Existing Conditions
The RTO system, installed in 2014, exhibited severe corrosion, accumulation of acidic condensate at the base, and increased HCl emissions through the stack after several years of operation – all of which indicated a systemic process issue.
When upstream treatment isn’t feasible – we treat wisely downstream.
A creative engineering solution that prevented emissions, reduced maintenance, and protected facility infrastructure.
Vladislav Kositsky | Head of Service and Maintenance Department
Solution
A.B.P. Chemical Engineering and Ventilation Ltd. performed an in-depth process analysis to trace the emission source.
The assessment included characterization of all vent lines from each production unit, preparation of a detailed gas sampling plan, and data analysis to locate the origin of the chloride emissions.
The investigation revealed that some local scrubbers were not operating efficiently and required adjustment. More importantly, significant emissions of organic gases containing chlorine atoms were detected – compounds that could not be effectively absorbed in local scrubbers.
Since this issue could not be resolved upstream, A.B.P. Chemical Engineering and Ventilation Ltd. developed a downstream treatment solution for the RTO exhaust stream, integrating a quencher and an alkaline scrubber system.
To further mitigate corrosion damage, a pre-heating stage was introduced at the RTO inlet, raising the dew point of water and HCl to reduce acidic condensation within the system.
Phase One – Quencher
The exhaust gases exiting the RTO are hot and must be cooled before treatment to protect downstream system materials.
A.B.P. Chemical Engineering and Ventilation Ltd. designed a two-stage quencher column that sprays recirculated water over the incoming gas stream, reducing its temperature through controlled evaporation.
Phase Two – Absorption Column
To treat residual HCl vapors and chlorine gas (Cl₂) emitted from the RTO, A.B.P. Chemical Engineering and Ventilation Ltd. designed a packed alkaline absorption column.
The system facilitates mass transfer of contaminants from the gas phase to the liquid phase, neutralizing them into environmentally safe compounds.
The treated gases are then released to the atmosphere through a stack positioned atop the absorber column.
Results
After installation and full commissioning of the quencher and scrubber systems, stack testing confirmed full compliance with Ministry of Environmental Protection requirements.
Corrosion damage within the RTO system was substantially reduced thanks to thermal improvements at the gas inlet and lower acidic condensation levels.
