Salt Deposition Risk Monitoring

Challenge

Salt deposition in crude and FCC fractionator overheads and hydroprocessing effluent trains can lead to various operational problems. It is critical to identify when the unit is operating in a condition with a high risk of salt deposition. If unmitigated salt deposition occurs, it can lead to an increase in corrosion and equipment fouling/plugging. This can cause loss of integrity, leading to potential process safety and economic risks.

Users need to be able to present the results as a continuous signal, as “percent of time at-risk.” This can prove difficult when an engineer must manually analyze data that resides in multiple unaligned systems, including lab data. Before Seeq, a thorough analysis required engineers to manually combine data from multiple sources and enter it in a spreadsheet, spending hours or even days formatting data, filtering it, and removing anything non-relevant.

Solution

Seeq makes it easy to view lab data alongside process data without having to make any complicated, manual adjustments to combine them. Using the Seeq Formula tool, operators can quickly calculate salt deposition temperatures (SDTs) and can compare this data to acceptable limits defined by first principles models and acceptable safety margins. In addition, with the Seeq Deviation Search and Histogram functions, engineers can view “at-risk” results as a trended signal or histogram. These tools allow engineers to spend less time collecting and analyzing data and more time implementing improvements to reduce the amount of “at-risk” time.

Benefits

By quickly identifying times of “at-risk” operation, Seeq enables users to save money by minimizing lost production from fouling in trays, exchangers, or pipes, which would otherwise result in unplanned shutdowns due to accelerated corrosion. These unplanned outages can lead to many safety issues and result in millions of dollars of lost production opportunities (LPO). Seeq Tools can also help to predict future failure events, allowing for proper planning and less cost to fix equipment.

Data Sources

• Process Data Historian: OSIsoft PI, PHD, others
• Laboratory Analysis Data: SQL Database

Data Sources

Using Seeq, engineers can efficiently find and remove all non-relevant data from unit shutdowns, equipment out-of-service, or non-steady state modes of operations, such as start-ups and shutdowns, making the data analysis process faster, smoother, and more accurate.

Data Cleansing

Using Seeq, engineers can efficiently find and remove all non-relevant data from unit shutdowns, equipment out-of-service, or non-steady state modes of operations, such as start-ups and shutdowns, making the data analysis process faster, smoother, and more accurate.

Calculations and Capsules

Users can import lab data (H₂S, NH₃, and HCl concentrations) as well as process data (temperature) into Seeq programs. Working with the Seeq Formula, engineers and scientists can calculate salt deposition temperatures (SDTs) for NH₄HS and NH₄Cl, and then compare findings to acceptable limits calculated with first principles models. Finding and identifying high-risk periods and visualizing “at-risk” results as a trended signal and histogram is easy with Seeq Deviation Search.

Summarizing Results

Seeq operators are able to monitor the process for all high-risk operating periods with real-time updates in the Seeq Workbench Analysis and Organizer Topics. In addition, by documenting all steps of the analysis process in Seeq’s Journal, the analysis process can be evaluated in the future and improved upon over time, allowing for continuous improvement.