The project developed a modelling approach to predict the effectiveness of nano-composite barrier systems against permeation and leaching upon processing. The main need for the innovation was centered around the essential barrier property of a pipe for two principal markets:
- Unbonded Flexible Pipes (UFPs) for the oil exploration industry
- Potable water pipes for Brownfield sites.
The primary market, Unbonded Flexible Pipes (UFPs) for the oil exploration industry, which have a design life of 25 years, has a strong need to reduce permeation of hydrocarbons and other substances (particularly H2S, CO2, CH4 and H2O) into the layered metallic pipe structure. This causes corrosion of the steel layers affecting the pipe structural integrity. The current manufacturing method of choice to overcome the corrosion problem and achieve the 25 years design life of the pipe is to oversize the barrier layers. Whilst addressing the barrier problem, the thick barrier layer causes other problems: the effects of creep and fatigue increase due to excessive weight, again potentially shortening its life and presenting a risk of catastrophic failure.
The secondary market is for potable water pipes where there is a specific need to reduce the risk of hydrocarbons permeation from contaminated land into the water supply. This situation tends to occur where property development takes place in Brownfield sites. The need for barrier plant is determined by soil analysis along the proposed route of the pipeline. Barrier pipe is also used in areas with a high risk of hydrocarbon contamination (e.g. near petrol stations or gas storage). In these locations, barrier pipes are laid 50m either side of the potential source of contamination as a precautionary measure.
Current methods using multi-layered polymer & metal pipes are costly and limiting. The key innovation of the Nanopipe project was the definition of a process producing thousands of layers of aligned nanoclay platelets in the pipe body dramatically reducing permeation and leaching.
Project deliverables were the creation of a model based on the process parameters to predict the alignment and distribution of platelets in polymers, the development of compounding processes and extrusion technology to produce dispersed, exfoliated and aligned nanocomposite layers within the polymer matrix, the development of an online monitoring system to check the distribution and morphology of the nanoparticles in the matrix and the adaptation of co-extrusion dies to accommodate the new approach.