CAJ | 학술논문

连续热解是一种高效的生物质能转化技术，无轴螺旋式连续热解装置不仅可减轻送料部件的质量，而且为热解挥发性产物的排出提供了有效空间，是极具发展前景的连续热解装置。为了解无轴螺旋式生物质连续热解特性，该文在无轴螺旋连续热解装置上，开展了以稻壳、花生壳和木薯茎秆为生物质原料的热解试验，分析了3种生物质在不同热解温度下的三态产物分布特性、热解气体组分变化规律及热解炭的组织结构和表面形貌特征。结果表明：炭产率随热解温度升高逐渐下降，气体产率逐渐上升，液体产率先上升再下降，在450℃时达到最大，产物分布特性与其他热解反应器的一致；不同原料炭产率由高到低依次为：稻壳＞花生壳＞木薯茎秆，液体产率由高到低依次为：稻壳＞花生壳＞木薯茎秆，气体产率与液体产率相反。热解气体组分受温度影响较大，热解温度升高，可燃气体组分含量不断上升，不可燃气体组分含量不断下降，不同原料对气体组分含量影响较小。热解炭的工业分析结果与原料的工业分析结果存在相关性，热解温度升高，热解炭中挥发分含量逐渐下降，固定碳及灰分含量增加，木薯茎秆炭的挥发分含量最高，花生壳炭的固定碳含量最高，稻壳炭的灰分含量最高；低温热解炭的表面官能团较为丰富，随热解温度升高官能团种类逐渐减少；原料自身结构特性对热解炭的表面形貌影响较大，随着热解温度升高，生物质原料的表面结构不断被破坏，热解炭表面出现孔隙结构，花生壳炭与木薯茎秆炭表面孔隙结构比稻壳炭更为发达。
련속열해시일충고효적생물질능전화기술，무축라선식련속열해장치불부가감경송료부건적질량，이차위열해휘발성산물적배출제공료유효공간，시겁구발전전경적련속열해장치。위료해무축라선식생물질련속열해특성，해문재무축라선련속열해장치상，개전료이도각、화생각화목서경간위생물질원료적열해시험，분석료3충생물질재불동열해온도하적삼태산물분포특성、열해기체조분변화규률급열해탄적조직결구화표면형모특정。결과표명：탄산솔수열해온도승고축점하강，기체산솔축점상승，액체산솔선상승재하강，재450℃시체도최대，산물분포특성여기타열해반응기적일치；불동원료탄산솔유고도저의차위：도각＞화생각＞목서경간，액체산솔유고도저의차위：도각＞화생각＞목서경간，기체산솔여액체산솔상반。열해기체조분수온도영향교대，열해온도승고，가연기체조분함량불단상승，불가연기체조분함량불단하강，불동원료대기체조분함량영향교소。열해탄적공업분석결과여원료적공업분석결과존재상관성，열해온도승고，열해탄중휘발분함량축점하강，고정탄급회분함량증가，목서경간탄적휘발분함량최고，화생각탄적고정탄함량최고，도각탄적회분함량최고；저온열해탄적표면관능단교위봉부，수열해온도승고관능단충류축점감소；원료자신결구특성대열해탄적표면형모영향교대，수착열해온도승고，생물질원료적표면결구불단피파배，열해탄표면출현공극결구，화생각탄여목서경간탄표면공극결구비도각탄경위발체。
Technology of continuous pyrolysis is an effective method of disposing biomass, and the shaftless-screw-conveying pyrolysis reactor, which is a kind of device with great development prospects, can not only reduce the weight of the conveying mechanical components, but also provide effective space for the removal of volatile products. At present, there were few researches on the biomass continuous pyrolysis characteristics with the shaftless screw conveying reactor. So, the continuous pyrolysis of rice husk, peanut shell and cassava stalk was investigated on the shaftless-screw-conveying reactor, and the product distribution, the pyrolysis gas components and the pyrolytic charcoal characteristics of the 3 biomasses at different pyrolysis temperatures were analyzed. The pyrolysis characteristics were compared with the existing pyrolysis technology, and the material adaptability of the reactor was discussed. This paper provided a theoretical basis for the determination of the process parameters of biomass continuous pyrolysis and the utilization of pyrolysis products of different biomass materials. The results showed that the distribution of pyrolysis products was consistent with other pyrolysis reactors. With the increase of pyrolysis temperature, the charcoal yield decreased gradually, the gas yield increased, and the liquid yield increased firstly and then decreased, which reached the maximum at 450℃.The maximum liquid yield of rice husk, peanut shell and cassava stalk was 35.24%, 33.04% and 31.94% respectively. The gas yield and liquid yield presented a competitive relationship. For different bio-materials, the order of the charcoal yield from high to low was: rice husk > peanut shell > cassava stalk, the liquid yield from high to low was: rice husk > peanut shell > cassava stalk, and there were contrary rules between the gas yield and the liquid yield. The pyrolysis gas was mainly composed of CO2, CH4, H2, C2H4 and CO and the gas component content was influenced by temperature greatly. With the increase of reacting temperature, the content of the combustible gas rose, and non-combustible gas components declined. The relative content of combustible gas in pyrolysis gas reached 75% at reaction temperature 650℃. Different bio-materials had little effect on the composition and content of the gas. The industrial analysis results of the pyrolysis carbon were related to that of the raw materials. With the pyrolysis temperature increasing, the volatile content of the pyrolysis charcoal decreased gradually, and the ash and the fixed charcoal content increased. There were differences of the functional groups among different kinds of charcoals, the surface functional groups of peanut shell charcoal was more abundant than that of rice husk charcoal. In the 3 kinds of charcoals, the highest contents of volatile, ash and fixed carbon were obtained from cassava stalk charcoal, rice husk charcoal and peanut shell charcoal respectively. The structure characteristics of raw material had a greater influence on the surface morphology of carbon. The surface functional groups of low-temperature-pyrolysis charcoal were very rich, the type of the surface functional groups reduced gradually with the pyrolysis temperature increasing. The surface structure of biomass materials continued to be destroyed, and pore structure appeared when the pyrolysis temperature increased. The structure characteristics of raw material had a significant influence on the surface morphology of carbon, and the surface pore structure of peanut shell charcoal and cassava stalk charcoal was more than rice husk charcoal.