A Kinetic Study of Marginal Soil Energy PlantHelianthus annuusStalk Pyrolysis

Huaxiao Yan,Hui Zhao,Kechang Xie,Yuanyu Tian,Yan Zhang

doi:10.1155/2013/427049

Huaxiao Yan, Hui Zhao + Show 3 more

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https://doi.org/10.1155/2013/427049

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Abstract

The pyrolytic characteristics and kinetics of new marginal soil energy plantHelianthus annuusstalk were investigated using thermogravimetric (TG) method from 50 to 800°C in an inert argon atmosphere at different heating rates of 5, 10, 20, and 30°C min−1. The kinetic parameters of activation energy and pre-exponential factor were deduced by Popescu, Flynn-Wall-Ozawa (FWO), and Kissinger-Akahira-Sunose (KAS) methods, respectively. The results showed that three stages appeared in the thermal degradation process. The primary devolatilization stage ofH. annuusstalk can be described by the Avrami-Erofeev function(n=4). The average activation energy ofH. annuusstalk was only 142.9 kJ mol−1. There were minor kinetic compensation effects between the pre-exponential factor and the activation energy. The results suggest thatH. annuusstalk is suitable for pyrolysis, and more importantly, the experimental results and kinetic parameters provided useful information for the design of pyrolytic processing system usingH. annuusstalk as feedstock.

Highlights

As potential “ generation” biofuel feedstock, marginal soil plants have attracted considerable attention because of their advantages, such as high photosynthetic efficiency, maximum biomass production, fast growing, high conversion rate, ease of harvesting, and lack of arable soil requirements
According to thermogravimetric (TG) and differential thermogravimetric (DTG) curves of H. annuus stalk (Figures 1 and 2), the results indicated that the pyrolysis process was made up of three stages
Stage II included two zones for H. annuus stalk pyrolysis process: zone I occurred as the temperature increased from T1 to T3 with a maximum mass loss point at T2, and zone II occurred as the temperature increased from T3 to T5 with a maximum mass loss point at T4

Summary

Introduction

As potential “ generation” biofuel feedstock, marginal soil plants have attracted considerable attention because of their advantages, such as high photosynthetic efficiency, maximum biomass production, fast growing, high conversion rate, ease of harvesting, and lack of arable soil requirements. Helianthus annuus can grow well in barren marginal lands and has good resistance to adverse situations. It does not compete with grain crops for arable lands, which is significant for one populous country lack of arable land as China. H. annuus has an excellent adaptability, and the growth cycle is only about 100 days. These characteristics of H. annuus suggest that it can be used as a good potential energy source and should be further studied as a good biofuel feedstock candidate [1,2,3,4,5,6,7,8]

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