Project Synopsis

Determine operating limits and scrubber capacities of existing units as well as determine future modifications for maximizing scrubber performance.

Project Summary


Process Engineering Associates, LLC (PROCESS) was subcontracted by an engineering firm to execute an operational evaluation two acid gas scrubbers located at a batch specialty chemical production facility in the U.S.  Specifically, PROCESS was charged with determining the operating limits of the scrubbers as pertains to total flow and acid scrubbing capacities as well as determining future process modifications and operating conditions for maximizing the scrubbers’ performances.  PROCESS modeled the scrubbers for two separate facility offgas streams, one containing hydrogen chloride (HCl) and the other containing sulfur dioxide (SO2).

PROCESS performed the following tasks:

  • Performance of an initial site visit and interviewing of engineering, environmental, and operations personnel for the purpose of collecting engineering and operations data for the scrubber systems and vent gas streams
  • Development of a process and regulatory evaluation basis that set forth the vent streams physical and chemical characterizations and scrubber systems performance requirements
  • Development of initial computer process simulation models of the scrubber systems using licensed commercial process simulation software for determining scrubber systems current operation
  • Development of additional computer process simulation models to determine the maximum achievable performance of the scrubber systems for the vent streams of interest and for ascertaining the operating conditions needed to achieve said performance
  • Preparation of a process evaluation report presenting PROCESS’ project findings, including recommendations for improving the operation of the scrubbers

Limiting factors for the HCl vent stream included heats of absorption and reaction, while the limiting factor for the SO2 stream was the facility permit limit for SO2 emissions.  For maximizing systems capacity and performance, PROCESS recommended increases in the pH setpoint values to enhance operating stability, different packing to increase hydraulic capacity, and additional heat removal capabilities to increase the HCl stream throughput limit. 

Industry Type

  • Batch Specialty Chemical

Utilized Skills

  • Collect operational data
  • Identify regulatory operational limits
  • Computer process simulation
  • Report recommendations