Analysis of Bio-Oil, Biogas, and Biochar from Pressurized Pyrolysis of Wheat Straw Using a Tubular Reactor

Abstract

The main objective of this work was to examine the influence of pyrolysis pressure on product yield from wheat straw pyrolysis. The experiments were performed in a tubular reactor at different pressures (10, 20, 30, and 40 psi) with a constant flow rate of nitrogen (50 cc/min) at a temperature of 500 °C. During pyrolysis, the products obtained are oil, gas, and char. The maximum oil yield was 37.6%, obtained at high pressure (40 psi). Liquid product was analyzed using gas chromatography/mass spectrometry (GC-MS). The percentage of bio-oil compounds increased as operating pressure increased. The major components present in the bio-oil were phenols, methoxyphenols, and substituted methoxyphenols such as eugenol and vanillin. The gas products were mainly CO, H 2 , CO 2 , CH 4 , C 2 H 4 , C 2 H 6 , C 4 H 10 , and C 3 's. Char characteristics were measured using scanning electron microscopy (SEM) and ultimate analysis. Van Krevelen diagram shows that the chars obtained from wheat straw pyrolysis have very less H: C and O: C ratios than the raw wheat straw. On the basis of the results of this study, it may be concluded that, within the pressure range studied, 20 psi is the optimum pressure for the pyrolysis of the wheat straw in a tubular reactor with respect to products (char, bio-oil, and gas) yield.

Characterization of energy carriers obtained from the pyrolysis of white ash, switchgrass and corn stover — Biochar, syngas and bio-oil

“…Furfural, D-allose and phenolic compounds are the main chemical compounds in the bio-oil for the three kinds of biomass. Similar results were reported in our previous research [23,32] and the work of Mahinpey [5]. Properties and chemical composition of bio-oil are distinct from petroleum fuel because of its relatively high content of water and solids, acidity and instability when heated [26].…”

“…It can be seen in Tables 3-5 that 30, 25 and 22 kinds of chemical compounds were detected from white ash, switchgrass and corn stover bio-oils, respectively. It has been reported that bio-oils produced from different types of biomass samples under similar conditions have similar composition [5]. Table 3 shows that the white ash bio-oils (300°°C, 400°°C and 500°°C) had a large amount of compounds including furfural (relative mol contents were 10.15%, 14.97%, 12.35%, respectively), Butyrolactone (relative mol contents were 8.15%, 8.10%, 6.58%, respectively), metacetamol (relative mol contents were 8.36%, 11.70%, 8.11%, respectively) and D-allose (relative mol contents were 5.68%, 11.46%, 10.19%, respectively).…”

“…In general terms, with its relatively high content of water and oxygen, bio-oil is acidic and not stable when heating, and its heating value lower than petroleum. Bio-oil is easy to transport, making biomass a dominant choice for the replacement of fossil fuels [5]. Its use as fuel in boilers and engines has been tested [6,7].…”

Review Paper: The Fundamentals of Biochar as a Soil Amendment Tool and Management in Agriculture Scope: An Overview for Farmers and Gardeners

“…In addition to traditional pyrolysis procedures for biochar generation, alternate methods have been discovered. Comprises: 1) pressurized pyrolysis [82]; 2) hydrothermal carbonization [83] [84] [85]; 3) microwave pyrolysis [86]. These latter procedures have potential as ways to resources with properties external the range of usual pyrolysis products and greater energy efficiency.…”

Physico-Chemical Properties of Bio-Oils from Pyrolysis of Lignocellulosic Biomass with High and Slow Heating Rate

“…Most of the compounds identified through in the bio-oils originated due to the thermal cracking of cellulose, hemicellulose and lignin in the biomass. Numerous amounts of compounds were identified in the bio-oils (Mahinpey, Murugan, Mani, & Raina, 2009). Due to their diversity, they were categorized into five major classes, namely monoaromatics, polyaromatics, aliphatics, oxygenates and nitrogenates.…”