This thesis analyzes composting and anaerobic digestion processes using variant solutions for the treatment of 60,000 t/year of biodegradable waste. The beginning of the thesis provides a explanation of the current waste management system in Croatia. The main section describes the processes of composting and anaerobic digestion as an introduction to the calculation of variant solutions. The core of the thesis consists of calculations for four variant solutions for waste treatment in composting facilities or anaerobic digestion plants. The analysis of the impact of bio-waste transport from users to the facilities included two types of municipal vehicles, as well as the number of facilities or destinations for transport. As part of the calculations, the following analyses were conducted: greenhouse gas emissions, mass balance, energy balance, and business income and expenditure. The greenhouse gas emissions of the selected variants were compared to those that would result from landfilling bio-waste, both with and without a gas collection system. Circular waste management through the considered practices of composting and anaerobic digestion brings significant benefits in terms of resource efficiency, environmental emissions, and operating costs compared to landfilling biowaste. Therefore, circular management of biodegradable waste is not only a legal obligation but also a social imperative of every advanced society.

Ovaj diplomski rad analizira postupke kompostiranja i anaerobne digestije pomoću varijantnih rješenja za obradu 60.000 tona biorazgradivog otpada godišnje. Na početku rada objašnjen je trenutni sustav gospodarenja otpadom u Republici Hrvatskoj. U razradi je opisan postupak kompostiranja i anaerobne digestije kao uvod u proračun varijantnih rješenja. Glavni dio rada čine proračuni četiri varijantnih rješenja za obradu otpada u kompostištima odnosno postrojenjima za anaerobnu digestiju. Analiza utjecaja transporta biootpada od korisnika do postrojenja je uključivala dvije vrste komunalnih vozila, kao i broj postrojenja, odnosno odredišta za transport. U okviru proračuna provedena je analiza: emisije stakleničkih plinova, bilanca mase, bilanca energije te prihoda i rashoda poslovanja. Emisije stakleničkih plinova odabranih varijanti uspoređene s onima koje bi nastale odlaganjem biootpada sa i bez sustava otplinjavanja. Kružno gospodarenje otpadom kroz razmatrane prakse kompostiranja i anaerobne digestije donose značajne prednosti po pitanju resursne učinkovitosti, emisija u okoliš, a isto tako i glede troškova poslovanja u odnosu na odlaganje biootpada. Stoga je kružno gospodarenje biorazgradivim otpadom ne samo zakonska obveza nego i civilizacijski imperativ svakog naprednog društva.