Sphere Cleaning

Using the patented and proprietary Vaporganic® technology together with the Tidal Wave cleaning chemistry, Refined Technologies has successfully cleaned spherical and bullet shaped storage vessels in multiple refineries.

The Challenge

API Standard 653, which imposes regular inspections for storage tanks and spheres, presents refiners and terminal operators with special challenges when it comes to cleaning those tanks. These inspections and API Recommended Practice 577 (among others) require that inspectors enter the vessel to inspect welded seams and joints for signs of corrosion and fatigue. Storage vessels in the refinery will typically have a bottom layer of hydrocarbon sludge and a large open volume of noxious gas after being deinventoried. Because of the large volumes involved, traditional cleaning and degassing methods can leave residual components so follow-up cleaning is necessary, causing significant added cost and delays. The end result is that valuable storage is kept out of the hands of operations, planners and schedulers for an extended amount of time. Refined Technologies was recently asked to clean spherical natural gasoline storage tanks and propane bullets in large Gulf Coast and Midwest refineries. The Vaporganic process was preferred because of its ability to solubilize residual sludge and completely remove residual gas.

The Solution

Refined Technologies has used its Vaporganic cleaning process and Tidal Wave chemistry to clean and degas equipment, including storage tanks, on a variety of units in refineries across North America. The process is effective at removing both light and heavy oil from storage tanks in a very short time with minimal labor, while producing less effluent than other cleaning techniques.

Tidal Wave eliminates LELs, H2S, benzene and other dangerous gases by removing their hydrocarbon source and scavenging gas from the void space.

With a Kauri-Butanol value of more than 150 (ASTM D 1133-04), the Tidal Wave chemical has a very high solvency strength and is applied to the vessel as a saturated vapor using the Vaporganic process. The vapor allows a relatively small amount of chemical to contact a large volume of gas and the entire interior surface area of the tank. Scavengers in Tidal Wave encapsulate and remove the gas, while condensing Tidal Wave solubilizes and removes hydrocarbon from features of the tank. Cleaning in the vapor state produces less effluent than with other methods. Furthermore, effluent is easily treated on-site as slop oil and waste water.

A custom cleaning plan was developed for each tank cleaning project following these general steps:

  1. The vessel is heated with approximately 8500 lb/hr steam to raise the interior temperature above ambient.
  2. A calculated amount of Tidal Wave is injected into the steam as the vessel temperature is maintained.
  3. The vessel is allowed to cool as steam is gradually removed.

The entire process was complete in about 8 hours and manways were opened with no residual gas issues. In one case, a small amount of sludge residue on the bottom of the tank was removed using a fire hose from the manway. An entry permit was issued immediately after cleaning.

Refineries are using Refined Technologies’ patented products and services to gain a strategic advantage in the marketplace. In your daily operations meetings we encourage you to consider Strategic Chemistry®: the timely use of chemistry and planning, designed to improve operating margins.