The hot air generated from the first layer of the converter and SO3 second cooler can be used for silica gel regeneration, extra hot air produces steam and hot water for raw material and finish product heat tracing. Then partial remaining hot air (100℃) further goes to Unit 38 to treat the wastewater coming from the scrubber. Crystal Na2SO4 hydrate will be produced by oxidizing the NaSO3 and Na2SO4, and evaporating water in the wastewater. Therefore, the plant can realize ZERO wastewater discharge from scrubber. 

The main reaction heats from the sulfur furnace and the converter generate steam directly by using a fire-tube boiler.   Compared with the traditional technology, this process generates twice steam. Apart from being used in the sulfur melting unit, the steam can fully fulfill the requirement of chilling in air drying unit by replacing the electric driven chiller with steam driven lithium bromide chiller for generating chilling water. The power consumption can be 15% lower. 

Patented revolutionary technology. It circulates the system exhaust gas from the ESP outlet to the main process air, raises gas pressure and adds oxygen, then goes through the process of sulfur burning and conversion, sulfonation, and exhaust gas treatment. It manages to reuse the exhaust gas discharged from the ESP, and reduces the exhaust gas discharged to the atmosphere by 96% (meaning only 4% actual emission compared with the traditional process). Meanwhile, this process reduces the caustic soda unit consumption by 7kg on 100% basis, and 2-3kg sulfur.

In recent years, Weixian has maintained a strong focus on ultra-low dioxane technology. Building on the previous Unit 79 Neutralization and Dioxane Stripping process, Weixian has newly developed the Unit 89 Dioxane Multi-stage Stripping process, which achieves a dioxane removal rate of 65% to 99%, depending on specific needs. With this innovative technology, a dioxane content of less than 1 ppm can be reliably achieved, regardless of the raw material’s EO number or initial dioxane level.   In April 2026, Weixian engineers have successfully commissioned an ultra-low dioxane system in South Korea.    Through meticulous optimization of operating parameters, the system achieved an impressive 88.7% removal efficiency, reducing dioxane concentration from 9.88 ppm to 1.13 ppm. The client is highly satisfied with the results, and further reduction in dioxane levels is achievable upon request.   This breakthrough allows any sulphation plant to comply with the strictest SLES dioxane limits demanded by high-end markets, while keeping costs relatively low.