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The solid residue of biorefining activities, namely the production of 2nd generation ethanol, was gasified in a pilot plant based on an updraft gasifier and equipped with cleaning and upgrading sections to remove tar and to increase the hydrogen content in the syngas. The operation of the facility proved that fixed beds can be used to gasify this feedstock despite the high content of lignin, a macromolecule whose thermoplastic behaviour at low temperature is well known. The obtained gas composition and yields are comparable with those reported for other virgin biomass converted in similar gasifiers.

Are presented some results achieved about process optimization of bioethanol production from wheat straw. The process consisted of three main steps: 1) Biomass pretreatment; 2) Enzymatic hydrolysis; 3) Glucose fermentation. To perform the hydrolysis step, commercial enzymatic mixtures were employed, mainly composed by beta-glucosidase (cellobiase), endo-glucanase and exo-glucanase. The ethanologenic yeast Saccharomyces cerevisiae was used to ferment the glucose in the hydrolyzates. Hydrolysis yield of 97% was achieved with steam exploded wheat straw treated at 220 °C for 3 minutes and an enzyme to substrate ratio of 0.04 w/w. It was pointed out the necessity of washing with water the pretreated wheat straw, in order to remove the biomass degradation products, which showed an inhibition effect on the yeast. A fermentation yield of 95% was achieved at the best process conditions. In the Simultaneous Saccharification and Fermentation , a global conversion of 92% was obtained, which corresponds to the production of about 170 grams of ethanol per kilogram of detoxified substrate. 1. INTRODUCTION While the productions of ethanol from sugar juice and starch are well-established technologies, using lignocellulosic biomass as feedstock raises problems of cumbersome solution (Godon, 1993). Cellulose and hemicellulose cannot be saccharified by enzymes at reasonable yields because lignin works as a shield to prevent chemical and microbial degradation. Many pretreatments were proposed to obtain free fermentable sugars from lignocellulosics, both of chemical and thermomechanical type, among them steam explosion (SE) was evaluated as one of the most promising (Sivers and Zacchi, 1996). This pretreatment involves the biomass exposure at saturated steam followed by a sudden decompression (explosion). Chemical hydrolysis of bonds between lignin and carbohydrates and mechanical defibration are the key factors in steam explosion ability to increase enzymatic accessibility. In this stage temperature and exposure time are important process variables in increasing the "treatment severity" conditions. High severity allows to obtain higher saccharification yield in the subsequent stage, but involve higher carbohydrates degradation and higher concentration of inhibitors. &nbsp

The use of lignocellulosic biomass to obtain biofuels and chemicals produces a large amount of lignin as a byproduct. Lignin valorization into chemicals needs efficient conversion processes to be developed. In this work, hydrocracking of organosolv lignin was performed by using nickel Raney catalyst. Organosolv lignin was obtained from the pretreatment of eucalyptus wood at 170 °C for 1 h by using 1/100/100 (w/v/v) ratio of biomass/oxalic acid solution (0.4% w/w)/1-butanol. The resulting organic phase of lignin in 1-butanol was used in hydrogenation tests. The conversion of lignin was carried out with a batch reactor equipped with a 0.3 L vessel with adjustable internal stirrer and heat control. The reactor was pressurized at 5 bar with hydrogen at room temperature, and then the temperature was raised to 250 °C and kept for 30 min. Operative conditions were optimized to achieve high conversion in monomers and to minimize the loss of solvent. At the best performance conditions, about 10 wt % of the lignin was solubilized into monomeric phenols. The need to find a trade-off between lignin conversion and solvent side reaction was highlighted.

Industries currently rely on chicory and Jerusalem artichoke for inulin extraction but also cardoon is proved to synthetize and store high quantity of inulin in roots as well. Cardoon is a multipurpose crop, well adapted to marginal lands, whose main residues at the end of cropping cycle consist of roots. However, cardoon roots are a suitable source of inulin, that is of high interest for new generation biodegradable bioplastics production. On the other hand, a sustainable supply chain for inulin production from cardoon roots has not been developed yet. In particular, in the inulin supply chain the most critical part is storage, which can negatively affect both cost and inulin quantity. In the present study the effect on inulin content in cardoon roots stored as dried chipped roots (CRt) and dried whole roots (WRt) was investigated in a 6-month storage trial. Our findings suggest that chipping before storage did not affect the inulin content during the storage. Furthermore, it reduced the time needed for drying by 33.3% and increased the bulk density by 154.9% with the consequent reduction of direct cost for drying, transportation and storage., This research was performed within the Italian Project COMETA-Autoctone Mediterranean crops and their valorization with advanced green chemistry technologies. The project was funded by Ministry of Education, Universities and Research in the frame of PON "Ricerca e Innovazione" 2014���2020 and FSC/ARS01_00606 COMETA/CUP. B2G18000180004/Azione II.

In this paper the lignin gasification by using water in supercritical was studied. The employed lignin was produced via steam explosion of Arundo Donax after alkaline extraction and filtration. The lignin, with a total solid content of about 4 wt% in a solution of sodium hydroxide which confers to the solution a pH of about 11, was fed in a continuous PFR bench scale reactor able to operate at supercritical water conditions. The experiments were carried out at 550 °C and 250 bar by varying the feed flow rate from 10 mL/min to 60 mL/min in order to understand the effect of the residence time on the liquid and solid phases in terms of volume composition, liquid phase composition, carbon and global gasification efficiency. The main results showed that by using lignin after alkaline extraction, syngas with a higher heating value (HHV) greater than 40 MJ/kg without CO2, mainly composed by hydrogen and methane, was obtained. At the same time, in the liquid phase the presence of some compounds, such as glucose, syringaldehyde, formic acid, acetic acid and xylose, was revealed, and all these species are included in the main building block group for the green chemistry or for the development of bioprocess for high added value intermedia production. © 2018 Elsevier Ltd

Wheat straw and eucalyptus residues were pretreated in a biphasic system, constituted of butanol (n-butanol) or 2-methyltetrahydrofuran (2M-THF) and aqueous oxalic acid solutions. The pretreatments were carried out in a 300 mL Parr reactor (Autoclave Buchi Limbo-li®) with a solid load of 5 wt.%, the temperature in the range 140–180 °C, oxalic acid load from 0 to 10 wt.% and a duration of 30–90 min. The obtained slurry was then fractionated in three streams: the aqueous phase which contained solubilized hemicellulose, the organic phase which contained the solvated lignin, and the solid residue which contained cellulose. The solid was hydrolyzed using a commercial mix of enzymes to assess cellulose digestibility and glucose production. The pretreatment was optimized to maximize the purity of the cellulose and hemicellulose fractions and the glucose recovery as free sugar. The optimization was done by using an experimental design and response surface methodology. The mass flow details of the four optimized processes were obtained. In terms of biomass fractionation, butanol demonstrated significant advantages over 2M-THF in the same range of process conditions as shown by the recovery yield of free glucose which reached 98% of the theoretical value with butanol but was 67% with 2M-THF. Tests at low temperature and low enzyme loading highlighted the importance of the solvent choice over the operating conditions. 2M-THF showed interesting performances only in the delignification step, with 90% efficiency for the straw. Regarding the use of different feedstock, fractionation and recovery were generally higher for wheat straw than for eucalyptus wood residues.

The aim of the paper is to evaluate the bioenergy and bio-based material recovery from fruit scraps through an innovative process, e.g., supercritical water gasification, which presents several advantages in comparison to the traditional processes for energy and matter recovery. In particular, experimental tests of peach scraps were carried out using bench-scale plant plug flow reactor type, in which the selected liquid matter can be pumped until 300 bar and heated until 600°C to achieve the supercritical water condition of the water. The main results showed that, in the range of the feed flow rate of 5-30 mL/min and at fixed operative conditions of T and P (T = 550°C, and P = 250 bar), it is possible to obtain tar-free syngas with a higher heating value of 14-16 MJ/kgdry basis. The influence of the residence time was studied for the gaseous and liquid phases. For each one of them, it was possible to highlight a specific trend. In the liquid phase, the main components were acetic acid, hydroquinone, and syringaldehyde that are intermediates for the chemical synthesis of interesting bio-based chemicals and biochemicals. © 2016 American Chemical Society.

There is a perceived need for multi-fuel burner geometries capable of operating with variable composition fuels from diverse sources to achieve fuel flexibility in gas turbines. The objective of the research covered herein is a comparison study between two liquid fuels, a biodiesel (in a pure form) and the biodiesel as a saturated mixture with a pyrolysis by-product; these two fuels were compared against a standard kerosene as a baseline. The research methodology involved two stages: firstly atomization patterns and injection regimes were obtained using a high speed imaging method, secondly a combustion test campaign was undertaken using a swirl burner to quantify the operational behaviour, species production and exhaust gas compositions of the fuels. Emissions, flame stability trends and power outputs were measured at gas turbine relevant equivalence ratios. Excess oxygen and atomization trends in the biodiesel seem to be playing a major role in the production of emissions and flame stability when compared to kerosene. Also, heavy organics seem to be acting as catalytic substances for OH production close to the burner mouth. In terms of stability and combustion, it is proposed that the saturated blend would be a viable candidate for power generation. © 2016

One feedstock of composted agro-energy co-products and agricultural residues was physically-chemically-microbiologically characterized and investigated for the phytotoxic property and the disease suppression for finding next-generation “green composts” suitable for use in horticultural soil-less systems. The suppression of three composts made of crude steam-explosion liquid-waste of miscanthus (SELWM), giant reed (SELWA) and wheat straw (SELWWS) mixed with the agro-waste mostly available in Southern Italy [CWS (SELWWS + woodchip + tomato-waste), CM (SELWM + coffee-ground + artichoke-waste) and CA (SELWA + defatted olive marc + fennel-waste)] was tested by the in vitro and in vivo experiments against seven horticultural pathosystems (Phytium ultimum/Cucumber, Phytophthora nicotianae/Tomato, Rhizoctonia solani/Bean, Sclerotinia sclerotiorum/Lettuce, Fusarium oxysporum f. sp. melonis/Melon, Fusarium oxysporum f. sp. lycopersici/Tomato,and Verticillium dahliae/Eggplant). One compost (CC) sourced from the differentiated municipal bio-waste with pathogen-specific property was employed as reference. The phytotoxicity of composts was assessed on lettuce and cress. In vitro bioassays carried out on pure colonies showed that raw compost water extracts (CWEs) were able to inhibit all of pathogens adopting a pouring technique, and that a well-cut diffusion method allowed the block of growth of the pathogens without physical interaction with compost microflora. The sterile-filtration of CWEs annulled inhibition of the pathogens, but S. sclerotiorum and V. dahliae were inhibited by sterile CWEs using a pouring procedure. In vivo tests performed under greenhouse conditions using peat-based plant growing media amended with each compost at dosage of 20% (v/v) showed multi-suppressive activity: CWS suppressed most efficiently P. ultimum, R. solani, P. nicotianae, F. oxysporum f. sp. melonis, F. oxysporum f. sp. lycopersici, V. dahliae; CM was capable to suppress P. ultimum, R. solani, P. nicotianae, S. sclerotiorum, V. dahliae; CA was suppressive against R. solani, P. nicotianae, V. dahliae. The microbiological inactivation of composts by heating treatment reduced suppression in all of pathosystems, but for S. sclerotiorum/Lettuce and V. dahliae/Eggplant the loss of suppressivity was smaller in CA, CM and CC. The predictive parameters to suppression were different: total fungal biomass for P. nicotianae; FDAH for P. ultimum; Trichoderma for R. solani; Aspergillus, Pseudomonas and Streptomyces for F. oxysporum. Instead, the parameters that drive suppression of S. sclerotiorum and V. dahliae were not well cleared. The use of composted agro-waste seems to be an efficient alternative to peat-based substrates for controlling diseases on a broad range of horticultural crops with inappreciable phytotoxic effects if added in moderate dose. © 2016 Elsevier B.V.

Highlights • The use of a paddle dryer system in the bioethanol process from straw is proposed. • Paddle dryer was employed to detoxify a pretreated substrate by steam explosion. • Paddle dryer is resulted an efficient system to improve enzymatic hydrolysis., The advantage of using paddle dryers (PD) in the production of sugars and 2nd generation ethanol from pretreated wheat straw was investigated. This machinery was employed in order to detoxify steam-exploded substrates and to mix different slurries in the hydrolysis step. The obtained hydrolysate was fermented by the yeast Saccharomyces cerevisiae. Acetic acid and furfural were reduced up to 11 and 26 fold respectively in the detoxified substrate. When fermentation was carried out at low solid suspension, the use of PD was as effective as water extraction in detoxifying exploded biomass, giving ethanol yields of 90% at 0.05 solid/liquid ratio (S/L) and 80% at 0.10 S/L. Moreover, by using PD the cellulose conversion yield was significantly improved in the hydrolysis step: when operating at higher S/L (0.4), the hydrolysis efficiency was twice the one achieved by using a bioreactor with a Rushton stirrer.

An innovative 1000 kWth pilot plant based on a bubbling fluidized bed gasifier with internal recirculation was operated in experimental campaigns of biomass gasification. The evaluations were focused on the gasifier performances and quality of the product gas. To this aim, tests were carried out at atmospheric pressure using almond shells as a feedstock and three defined gasification mediums (i.e. steam/O2 mixture, 35wt.% and 50wt.% O2 enriched air); process temperature was in the range 820-880 °C. The result assessment allowed to evaluate the system flexibility to the gasifying agent and acquire data on the gas producible with this specific configuration. Based on the dry compositions, LHVs in the range 5.9-6.7 MJ/Nm3 dry, 6.3-8.4 MJ/Nm3 dry and 10.9-11.7 MJ/Nm3 dry were respectively calculated for the three product gases. Correspondingly, an increase in the cold gas efficiency from 0.5 up to 0.7 was also estimated. Concerning the contaminant loads, in the case of the tests related to steam/O2 biomass gasification, particle and tar contents were found in the range 6-10 g/Nm3 dry and 12-18 g/Nm3 dry, respectively, while H2S, HCl and NH3 were at concentrations below 100 ppms (v). © 2015 Elsevier B.V. All rights reserved.

The goal of this work is to investigate the potentiality of energetic recovery by sewage sludge gasification. Experimental gasification tests were carried out in a bench scale rotary kiln under simulated autothermal condition. The mass rate of sludge was in the range 170–260 g/h. The gasification temperature was varied from 750 to 850 °C, equivalence ratio was increased up to 0.24. The tests run for about 3 h. Input and output streams of the process were quantified and analyzed as to assess the cold gas efficiency. Tar content in the raw gas was determined as well. The main drawbacks occurred during the tests were highlighted to have a realistic frame of the experimented technology. © 2017 Elsevier Ltd

The work highlighted the influence of the water content within the starting biomass, drying procedure and ripeness on the enzymatic digestibility of the giant reed, one of the most suitable nonfood crops for bioenergy and bio-compound production. Fresh green reed was treated as received, while oven-dried green and ripe reed were humidified before the steam explosion pretreatment that was carried out at 210 ℃ for 10 minutes. The exploded biomasses were extracted with water to remove the soluble hemicellulose and potential inhibitors; the insoluble residue was submitted to enzymatic hydrolysis and alcoholic fermentation. The process was evaluated in terms of sugars recovery and ethanol yield. After the sequence of pretreatment, enzymatic hydrolysis and fermentation by Saccharomyces cerevisiae 132 g; 103 g; 162 g of ethanol; and 77 g; 63 g; 92 g of pentosanes were respectively obtained from 1 kg DM of fresh green reed; dried green reed or ripe reed. The ripe reed contains more carbohydrates than the green reed and the resulting sugar and ethanol production was higher, in spite of lower saccharification yield. While drying the fresh biomass is good practice for biomass preservation, it negatively affects the recovery of free sugars and the ethanol production, because of fiber hornification which hinders enzyme access in the hydrolysis step.

Autothermal gasification of lignin-rich residues was carried out to evaluate the performances of a pilot plant with a feeding rate of 20-30 kg h-1 of feedstock. The facility was based on an updraft gasifier and a gas cleaning train composed of a biodiesel scrubber and coalescence filters. The tests were performed with solid residues of ethanol production starting from straws or canes. Air at a low equivalence ratio was used as gasification medium. The autothermal processing and the lignin-rich feedstock made it possible to highlight a sequence of exothermic and endothermic reactions by measuring the heating rates along the reactive bed. The CO2 production was proportional to the ash content. The average production of raw syngas was 1.94 kg per kg of dry residue, of which H2 and CO were 27.2 and 696 g, respectively. The efficiency of energy conversion from solid to cold gas was 64% and reached about 81% including the contribution of the condensable organic fraction. © 2014 American Chemical Society.

The paper reports on experiments of glucose gasification with water in supercritical conditions (SCW). The adoption of these process conditions revealed advantages in terms of biomass conversion efficiency as the resulting liquid phase includes some important compounds (Acetic Acid, 5-HFM, furfurals). In addition the high operative pressures allow either to consider the possibility to use this technology inside the steam cycle in order to produce power and liquid/gaseous biofuels such as synthetic natural gas and/or methanol/DME(di methyl ether). In fact, from the experimental tests, it was possible to evaluate that using glucose, that is the main intermedia of SCW gasification from wet biomass, is possible to estimate a syngas production of about 100 lt – 200 lt for each kg of glucose fed, while the global gasification efficiency was of about 10–18%. Syngas product to SCWG has been analysed and the main results shows that, in the range investigated, CO content was 40–50%vol., H2 10–15%, CH4 10–20%, C2+2–8% and at the end CO2 with a volume content of about 20–30% and then with lower calorific value of about 20 MJ/Nm3. Analysis on the liquid phase was carried out and the main results has been an high production of both 5-hydromethil furfural and 2-Furaldehyde that have a great potential as “carbon-neutral” feedstock for fuels and green chemicals.

Automotive shredder residue (ASR) can create difficulties when managing, with its production increasing. It is made of different type of plastics, foams, elastomers, wood, glasses and textiles. For this reason, it is complicated to dispose of in a cost effective way, while also respecting the stringent environmental restrictions. Among thermal treatments, pyrolysis seems to offer an environmentally attractive method for the treatment of ASR; it also allows for the recovery of valuable secondary materials/fuels such as pyrolysis oils, chars, and gas. While, there is a great deal of significant research on ASR pyrolysis, the literature on higher scale pyrolysis experiments is limited. To improve current literature, the aim of the study was to investigate the pyrolysis of ASR in a bench scale rotary kiln. The Italian ASR was separated by dry-sieving into two particle size fractions: d 30mm. Both the streams were grounded, pelletized and then pyrolyzed in a continuous bench scale rotary kiln at 450, 550 and 650°C. The mass flow rate of the ASR pellets was 200-350g/h and each test ran for about 4-5h. The produced char, pyrolysis oil and syngas were quantified to determine product distribution. They were thoroughly analyzed with regard to their chemical and physical properties. The results show how higher temperatures increase the pyrolysis gas yield (44wt% at 650°C) as well as its heating value. The low heating value (LHV) of syngas ranges between 18 and 26MJ/Nm3dry. The highest pyrolysis oil yield (33wt.%) was observed at 550°C and its LHV ranges between 12.5 and 14.5MJ/kg. Furthermore, only two out of the six produced chars respect the LHV limit set by the Italian environmental regulations for landfilling. The obtained results in terms of product distribution and their chemical-physical analyses provide useful information for plant scale-up.

Chemical compositions of 80 vegetable oils were collected from literature and the properties of the obtainable biodiesel (methyl esters) have been predicted by empirical relationships. The purpose has been to check the viability of predicting if a biodiesel could meet the EN 14214 standards knowing only the fatty acid profile (FAP) of the parent oil. Two parameters were used in this investigation: (i) average number of carbon atoms in the fatty acid chains, (ii) average number of double bonds (CC) per molecule. Two new empirical relationships have been proposed to predict the viscosity and the cetane number of biodiesel from the two parameters. The range of values of the two parameters leading to biodiesel meeting the EN 14214 standard for viscosity, cetane number, iodine value, and cold filter plugging point have been graphically obtained by overlapping the corresponding level surfaces. Practical applications: This work provides biodiesel producers with indications of the quality of biodiesel without the need for analytical testing of the product (indeed, of the product itself). Only the fatty acid profile of the starting vegetable oil is required. The quality of biodiesel can be estimated by using a chart developed in this work, allowing to estimate, e.g. if the biodiesel meets the European standards. The work can be useful to rapidly screen oil seed crops in studies of genetic engineering that require high throughput.

The antifungal activity of steam-exploded liquid waste (SELW) produced by the detoxification of steam-exploded biomass of Miscanthus sinensis, Arundo donax and wheat straw for 2nd generation industrial bioethanol production was studied against plant pathogenic fungi for the first time. Quantification of fermentation inhibitors (2-furaldehyde, 5-hydroxymethylfurfural, acetic and formic acid) was carried out by standard methods. Mycelial growth inhibition and conidial germination of eight fungal strains [Alternaria alternata, Botrytis cinerea, Colletotrichum acutatum, Cladosporium fulvum, Fusarium oxysporum f. sp. lycopersici (FOL), F. oxysporum f. sp. melonis (FOM), F. solani f. sp. pisi and Verticillium dahliae] were evaluated in vitro at different dilution rates (1:2, 1:4 and 1:8) for each SELW. Disease suppressiveness was assessed in vivo in eight horticultural pathosystems (A. alternata/tomato, B. cinerea/tomato, C. acutatum/strawberry, C. fulvum/tomato, FOL/tomato, FOM/melon, F. solani f. sp. pisi/pea and V. dahliae/eggplant) under greenhouse conditions. Pathogen suppression by each SELW, applied both in spray form on to tomato leaves and skins of tomato and strawberry, and by means of dipping method in watering suspensions on to seedling root systems of tomato, melon, pea and eggplant, was evaluated at dilution rates of 1:2, 1:4 and 1:8 using irrigation water during curative and preventive treatments. Investigations carried out in vitro showed that M. sinensis SELW was more suppressive than wheat straw SELW, and A. donax SELW was less suppressive than wheat straw SELW at the lowest dilution rates. Relationships between the concentration of 2-furaldehyde, acetic and formic acid present in SELWs and their antifungal effect were found. Moreover, B. cinerea, C. fulvum, V. dahliae, A. alternata, C. acutatum and F. solani f. sp. pisi were more effectively inhibited than FOL and FOM. Investigations performed in vivo showed that SELWs of M. sinensis and wheat straw can be diluted at a 1:2 rate and used for controlling six fungal diseases during preventive treatments. In particular, they can be used by dipping of the root systems during transplanting in the case of F. solani f. sp. pisi/pea and V. dahliae/eggplant; on the other hand, they can be nebulized on to the leaves and fruits before symptoms appearance in the case of A. alternata/tomato, B. cinerea/tomato, C. acutatum/strawberry and C. fulvum/tomato. This study is of particular interest because it points out how these SELWs could be employed in horticultural crop protection in Southern Italy, thereby making it possible to effectively combine industrial production of 2nd generation biofuels with sustainable horticulture under greenhouse conditions.

A special type of bioreactor was designed and tested in order to improve the bioethanol production from lignocellulosic materials via enzymatic hydrolysis and fermentation. The reactor consists of two chambers kept at different temperatures and separated by a porous medium, through which the solutes can diffuse. The reactor was tested using as substrate wheat straw previously steam exploded and detoxified. The yields of cellulose hydrolysis and glucose fermentation obtained using this reactor were compared to those obtained by simultaneous enzymatic hydrolysis and fermentation (SSF) carried out in only one vessel. The results showed that a significant increase in the ethanol yield (20%) can be achieved by using this bioreactor. An additional advantage of the reactor is the confinement of the solid lignin in one chamber, allowing a simplified separation process between broth and unreacted residue. © 2012 Elsevier Ltd.

Three solid catalysts have been tested in the transesterification of fried oils: CaO, SrO, K 3PO 4. For CaO and SrO the different efficiency, between their use as powder or granules, has been examined. Another investigated aspect has been the catalytic activity at different catalyst loadings and recycles. At the end granules have been employed in a catalytic bed reactor, comparing results with batch systems. Results have shown that using catalyst as granule does not affect the yields after 3 h of reaction. The use of the catalytic bed reactor has given the possibility to perform the transesterification maintaining the catalyst separated from the reactants, without loss of efficiency; in fact the comparison between trials in batch reactor and in catalytic bed system has not shown differences in yields. After 3 h of reaction, at 65°C, 5 wt% of catalyst, we have had the following FAME yields: 92% for CaO, 86% for SrO, 78% for K 3PO 4. The transesterification reaction has shown a sensitive influence respect to K 3PO 4 granules amount used; in fact the yield has reached the 85% using 10 wt% of catalyst. The reutilization of the catalyst, without regeneration, has shown a loss of efficiency of about 10-20% in decreasing yield. © 2011 Elsevier B.V. All rights reserved.

This paper reports the use of lignin-rich solid, derived from enzymatic hydrolysis of lignocellulosic biomass, to produce syngas and pyrolysis oil. The tested process was an updraft gasification carried out at pilot scale of about 20 kg/h as solid feed. The reactivity of two residues, one from straw and one from cane, was investigated by TGA in air, oxygen, nitrogen, using a heating program simulating the thermal gradient in the gasifiers. Below 400 °C the residues completely burned in air or oxygen with an apparent reaction order of 0.1–0.2. The 75%–80% of the organic mass was pyrolysed at 700 °C, when the gasification with H 2 O and CO 2 started. In the plant tests, the residue was completely converted in gaseous and liquid energy carriers with an overall energy efficiency of up to 87%. Ten conditions were examined with different air flow (19.0, 25.5, 26.5 kg/h), O 2 (4.0, 4.5, 5.5 kg/h) or H 2 O (as steam at 160 °C: 1, 2.5, 4.0, 4.5, 5.5, 8.5 kg/h). The experimental data were analyzed using the Response Surface Analysis (RSA) in order to highlight the dependence on the Equivalence Ratios of oxidation. The molar ratio H 2 /CO in the syngas increased by using steam as co-gasification agent, and reached the value of 2.08 in oxy-steam gasification. Steam was necessary to stabilize the process when using oxygen as it was effective in lowering the average temperature in the gasifier. Another positive effect of using steam was the shift of the temperature maximum far from the grate where ash melting could occur. Oxy-steam gasification provided the best results in terms of syngas heating value (LHV 10.9 MJ/m 3 ) and highest thermal power output of the plant (67 kW th ). The tar yield was inversely correlated with the residence time of the gas in the bed, in according with a zero order reaction for tar cracking into incondensable hydrocarbons and hydrogen.