沥青抑烟剂研究现状浅谈

Discussion on the Current Research Status of Asphalt Fume Suppressants

针对沥青烟气排放问题,国内外学者对沥青抑烟剂进行了诸多研究。根据性质特点和作用机理,可以将现有抑烟剂分为阻燃剂、吸附剂、聚合物改性剂和新型抑烟剂,其代表物质分别为金属氢氧化物、膨胀石墨、SBS和电气石。阻燃剂能在短时间内脱水吸热,降低沥青温度以减少组分分解,同时隔绝氧气以抑制轻质组分挥发。吸附剂比表面积较大,烟气吸附效率高,吸附作用包括物理吸附和化学吸附。聚合物改性剂通过物理交联、化学交联和网格束缚作用固定沥青烟气。新型抑烟剂通常依靠其特殊结构或性能发挥作用,例如纳米硅酸盐的层状结构和电气石的热电性能。某种抑烟剂的作用机理并不是单一的,而是多种因素协同作用。抑烟剂的应用可能会对沥青路用性能产生不利影响,但是通过降低烟气排放可以延缓沥青流变性能的衰减。

To suppress asphalt fume emissions,scholars at home and abroad have carried out many studies on asphalt fume suppressants.According to the characteristics and mechanism of action,the existing fume suppressants can be divided into flame retardants,adsorbents,polymer modifiers and novel fume suppressants,and their representative substances are metal hydroxide,expanded graphite,SBS and tourmaline respectively.The flame retardant can dehydrate and absorb heat in a short time,reducing the temperature of asphalt and inhibiting the decomposition of components.At the same time,oxygen is isolated to discourage the volatilization of light components.The adsorbent has large specific surface area,so its fume adsorption efficiency is high.And the adsorption includes physical adsorption and chemical adsorption.The polymer modifier fixes the asphalt fume through physical crosslinking,chemical crosslinking and grid binding.Novel fume suppressants usually produce a marked effect through their special structures or properties,such as the layered structure of nano silicate and the thermoelectric properties of tourmaline.The mechanism of action of a certain smoke suppressant is not singular,but rather a synergistic effect of multiple factors.The application of fume suppressants may have adverse effects on asphalt pavement performance,but the attenuation of asphalt rheological properties can be delayed by reducing fume emissions.