制备条件对低品质生物质半焦燃烧特性的影响

EFFECT OF THE PYROLYSIS CONDITIONS ON COMBUSTION HARACTERISTICS OF LOW-QUALITY BIOMASS CHAR

研究利用热重分析仪考查不同制备条件(热解温度、热解升温速率、热解气氛)下制得的低品质生物质废物(鸡粪与猪粪)半焦的燃烧特性,并考察其中的矿物质组分对半焦燃烧性能的影响。结果表明:鸡粪半焦较猪粪半焦燃烧性能更好;制备条件不同,所制半焦的燃烧特性不同;制焦过程中,升温速率的提高及水蒸气气氛均能提高禽畜粪便半焦的燃烧性能;禽畜粪便中矿物质组分对其半焦的反应性能具有极大的促进作用;随着制焦温度的升高,猪粪半焦的燃烧性能呈先增强后减弱的趋势。

The low-quality biomass can be converted into syn-gas or hydrogen quickly by low temperature catalytic steam gasification. The biomass char combustion can supply energy for the gasification process. In the paper, the effect of the preparation conditions （ heating rate, final temperature and preparation atmosphere） on the combustion characteristics of the chars derived from hen and pig manures was addressed. The two manures were first pretreated by dilute HC1 and HF acid washing and the combustion behaviors of the chars, which was prepared from the manure samples before and after pretreatment under different pyrolysis conditions using a tubular fixed bed reactors, were investigated using TG analyzer. The effect of the minerals contained in the manures on the combustion characteristic of their chars was also presented. The results indicated that the ignition temperature of hen manure char is about 70K lower than that of pig manure char. High heating rate and water steam atmosphere during char preparation both are beneficial to the combustion characteristic of the chars. The minerals contained can increase the combustion capability of the char greatly. There is little difference in the ignition and burnout temperatures of the chars prepared at different heating rates. With the increase of the final temperature, the combustion reactivity of pig manure char increases firstly and then decreases.