1 Plant Archives Vol. 20, Supplement 2, 2020 pp. 3436-3439 e-ISSN:2581-6063 (online), ISSN:0972-5210 EXPERIMENTAL INVESTIGATION OF MUNICIPAL SOLID WASTES THROUGH PYROLYSIS Cesare Freda 1 , Enrico Catizzone 1 Vinod K. Sharma 2 , Giacinto Cornacchia 1 , Massimiliano Grieco 1 , Antonio Villone 1 and D Buddhi 3 1 Laboratory of Thermochemicalnad processes for waste and biomass valorisation, Italian Agency for New Technologies, Energy and Sustainable Economic Development, 75026 Rotondella, Italy 2 Division of Bioenergy, Biorefinery and Green Chemistry, ENEA – Italian Agency for New Technologies, Energy and Sustainable Economic Development, 75026 Rotondella, Italy 3 School of Mechanical Engineering, Lovely Professional University Phagwara, India Corresponding author: D Buddhi, Email: dharam.24816@lpu.co.in and dbuddhi@gmail.com Abstract During the last decade, pyrolysis (a thermal process in which a solid feedstock is heated in absence of oxygen to produce solid, liquid and gaseous fuels) has been proposed as an attractive alternative technology to the incineration for municipal solid waste, especially allowing conversion of waste into chemical and liquid fuels. No doubt this technology has been extensively used but the fact remains that several issues still need to be addressed for reliable industrialization. For example, formation of tars along the plant’s pipelines is the main drawback of this process. Moreover, experimental investigations are of paramount importance in order to have new insights about the effect of temperature, heating rate, residence time and feedstock type on the product distribution. It is worth to note that high temperature mainly increases gas yield while high heating rate with short residence time favor the formation of liquid phase. Furthermore, type of feedstock strongly affects the product distribution. The work reported in the present paper is focused predominantly on the pyrolysis of unsorted municipal solid wastes, using a pyrolysis plant at the lab –scale to study the effect of temperature on the product distribution. The plant at the lab-scale consists of a nitrogen-flow fixed bed reactor equipped with an internal thermocouple for the temperature control. Reactor out- stream is sent at several traps in which tars are condensed and recovered whilst gaseous stream is analyzed by gas-chromatography technology. Residual charcoal was characterized and some disposal strategies are proposed. Keywords : Pyrolysis, municipal solid wastes, waste valorization, energy, environment. Introduction The whole cycle of management of the municipal solid waste (MSW) is a common concerns in every country. Waste management is the process, in which the different kinds of wastes are being collected, processed and recycled in order to convert them into useful materials or to dispose them in an environment friendly way. Hierarchical actions were identified in the waste management. The most preferred options of the waste hierarchy are in the order: Avoidance, Reduction of Wastes, Reuse, Recycle, Energy Recovery, Treatment and Disposal. Avoidance is the first action priority in the waste management. According to this principle, the manufacturing industries should use less hazardous materials in the design and manufacturing of the products in a ecofriendly way. Reduction of Wastes is the second preferred option. According to it, the companies should take actions to change the type of materials that are being used for the production of the specific products, so as to ensure that the by-products are of the least toxicity. Reuse is the third action in waste management strategy, in which the waste is not allowed to enter into the disposal system. The wastes are collected in the middle of their cycle and they are again fed to the production process. This action reduces the amount of wastes, saves the materials and reduces the production and manufacturing costs of the products. With the fourth action the “Recycle” the waste materials are collected, processed and used in the production of a new product. The Recycle saves materials, energy and production cost. The fifth action is energy recovery also called as waste to energy conversion. The wastes, that cannot be recycled, are being converted into useable forms of energy such as heat, light and electricity etc. This helps in the saving of various natural resources. Various processes such as combustion, pyrolysis, gasification anaerobic digestion, landfill gas recovery, are being implemented to carry out the conversion from waste to energy. The disposal to landfills is the last and worse action in the waste management hierarchy. Pyrolysis is well-known process usually used to produce charcoal mainly starting from biomass. Recently, quite homogeneous wastes such as tyres, car-fluff and plastics were used as feedstock for pyrolysis. When applied to waste management, MSW can be turned into fuel and safely disposable substances (char, metals, etc.), and the pyrolysis process conditions can be optimized to produce either a solid char, gas or liquid/oil product, namely, a pyrolysis reactor acts as an effective waste-to-energy convertor. MSW is more heterogeneous in composition and size compared to tyres and plastics, therefore MSW pyrolysis is more challenging. MSW consists mainly of paper, cloth material, yard waste, food wastes, plastics and a small amount of leather and rubber, metals, glass, ceramic, earthen materials and miscellaneous other materials. The as collected MSW could have a moisture content up to 80 wt.%. The high moisture content must be duly taken into account in a thermochemical process such as pyrolysis. The pyrolysis process is strictly influenced by some process variables such as temperature, heating rate, size of the material, residence time of solid and gas in the reactor. Temperature, could range from 300 to 900 °C, but the typical running temperature is around 500–550 °C. At these temperature the liquid is the major portion of products. At higher temperature the syngas yield increases. The residence time of the solid materials in the reactor is another important parameter; which was reported to be in the range from a few seconds to 2 h. The