Sustainable, Long-Term Solution For MIC/SRB Corrosion In Hydrocarbon, Other Pipeline Systems

U-TECH
By Kent Weisenberg | July 2010 Vol. 65 No. 7
The MIC/SRB corrosion was a severe problem.

New type of additives
In the last several years, specific additives containing more permanent ammonium salts that become permanently polymerized within polymer-based systems were developed by Inspar formulators. This polymerization process is greatly enhanced within the Inspar polyurea systems, resulting in a matrix of ‘lance-like’ salt structures throughout the entire thickness of the high-build linings. These nano-sized structures pierce the cellular walls of microbes, resulting in the complete and effective death of the bio-organisms.

It is important to note that these salt structures are bio-compatible with sensitive applications such as drinking water, food contact and other health uses. Additionally, no heavy metals are used, and no arsenic is present in Inspar’s BioLine ‘anti-microbial’ formulations.

Lining Application
Inspar reviewed all design factors and data in calculating the required thickness of the liner. The analysis was first based on determining the safety factor pursuant to the wall loss of the schedule 40 carbon steel pipe in conjunction with the existing pressures in the system. The subsequent calculation also required the liner to span 3/4-inch perforations with a safety factor of three. The result, when combined with the linear mathematical expression formulated from prior burst testing, was the determination of a liner thickness of approximately 4 mm.

In this instance, the effluent bypass utilized an adjacent ballast pipeline. The pipeline was accessed from the existing flange breaks provided by the client. The Inspar lining systems require only one access to the pipe interior, a minimal lay-down area, and no impact on the surrounding area. Additionally, with umbilical-controlled robotics, the requirement for close proximity to the pipe access is unnecessary.

The lining product Inspar utilized for this project was StructrLine SS, a highly chemical- resistant, heat-resistant, semi-structural polyurea with Inspar’s BioLine additive. The use of StructrLine SS resulted in a tenacious bond to the host pipe and a liner that was cohesive with the substrate.

Eliminating annular space
Because of the liner’s full cohesiveness with the existing profiles in the pipe, there was no resulting annular space, as with other remediation methods the client had investigated. More importantly, the absence of this annulus prohibited the aqueous environment that the bacteria require for survival.