Abstract
Rice straw gasification was carried out in a laboratory fluidized bed reactor system from 600 to 800 °C in order to well-understand the release and occurrence mode of alkali metals as a function of temperature during the gasification process. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was applied to analyze the original rice straw and obtained fly ash at different temperatures. The results show that the Water-Soluble, Ammonium acetate-Soluble, Hydrochloric acid-Soluble, and Aluminosilicate Combination-Soluble modes of the Na and K contents in rice straw decreased in sequence. The content of Water-Soluble salts of Na and K accounts for more than 50%, while the content of the Aluminosilicate Combination-Soluble mode is the lowest: less than 5%. The release rate of Na appears to be consistent but nonlinear, increasing with gasification conversion ranges between 50.2% and 70.8%, from which we can deduce that temperature is not the only factor that impacts Na emission. The release of K can be divided into two stages at 700 °C. At the first stage, the release rate of K is almost invariable, ranging from 23.3% to 26%. At the second stage, the release rate increases sharply: up to 55.9%. The concentration and the proportion of the Water-Soluble, Ammonium acetate-Soluble, and Hydrochloric acid-Soluble modes of Na in fly ash decrease with a temperature increase. The release of K can be explained as follows: one path is an organic form of K converted into its gaseous phase; the other path is a soluble inorganic form of K that is volatile at a high temperature. With a temperature increase, the Aluminosilicate Combination-Soluble mode of both Na and K increases.
Highlights
Besides solar and wind energy, biomass is considered to be a main renewable energy source, which can be used as adjustable, controlled energy in a renewable energy mixture of solar, wind, and biomass energy
As a key technology for biomass utilization, biomass gasification represents an efficient process for the production of power and heat and the production of hydrogen and second-generation biofuels
Gasification can theoretically convert all different types of biomass into syngas, which is mainly composed of hydrogen, carbon monoxide, carbon dioxide, and methane, for use as gas fuel and raw
Summary
Besides solar and wind energy, biomass is considered to be a main renewable energy source, which can be used as adjustable, controlled energy in a renewable energy mixture of solar, wind, and biomass energy. There are far less geographical restrictions for biomass production in most non-desert countries, so biomass utilization is an important part of national energy security for non-OPEC (non-Organization of Petroleum Exporting Countries) countries. The energy supply derived from biomass keeps growing, while that from wind and solar is still at a low level [1]. As a key technology for biomass utilization, biomass gasification represents an efficient process for the production of power and heat and the production of hydrogen and second-generation biofuels. Gasification can theoretically convert all different types of biomass into syngas, which is mainly composed of hydrogen, carbon monoxide, carbon dioxide, and methane, for use as gas fuel and raw
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
