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Biomass gasification for energy purposes has several advantages, such as the mitigation of global warming and national energy independency. In the present work, the data from an innovative and intensified steam/oxygen biomass gasification process, integrating a gas filtration step directly inside the reactor, are presented. The produced gas at the outlet of the 1 MWth gasification pilot plant was analysed in terms of its main gaseous products (hydrogen, carbon monoxide, carbon dioxide, and methane) and contaminants. Experimental test sets were carried out at 0.25–0.28 Equivalence Ratio (ER), 0.4–0.5 Steam/Biomass (S/B), and 780–850 °C gasification temperature. Almond shells were selected as biomass feedstock and supplied to the reactor at approximately 120 and 150 kgdry/h. Based on the collected data, the in-vessel filtration system showed a dust removal efficiency higher than 99%-wt. A gas yield of 1.2 Nm3dry/kgdaf and a producer gas with a dry composition of 27–33%v H2, 23–29%v CO, 31–36%v CO2, 9–11%v CH4, and light hydrocarbons lower than 1%v were also observed. Correspondingly, a Low Heating Value (LHV) of 10.3–10.9 MJ/Nm3dry and a cold gas efficiency (CGE) up to 75% were estimated. Overall, the collected data allowed for the assessment of the preliminary performances of the intensified gasification process and provided the data to validate a simulative model developed through Aspen Plus software.

Production of energy or chemicals from biomass and several waste substrates appears a concrete strategy for replacing fossil fuels and reducing carbon dioxide emissions in the atmosphere. In particular, methanol from biomass or bio-waste is considered a reliable energy vector and key intermediate for industrial chemistry. Currently, methanol is industrially produced via syngas conversion using natural gas as the main feedstock. Bio-methane produced via anaerobic digestion (AD) of Organic Fraction Municipal Solid Wastes (OFMSW) may be used as an alternative to natural gas for production of syngas with optimal composition via commercialized reforming processes. In this work, a techno-environmental assessment for methanol production from biogas is presented and discussed. In particular, three case studies were assessed to minimize the environmental impact of bio-methanol production.

Phenol is a major component in the scrubber wastewater used for syngas purification in biomass-based gasification plants. Adsorption is a common strategy for wastewater purification, and carbon materials, such as activated carbons and biochar, may be used for its remediation. In this work, we compare the adsorption behavior towards phenol of two biochar samples, produced by pyrolysis and gasification of lignocellulose biomass, with two commercial activated carbons. Obtained data were also used to assess the effect of textural properties (i.e., surface area) on phenol removal. Continuous tests in lab-scale columns were also carried out and the obtained data were processed with literature models in order to obtain design parameters for scale-up. Results clearly indicate the superiority of activated carbons due to the higher pore volume, although biomass-derived char may be more suitable from an economic and environmental point of view. The phenol adsorption capacity increases from about 65 m/g for gasification biochar to about 270 mg/g for the commercial activated carbon. Correspondingly, service time of commercial activated carbons was found to be about six times higher than that of gasification biochar. Finally, results indicate that phenol may be used as a model for characterizing the adsorption capacity of the investigated carbon materials, but in the case of real waste water the carbon usage rate should be considered at least 1.5 times higher than that calculated for phenol.

This paper addresses the study of a pyro-gasification plant designed, built, and operated to recover inert metals from different types of solid waste. Experimental tests were carried out using pulper as the solid waste. However, while a reliable composition analysis of the produced syngas was carried out, a precise composition evaluation of the pulper used during the experimental activities was not performed and the related data were characterized by unacceptable uncertainty. Therefore, with the aim of reliably characterizing the plant operation, a thermochemical model of the gasification process was setup to simulate the equilibrium operation of the plant and a vector optimization methodology was used to calibrate the numerical model. Then, a decision-making problem was solved to identify the most suitable optimal solution between those belonging to the Pareto optimal front, thus obtaining reliable composition data for the adopted pulper waste. In particular, four different identification criteria were applied for the selection of small subset of solutions over the 3138 dominant solutions found. Among them, the solution (i.e., set of calibration parameters) that minimizes the experimental-numerical difference between the lower heating value of the produced syngas seemed to provide the most reliable approximation of the real plant operation. Finally, a possible plant configuration is proposed for the energetic valorization of the pulper waste and its overall conversion process efficiency is estimated.

There are more than 70 sugar producer countries around the world. Most of them are underdeveloped and poor. Especially for the underdeveloped, 3 rd world, the sugarcane residues disposal has first order priority. The lack of an alternative energy carrier to electricity with storage capability for use in off-season has to date been an unsolvable question for the sugar agro-industry. The improvement of cogeneration capacity via implementation of more efficient cogeneration systems and the barriers for their implementation were analyzed. A techno-economic assessment was carried out regarding the three most probable scenarios of sugar producer countries today. The biomass availability and high investment costs continue to be the main barriers to overcome in order to produce Bio-oil starting from sugarcane biomass solid residues.

The main objective of the present experimental investigation was to evaluate the effects of using different bacteria inoculums at identical technical settings on the anaerobic digestion process for the treatment of semi-solid organic waste available from the orthofruit market. As a possible means to improve the biogas production, as well as reduce their pollution potential, the idea of using recycled digested sludge from the reactor, along with the orthofruit waste, while operating the reactor at maximum retention period has been applied. Purification of the biogas produced was done by means of CO2 adsorption, resulting in a higher CH4/CO2 ratio and, thus, improving its use as fuel for power generation.

The lack of an alternative energy carrier to electricity with storage capability for use in off-season has to date been an unsolvable question for the sugar agroindustry. The improvement in cogeneration capacity via implementation of condensing extraction steam turbines or biomass integrated gasifier/gas turbine combined cycle and the barriers for their implementation were analyzed. The introduction of a fast pyrolysis (3 tons/h) module (FPM3) as a solution for off-season energy demand in the sugarcane agroindustry was also analyzed. The production cost of 1 ton of bio-oil for FPM3 condition was calculated at 87 USD/ton of bio-oil (0.104 USD/l of bio-oil). The economic feasibility of the FPM3 was estimated, comparing the added values for two alternatives: first alternative regarding the sugar and bioethanol simultaneous production (first generation biofuel production) and second alternative regarding the sugar and bio-oil simultaneous production (second generation biofuel production). Although the highest added value figure for a ton of sugarcane (49.30 USD) was gotten by the second alternative, the bioethanol production for cars fuel continues to be most attractive business option because of large fuel ethanol market demand.