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In this experiment, with stainless steel gas cyclone-liquid jet absorption separator as carrier, NH as experimental gas, and water and HPO solution as absorbents, corresponding NH absorption rate change is obtained through the adjustment of experimental parameters, such as NH inlet concentration, inlet velocity of mixed gas, injection flow rate of absorbent, temperature of absorbent, and HPO absorbent concentration. The NH absorption rate decreases with the increase in NH inlet concentration and inlet gas velocity. The NH absorption rate will increase first and then tends to remain unchanged after reaching a certain degree with the increase in liquid injection flow rate and absorbent concentration. The NH absorption rate will increase first and then decrease with the increase in the absorbent temperature. The maximum NH removal efficiencies of water and HPO were 96% and 99%, respectively.

The large amount of waste gas containing volatile organic compounds (VOCs) discharged from petrochemical sewage plants will cause air pollution and seriously endanger the safety of human beings and the ecological environment. In this paper, we proposed a photocatalytic oxidation degradation technique of VOCs and designed a photocatalytic reaction device loaded with TiO 2 / SnO 2 catalyst. Under UV light irradiation, there is an energy level difference in the conduction band between TiO 2 and SnO 2 , which makes the photogenerated electrons (e − ) migrate to SnO 2 and reduces the surface electron density of TiO 2 . Thus, the recombination of photogenerated electron−hole pairs (e − −h + ) is inhibited and the catalyst activity is improved. Meanwhile, the synergistic effect of the oxidation of hydroxyl radicals (•OH) and ozone greatly improves the conversion rate. In addition, in the industrial side line, by studying the influence of inlet gas volume, inlet gas concentration, and gas humidity (RH) on the conversion rate of the VOCs, we revealed the operation law of the photocatalytic technique in industrial applications. Under the best working conditions, the purification rate of the VOCs was as high as 92.73%. This technique can not only effectively avoid the damage to the environment caused by polluting VOCs but also promote the low-carbon and green development of enterprises in the industry.

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Industrial flue gas systems include fine soot and high-temperature vapor. The continuous emission of the flue gas not only causes fine particulate pollution but also wastes considerable heat energy. Separating soot and purifying flue gas are of great significance for industrial conditions and environmental protection. In this paper, the process of cyclone soot elimination and waste heat recovery by heterogeneous condensation were coupled for the first time. The effects of the flue gas material system and separation operation parameters on the cyclone soot elimination efficiency and heat transfer efficiency were systematically investigated through unit experiments and industrial side-lines. Additionally, the mechanism of enhanced cyclone soot elimination by heterogeneous condensation was also theoretically explored. The experimental results show that the corresponding maximum cyclone heat transfer efficiency and soot elimination efficiency of the Ф40 mm cyclone separator are 42.1% and 89.2%, respectively, while the Ф80 mm cyclone separator can attain an elimination efficiency of 91% and a maximum increase of 67.3% for the heat transfer efficiency, as indicated by the industrial side-line. During the process of cyclone soot elimination and heat recovery by heterogeneous condensation, the heterogeneous condensation caused by heat transfer increases the quality difference between the flue gas molecules and soot droplets, thus improving the cyclone separation efficiency of soot.

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