Perform a process engineering study of the steam generation systems at a chemical production facility.
STEAM BOILER SYSTEMS IMPROVEMENT STUDY
The client is a global specialty chemicals manufacturer who contracted Process Engineering Associates, LLC (PROCESS) to perform an improvement study of the steam system at one of their chemical process plants in the U.S. The study had two principal objectives: (1) to evaluate the design and performance of the steam generation system and propose improvements to increase its operational reliability and energy efficiency, and (2) to develop a plan to increase steam production from one of the boilers so that the other one could be taken out of service.
The steam generation system consists of two gas fired fire-tube package boilers: a 700 HP Hurst (primary), and a 300 HP Cleaver Brooks (secondary) that supply steam to polyester acrylates and urethanes batch plants by means of a common header. The Hurst boiler also serves as the environmental control device for the polyester acrylates plant-process vent gases containing ~0.1% VOC’s (in the combustion air supply). Consequently, a shutdown of this boiler will halt production at the site. Condensate is returned to the boilers, and excess steam is condensed when steam demand is low.
The client had identified specific operational issues that (1) directly impacted the reliability and energy efficiency of the Hurst boiler, and (2) disrupted and/or had previously shut down production. These included failure of the feedwater pumps, boiler level control issues, backup of condensate in the excess steam condenser, a low (65-70%) operating efficiency, and the inability to achieve its maximum design steam rate.
The project deliverables were presented to the client in a comprehensive report that included:
- The process study basis
- A comprehensive review of the design and operation of the steam generating system
- A mass and energy balance around the Hurst boiler for the existing operating conditions
- A model for the vent system to evaluate the planned higher vent gas flowrates and vent system rebalancing in support of the higher boiler firing rate
- Key recommendations to improve the boiler’s operating efficiency and reliability.
A comprehensive report with recommendations was submitted to the client. They plan to implement some of the follow up work suggested/identified in the report as well as implement some of the recommended process changes.
- Specialty Chemicals Production
- Process utilities systems evaluation