As technology advances, the quest for cost-effective, safe and lower impact (Eco-safe) products is more prevalent than ever. The pipeline industry is rethinking approaches to pipeline construction to use these new technologies to reduce costs exceed safety standards, and improve environmental conditions, according to an article in the September issue of Pipelines International.
This article states that one area of the pipeline construction industry that has used older technologies is the buoyancy control mitigation sector. Now, a new technology employing geotextiles is addressing an old issue.
On new pipeline construction projects, the buoyancy control mitigation sector usually relies on large weights that are placed on buried pipelines to keep the pipe down in areas of high water tables, flood plains, marsh/tidal areas, and in rivers and lakes.
The article notes that buoyancy control is important because pipelines are almost always evacuated of product (oil/gas/water) at some point in their life cycle. This product evacuation makes the pipelines extremely buoyant, and weights are required to keep the asset safely in place. In the case of natural gas pipelines and other gaseous product lines, buoyancy control is required for successful day-to-day operations.
The article state that, previously, the most common weights used on pipeline projects have been concrete set-on weights, with sizes ranging for pipe from 4in. to more than 42in. in diameter. This weight, while having an almost perfect shape to fit the pipe, is constructed of concrete, steel re-bar, welded wire mesh, and steel lifting hooks. Fabric pipe protection surrounds the areas that contact the pipe to protect the steel pipe coating from the abrasive concrete. In many cases, these weights are constructed remotely and transported to site at great cost.
Cost-effective, safe, environmental pipeline weighting
An alternative technology to the concrete set-on weight is the geotextile pipeline weight (GPW). The GPW is constructed of polypropylene geofabric and local gravel or rock. The product is custom-built to fit all pipe sizes. This proven design and ease of handling makes the GPW a modern solution to several draw backs of the past, according to the article. Consider these three:
- Eco-cost (cost-effectiveness): In most cases, the filled GPW is less expensive than the concrete version due to the cost of the materials used in the final product. Because the GPW is made of gravel and fabric, there is no need for extra energy used for the mixing of concrete, hauling of steel, and manipulating of finished weights. The GPW is simply filled and ready to install on the pipeline.
- Eco-safe: The GPW product is safer to manufacture, handle, and install on pipeline construction sites.
- Eco-responsible (environmentally responsible): The GPW is an environmentally safe solution. The fill gravel or rock is often used from local sources and therefore has minimal effect on introducing non-indigenous materials to the construction site. This means that potential leaching or runoff from the GPW is more environmentally friendly than those transported from other sites. Also, polypropylene geotextiles are inert when buried, and has virtually zero leaching effects.
The article concludes that GPW provides a good solution to reducing the problem of introducing too many foreign materials into the environment. In this way, the product helps to reduce the carbon footprint of a pipeline project.