Thermochemical Conversion of Biomass for Syngas Production: Current Status and Future Trends

Abstract

The thermochemical conversion of different feedstocks is a technology capable of reducing the amount of biowaste materials produced. In addition, the gasification of feedstock using steam as a gasifying agent also produces hydrogen, which is a clean energy fuel. This article aimed to encapsulate the current status of biowaste gasification and to explain, in detail, the advantages and limitations of gasification technologies. In this review paper, different gasifying agents such as steam, air, and oxygen, as well as their effects on the quality of syngas production, are discussed. In addition, the effects of reactor configuration and different operating parameters, such as temperature, pressure, equivalence ratio, and incorporation of a catalyst, as well as their effects on the ratio of H2/CO, LHV, syngas yield, and tar production, were critically evaluated. Although gasification is a sustainable and ecologically sound biomass utilization technology, tar formation is the main problem in the biomass gasification process. Tar can condense in the reactor, and clog and contaminate equipment. It has been shown that an optimized gasifier and a high-activity catalyst can effectively reduce tar formation. However, key biowaste treatment technologies and concepts must first be improved and demonstrated at the market level to increase stakeholder confidence. Gasification can be the driving force of this integration, effectively replacing fossil fuels with produced gas. In addition, support policies are usually needed to make the integration of biomass gasification technology into the industry profitable with fully functional gasification plants. Therefore, to address such issues, this study focused on addressing these issues and an overview of gasification concepts.

Biochar: Production, Application and the Future

“…Partial oxidation of biomass, unlike combustion, takes the energy available in the biomass and bundles it into chemical bonds in the form of gaseous products. The intrinsic chemical energy of carbon in biomass is transformed into combustible fuel gases, which are more efficient and convenient to utilize than raw biomass [54]. Commercial use of the gasification technique has also been documented.…”

Hydrogen, Ammonia and Symbiotic/Smart Fertilizer Production Using Renewable Feedstock and CO2 Utilization through Catalytic Processes and Nonthermal Plasma with Novel Catalysts and In Situ Reactive Separation: A Roadmap for Sustainable and Innovation-Based Technology

“…In recent years, there has been a concerted drive for the techno-economic feasibility, life cycle and environmental impact assessments of bioenergy from various types of biomass and biomass waste and the means of achieving the most efficient biomass-to-energyand-chemicals conversion [67,[99][100][101][102][103][104][105][106][107][108][109][110][111][112][113][114][115]. These studies show that bioenergy with carbon capture and storage (BECCS) has the potential to limit global warming by providing net negative greenhouse gas emissions [100][101][102][103][104][105][106][107][108][109][110]. In biomass-to-chemicals conversion, including ammonia production and in bioenergy applications, hydrogen is always the limiting chemical.…”

Syngas Production from Biomass Gasification: Influences of Feedstock Properties, Reactor Type, and Reaction Parameters

“…According to Chan et al, 20 a high ash content reduces char production and thus syngas production, as well as particulate emissions that need to be eliminated by downstream gas cleaning procedures. According to Maitlo et al, 21 high ash levels in biomass can cause issues like catalyst sintering and reactor blockage during the gasification process. As the amount of ash in poultry manure rises from 17.2% to 25.1%, the content of alkali metals and Si elements in the biomass also increases, which results in a lower ash melting point and a high risk of molten slag formation on the exterior of agglomerated particles.…”

“…On the one hand, rising temperatures promote the endothermic gasification process, which increases the yield of syngas. On the other hand, higher temperatures promote the heat absorption reaction in the tar cracking reaction, resulting in lower tar content and the formation of H 2 , CO, and CO 2 21 and raising gas yield. Mallick et al 56 analyzed the performance of a circulating fluidized bed gasifier using wood chips (SD), rice husks (RH), and bamboo chips (BD) as feedstock.…”