Vol 3, No 2 (2020)

Table of Contents

Open Access
Article
Article ID: 1499
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by Rui Ma, Ze Wang, Lu He, Wenli Song, Songpo Zhang
Therm. Sci. Eng. 2020 , 3(2);    623 Views
Abstract The regularity and variability of the composition distribution of the pyrolysis products of corn stover fermentation residue and phenolic resin with the pyrolysis temperature were investigated by thermogravimetry (TG) and lyser-gas/mass spectrometer (Py-GC/MS). The results show that toluene, phenol and methyl phenol are  the main common components of the two systems, 2,3-dihydrobenzofuran, alkoxy compounds and a small amount of carboxylic acid are  the unique components in the pyrolysis products of corn straw fermentation residue, while dimethyl phenol, 9H-xanthene and other components in the phenolic . This is a reflection of the differences in the composition and structure of the two raw materials.
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Open Access
Article
Article ID: 1500
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by Danilo Figueroa, Anderson Moreno, Angelina Hormaza
Therm. Sci. Eng. 2020 , 3(2);    433 Views
Abstract Adsorption is a widely used method for the treatment of dissolved contaminants. Various agro-industrial wastes have been explored as potential adsorbents, showing high efficiency in dye removal. Each adsorbate-adsorbent pair needs kinetic, and equilibrium models to scale up this process. In this work, the equilibrium, kinetics and thermodynamics of the corn Tuza-Red 40 system were evaluated under batch system at ph = 2.0 at temperatures of 25, 40, and 55 °C. The Langmuir, Freundlich and Temkin models were selected for the isotherm representation, while the Lagergren, Ho, and Elovich equations for the kinetics of the process. The Freundlich model presented the best fit to the isotherms, the adsorption kinetics was best described by the Ho equation, and the values for Gibbs free energy and entropy indicated the spontaneity and feasibility of the process.
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Open Access
Article
Article ID: 1501
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by Sen Xiao
Therm. Sci. Eng. 2020 , 3(2);    616 Views
Abstract Quartz sand was used as bed material in a small fluidized bed reactor with 1 kg/h feed. Corn straw powder with particle size of 20–40 mesh, 40–60 mesh, 60–80 mesh and 80–120 mesh was used as raw material for rapid pyrolysis at reaction temperatures of 400 °C, 450 °C, 500 °C and 550 °C. The bio-oil obtained after liquefaction of pyrolysis gas was analyzed. The variation trend of bio-oil composition in pyrolysis of corn straw powder with different reaction temperatures and raw material sizes was compared. The results show that: (1) the content of 3-hydroxyl-2-phenyl-2-acrylic acid in bio-oil increases with the decrease of raw material particle size, but it is less at 450 °C; (2) with the increase of reaction temperature, the content of hydroxyacetaldehyde in bio-oil increases at first and then decreases: the content of hydroxyacetaldehyde in bio-oil is the highest at 500 °C when the particle size is 20–40 mesh, and the highest at 450 °C with the other three particle sizes. Compared with other particle sizes, raw material with the particle size of 60–80 mesh is not conducive to the formation of aldehyde compounds; (3) the reaction temperature of 500 °C and the particle size of 60–80 mesh of raw materials are more conducive to the formation of phenolic compounds in bio-oil; (4) the ester compounds with particle size of 20–40 mesh in bio-oil is 20% higher than that of other particle sizes; (5) the reaction temperature and the particle size of raw materials had no significant effect on the formation of ketones, alcohols and alkane compounds in bio-oils.
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Open Access
Article
Article ID: 1502
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by Jorge Jadid Tamayo-Pacheco, José Ramón Copa-Rey, Manuel Cantos-Macías, Angel Luis Brito-Sauvanell, José Luz Silveira
Therm. Sci. Eng. 2020 , 3(2);    462 Views
Abstract Plasma thermal gasification can be one of the most relevant and environmentally friendly technologies for waste treatment and has gained interest for its use in thethermos-conversion of biomass. In this perspective, the objective of this study is to evaluate the gasification of sugarcane bagasse by studying the effective areas of operation of this process and to establish a comparison with conventional autothermal gasification. A thermochemical equilibrium model was used to calculate the indicators that characterize the performance of the process on its own and integrated with a combined cycle. As a result, it was obtained that plasma and gasification of bagasse is technically feasible for the specific net electrical production of 4 MJ with 30 % electrical efficiency, producing a gas with higher calorific value than autothermal gasification. The operating points where the electrical energy production and the cold gas efficiency reach their highest values were determined; then the effects of the operational parameters on these performance indicators were analyzed.
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Open Access
Article
Article ID: 1504
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by Kehong Wang, Daiqing Zhao, Lin Lin, Wei Wang
Therm. Sci. Eng. 2020 , 3(2);    621 Views
Abstract Two kinds of solar thermal power generation systems (trough and tower) are selected as the research objects. The life cycle assessment (LCA) method is used to make a systematic and comprehensive environmental impact assessment on the trough and tower solar thermal power generation. This paper mainly analyzes the three stages of materials, production and transportation of two kinds of solar thermal power generation, calculates the unit energy consumption and environmental impact of the three stages respectively, and compares the analysis results of the two systems. At the same time, Rankine cycle is used to compare the thermal efficiency of the two systems.
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Open Access
Review
Article ID: 1503
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by Chuangzhi Wu, Xiuli Yin, Huacai Liu, Yong Chen
Therm. Sci. Eng. 2020 , 3(2);    459 Views
Abstract Distributed biomass energy technology has strong adaptability to the types of raw materials, flexible project scale, can meet the needs of special users, better economy in small scale, easier commercial development, in line with the characteristics of biomass resources and China’s national conditions. The distributed utilization of biomass energy mainly includes biomass briquette fuel and biogas. The key technologies include biomass briquette fuel processing and combustion, large and medium-sized biogas engineering technology, biomass gasification pyrolysis and gas utilization. At present, China’s distributed biomass energy technology is mainly in the stage of technological improvement and application demonstration. It is expected that by 2030, most of the key technologies will be basically mature and have the conditions for industrialization. The main development direction of China’s distributed biomass energy industry is the replacement of traditional coal-fired gas, urban/rural clean living energy supply, and rural ecological environmental protection. The pollution caused by burning coal/fuel oil, and at the same time centering on the national new urbanization strategy, provide sustainable clean energy for the construction of new rural areas, and improve the level of rural ecological and environmental protection. At present, the main bottleneck restricting the development of distributed biomass energy industry is economy and reliability. The state should increase investment in technological innovation and policy support, convert the environmental and social benefits of biomass energy into cost benefits, and promote biomass energy. The development of the industry can be distributed and utilized.
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