Black powder formation in natural gas pipeline networks: associated issues and root cause analysis

The natural gas is touted as one of the clean energy sources, widely used in industries and domestic applications. It is transported through a network of pipelines. The presence of different types of contaminants, such as solid particles, traces of chemicals, and free water (moisture), in these pipelines could lead to different types of operational and hazardous issues. Especially, solid contaminants known as “black powder” found in natural gas transmission and distribution systems are a leading cause of concern in the global natural gas industry. The black powder is a byproduct of corrosion on the pipeline, mainly due to environmental or microbial actions. It is a mixture of iron sulfides, oxides, and carbonates and can represent a serious threat to the integrity of pipelines due to plugging pipes, plugging and collapse filters, eroding compressor components and control valves, metering lines, plugging instrumentation and pipeline drips, preventing valid inline inspection (ILI) by ILI pigs, failures in gas treatment plants, and causing damage to customer equipment. Gas industry is suffering from major issues associated with this problem and ends up losing a lot of revenue. Therefore, understanding its physical, chemical, and microbial characteristics and providing a relevant solution are necessary for pipeline operators and gas companies in order to consider the appropriate mitigation strategies.