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In recent times, the methanol was employed in numerous innovative applications and is a key compound widely used as a building block or intermediate for producing synthetic hydrocarbons, solvents, energy storage medium and fuel. It is a source of clean, sustainable energy that can be produced from traditional and renewable sources: natural gas, coal, biomass, landfill gas and power plant or industrial emissions. An innovative methanol production process from coal gasification is proposed in this work. A suitable comparison between the traditional coal to methanol process and the novel one is provided and deeply discussed. The most important features, with respect to the traditional ones, are the lower carbon dioxide emissions (about 0.3%) and the higher methanol production (about 0.5%) without any addition of primary sources. Moreover, it is demonstrated that a coal feed/fuel with a high sulfur content allows higher reductions of carbon dioxide emissions. The key idea is to convert hydrogen sulfide and carbon dioxide into syngas (a mixture of hydrogen and carbon monoxide) by means of a regenerative thermal reactor. This is the Acid Gas to Syngas technology, a completely new and effective route of processing acid gases. The main concept is to feed an optimal ratio of hydrogen sulphide and carbon monoxide and to preheat the inlet acid gas before the combustion. The reactor is simulated using a detailed kinetic scheme.

This paper presents the experimental development at demonstration scale of an integrated gasification system fed with wood chips. The unit is based on a fixed-bed, updraft and air-blown gasifier—with a nominal capacity of 5 MWth—equipped with a wet scrubber for syngas clean-up and an integrated chemical and physical wastewater management system. Gasification performance, syngas composition and temperature profile are presented for the optimal operating conditions and with reference to two kinds of biomass used as primary fuels, i.e., stone pine and eucalyptus from local forests (combined heat and power generation from this kind of fuel represents a good opportunity to exploit distributed generation systems that can be part of a new energy paradigm in the framework of the circular economy). The gasification unit is characterised by a high efficiency (about 79–80%) and an operation stability during each test. Particular attention has been paid to the optimisation of an integrated double stage wastewater management system—which includes an oil skimmer and an activated carbon adsorption filter—designed to minimise both liquid residues and water make-up. The possibility to recycle part of the separated oil and used activated carbon to the gasifier has been also evaluated.

Gasification is a thermochemical process devoted to the production of syngas, starting from a solid fuel such as coal, biomass, or refuse-derived fuel (RDF). The gasification efficiency and the chemical composition of the produced syngas are strongly affected by the feedstock and the operating conditions of the process. Besides the direct use as a fuel for power generation, downstream applications of syngas for chemical production demand specific H 2 /CO ratios, as extensively reported in the literature. For this reason, in the present work, a comprehensive mechanistic approach is applied to the description of the coal gasification process, highlighting the sensitivity of key operating parameters on syngas quality. The solution of this multi-scale, multi-phase, and multi-component problem requires careful attention to the kinetics in the solid and the gas phase as well as the heterogeneous gas−solid reactions. The kinetic model is validated with experimental data obtained in updraft gasifiers (including the Sotacarbo pilot gasification plant), and the catalytic effects of ash on the reactivity of low-rank coals are also addressed and quantified.