Renewable Energy for Sustainable Growth Assessment. Группа авторов
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Название: Renewable Energy for Sustainable Growth Assessment

Автор: Группа авторов

Издательство: John Wiley & Sons Limited

Жанр: Физика

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isbn: 9781119785446

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СКАЧАТЬ Co-digestion under mesophilic and thermophilic conditions Biogas Semi-continuous reactors for acclimation and batch reactors for co-digestion [78] Sewage scum Lipids extracted by solvent-less separation from wet sewage scum Direct esterification Biodiesel (Fatty acid methyl esters (FAMEs)) Three sequential batch reactors using a counter-current flow of reactants [79]

      Worldwide biomass assets and the latest state-of-the-art in the biomass conversion process were reviewed by Xu et al. [7] viz., thermochemical and biological conversion process, including torrefaction and carbonization, pyrolysis, gasification, combustion, and anaerobic digestion and also reported on their technological and large-scale challenges.

       3.3.2.1 Thermochemical Conversion

      Thermochemical processes of transformation were carried out at various temperatures by multiple types; torrefaction and carbonization, rapid pyrolysis, gasification, and combustion [5]. For thermochemical conversion, proper temperature, pressure, and heating rate are essential. Nitrogen oxides (NOx), particulate matter (PM), and tar are released from biomass by thermochemical conversion [80]. Existing methods have virtually eliminated NOx and PM emissions, while tar has been minimized by definitive treatment and in situ process management.

      3.3.2.1.1 Torrefaction and Carbonization

      Torrefaction is a low-temperature (under 400 °C) process of biomass and bio-solid pyrolysis that results in bio-coal, charcoal, and torrefied production biomass. This method creates energy carriers with hydrophobic properties and high calorific content. When heated to high temperatures in an inert environment, Biomass converts carbon-based energy-rich in carbon by carbonization. However, an outdated method is still in usage as it paves the way for commercialization and scientific implementation [81]. Hydrothermal carbonization is a promising technology for complete wastewater treatment without the dryness process and any discharge of waste. Often it is carried out at high pressure or moderate temperatures in the presence of water [5]. This conversion process yields carbon-rich hydrochar, solid fuel with high-density material, and process water with high organic content [75]. Even at low temperatures, Torrefaction extracts chlorine from biomass that induces metal corrosion when treated by combustion or gasification processes [82].

      3.3.2.1.2 Pyrolysis

      To turn biomass into energy products (bio-oil, stable biochar, and pyrolytic gas), employed pyrolysis as a dynamic thermochemical method carried between 400 °C and 700 °C [85]. The properties of pyrolysis products are significantly evaluated by temperature, whereas the heating rate specifies the type of biomass pyrolysis that is either fast or slow. In the absence of O2, slow pyrolysis carried out at an extended period and optimized temperature results in maximum biochar yield compared to rapid pyrolysis [86]. Biochar can be used in boilers, as a catalyst, as an adsorbent, and in other manufacturing processes as solid fuel. For internal combustion engines and other techniques, pyrolytic gas may be a sustainable alternative fuel [85, 86]. Currently, the Life Cycle Assessment (LCA) approach evaluates the environmental effects of fuel combustion, electricity production, eutrophication, and N fertilizer synthesis from agricultural biomass in Shandong’s northern area in China [87]. They claimed in the study that the distributed-centralized agricultural straw pyrolysis (DCP) system was both socially and economically more advantageous for managing the disposal of crop residues compared to the traditional straw incorporation biprocess.

      3.3.2.1.3 Gasification

      Biomass gasification is accomplished by thermochemical reactions between 700 °C and 900 °C with high potential applications. Low-cost biomass and urban solid waste to gasify biomass for electricity generation [88]. Guran [89] showed that syngas production through gasification could be a sustainable resource of alternative fuel or converted as liquid fuels and chemicals.

      3.3.2.1.4 Combustion

      Combustion is a process of thermochemical reaction carried above 900 °C that releases energy in the form of heat and bioenergy products. Direct combustion produces carbon-rich solid fuels, liquid hydrocarbon materials, gaseous fuels, and the immediate release of all energy through the thermochemical conversion process [90].

       3.3.2.2 Biological Conversion

      Biological conversion is the biomass conversion method by the mechanism of anaerobic digestion, fermentation, or composting using enzymes from bacteria or other microorganisms [9].

      3.3.2.2.1 Anaerobic Digestion (AD)

       3.3.2.3 Advanced Technology for Biomass Conversion

      Current advanced technology for biomass conversion includes BIGCC (biomass integrated gasification combined cycle) systems, co-firing (coal including gas), combined heat and power (CHP), transesterification, and cellulosic biomass conversion [93].

      3.3.2.3.1 Biomass Integrated Gasification Combined Cycle (BIGCC)

      The BIGCC is the most effective and advanced technique for transforming biomass energy into biofuel from all biomass, such as urban waste, wood residues, and agro-food byproducts [94]. The BIGCC plant designed in a planned design focused on electricity and energy balances. With the rise of both pressure and temperature ratios and the increased firing of biomass, the efficiencies СКАЧАТЬ