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	秸秆坯块成型工艺参数及保水性试验研究
其他题名	Optimization of forming process parameters and water retention performance of straw blocks
	宫元娟; 邓楠; 刘德军; 白雪卫; 邱硕
来源期刊	农业工程学报
ISSN	1002-6819
出版年	2019
卷号	35 期号:12 页码:248-255
中文摘要	为探究玉米秸秆、豆粕和聚丙烯酸钠混合制备农用保水剂的生产工艺,以最大压缩力、混料水分、压缩速度、豆粕质量分数和聚丙烯酸钠质量分数为试验因素,以成型坯块的松弛密度为评价指标进行二次回归旋转组合试验,优化工艺参数组合并试验验证,在松弛密度的最优范围内分析其对坯块保水性能的影响。试验结果表明:坯块的松弛密度为460~540 kg/m~3的条件下,得出最大压缩力为16~20.59 kN,混料水分为8.84%~12.96%,压缩速度为95.56~ 155.51 mm/min,豆粕质量分数为16.08%~24.02%,聚丙烯酸钠质量分数为4.91%~7.15%的最佳成型工艺参数;坯块的保水效果随松弛密度的增大而逐渐增强,有砂土时释水量随时间变化符合对数模型,无砂土时则符合线性模型,拟合方程的回归系数均大于0.9,成型坯块保水性的分析可靠,可为复合型农用保水剂的应用提供参考。
英文摘要	The preparation of straw-based agricultural water-retaining agent is one of the effective ways to utilize crop resources. It can solve the problems of low soil nutrient content and low utilization rate of cultivated land in arid and semi-arid areas of Northwest Liaoning. However, the characteristics of straw such as dispersed texture, low bulk density, high cost in storage and transportation restrict its large-scale and value-added utilization. As a result, the biomass densification technique has attracted wide attention. To the best of our knowledge, the physical properties of the densified products are influenced by the mixing conditions of raw materials, pressing parameters and types of binders, and addition of high protein yellow soybean meal powder into soil can improve the quality of crops, ripen the soil, kill or inhibit soil harmful bacteria, and achieve the balance of fertilizer supply, while the white sodium polyacrylate as the binder can improve the stability and absorption of the products. Therefore, these two components were mixed with straw blocks proportionally to make samples with different water content in this study, then the mixture was loaded into a compression die (50 mm inner diameter and 80 mm height) that controlled by the WDW-200 electronic universal testing machine. The clamp of the testing machine held the die head and keeps the plumb state. After maximum compression force and compression speed were set by a computer, the machine started to move downward, and densified block was extruded from the die at a room temperature. The quality, diameter and height of the product were measured after a complete relaxation, and the relaxation density was calculated. To explore an optimal forming process of agricultural water-retaining agent, a quadratic general rotary combination design was adopted, with the maximum compression force, moisture content of mixture, compression speed, mass fraction of soybean meal and mass fraction of sodium polyacrylate were test factors. The softwares of Design-Expert 8.0.6 and Excel 2010 were applied for the variance analysis and response surface analysis of experimental results, with the aim to establish mathematical model between the index and each influencing factor, as well as optimize the combination of forming parameters. Furthermore, in the optimum range of relaxation density, the soil condition and climate conditions in Northwest Liaoning were simulated. The water retention capacity of formed blocks with or without the sandy soil medium were evaluated and compared by water release at intervals in a temperature controlled drying oven, and effect of relaxation density was analyzed as well. Results showed that the relaxation density was significantly affected by following four factors (P < 0.000 1), and the degree of importance were maximum compressive force > moisture content of mixture > mass fraction of sodium polyacrylate > mass fraction of soybean meal. Under the condition of relaxation density of 460-540 kg/m~3, the optimized combinations of cold forming parameters were maximum compression force of 16-20.59 kN, moisture content of mixture of 8.84%-12.96%, compression speed of 95.56-155.51 mm/min, mass fraction of soybean meal of 16.08%-24.02%, mass fraction of sodium polyacrylate of 4.91%-7.15%. The error was 1.03% in the test verification, which was reliable in prediction. The water-holding capacity of formed block was closely related to relaxation density, the water release increased with drying time, but decreased with the increase of relaxation density at the same temperature. Because the block with larger relaxation density had greater binding force on water, the water retention performance was better.
中文关键词	秸秆 ; 优化 ; 模型 ; 坯块 ; 成型工艺 ; 松弛密度 ; 保水性
英文关键词	straw optimization model block forming process relaxation density water retention performance
语种	中文
国家	中国
收录类别	CSCD
WOS类目	AGRICULTURAL ENGINEERING
WOS研究方向	Agriculture
CSCD记录号	CSCD:6550189
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/239348
作者单位	沈阳农业大学工程学院, 沈阳, 辽宁 110161, 中国
推荐引用方式 GB/T 7714	宫元娟,邓楠,刘德军,等. 秸秆坯块成型工艺参数及保水性试验研究[J],2019,35(12):248-255.
APA	宫元娟,邓楠,刘德军,白雪卫,&邱硕.(2019).秸秆坯块成型工艺参数及保水性试验研究.农业工程学报,35(12),248-255.
MLA	宫元娟,et al."秸秆坯块成型工艺参数及保水性试验研究".农业工程学报 35.12(2019):248-255.