防冻型抑尘剂的合成及性能研究

发布时间：2018-11-18 14:19

【摘要】：大气颗粒污染物对环境的影响和人类健康的影响日益突出,并逐渐引起世界各国的普遍关注。大气颗粒污染物是衡量城市空气质量的主要指标,而作为大气颗粒污染物重要组成部分的道路扬尘应该引起人们的关注,成为研究的主要对象。使用道路抑尘剂降低扬尘是一种有效的方法,迄今为止,所用的抑尘剂产品效果较差,且有可能造成二次污染。为了解决我国城市中,尤其是北方城市道路扬尘对空气质量的影响,需研制出一种针对性强,高效环保的抑尘剂,控制城市粉尘的传播与扩散。本论文研制的是一种防冻型沥青道路抑尘剂,主要应用于城市的沥青道路抑尘,通过对润湿型、粘结型、凝聚型抑尘剂的研究,综合了它们的优点和缺点,确定研制一种集吸水、保湿、凝并为一体且具有一定防冻功能的复合型抑尘剂。论文首先以单体实验为基础,在具有吸湿性、凝并性、润湿性和保水性的化学物质中各自选择三种,通过检测其失水率、粘度、表面张力等指标确定质量浓度15%-25%的CaCl2为吸湿剂,质量浓度0.05%-0.15%的聚丙烯酸钠为凝并剂,质量浓度0.005%-0.5%的十二烷基苯磺酸钠为本实验的表面活性剂,质量浓度0.4%-0.8%的丙三醇为保水剂。实验选择多因素多水平的正交实验,确定抑尘剂的最优配方,通过吸湿性、粘度、抗蒸发性、pH值等评价指标,分析各因素对各指标的影响,得出聚丙烯酸钠和CaCl2具有较好的吸湿性能,且聚丙烯酸钠的吸湿性能优于CaCl2,聚丙烯酸钠对粘度和pH值起最主要的影响,聚丙烯酸钠和丙三醇具有较好的保水性能,丙三醇在抑尘剂配方中主要起保水作用。得出抑尘剂所需的最佳浓度。最后对最优配方的pH值、粘度、吸湿放湿性、抗风蚀性、对沥青混合料强度的影响、毒性及冰点等性能进行测定,结果表明抑尘剂pH值呈中性,粘度值测量结果为36 mpa·s,能够抵御30m/s的风力侵蚀,风蚀率小于1%,道路抑尘剂有很好的抗风蚀效果。该抑尘剂经过十天的吸湿放湿性测试,尘样含湿量最大可以达到9.0%,最低含湿量仍然能够保持在4%以上,并且10天之后没有明显的递减趋势,由此可以得出尘样仍具有能够吸收空气中水分的性能,故本实验研制出的抑尘剂抑尘效果显著,并具有吸湿放湿的特性。通过实验可知道路抑尘剂对沥青道路强度的影响和自来水对沥青道路强度的影响差不多,硫化橡胶和碳钢(16Mn)在道路抑尘剂与蒸馏水中的耐蚀性对比试验,结果表明道路抑尘剂和蒸馏水对硫化橡胶和碳钢(16Mn)的腐蚀性差不多。由于条件限制,本文对抑尘剂的抑尘效果只做了小型的校园道路试验,结果表明该抑尘剂能够显著降低大气总悬浮颗粒物的含量且保湿时间长。
[Abstract]:The impact of particulate pollutants on the environment and human health has become increasingly prominent, and has gradually attracted the attention of countries all over the world. Atmospheric particulate pollutant is the main index to measure urban air quality, and road dust, which is an important part of atmospheric particulate pollutant, should be paid attention to and become the main object of study. It is an effective method to use road dust suppressant to reduce dust raising. Up to now, the effect of the dust suppressant used is poor, and it may cause secondary pollution. In order to solve the influence of road dust on air quality in Chinese cities, especially in northern cities, it is necessary to develop a dust suppressant with strong pertinence, high efficiency and environmental protection to control the spread and diffusion of urban dust. In this paper, a kind of antifreeze asphalt road dust suppressant is developed, which is mainly used in urban asphalt road dust suppression. Through the research on wetting type, adhesive type and condensed type dust suppressant, it synthesizes their advantages and disadvantages. A kind of compound dust suppressant, which can absorb water, moisturize and coagulate, and has certain antifreeze function, is developed. First of all, based on the monomer experiment, three kinds of chemical substances were selected in this paper, which have the properties of moisture absorption, coagulation, wettability and water retention, and their water loss rate and viscosity were measured. Surface tension and other indicators determined that the mass concentration of 15% to 25% of CaCl2 was a moisture absorbent, and the mass concentration of 0.05% sodium polyacrylate was used as a condensation agent. Sodium dodecylbenzenesulfonate (0.005%) was used as surfactant and glycerol (0.4% -0.8%) as water-retaining agent. The optimum formula of dust suppressant was determined by orthogonal experiment with multi-factor and multi-level. The influence of each factor on each index was analyzed by evaluating indexes such as moisture absorption, viscosity, evaporation resistance, pH value, etc. The results showed that sodium polyacrylate and CaCl2 had better hygroscopicity, and the hygroscopicity of sodium polyacrylate was better than that of CaCl2,. Sodium polyacrylate and propanediol had better water retention. Propanetriol plays an important role in keeping water in the formulation of dust suppressant. The optimum concentration of dust suppressant was obtained. Finally, the pH value, viscosity, hygroscopicity, wind erosion resistance, the effect on the strength, toxicity and freezing point of asphalt mixture were determined. The results showed that the pH value of dust suppressant was neutral, and the viscosity value was 36 mpa s. It can resist the wind erosion of 30m/s, and the wind erosion rate is less than 1. The road dust suppressant has a good anti-wind erosion effect. After ten days of moisture absorption and hygroscopicity test, the maximum moisture content of dust sample can reach 9.0, the minimum moisture content can still remain above 4%, and there is no obvious decreasing trend after 10 days. It can be concluded that the dust sample still has the ability to absorb moisture in the air, so the dust suppressant developed in this experiment has a remarkable dedusting effect and has the characteristics of moisture absorption and moisture release. The influence of road dust suppressant on asphalt road strength is similar to that of tap water on asphalt road strength. The corrosion resistance of vulcanized rubber and carbon steel (16Mn) in road dust suppressant and distilled water is compared. The results show that road dust suppressant and distilled water have similar corrosivity to vulcanized rubber and carbon steel (16Mn). Due to the limitation of the conditions, the dust suppression effect of the dust suppressant is only tested on a small campus road. The results show that the dust suppressant can significantly reduce the content of the total suspended particulates in the atmosphere and retain the moisture for a long time.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X513

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