Can the thick white smoke from a chemical plant be eliminated?

Let me share a case: The desulfurization, denitrification, and dust removal unit of the light catalytic cracking unit at Sinopec Guangzhou Petrochemical uses wet scrubbing to remove unwanted components from flue gas. However, when the water used for scrubbing the flue gas turns into steam and is released, it results in the formation of \"white smoke,\" with water vapor being the main component of this \"white smoke.\" This thick white smoke leads nearby residents to speculate that the petrochemical plant is emitting pollutants once again. Although the company uses various channels and media to explain the principles of desulfurization and denitrification and to clarify that the white smoke is actually water vapor, this does not fully dispel the misunderstandings.

Guangzhou Petrochemical has set deep dust and mist removal as well as smoke whitening as its key objectives. It employed the deep dust and mist removal and smoke whitening technology jointly developed by Ningbo Engineering Company and Dalian Petrochemical Research Institute to upgrade the desulfurization scrubber tower, adding a water washing section to further enhance the desulfurization and denitrification effects. It also provided an inlet and pipelines for heated air to enter the chimney. .

After the device resumed operation, it achieved the desired whitening effect. The white clouds have disappeared; the vast expanse of blue sky is truly breathtaking!

Deep dust and mist removal, as well as white smoke elimination technologies, offer the advantages of low pressure, small space requirements, high pollutant removal efficiency, and a long operational lifespan. The overall technology has reached the international leading level. This technology has developed an efficient dust and mist removal as well as flue gas reheating process based on phase change condensation; it has also invented a phase change swirl condensation washer. Using sub-micron particles as nucleation sites and circulating water as a cooling medium, this system creates tiny droplets through condensation phase changes. The centrifugal force and flow redirection mechanisms are then used to combine these small droplets into larger ones, during which gaseous pollutants are dissolved into the droplets. This approach eliminates white smoke and salt rain, enabling efficient simultaneous purification of pollutants such as SO2, catalyst dust, NH3, and soluble salts.

If the emissions meet the standards, the cost of eliminating water vapor alone is indeed very high.

White smoke is easy to control, but water vapor is hard to remove. Especially in the northern regions during cold seasons, a large amount of water vapor escapes from the higher-temperature channels along with the exhaust gases, and this cannot be eliminated; it is also a sign of the thriving development of industrial enterprises: lol:lol:lol

Complete whitening is definitely achievable technically; so how is the contradiction between investment costs and the necessity of such a solution addressed in practice? If every pollutant is actually discharged up to the required standards, what is the point of eliminating whitening effects? Is environmental protection today merely about addressing the consequences of previous problems?

It can be eliminated by adding a cooler – essentially a large heat exchanger – to lower the temperature of the flue gas; the lower the flue gas temperature, the better the effect. Now, from 200 meters away, it’s impossible to tell clearly if there is white smoke or not; there’s only a faint hint of it. The amount of water used for cooling is very large.