Spray coat comes to rescue

Each project required the Ferro Monk team to work closely with the contracted company and their client, to understand each project’s specific requirements. At Canvey Island and Spalding work was carried out on pumping stations that were suffering from hydrogen sulphide, which is produced as a result of anaerobic digestion.

When this occurs the bacterial attack of microorganisms breaks down biodegradable material in the form of sewage sludge.

It is colourless but toxic and responsible of eating away at concrete structures where sewage sludge is contained. The works had been identified through client surveys of the structures that had highlighted severe degeneration of the surface of the concrete through hydrogen sulphide attack. So acute was the problem at Canvey Island that the first layer of reinforcement was exposed and at risk of being corroded. If left unchecked, it could have resulted in a failure of the structure in the medium term.

Fortunately, the standard of design and construction of the basic structure was good and a surface repair was deemed appropriate. Had the Canvey Island site been left much longer, total reconstruction might have been necessary.

Although the structures were suffering from the same severe hydrogen sulphide problem, each project had its own specific requirements. The works at Canvey Island consisted of the treatment of the walls and soffit of a structure around 15m long, 4m wide and 7m deep.

Spalding’s wet well chambers were smaller, but just as complex in terms of shape and access.

Ultracoat is a ‘green’ product – 100% epoxy with no volatile organic compounds. It has a high safety value and can be applied in confined spaces with no risk of combustion to hazardous materials. It is also resistant to algae and bacterial growth. Ultracoat can be sprayed on to damp surfaces and applied quickly. Its high bond strength means it can strengthen corroded or weakened structures and it can adhere to most surfaces, including concrete, steel, brick, fibreglass and clay. It can be used on tanks, chambers, manholes and culverts. Ultracoat is ideal for use in damp environments. It bonds well and systems can be back in use within two hours after application. This was an essential factor in the success of all the projects.