Influence of Process Parameters on Synthesis of Biochar by Pyrolysis of Biomass: An Alternative Source of Energy

Abstract

Organic matter derived from plants and animals are known as biomass. It has a great potential to be used as an alternate source of energy by employing thermochemical conversion techniques. Among the available techniques, pyrolysis is considered to be the most efficient technique used for the conversion of biomassbased waste into value-added solid, liquid and gaseous products through heating in an oxygen-limited environment. Biochar (solid fuel) is a carbonaceous material and has multiple applications in various fields such as soil health, climate stability, water resource, energy efficiency and conservation. The yield of biochar depends on organic constituents of biomass and the pyrolytic process parameters such as temperature, time, heating rate, purging gas, particle size, catalyst, flow rate, pressure and types of pyrolysis reactors. Suitable conditions for biochar production were observed to be slow pyrolysis, low carrier gas flow rate, acid-catalysed biomass or biomass mixed with some inorganic salts, low heating rate, large particle size, high pressure, longer residence time, low temperature, feedstocks with high lignin content and pyrolysis reactors with lower bed height. Thermal conversion of biomass could be a possible sustainable alternative to provide economically viable, clean and eco-friendly solid fuel.

Green Synthetic Fuels: Renewable Routes for the Conversion of Non-Fossil Feedstocks into Gaseous Fuels and Their End Uses

“…The pyrolysis process can be divided into three subclasses depending on the operating conditions: Conventional or slow pyrolysis: the process is characterized by an operating temperature of nearly 500 • C, a low heating rate (0.6-6.0 • C/min) and a long residence time (5-30 min) [473]. These conditions allow the repolymerization reaction to maximize char production.…”

Optimization of process and properties of biochar from cabbage waste by response surface methodology

“…Pyrolysis was conducted at a ramp rate of 5°C min −1 and a hold duration of 15 min using a muffle furnace (Lindberg Blue M-3504, Thermo Scientific) to produce biochar following the CCD structure (Table 2). These pyrolysis conditions result in high yields and suitable properties for soil amendments [17,19].…”

“…The conditions for pyrolysis, such as temperature, particle size of biomass, shape, holding time, and heating rate, have a significant influence on the structural and physicochemical properties of biochar [16,17]. Temperature is the most influential parameter, as it drives the degree of carbonization and elemental changes.…”

“…Particle size has been demonstrated to impact yield [16] as well as various biochar properties such as elemental composition, specific pore volume, surface area, electrical conductivity, and surface functional groups [19], while we were unable to find any studies relating to the effect of biomass quantity. It is quite possible that the larger particle size and quantity of biomass may hamper heat transfer during pyrolysis, particularly in fixed bed systems, and ultimately this may result in a reduced carbon content of char [17]. Keeping these aspects in view, a preliminary investigation is required at laboratory scale to find out the most suitable pyrolysis temperature, particle size, and quantity of biomass to produce best char suitable for soil amendment.…”

Development of a Thermochemical Conversion Unit for Corn Residues

“…The highest obtained bio-char was 24% at 38 L/s airflow and without heater settings. 26) . Operating without a heater therefore produces higher bio-char than using it.…”