基于林业废弃物的秸秆生态板制备工艺研究

Study on the Preparation Technology of Straw Ecological Board from Forestry Waste

森林资源的匮乏和产品游离甲醛的超标问题是目前困扰我国人造板业发展的瓶颈。我国人造板生产和消费量大,由于从2016年起国家严格限制木材的采伐,刨花板生产原料来源受到了极大的限制,因此基于来源丰富和可再生的农林废弃物的环保生态板的制备就成为解决目前人造板产业发展的关键措施,本论文以果壳废弃物为原料,自制的木质素改性聚氨酯预聚物为胶粘剂,经热压工艺生产出符合使用要求的无甲醛中密度生态板。详细研究了果壳粉含水量、细度、粘合剂用量、热压温度、热压时间等参数对所制备板的综合性能的影响规律;确定了最佳的工艺条件为:果壳粉含水量10%、原料细度20~40目:80~100目(1:1)、粘合剂用量为原料质量的5.0%、热压温度140℃、热压时间20min,压力25.0MPa,在此条件下制备的板的各项性能指标均优于中密度板刨花板国家标准(GB/T 11718-2009)规定值。本研究结果为丰富的果壳废弃资源的有效利用提供了实际可行的途径。

Shortage of woody raw material and excess free formaldehyde in the product are the major obstacles in the development of plywood industry.China’s plywood production and consumption is huge,from 2016,China has carried out strict forest conservation policy,the plywood industry mostly relying on lumber encountered severe shortage of production material,therefore,using abundant and renewable forestry and agricultural by-products as the raw materials to product becomes the essential measure to solve the problem.this paper reports the formaldehyde-free high-quality plant fiber board preparation with nut shell powder,self-made lignin modified PU adhesive as the materials by thermal pressing process.The effect of moisture content of nut shell powder,its size,adhesive dosage,thermal temperature and time on the complex properties of the board were investigated in details.The optimized parameters are as follows:10%water content,its size of 20~40 mesh:80~100 mesh(1:1),the adhesive dosage of 5.0%,thermal pressing temperature 140℃,pressing time 20 min,pressure 25.0 MPa,the comprehensive properties is superior to the standards of GB/T11718-2009,without free-formaldehyde detected in the product.And this provided a practical way for the efficient utilization of abundant waste nut shell resource.