Total remodeling of a storage tank park after a serious problem of environmental contamination.
Common problems faced by storage tanks:
Above ground industrial storage tanks and their contents are extremely valuable assets that must be protected. There is a wide range of problems that can cause damage and deterioration to both storage tanks and the surrounding environments if left untreated. Prolonged exposure to adverse weather conditions and work environments can eventually affect such assets.
In our previous blog, Tank Coating, we highlighted these typical problems and the benefits of coating them in more detail. Ultimately, these types of problems can lead to structural damage, such as wall or ceiling defects and leaks.
Damage and deterioration occur not only on the tanks themselves, but also on the surrounding areas. Secondary containment or dike is designed to prevent spillage from a tank in the event of failure. However, a failure of this magnitude is costly and potentially dangerous. Loss of tank contents, disposal costs, clean-up costs and possible eventual removal of the tank itself can represent very significant losses and safety issues.
CASE STUDY – A DETERIORATION PROBLEM:
An Italy-based storage tank farm was used to store withdrawn machinery oil. After an intervention by the environmental public authority, contamination problems were detected within the site. Due to the gradual deterioration of the storage tanks from environmental damage and internal corrosion, the tanks and surrounding containment areas did not meet environmental standards. Therefore, the site required a complete redevelopment.
Belzona’s Italian distributor, BS SRL, was able to offer a complete turnkey solution to restore the deteriorating tank farm. Through a constant local presence, BS SRL was able to provide a reliable, long-term, high-quality technical proposal.
RESTORATION OF DEPOSITS WITH BELZONA:
- Internal:
The internal parts of the tank needed a suitable lining that could provide protection against the oils. Due to a mixture of water and hydrocarbons, the bottom of the tank (where the water settles) began to corrode. This is because the density of water is greater than that of hydrocarbons and since the steel is unprotected, the tank corrodes from the bottom.
Belzona 5811 (inmersion grade) was chosen due to its ability to provide protection to surfaces operating under immersion, while providing chemical resistance to oil.
The storage tank was drained and pressure washed to remove any loose contaminants and debris. Once dry, it was sandblasted before applying 2 coats of Belzona 5811 to the ‘floor’ surface and approx 1 meter up the internal walls.
- External:
For the external surfaces of the storage tank, the surface was re-blasted before applying 2 coats of Belzona 6111 (liquid anode) .This zinc-rich epoxy system acts as a long-term steel protection system for surfaces exposed to environmental corrosion. Belzona 6111 was followed by 2 coats of Belzona 5111 (ceramic cladding) due to its good UV resistance. The system also provides an aesthetically pleasing finish while providing long-term protection for the storage tank.
- Tank base:
The base of the storage tanks needed to be repaired and protected due to wear. Over time, moisture built up in the bell angle of the tank, causing corrosion. Tank base corrosion can also be caused by expansion and contraction of the tank or failure of mastic-type sealants.
Conventional sealing methods such as mastic tapes are subject to shrinkage and UV attack. These methods also do not allow moisture to escape. A solution needs to be implemented to allow trapped moisture to percolate, allow flexibility for expansion loading, and provide a long-term, durable solution.
The base of the tank first had to be regrown to the original surface due to loss of material over time. Had it been left untreated, the structural integrity of the tank base would have been at risk. Belzona 4111 (Magma-Quartz) was chosen to resurface the tank base. Unlike conventional methods, this repair compound is easy to mix and apply without the need for specialized tools. Downtime is also reduced due to the fast curing properties of the system.
For tank base sealing, Belzona 3111 (Flexible Membrane) was the ideal solution due to its microporous properties, flexibility and proven track record in long-term tank base protection.
This is the product mix used for this case study, but Belzona offers many more. If you need more information about Belzona solutions for sealing tank bases, we leave it to you at the link.
- Containment Areas:
Like the storage tanks, the surrounding containment areas failed to meet environmental standards due to damage.
The concrete floor surrounding the tanks had also gradually deteriorated over time. Some areas suffered a large loss of material, creating an uneven surface.
A solution was needed that would reduce downtime as well as offer exceptional compressive strength, good impact resistance and excellent bond to existing concrete. Belzona 4111 (Magma-Quartz) was chosen to resurface the concrete floor.
The total area that needed to be reformed was 1100m². Expansion joints were installed to allow the floor to expand and contract without cracking. Belzona 4521 (Magma-Flex Fluid) offered a high performance and cost effective alternative to conventional putties and sealants. The material demonstrates long-term flexibility and accommodates horizontal and shear movement by up to 25%.
The full result:
The storage tank park received a complete turnkey solution that complied with environmental standards, and for the long term. The implemented systems ensure that the useful life of the tanks is greatly extended, without the need for short-term maintenance.
Since their refurbishment, the storage tanks have been in service and running smoothly, resulting in real savings and an optimal solution for the customer.
If you have a similar problem, don’t hesitate to contact us! We will advise you without obligation: rodator@rodator.com