Effects of Black Powder in O&G and How to Prevent Them
March 10, 2020 Welcome
One of the most serious issues facing the oil and gas manufacturing industry is the formation of black powder. This corrosive substance is responsible for significant damage to process components including pipeline networks.
The damage caused by this substance has undesirable implications for production costs and efficiency, necessitating preventive measures.
In this article, we outline the effects of black powder on the oil and gas production process and consider techniques required to eliminate it.
What Is Black Powder in the Oil and Gas Industry?
Black powder is a corrosive substance formed by the reaction of water, carbon dioxide, and sulfur-containing compounds with steel. This compound is a commonly occurring side effect of the transport of oil and gas via steel pipelines. Black powder typically consists of fine contaminants (1-10 microns) that can be easily dispersed throughout a pipeline network causing damage.
What Are the Components of Black Powder?
The typical composition of black powder is iron oxides (pyrrhotite, mackinawite, marcasite, and pyrite) which rapidly occlude fluid transport channels if left unchecked. The chemical components which cross-react with steel to produce black powder include:
- Hydrogen sulfide
- Carbon monoxide
Effects of Black Powder
The formation of black powder within gas pipelines has undesirable effects on overall process efficiency and productivity. Apart from damaging industrial equipment, it also poses a significant safety risk as it is easily combustible. These and other critical effects of black powder deposition are discussed below.
Reduction in Pipeline Diameter
Despite having fine particles, black powder can build up within pipelines and fluid reservoirs if left unattended. The gradual deposition of black powder will narrow the lumens of wellbores as well as gathering lines and larger transmission lines, reducing fluid pressure and flow. This narrowing will diminish process efficiency and necessitate costly maintenance and downtime.
Accelerated Metal Component Erosion
The physical properties of black powder make it tougher than the steel material used in manufacturing pipelines and other equipment used in oil and gas. The implication is that the presence of black powder within this equipment will accelerate the rate of degradation.
In addition to carbon steel pipelines, black powder corrosion will damage various components including flow meters, air compressors, regulatory valves, and nozzles.
Increased Risk of Combustion
Due to its unique chemical composition, black powder is easily combustible, especially in its powdered form. When combined with the volatile nature of hydrocarbons being recovered during oil and gas production, black carbon accumulation poses a serious industrial safety risk.
Black Powder Removal Techniques
Different commercially feasible techniques have been developed to reduce the effects of black powder in oil and gas processes. Depending on operator preferences and well configuration, one of the methods outlined below can satisfactorily eliminate black powder from the production process.
Cartridge filters are available in materials ranging from cellulose to glass fiber and propylene. Concerning their performance, cartridge filters can be designated as nominal and absolute filters.
While nominal filters may display imperfect filtration when there is a drop in flow pressure, absolute filters remain efficient even when there are variations in working pressure. Highly efficient absolute filters will trap black powder particles in the range of 1-10 microns consistently.
Cyclonic Separators & Cartridge Filters
A combination of cyclonic separators and cartridge filters is effective in eliminating black powder from industrial pipelines. This unique technology will remove particles in an efficient two-step sequence. First, a low-speed cyclone system will eliminate particles in the order of 5-10 microns after which high performance, absolute filters will remove the remainder of the particles thus meeting process specifications.
Liquid/Gas Coalescing Systems
In cases where black powder is suspended in a stream of mixed liquids and gas, the most effective method of elimination is using coalescing filters. Liquid/gas coalescing devices eliminate aerosols by forming a larger whole that be cleanly separated. Liquid/gas coalescers have pilot units that can be subjected to a slipstream of pipeline gas. Data collected can be analyzed and used to fine-tune future filtration processes.
Liquid/Liquid Coalescing Systems
Liquid/liquid separation units are employed in cases where both fluids are in the liquid from. These coalescers have been used to effectively eliminate brine and other hydrocarbons from liquefied natural gas.
Liquid phase separators are typically coupled with pre-filtration units that help breakdown emulsion contaminants thereby prolonging their useful life span. Like liquid/gas coalescers, liquid/liquid systems also have pilot units that provide valuable data to operators.
IFS Can Help Prevent Black Powder Corrosion
At Integrated Flow Solutions, we are dedicated to providing clients with the best modular process skids for black powder removal. For project operators looking to eliminate pyrrhotite from their oil and gas applications, IFS provides the best quality black powder separators.
Contact us today for a quote or to learn more about the full range of oil and gas industry solutions we provide.