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This work aimed to study the effect of gasification process operating conditions on syngas composition and properties, and process efficiency. A rotary kiln gasifier lab-scale pilot plant with capacity ≅ 30 kg/h and a power of 30 kWe was used for gasification tests applied to cherry wood at different loads, for a temperature of about 600°C, while the air was used as gasification agent for all tests. The syngas composition was measured and analyzed. The results have shown that conversion of wood cherry through gasification lead to a lean fuel gas of 3.5 MJ/Nm3 and installation characteristics have a major influence both on process and syngas properties. This is happened because the rotary kiln gasifier allows some air infiltrations, and consequently a high N2 content in the syngas composition. The energy balance of the cherry biomass gasification processes was calculated. It was found also that gas density varies slightly from 1.26 to 1.43 kg/m3, while the specific heat of the gas varies from 1.04 to 1.34 kJ/kgK.

At present, the principles of sustainable development are being implemented in almost all economy sectors whereas one of the key drivers of the transition to a new concept is higher education system also. The inclusion of special academic disciplines on sustainable development, the implementation of environmental protection measures, financial support for research in the field of environmental sciences, campuses landscape – all these stimulates the process of transition to a concept of sustainable development. In addition, higher education makes it possible to form an ecological worldview among the younger generation that is an effective tool in achieving sustainable development goals (SDGs). University graduates who understand the need to achieve the SDGs and provide environmental protection, lead an eco-friendlier lifestyle and pass on the knowledge they have gained to their children or other family members. The purpose of this study is to analyze the relationship between the involved activity of universities in the field of sustainable development and the implementation of large-scale government programs to achieve environmental sustainability. The study will examine the experience of Eu and non-EU universities and state environmental protection programs. The results obtained allow us to conclude about the correlation between educational activities in the higher education system and achievements at the state level of environmental sustainability.

The paper presents the experimental results of Food Court Waste air gasification using a batch reactor. This type of waste is generated mainly in the food court areas of services spaces, shopping centers, airports and malls and is generally composed of paper & cardboard, plastic, organic, wood, metal and glass waste. The process operating parameters were: temperatures between 650°C and 850°C and an equivalent ratio of 0.25 and 0.4 respectively. The study focused on the influence of process parameters on the energy conversion rate considering the cold gas and hot gas efficiency correlated with the feedstock carbon conversion rate. The recorded instantaneous concentrations of sampled gas species were plotted in time dependent graphs for accurate variation curves of gases concentrations. The results can be used to isolate the startup stage of the gasification process and to establish the optimal process parameters for increased overall energy efficiency. In conclusion, considering the current setup, operational parameters and process energy efficiency, the optimal temperature for the air gasification of Food Court Waste is 850ºC with an equivalent ratio of 0.40.

The purpose of this work was to study the gas yield variation resulted from the cherry wood gasification with air using a lab-scale rotary kiln gasifier. The feedstock was continuously fed into the preheated reactor at 600°C, in co-current configuration, using atmospheric air as a gasifying agent. The results indicate the importance of oxidation reaction control, through the feeding flow rates of biomass and air and the reactants mixing rate. From the experiment, the hydrogen yields were about 2-4%, while the carbon monoxide varied between 8-21%. Additionally, the paper provides process observations based on the continuous monitoring of gas composition. The specific flow rates of substances and installation operating conditions were linked to process run through syngas composition.

In 2015 the European Commission issued a package of documents on Circular Economy concerning an integrated revision of legislative proposals on waste management. The aim was to stimulate a European transition towards a circular economy concept, which is expected to foster competitiveness, sustainable economic growth and new jobs generation. Three indicators are proposed in this paper to contribute to the assessment of the energy recovery management performance from MSW in a scenario of circular economy: a) referring to MSW directly used (RMSW) or indirectly used (SRF) as input of thermochemical plants, an indicator can be the percentage of waste having LHV > 13MJ/kg; b) referring to the MSW directly or indirectly used as input of thermochemical plants, the percentage of waste having ash recovered; c) referring to food waste, percentage of this stream sent to anaerobic digestion. The above indicators, proposed and discussed in this paper, have to be integrated with other ones in order to complete the quantification of the role of MSW management in term of energy recovery under a circular economy strategy. It is not the aim of the present paper to give a comprehensive solution to this complex issue.

Using different gasification agents: air and steam, two types of gasification process were performed into a batch reactor at temperature of 750°C and 850°C and atmospheric pressure. The only difference between of the two compared experimental configurations was represented by the gasification agent used in the process. The amount of oxygen introduced into the reactor for air gasification at an ER of 0.3 was computed. Therefore, in the steam gasification process, the same amount of oxygen was introduced, so establishing an unordinary steam to biomass ratio. In this way, the two processes, air vs. steam gasification, were compared, the rest of the process parameters being kept constant. This paper approaches the transitory regimes (initiation stage) of gasification process in order to observe the influence of process temperature and gasification agent on the process run. According to the experimental results, better gas quality is obtained if steam is used as a gasifying agent, yet the conversion and energy efficiencies decreases. By optimizing time residence in steam gasification, process efficiencies may be increased.

The results presented in the following paper are making the aim of a broadly research concentrated to investigate the temperature effects on agricultural waste pyrolysis performed in a batch reactor. Briefly, the motivation along with experimental features and main results generated from the rape straw low temperature pyrolysis (300°C-500°C) have been offered in the first part submitted at the MSE 2019 conference, with the title: Bio-gaseous fuels from agricultural waste pyrolysis (Part I). The current section (second part of the study) presents the results obtained in case of the rape straw high temperature pyrolysis (600°C-800°C). Overall, as expected, the augmentation of the operating temperature, inhibits the bio-oil and biochar formation, enhancing the pyrolysis gas production. The distribution of gaseous components varies depending on temperature and residence time. The transition stages and the formation of the main pyrolysis gaseous species are also presented and discussed. The most dominant chemical element from the pyrolysis gas is N2, due to its constant presence as non-oxidant agent in the process. Considering the same premise, the rape straw pyrolysis gaseous species distribution in the temperature range of 600°C-800°C varies between: 47%-58% CO2, 18%-28% CO, 14%-35% H2, while the pyrolysis gas density 1.1-1.4 kg/m3 and higher heating value 23-52 MJ/kg.

The present research proposes two scenarios for the biomass conversion into valuable products within the integrated management of bio-resources. The scenarios have been developed considering: the biomass availability, material and by-products characteristics and the comprehensive combination of the primary technologies used for the conversion of the biomass mixtures into energy. In scenario 1 the biomass waste valorisation is made via integrated pyrolysis and combustion treatment, while in scenario 2 the biomass conversion in done considering the integration of the pyrolysis, gasification and combustion treatments into the conversion chain. The results revealed that all analysed scenarios purposed are self-independent from the energetic point of view.

The study, presented in two parts, puts in discussion the experimental results of low and high temperature pyrolysis on agricultural residues using a tubular batch reactor. During the experiment, nitrogen was used both as reaction environment and gas products carrier. The work focusses mainly on the pyrolysis gas analytical composition resulted from the process. The first part of the research is dedicated to the effect of process low temperature on rape straw pyrolysis. The experiments were conducted at 300°C, 400°C and 500°C to observe the solid – gas transformation at relative low temperatures. The main results revealed that, by balancing the amount of the nitrogen, the rape straw pyrolysis gas distribution varies by average between: 72%-77% CO2, 22%-24% CO, 1%-4% H2. The density of the gas in the devolatilization stage varies by average between 1.6-1.7 kg/m3, while its higher heating value ranges from 4 MJ/Nm3 - 8 MJ/Nm3.