以北京市大兴某生物质固体成型燃料厂为例,研究了不同季节供应的玉米秸秆、花生壳、木屑3种生物质原料物理和热化学特性的变化规律.结果表明,木屑的全水分质量分数较高,超过40％,花生壳和玉米秸秆为10％左右,不同种类原料的堆积密度、流动特性、发热量、灰分、挥发分等特性有一定差异.木屑的堆积密度较大,挥发分含量较高,灰分含量较低.木屑和花生壳的干燥基发热量较玉米秸秆高,但由于木屑的水分过高导致其收到基发热量较低.不同季节的同类原料理化特性也有差异,特别是水分、发热量、灰分差异显著.全水分含量随当地气候条件而变化,6月份之后,玉米秸秆、花生壳和木屑的干燥基发热量分别降低约7％、3.5％和5％.因此,在生物质原料储藏、运输、压缩成型等设备的设计过程中,应充分考虑不同种类原料堆积密度、流动特性等物理特性的差异,而生物质原料的燃烧过程,不仅涉及不同种类原料的差异,还应考虑不同季节造成的影响.%Change regularity of physicochemical properties of corn straw, peanut shell and sawdust which are supplied from different seasons was studied based on a case study of biomass solid fuel plant in Daxing district of Beijing. The results showed that total moisture of sawdust was higher, more than 40% . Total moisture of corn straw and peanut shell was about 10% . The bulk density, flow characteristics, calorific value, ash, volatile matter of three types of raw materials were varies. Sawdust had relatively high bulk density and volatile matter but lower ash. Peanut shell and sawdust dry basis calorific value was higher than corn straw high. However, as received basis calorific value has lower. Physicochemical properties of the same materials of different season were different; especially total moisture varied with the local climatic conditions. After June, dry basis calorific value of corn straw, peanut shell and sawdust were reduced about 7% , 3. 5% and 5% . Therefore, difference of physicochemical properties of several of raw materials such as bulk density, flow characteristics should be fully considered during related equipments design process of storage, transport, and compression forming of raw materials. Furthermore for the combustible characteristics of raw materials, not only difference of physicochemical properties should be considered, but also different seasons.
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