Bio-Drying Role in Changeable Scenarios of Romanian MSW Management

The aim of this paper is to propose solutions for Romanian MSW treatment based on the bio-drying process as a tool for supporting the transient period necessary for complying with the EU regulations. In particular, the purpose of this paper is to compare four scenarios suitable for municipal solid waste (MSW) treatment. This case-study is interesting as waste management in Romania is changing quickly as a consequence of its recent entrance into the EU. For each scenario mass and energy balances have been developed taking into account the waste ultimate and proximate analysis, the lower heating value (LHV) of waste and also the energy consumption of each step of treatment. Results showed that selective collection plays an important role in decreasing the mass to be landfilled. The grate system guarantees the highest exploitation of the initial energy content of waste, but in this paper, direct combustion is not considered (the LHV of Romanian MSW is so low for a good combustion). A pre-treatment before combustion on grate is controversial because the addition of a treatment stage increases the cost of the management. Results demonstrated that a fluidized bed cannot give back the energy necessary for preparing Refuse Derived Fuel (RDF). This limit resulted also from the scenario with gasification. The use of RDF in a large thermal power plant as a substitute of coal can exploit the higher efficiencies of the electricity conversion; in the study the LHV of RDF is anyway critical and alternative solutions must be taken into account for increasing its energy content.