地膜为农业发展带来了极大的便利,但由于其稳定的理化性质,在自然条件下极难进行处理,若处理不当极易对环境造成严重威胁.为了探究低温等离子体降解技术中不同实验因素对农业地膜降解效果的影响,本研究采用自制针板电极结构,通过施加高频交流电压对聚乙烯地膜进行了等离子体处理.分析了输入功率、放电时间、电极数量以及空气流通等因素对地膜降解率的影响.通过地膜质量、拉曼光谱图、扫描电子显微镜以及相对分子质量等参数对比了处理前后地膜的变化.结果表明:当输入功率由 26 W 上升至 80 W,地膜降解率提升了约 2.6倍,提高输入功率可以增加反应空间内的高能电子和活性物质,但能量效率并未随降解率而升高,当输入功率为 51 W 时,能量效率最高为 58.82 μg/(W·h);针尖数量会影响等离子体的均匀性和输入功率,随着针电极数量增加,地膜降解率由 3.49％下降至 2.1％后又上升到 3.57％;延长放电时间会导致分子链结构更容易受到等离子体攻击,发生断裂;此外,空气流动性会影响反应器内的臭氧浓度,当输入功率较低时,密闭环境下臭氧浓度更高,当输入功率提升至 80 W,具有良好空气流动性情况下臭氧浓度更高,有助于提升地膜降解率.
Effects of needle-plate corona plasma on improving the degradation of agricultural mulch film
Mulch film has provided significant convenience for agricultural development.However,its stable physical and chemical properties make it challenging to manage under natural conditions,potentially posing a serious environmental threat if mishandled.This study investigates the influence of various experimental factors on the degradation of agricultural film using low-temperature plasma degradation technology.A self-made needle-plate electrode structure was employed to treat polyethylene film with a high-frequency AC voltage.The study analyzesd the effects of input power,discharge time,electrode number,and air circulation on mulch film degradation.Changes in mulch quality,Raman spectrum,scanning electron microscope observations,and relative molecular mass were compared before and after treatment.The results revealed a 2.6-fold increase in mulch film degradation efficiency when the input power rised from 26 W to 80 W.While increasing input power enhanced high-energy electrons and active substances in the reaction space,energy efficiency did not proportionally increase with the degradation rate.At 51 W input power,the energy efficiency reached a maximum of 58.82 μg/(W·h).The number of needle tips influences plasma uniformity and input power,impacting film degradation efficiency.As the number of needle electrodes increases,film degradation efficiency initially decreased from 3.49％to 2.1％,then rised to 3.57％.Prolonged discharge time made the molecular chain structure more vulnerable to plasma attack and breakage.Additionally,air fluidity affects ozone concentration in the reactor,with higher concentrations in a closed environment at low input power.Increasing the input power to 80 W results in higher ozone concentration with good air fluidity,aiding in improving mulch film degradation efficiency.
Needle plate electrodePolyethylene filmHigh frequency ACPlasma
万方数据
维普
