Characterization and evaluation of corrosion damage in refineries is of critical importance due to the need for safety, reliability, throughput and operational integrity for plant facilities. Appropriate corrosion assessment, prediction, ionic modeling/analyses and monitoring have the potential to eliminate expensive failures, minimize damage to the environment, and eliminate abnormal situations that can restrict asset availability.
The most significant issues when evaluating corrosion damage to refinery equipment and installations are the dominant mechanisms of deterioration and failure related to corrosion damage. Corrosion damage, in turn, requires a clear understanding of the role of equipment metallurgy and dominant corrosion mechanisms such as naphthenic acid corrosion, sour water corrosion, ammonium chloride effects, corrosion due to cyanides, amine corrosion, etc., as well as relevant cracking concerns such as carbonate cracking, hydrogen induced cracking (HIC), stress oriented hydrogen induced cracking (SOHIC), and sulfide stress cracking (SSC).
The ability to characterize the potential for corrosion and cracking damage and to use such knowledge to monitor and control corrosion will allow the refiner to "Enhance the Reliability" by proactively managing corrosion versus conventional methods whereby plant personnel act reactively to corrosion issues.
An integrated corrosion management solution that incorporates thermodynamic, process and corrosion modeling tools (collectively referred to as Modeling) can be used effectively to manage refining corrosion problems. Such a solution is designed to allow the plant to identify critical spots in the operations from a corrosion standpoint and have the ability to run refinery processes within appropriate system boundaries to ensure safe unit operations. Once corrosion is effectively being managed the resulting data and information can be easily integrated to Asset and Boundary Management applications to link process and corrosion management to operations allowing to:
Understand when operating conditions cause an adverse impact on corrosion
Enable Operators' awareness about critical limits (for process and corrosion)
Set appropriate alarms according to identified limits for corrosion and other relevant, critical parameters
Alert plant management about the impact of deviations on equipment reliability, as well as plausible remediation paths to address the deviations
Align with the site's management of change process to approve any changes to operations when deviation from limits occurs
Monitor critical boundaries (Integrity Operating Windows), enabling operator comments on causes and corrective actions for deviation Validate material performance, chemical/neutralizer injection, water wash, inspection frequencies and locations, monitoring locations, etc Achieve the benefits of enhanced asset integrity, i.e., reduced cost of maintenance, inspection, turn-around, failure-risk, improved reliability, safety and efficiency
This corrosion and asset integrity methodology represents a life-cycle based approach to corrosion control, and integrates multiple, comprehensive components of corrosion control in a complementary closed-loop control framework.
Reader Tip Provided by: Juan P. Hernandez, Advanced Solutions Leader - Honeywell Corrosion Solutions