Brenntag, a major business in the chemical distribution industry, appointed Equilibrant as Principal Designers to oversee the detailed design, procurement and project management of significant construction works at their Belfast depot under the NEC4 Option A contract.
The reinforced concrete Acid Tank bund contained 3no. large diameter acid containment tanks with diameters ranging from 14.6m – 16.3m and measuring between 9.4m to 9.7m high. The site also contained 1no medium sized tank Ø 9m x 10m high and 2no smaller tanks of Ø3.5m x 5.0 high and Ø3.5m x 5.3m high. Several plinths were also in place which did not support any tanks. The Acid Tank Farm is enclosed by a reinforced concrete bund wall and reinforced concrete floor slabs set at varying levels. The 200mm wide bund wall varies in height from approximately 1.5m high to 1.9m. A drainage channel located at the base of the internal perimeter bund walls appeared to drain to several sumps.
The concrete was suffering from extensive acid attack resulting in leakage and widespread deterioration. The site was not draining leading to advanced deterioration due to acid contaminated water.
Scope of works
Equilibrant combined inhouse knowledge of specialist surveying techniques, structural non-destructive testing and materials testing with procurement and project management expertise to deliver a complex refurbishment project. The innovative use of the “N4CE” software allowed the volumetric capacity checks to be completed to a high level of accuracy. The software was also used to design new floor levels within the bunded area to ensure optimal drainage falls were incorporated for durability which resulted in reducing bund capacity. A final volumetric capacity based on designed floor levels confirmed the capacity of the remedial works design was compliant with the strict standards required by the Petrochemical industry.