In this study, compositional analysis of the products obtained by thermal degradation of sugar cane bagasse at various pyrolysis temperatures (300, 350, 400, 450, 500, 550, 600, 650, 700, 750 and 800 °C) and heating rate (5, 10, 20 and 50 °C/min) was studied. Sugar cane bagasse was pyrolyzed in a stainless steel tubular reactor. The aim of this work was to experimentally investigate how the temperature and heating rate affects liquid and char product yields via pyrolysis and to determine optimal condition to have a better yield of these products. Liquid product (bio-oil) obtained under the most suitable conditions were characterized by elemental analysis, FT-IR, C-NMR and HNMR. In addition, column chromatography was employed to determine the aliphatic fraction (Hexane Eluate); gas chromatography and FT-IR were achieved on aliphatic fractions. For char product (bio-char), the elemental chemical composition and yield of the char were determined. The results of our work showed that the amount of liquid product (bio-oil) from pyrolysis of sugar cane bagasse increases with increasing the final temperature and decreases with increasing the heating rate. The highest yield of liquid product is obtained from the samples at 550 °C and at the heating rate of 5°C/min, the maximal average yield achieved almost 32.80 wt%. The yield of char generally decreases with increasing the temperature, the char yield passes from 39.7 wt% to 21 wt% at the heating rate of 5°C/min and from 32 wt% to 17.2 wt% at the heating rate of 50 °C/min at the same range of temperature (300–800 °C). The analysis of bio-oil showed the presence of an aliphatic character and that it is possible to obtain liquid products similar to petroleum from sugar cane bagasse waste. The solid products (bio-char) obtained in the presence of nitrogen (N₂) contain a very important percentage of carbon and high higher heating values (HHV).

Each year, a great quantity of olive oil is produced by the unit mill of trituration. This activity generates two by-products named olive mill wastewater and olive mill solid waste representing major potential waste and environmental problem. However, there is growing interest in pyrolysis as a technology to treat wastes to produce valuable oil, char and gas products. The major important aim of waste pyrolysis is to produce liquid fuel or bio-oil, which is easy to store, transport and can be an alternative to energy source. The key influence on the product yield is the type of biomass feedstock and operating parameters (especially temperature and heating rate). It is important to investigate the effect of variables on response yield and impulse about their optimization. This study reviews operating variable from existing literature on olive mill wastes (OMSW and OMWW) in comparison with various types of biomass. The major operating variables include type of feedstock, final temperature of pyrolysis, heating rate and particle size. The scale of this paper is to analyse the influence of operating parameters on production of pyrolysis bio-oil, char and gaseous products.

This article deals with fast pyrolysis of brown algae, such as Bifurcaria Bifurcata at the range of temperature 300–800 °C in a stainless steel tubular reactor. After a literature review on algae and its importance in renewable sector, a case study was done on pyrolysis of brown algae especially, Bifurcaria Bifurcata. The aim was to experimentally investigate how the temperature, the particle size, the nitrogen flow rate (N₂) and the heating rate affect bio-oil, bio-char and gaseous products. These parameters were varied in the ranges of 5–50 °C/min, below 0.2–1 mm and 20–200 mL. min–1, respectively. The maximum bio-oil yield of 41.3wt% was obtained at a pyrolysis temperature of 600 °C, particle size between 0.2–0.5 mm, nitrogen flow rate (N₂) of 100 mL. min^–1 and heating rate of 5 °C/min. Liquid product obtained under the most suitable and optimal condition was characterized by elemental analysis, ¹H-NMR, FT-IR and GC-MS. The analysis of bio-oil showed that bio-oil from Bifurcaria Bifurcata could be a potential source of renewable fuel production and value added chemicals.

Abstract

This study deals with fast pyrolysis of sawdust wood waste (SWW) at the range of temperature 300–700 °C in a stainless steel tubular reactor. The aim was to experimentally investigate how the temperature, the particle size, the nitrogen flow rate (N₂) and the heating rate affect bio-oil, bio-char and gaseous products. These parameters were varied in the ranges of 5–20 °C/min, below 0.1–1.5 mm and 20–200 mL min⁻¹, respectively. It was concluded that both the temperature and heating rate have a significant effect on both yield of bio-oil and bio-char resulting from pyrolysis of SWW. The liquid products obtained at various pyrolysis temperatures were subjected into column chromatography after removal of asphaltenes (hexane insoluble). Obtained bio-oils (maltenes or hexane soluble) were classified as aliphatic, aromatic and polar sub-fractions. The maximum of bio-oil yield of 39.5 wt% was obtained at a pyrolysis temperature of 500 °C, particle size between 0.5 and 1 mm, nitrogen flow rate (N₂) of 100 mL min⁻¹ and heating rate of 5 °C/min. Liquid product (bio-oil) obtained under the most suitable and optimal condition was characterized by elemental analysis, Nuclear magnetic resonance spectroscopy (¹H NMR and ¹³C NMR), Fourier transformed infrared spectroscopy (FT-IR). The analysis of liquid showed that bio-oil from SWW could be a potential source of renewable fuel production and value added chemical. The yield of char generally decreases with increasing the temperature, the char yield passes from 54.61 to 29.47 wt% at the heating rate of 5 °C/min and from 50.01 to 24.5 wt% at the heating rate of 20 °C/min at the same range of temperature (300–700 °C). Solid products (bio-char) obtained in the presence of nitrogen (N₂) contain a very important percentage of carbon and high heating values (HHVs).

Abstract

In this scientific paper, thermochemical conversion of redwood (RW) was studied. Using the thermogravimetric analysis' technique (TGA), the thermal behavior of RW samples was examined at four heating rates ranging from 5 to 20 K min⁻¹ in inert atmosphere between 300 and 900 K. Two main objectives have been set for this study; the first one was the determination of the kinetic decomposition parameters of RW (Pinus sylvestris L.), and the second one was the study of the variation of characteristic parameters from the TG-DTG curves of the main RW's components, such as; cellulose, hemicellulose and lignin. The kinetic analysis was performed using three isoconversional methods (Vyazovkin (VYA), Friedman (FR) and Flynn-Wall-Ozawa (FWO)), Avrami theory method and the Integral master-plots (Z(x)/Z(0.5)) method to estimate activation energy (E _a ), reaction order (n), pre-exponential factor (A) and model kinetic (f(x)) for the thermal decomposition of cellulose, hemicellulose and lignin components.

The DTG and TG curves showed that three stages identify the thermal decomposition of RW, the first stage corresponds to the decomposition of hemicellulose and the second stage corresponds to the cellulose, while the third stage corresponds to the lignin's decomposition. For the range of conversion degree (x) investigated (0.1 ≤ x ≤ 0.7), the mean values of apparent activation energies for RW biomass were 127.60–130.65 KJ mol⁻¹, 173.74–176.48 KJ mol⁻¹ and 197.21–200.36 KJ mol⁻¹ for hemicellulose, cellulose and lignin, respectively. Through varied temperatures from 550 to 600 K for hemicellulose, from 600 to 650 K for cellulose and from 750 to 800 K for lignin, the corresponding mean values of reaction order (n) were 0.200 for hemicellulose, 0.209 for cellulose and 0.047 for lignin. The pre-exponential factor's average values for three components of RW ranges from 0.08 × 10¹² s⁻¹ to 2.5 × 10¹² s⁻¹ (A _{hemicellulose} = 1.09 × 10¹² s⁻¹), 0.10 × 10¹⁴ s⁻¹ to 0.28 × 10¹⁴ s⁻¹ (A _cellulose = 0.17 × 10¹⁴ s⁻¹) and 3.07 × 10¹⁶ s⁻¹ to 3.69 × 10¹⁶ s⁻¹ (A _lignin = 3.33 × 10¹⁶ s⁻¹), respectively. The experimental data of RW had overlapped the D ₄, D ₂ and F ₃ in the conversion degree of 10–30%, 30–55% and 55–70% for the three components, respectively.

Abstract

In this paper, thermal degradation (TGA) and pyrolysis studies of sunflower shell biomass (SSB), eucalyptus biomass (EB), wheat straw biomass (WSB), and peanut shell biomass (PSB) were carried out using the thermogravimetric analysis and stainless steel tubular reactor. Thermal degradation of all biomass wastes was examined at a heating rate of 10 °C/min in nitrogen atmosphere between 20 and 800 °C. Experiments of pyrolysis were carried out in a tubular reactor from 300 to 700 °C with a heating rate of 10 °C/min, a particle size of 0.1–0.3 mm and nitrogen flow rate of 100 mL.min⁻¹, which the aim to study how temperature affects liquid, solid, and gas products. The results of this work showed that three stages have been identified in the thermal decomposition of SSB, EB, WSB, and PSB wastes. The first stage occurred at 120–158 °C, the second stage, which corresponds to hemicellulose and cellulose's degradation, occurred in temperatures range from 139 to 480 °C for hemicellulose, and from 233 to 412 °C for cellulose, while the third stage occurred at 534–720 °C. It was concluded that temperature has a significant effect on product yields. The maximum of bio-oil yields of 37.55, 30.5, 46.96, and 50.05 wt% for WSB, PSB, SSB, and EB, were obtained at pyrolysis temperature of 500 °C (SSB, PSB, and WSB) and 550 °C (EB). Raw biomass, solid and liquid products obtained were characterized by elemental analysis, Fourier transformed infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR), and x-ray diffraction (XRD). The analysis of solid and liquid products showed that bio-oils and bio-chars from agricultural biomass wastes could be prospective sources of renewable fuels production and value added chemical products.