论文总字数：37851字

摘 要

生物质能利用的蓬勃发展，对国家能源安全、经济可持续发展和环境保护有着深远的现实意义。尽管生物质能拥有着其得天独厚的优势，但万事都有着两面性，人们对于生物质的开发利用仍然有着不小的阻碍。生物质的分布十分分散，形态万千，并且受季节性影响大，不利于生物质的收集、运输、存储以及利用。生物质热解炭化技术能够高效的将生物质转化为高品质的生物炭，并且能够得到可燃燃气和生物油等高品位能源的副产品，目前在生物质的利用领域受到国内外的广泛关注。本文对玉米秸秆、稻壳和木屑三种生物质原料的热解炭化特性进行了研究。

本文首先选取了玉米秸秆、稻壳、木屑三种生物质作为原料，对原料的基本特性进行了测量，包括元素分析、工业分析和热值测定。然后对三种原料进行了粒径分析和给料标定，再利用热重分析技术对生物质原料热解特性进行了研究，气氛为氮气，升温速率为10℃/min。结果表明，三种生物质原料都有着固定碳含量低、热值低、氧元素含量高、挥发分含量高的特点；三种生物质原料的粒径分布集中在0.25mm-0.83mm之间，三种原料通过调整给料频率以相同的给料速率进料；通过三种生物质原料的热重分析将生物质的热解过程分为干燥预热解、主热解失重、残留物分解炭化三个过程。

在此基础上，本文在搭建的流化床热解炭化实验台上对三种原料在不同温度（400-600℃）及不同氧含量（2%-8%）的气氛下进行热解炭化实验研究。实验结果表明，三种原料随着温度上升，产炭率降低，产气率增加，产油率先升后降。高温有助于产炭燃烧品质的提高，但随着温升促进作用逐渐减弱。随着氧含量的增加，原料热解产炭率产油率均有一定程度降低，产炭的燃烧品质也有所下降。三种原料中木屑产炭的固定碳含量高、灰分含量低，燃烧品质最好，稻壳炭燃烧品质较低但PH值相对更高，相比下更适用于对酸性土壤改良方向的应用。玉米秸秆热解产气较多但可燃气占比不高，产气的热值较低。随着温度升高，热解产气增多，燃气占比也增多，产气燃烧品质更优；随着氧含量增加，热解产气增多，但燃气占比降低，产气燃烧品质降低。

关键词：生物质，热解，热重，流化床，生物炭

Abstract

The vigorous development of biomass energy utilization has far-reaching practical significance for national energy security, sustainable economic development, and environmental protection. Although biomass energy has advantages that other renewable energy sources cannot match, there are also problems such as scattered resources, perishableness, low energy density, difficulty in transportation, and seasonal production. Biomass pyrolysis carbonization technology can efficiently convert biomass into high-quality biochar, obtaining high-grade energy such as flammable gas and bio-oil. Currently, it draws extensive attention in the field of biomass utilization at home and abroad. The pyrolytic carbonization heat of three kinds of biomass materials, including maize stalk, rice husk and saw dust, was studied.

First, three kinds of biomass including maize straw, rice husk and saw dust are selected as raw materials. Then, the basic properties of raw materials are measured, including elemental analysis, industrial analysis and calorific value determination. Next, the particle size analysis and the calibration of the feedstock are performed on three kinds of raw materials. Then the pyrolysis characteristics of the biomass feedstock are studied by using the thermogravimetric analysis technology with the nitrogen atmosphere and the 10°C/min heating rate . The results show that the three biomass raw materials all have the characteristics of low fixed carbon content, low calorific value, high oxygen content, and high volatile content. The particle size distribution of the three biomass raw materials is concentrated between 0.25mm-0.83mm. The three raw materials are fed at the same feed rate by adjusting the feed frequency; the thermogravimetric analysis of the three biomass raw materials divides the pyrolysis process of the biomass into three processes, a dry preheating solution, a main pyrolysis weight loss, and residue decomposition carbonization.

The pyrolysis carbonization experiments of three raw materials under different temperatures (400-600°C) and different oxygen contents (2%-8%) are carried out on a fluidized bed pyrolysis carbonization test bench. The experimental results show that with the increase of temperature, the rate of carbon production decreased, the gas production rate increased, the oil production rate rose first and then decreased in the three kinds of raw materials’ results. The high temperature contributes to the improvement of the char combustion quality, but it gradually weakens as the temperature rise promotion effect. With the increase of oxygen content, the oil production rate of raw material pyrolysis has been reduced to a certain extent, and the combustion quality of carbon production has also declined. Among the three raw materials, the biochar produced from saw dust have high fixed carbon content and low ash content, so they have the best combustion quality. The combustion quality of rice hulls’ biochar was lower but the PH value was relatively higher, which was more suitable for the application of acid soil improvement directions. The pyrolysis of maize straw produces more gas, but the proportion of combustible gas is not high, and the calorific value of gas production is low. With the increase of temperature, the production of pyrolysis gas increases, the proportion of gas increases, and the combustion quality of the produced gas is better. With the increase of oxygen content, the production of pyrolysis gas increases, but the proportion of gas decreases, and the combustion quality of produced gas decreases.

KEY WORDS: Biomass，pyrolysis carbonization，thermogravimetric，fluidized bed，bio-char

目 录

摘要 I

Abstract II

第一章 绪论 1

1.1 课题的研究背景 1

1.2 生物质能利用技术概述 1

1.3 生物质热解炭化技术 2

1.3.1 生物质热解炭化技术简介 2

1.3.2 生物质热解炭化设备研究现状 3

1.3.3 生物质热解炭化的影响因素 5

1.4 本文的研究目的和研究内容 5

1.4.1 本文的研究目的 5

1.4.2 本文的研究内容 6

第二章 实验装置与研究方法 7

2.1 本文所使用的实验装置 7

2.2 本文主要研究方法 8

2.2.1 工业分析 8

2.2.2 热值测定 9

2.2.3 热重分析 10

2.2.4 PH测定 10

第三章 生物质原料特性分析 11

3.1 生物质原料的预处理和初步分析 11

3.1.1 生物质原料的预处理 11

3.1.2 生物质原料的工业分析、元素分析及热值测定 11

3.2 生物质原料的粒径分析 12

3.3 生物质原料给料标定 13

3.4 生物质原料的热重分析 15

3.5 本章小结 17

第四章 流化床热解实验研究及产物分析- 18

4.1 实验方法 18

4.2 生物质物料种类对生物质热解的影响 18

4.2.1 物料种类对三相产物分布的影响 18

4.2.2 物料种类对产物生物炭品质的影响 21

4.2.3 物料种类对产气的影响 24

4.3 热解温度对生物质热解的影响 26

4.3.1 热解温度对三相产物分布的影响 26

4.3.2 热解温度对产物生物炭品质的影响 27

4.3.3 热解温度对产气的影响 32

4.4 流化风氧含量对生物质热解的影响 33

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