摘要
该文旨在确定渗灌渗水涂层成分的配比方案,制备出渗水性能良好的渗灌滴头。通过对所选用的蒙脱土MMT及聚丙烯酰胺PAM材料的结构和性能进行了分析和比较,设计制备工艺,制备渗灌滴头,在实验室内搭建了渗灌材料的实际渗水的试验平台;采用拉伸强度试验对渗灌导水涂层材料与纤维结合性能进行研究,用电子显微镜对不同配比的渗灌导水材料的形貌进行了观察并对其微观结构和组成进行了分析,在不同环境条件下对渗灌材料的渗水自调节性进行分析。结果表明:PAM/MMT悬浮液的配比为0.20 g/50 m L(1∶250)时导水材料的成膜性较,涂层成膜性较好,分布较均匀。对于以1∶250聚丙烯酰胺和蒙脱石制备的的渗水材料,温度一定时,随着环境土壤含水率的逐渐增加,渗水速率逐渐降低,土壤含水率一定时,随着环境温度的增加,渗水速率逐渐下降。该研究为渗灌材料制备提供参考。
Infiltrating irrigation is a kind of effective water-saving irrigation technology because it has many technical advantages including extensive application in agriculture, especially for tree irrigation in arid and semiarid regions. This study aimed to design a kind of infiltrating irrigation material that could realize self-adjusting and non-pressure water-supply under different environmental conditions as well as ensure normal plant growth with better property of saving water and energy. Through theoretical analysis and based on experience, montmorillonite（MMT） and polyacrylamide（PAM） were used to form infiltrating irrigation water-conductivity material. Different mass ratios of MMT and PAM were designed including proportions of PAM and MMT suspension of 1：1000（0.05 g/50 mL）, 1：500（0.1 g/50 mL）, 1：333（0.15 g/50 mL）, 1：250（0.2 g/50 mL）, 1：200（0.25 g/50 mL）, and 1：167（0.3 g/50 mL）. The fiber was used as the supporting material that was pre-treated. The fiber was immersed into the composite colloidal solution for 10-15 min, followed by infiltration and drying at 15-20 min in a DHG- 9023 A electron-thermal constant temperature blowing dry box（85℃）. Then, the coated fiber with function of water-conductivity was to make infiltrating irrigation droppers in an injection molding machine. Meanwhile, water-transmitting fibers（the fiber bundle, about 15 cm in length, about 5 mm in radius） coated with composite of different components were used for tensile test to determine he bonding properties of infiltrating irrigation water-conducting coating materials on fiber. Coating morphology was observed under a scanning electron microscope（SEM）. In addition, the micro-structure and composition were analyzed. The water permeability property of the droppers was tested under soil moisture content of 3%, 6%, 12%, and 18% at 20℃ and 20, 35, 50, 65℃ with soil moisture 3%. Results showed that coating materials with different PAM and MMT ratios all had breaking strength larger than 250 MPa, meeting the requirements for strength between coating material and fiber（200 MPa）. Microscope analysis showed that among different PAM and MMT ratios, the ratio of 1：250 could lead to best film-forming property such as uniform granule distribution. At 30 min, the maximum water penetration rates of sample with different PAM and MMT ratios from 1：1000 to 1：167 were 2.7, 2.5, 3.4, 2, 1.8, and 1.6 mm/min. For the film made of the PAM and MMT ratio of 1：250, the water penetration rates decreased gradually with soil moisture（3%, 6%, 12%, 18%） at 20℃, while it increased with temperature for soil with moisture of 3%. Therefore, the PAM and MMT ratio 1：250 could be used to develop materials for infiltration irrigation.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2014年第24期74-81,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金资助项目(50772131)
教育部科学技术研究重点项目资助项目(106086)
中国矿业大学(北京)中央高校基本科研业务费专项资金资助项目(2010YJ05)
关键词
灌溉
材料
土壤
渗灌材料
自调节
无压渗水
irrigation
materials
soils
infiltrating irrigation material
self-adjusting
non-pressure water-supply
