložene na odlagalištima umjesto da se odvajanjem na mjestu nastanka ili naknadnom separacijom dobiva čista frakcija, spremna za daljnju obradu i dobivanje proizvoda više vrijednosti poput komposta ili biometana. Središnji dio rada opisuje tehnologiju proizvodnje biometana iz biorazgradivog otpada procesom anaerobne digestije. Navedene su komponente postrojenja uz okvirno dimenzioniranje glavnih elemenata s obzirom na nastale količine otpada na promatranom području te na rezultate laboratorijskih ispitivanja sirovine. Rad je zaključen ekonomskom analizom isplativosti te analizom dobrobiti bioplinskog postrojenja za komunalni sektor gospodarenja otpadom u cjelini. Glavna, ali na prvu nevidljiva, dobrobit oporabe otpada bioplinskim postrojenjem jest kruženje ugljikovih tvari na način da se ne remeti prirodna ravnoteža stakleničkih plinova u atmosferi. Drugim riječima, kružna ekonomija biorazgradivim otpadom pridonosi klimatskoj neutralnosti i zaustavljanju negativnih klimatskih promjena.This paper elaborates a biogas plant for the treatment of biodegradable waste for the area of Istria County at a conceptual level. The first part of the paper describes the waste disposal issue, both in the European Union and in Croatia. The emphasis is put on the disproportion between waste production versus its recovery; excessive amounts of waste are disposed of in landfills instead of being separated at the place of origin or subsequently, to obtain a pure fraction, which is ready for further processing and obtaining higher value products such as compost or biomethane. The central part of the paper describes the technology of biomethane production from biodegradable waste in the process of anaerobic digestion. Components of the plant are listed with an approximate sizing of the main elements in regard to the amount of waste produced in the observed area and the results of laboratory tests of raw materials. The paper concludes with an economic cost-effectiveness analysis and an analysis of the biogas plant's advantages for the municipal waste management sector as a whole. The main, but at first invisible, benefit of waste recovery by a biogas plant is the circulation of carbon in a way that does not disturb the natural balance of greenhouse gases in the atmosphere. In other words, the circular economy of biodegradable waste contributes to climate neutrality and halting negative climate change