Properties of bio-oil and bio-char produced by sugar cane bagasse pyrolysis in a stainless steel tubular reactor

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)

A review on thermochemical treatment of biomass: Pyrolysis of olive mill wastes in comparison with other types of biomass

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

Thermochemical treatment of olive mill solid waste and olive mill wastewater Pyrolysis kinetics

In olive-oil-producing countries, large amounts of waste material are generated as by-product for which there is no ready use and in some cases may have a negative value because of the cost of disposal. Most of these countries depend on fossil fuels for their energy uses, and olive mill wastes can be used to supplement such energy sources using thermochemical conversion processes such as pyrolysis. However, efficient operation of thermochemical conversion systems requires a thorough understanding of the influence of the composition and thermal properties of these by-products on their behaviour during the conversion process. In this study, the thermal behaviour of two olive mill wastes samples (olive mill solid waste: OMSW, and concentrated olive mill wastewater: COMWW) was examined at different heating rates ranging from 5 to 50 A degrees C min(-1) in inert atmosphere using the technique of thermogravimetric analysis. As the increment of heating rates, the variations of characteristic parameters from the TG-DTG curves were determined. The initial temperature of degradation is higher in OMSW, which present a high amount of cellulose in comparison with COMWW. Three methods were used for the determination of kinetic reaction parameters: Friedman, Ozawa-Flynn-Wall and Vyazovkin methods. The results showed that apparent activation energy obtained for the decomposition of hemicelluloses and cellulose derived from OMSW was given as 150-176 and 210.5-235.7 kJ mol(-1), while for COMWW, the values were 133-145 and 255-275 kJ mol(-1), respectively

Thermal degradation and kinetic studies of redwood (Pinus sylvestris L.)

In this scientific paper, thermochemical conversion of redwood (RW) was studied. Using the thermog- ravimetric 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 (Ea), 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 3 1012 s-1 to 2.5 3 1012 s-1 (Ahemicellulose 5 1.09 3 1012 s-1 ), 0.10 3 1014 s-1 to 0.28 3 1014 s-1 (Acellulose 5 0.17 3 10 14 s-1 ) and 3.07 3 10 16 s-1 to 3.69 3 10 16 s-1 (Alignin 5 3.33 3 10 16 s-1 ), respectively. The experimental data of RW had overlapped the D4, D2 and F3 in the conversion degree of 10–30%, 30–55% and 55–70% for the three components, respectively