07/03/2019

Sika supplied the abrasion-resistant system to improve the performance of a wastewater treatment site serving more than one million UK homes.

Howdon sewage treatment works is based in Wallsend in north Tyneside. Owned by Northumbrian Water and capable of treating up to 12,000 litres of wastewater per second, it is the largest site of its kind on England’s east coast between Edinburgh and the River Thames. With millions of people reliant on its sanitary provision, it is critical the plant’s infrastructure is successfully maintained if operations are to continue without disruption. Therefore, as part of a £15 million upgrade at the plant, sewer pipes, chambers and tanks required the application of a proven corrosion management system to improve long-term performance and structural integrity. Sika® MonoTop®  4400MIC proved more than up to the task.

Containing calcium aluminate chemistry, a vital ingredient that induces a ‘bacterio-static effect’ to inhibit acid generation at source, MonoTop®  4400MIC offers superior resistance to biogenic corrosion which can destroy up to 25mm of concrete per year. This dry-spray solution not only offers high abrasion resistance, post application its high early strengthening means services can be returned to operation after one hour. For the Howdon project, initial repairs carried out by contractors, CRL, involved applying the sewer pipes, chambers and tanks with SikaCem®-133 GP Gunite. The dry-sprayed micro repair concrete, which was applied at 30mm overlay, provides the ideal restorative solution for a range of structures including tunnels, bridges and fire-damaged buildings. MonoTop®  4400MIC was then applied. Due to its aluminate cement and aggregate composition, its elements combine to increase its excellent resistance to harmful sulphates.

The system adores water, which means it readily adheres to damp concrete surfaces and eliminates osmotic issues with epoxy or polyuria systems. MonoTop®  4400MIC’s rapid-apply qualities, coupled with its supreme curing time, meant CRL completed the Howdon project in three days, with the plant remaining fully-operational at all times. This simple, cost-effective solution has eradicated the debilitating effects of corrosion to guarantee the functionality of vital elements within the wastewater treatment plant. By eliminating the need for additional maintenance visits, MonoTop®  4400MIC well deserves its reputation as a robust, industry-leading concrete corrosion inhibitor.