Innovative Cleaning Solution for Sulfuric Acid Bundles

Hands Free™ Chemical Exchanger Cleaning

CUSTOM CLEANING METHOD RESTORES SULFURIC ACID HEAT EXCHANGER TO 100% CAPACITY

Veolia was asked to clean a large heat exchanger at the Red Lion sulfuric acid regeneration plant in Delaware. The vertical heat exchanger was 55 feet long, 12 feet in diameter and held 1,614 1.5'' tubes. The build up of sulfuric acid residuals inside the tubes reduced the unit's heat efficiency and limited overall plant production capacity. 


The plant's previous cleaning method was not effective and required dangerous, manual dry cleaning methods that were only capable of cleaning 10-15% of the internal tube surfaces. It is a general practice within the industry to use high pressure water as a cleaning agent. However, when water combines with sulfuric, the solution becomes highly corrosive and emits NOX and SO2 gases. These emissions are very dangerous for workers and the environment, and the solution causes tube damage to the bundle, reducing heat transfer rates and shortening the exchanger's life. 

Veolia was challenged to develop an innovative and cost-effective cleaning solution that would return to the exchanger to full capacity, without damaging the bundles or compromising the safety of workers or the environment. 

VEOLIA'S SOLUTION

Veolia's technical and operational experts designed a ground-breaking and patent-pending cleaning process for these exchangers that utilized mineral oil as the cleaning agent. Mineral oil has similar cleaning properties to water, but is not reactive with sulfuric, eliminating the corrosion and emission issues that plagued one of the plant's previous cleaning processes. 

Once Veolia's chemical analysis was tested internally and validated to be effective on sulfuric bundles, Veolia identified the mix of technologies in its Touch Free portfolio that could be utilized to eliminate the significant hazards of manual cleaning. Veolia used Touch Free lancing tools, specialty nozzles, and a high-volume pump to clean the exchanger, pumping thousands of gallons of mineral oil through the bundle and then filtering and recirculating it through the exchanger to continue the process. 

By combining the mineral oil cleaning solution, Touch Free tooling, and custom-designed nozzles, Veolia was able to safely and effectively restore this exchanger to 100% capacity in only 9 days, without emission issues or the need for scrubbers. Infrared cameras were also used to eliminate confined space entry to monitor cleaning progress and inspect the condition of the tubes. Veolia was able to manage the hazardous waste generated by the cleaning process, self performing the transportation and processing at its own facility in Middlesex, New Jersey. 

RESULT

Veolia's innovative Touch Free cleaning solution was a game-changer that addressed all of the customer's concerns: protecting workers' safety, increasing plant efficiency, and effectively minimizing project waste, while preventing the production of VOCs. Veolia's use of Touch Free tooling helped prevent workplace injuries while ensuring the highest level of cleaning results for the customer. 

Additionally, the non-reactive cleaning process minimized corrosion and erosion within the exchanger tubes. Veolia's method helped extend the life of the bundle, minimizing downtime and delaying approximately $3 million in capital expense to replace the bundle. 

After cleaning and for the first time since the plant was commissioned, the exchanger was able to run at 100% capacity. The plant realized an immediate increase in heat transfer. This allowed them to increase sulfuric acid production by 15%, producing an additional 40 tons on a daily basis. With sulfuric valued at $200/ton, this productivity uptick has had significant financial benefits for the customer.

Veolia's use of infrared cameras eliminated the requirement of confined space entry to monitor the cleaning process. This technology provided the customer with the valuable opportunity to assess the internal condition of the exchanger for the first time, alogn with being able to monitor the progress of Veolia's cleaning. In total, this patent-pending Touch Free cleaning solution for sulfuric bundles delivered more than $2.5 million in hard cost savings and approximately $3 million in soft cost savings for the customer. 
 

"Veolia provided this sulfuric acid regeneration customer with an innovative exchanger cleaning solution that substantially increased heat efficiency and raised production by 15%, while protecting workers and the environment." 
-Donald Glover, General Manager, Gulf Coast