Production of waste energy and heat in hospital facilities

Highly efficient utilization of the energy potential of waste is a crucial matter in the process of thermal conversion. A vast majority of research studies published to this date on electrical energy and heat recovery have been concerned with large MSW (municipal solid waste) incineration systems. Only few of the publications presented the research on electrical energy and heat recovery in small and medium incinerating plants. They were focused on the production of syngas (waste gasification) and its combustion in gas engines. The research studies described in the article included electrical energy and heat recovery from the medical waste incineration installation with the efficiency of 220 kg/h. The research was carried out in a large hospital facility. The tested installation consisted of three basic elements: HSRG (heat recovery steam generator), MT (microturbine) producing electrical energy and steam/water heat exchanger. The efficiency values of individual units were high: HRSG-78%, MT-79% and HT-99%. The total disposable enthalpy flux of steam entering the turbine was low and it was not possible to produce a sufficient amount of electricity. The average electrical energy flux produced during the tests amounted to <(E)over dot>(ue-MT) := 31.6 kWe, which constituted 4.2% of the total flux of usable energy recovered by the installation. The rest was the enthalpy flux of hot water - <(E)over dot>(ue-HE) = 729 kW (95.8%). Such installations can be used, provided that there are systems that are capable of receiving that type of heat throughout the entire calendar year. It was proven that the experimental installation had small impact on the environment. The SPB (simple payback period) of the investment expenditures incurred in order to complete the installation amounted to 3.1 years. (C) 2015 Elsevier Ltd. All rights reserved.