The following article details improvements to the steam system at an oil-refinery terminal that resulted in significant energy system cost savings, better ownership of the asset by personnel, and improved plant operations.

Introduction

The project, located at a midwest petro-chemical terminal, began with a site operational reliability and energy savings assessment to identify opportunities for improvement. The facility was a mature operation that had undergone some ownership changes due to cyclical profits in that industry. The new owners had identified the need for a “due diligence” review to identify opportunities that would improve profits.

In this facility, several grades of industrial oil products were delivered to the terminal by rail from a refinery in the Gulf Coast region for local market distribution. Products were unloaded into numerous 50,000 to 500,000 gallon storage tanks, blended, heated, and then delivered to customers by tanker truck. The process was not at all complex, but most product grades were asphalt and roofing base stock that required heating. We were easily able to identify thermal inefficiency issues throughout the facility.

Identification of Opportunities

After the assessment, the following items were identified as places where improvements could be made:

• Flash steam and condensate losses;
• Oversize, uninsulated, atmospheric condensate tank;
• Uninsulated atmospheric deaerator unit;
• Uninsulated steam lines, valves and traps, and feed-water piping;
• A new process oil heater without heat recovery;
• Boiler efficiency and control issues; and
• Boiler and process heater fuel conversion options.

It is not unusual to identify these types of basic anomaly conditions at mature facilities that operate with a skeleton staff and on a limited budget. Unloading, blending, and shipping operations (to meet demanding customer schedules) can keep a crew fully occupied if the process does not operate smoothly.

Inspection Process

With the aid of schematic piping, instrument and electrical diagrams, and a few hand-held test instruments, we traced out the processes, documented conditions, and developed a list of issues. The facility made site energy costs for fuel and electricity available to develop the figures on the following page.

Major Benefits

• Tanks and piping insulation improvements savings: $102,000
• Boiler and steam system improvements savings: $98,000
• Convert boiler from diesel fuel to natural gas: $208,000

Total of these 3 areas: $408,000

Return on Investment (ROI): Less than 2 years

Several process control issues were also identified as production bottlenecks. Nearly all of the improvement projects had an ROI of less than 2 years.

Results

After the evaluation, a report was submitted to the facility’s corporate technical staff group for project approval and developing system improvements. Due to the remote location from corporate headquarters, it took nearly a year to get all of the jobs approved and the work completed. Once completed, the process-control improvements resulted in a more efficient terminal operation. Several other facilities have since been selected for similar operational reviews as a result.

Particularly for companies that operate mature industrial process plants that use a lot of steam, or have undergone many changes over the years and have encountered some process upsets, it may be advisable to consider a technical assessment by an independent expert. With the right expertise and testing instruments, it is possible to identify updates that can improve a facility and save hundreds of thousands of dollars.