沥青尾气净化塔及装置Asphalt exhaust gas purification tower and system
沥青烟气具有以下特点：沥青烟气组分极为复杂，既有沥青挥发组分凝结成的固体和液体微粒，又有蒸气状态的有机物，部分有机物是高分子聚合物,对环境造成严重污染。烟气中含有多种有机物，包括碳环烃、环烃衍生物及其它化合物，有不少对人身健康有危害作用，沥青烟含有苯并芘、苯并蒽、咔唑等多种多环芳烃类物质，且大多是致癌和强致癌物质，粒径多在0．1～1．0μm之间，最小的仅0．01μm，最大的约为10．0μm，尤其是以3，4-苯并芘为代表的多种致癌物质。其危害人体健康的主要途径是附着在8 um以下的飘尘上，通过呼吸道被吸人体内。吸入沥青烟能引起头痛、眩晕、恶心、呕吐、肝脏肿大和白血球增高等症状。接触沥青烟，可引起急性光敏性皮炎、角膜炎，并使皮肤产生明显的色素沉着，形成黑头粉刺、毛囊炎和血管肿瘤等。苯并(a)蓖等化合物还是致癌物质。
此外易粘附, 在一定温度之上易燃爆。在沥青烟气的收集、输送及消烟过程中, 极易粘着管道及设备表面形成液态至固态沥青。固结后的沥青很难清除掉, 往往造成管道堵塞、设备破坏, 使系统无法正常运行。
因此，对沥青烟气进行合理有效净化治理，使排放满足大气环境标准，又能保证装置正常生产运行是非常必要的。针对沥青烟气的特点，采用洗油吸收的方法和高效净化工艺，来处理沥青烟气，改善环境，使得净化后烟气满足《大气污染物综合排放标准》。工艺选择的主要设计原则为：
1） 采用先进、成熟、可靠的净化工艺和成套技术，净化效率高、设备选材合理、装置能够长周期稳定运行。
2） 吸收剂的来源可靠。
3） 净化系统运行成本低。
4） 副产品的处置途径可靠。
5） 保证尾气净化系统的状况不影响主体系统的正常运行。
The characteristics of asphalt fumes are as follows: The composition of asphalt fumes is extremely complex. There are both solid and liquid particles formed by the volatilization of asphalt components, as well as organic substances in vapor state. Some of these organic substances are high-molecular polymers, causing severe pollution to the environment. The fumes contain various organic compounds, including cycloalkanes, cycloalkane derivatives, and other compounds. Many of them are harmful to human health. Asphalt fumes contain various polycyclic aromatic hydrocarbons such as benzo[a]pyrene, benzo[a]anthracene, and carbazole, and most of them are carcinogenic and highly carcinogenic substances. The particle size is mostly between 0.1 and 1.0 μm, with the smallest being 0.01 μm and the largest being approximately 10.0 μm. Especially, various carcinogenic substances represented by 3,4-benzopyrene are included. The main way for it to harm human health is to adhere to the dust particles of 8 μm or less and be absorbed into the body through the respiratory tract. Inhalation of asphalt fumes can cause symptoms such as headache, dizziness, nausea, vomiting, liver enlargement, and increased white blood cells. Contact with asphalt fumes can cause acute photosensitive dermatitis, keratitis, and significant pigmentation on the skin, resulting in blackheads, folliculitis, and vascular tumors. Compounds such as benzo(a)pyrene are also carcinogenic substances.
In addition, it is prone to adhesion and is flammable and explosive at certain temperatures. During the collection, transportation, and smoke elimination process of asphalt fumes, it is easy to adhere to the surfaces of pipelines and equipment, forming liquid to solid asphalt. The consolidated asphalt is difficult to remove and often causes pipeline blockage and equipment damage, making the system unable to operate normally.
Therefore, it is very necessary to conduct reasonable and effective purification treatment of asphalt fumes to ensure that the emissions meet the atmospheric environmental standards and also guarantee the normal operation of the equipment. In view of the characteristics of asphalt fumes, the methods of oil absorption and efficient purification processes are adopted to treat asphalt fumes, improve the environment, and make the purified fumes meet the "Integrated Emission Standards for Air Pollutants". The main design principles for the process selection are:
1) Adopt advanced, mature, and reliable purification processes and complete technologies, with high purification efficiency, reasonable equipment selection, and the device being able to operate stably for a long period.
2) The source of the absorbent is reliable.
3) The operation cost of the purification system is low.
4) The disposal route of the by-products is reliable.
5) Ensure that the condition of the tail gas purification system does not affect the normal operation of the main system.
