CLIENT: Dubai Supply Authority, DUBAI, UAE
Black Powder has become a more widely recognized hazard for safe and economic gas pipeline operation. Black powder is a generic name for small-particle ferrous corrosion by-product.
Much discussion has been going on as to the causes and sources of the problem, but in general the following roots of the problem can be discerned:
– Sour gas services. Higher levels of hydrogen sulfide cause the formation of iron-sulfides in the pipeline.
– Moisture. Water that remains from the hydro test phase or that is present as a result of wet gas, leads to formation of iron-hydroxides and iron oxides in the pipeline.
– Mill scale deterioration. In older and uncoated pipelines, mill scale may be of poor quality and in the process of pipe manufacturing disbandment may be initiated.