PR-015-084508-R01 Contaminants in Sales Gas Pipelines Sources Removal and Treatment

Abstract

The objective of this project is to provide information about a problem material found in gas pipelines called "black powder". It is a mixture or a chemical compound of iron sulfides, iron oxides, dirt, sand, salts, chlorides, water, glycols, hydrocarbons and compressor oils, mill scale, or other materials. The most common constituents, iron compounds of sulfur or oxygen, are corrosion products. In addition to chemical formation, black powder can be formed by microbes normally found in gas pipelines. This material causes machinery, measurement, and pipeline maintenance problems. This research investigates the forms of iron sulfides, their characteristics, and methods of formation and whether the molecular form can be an indicator of the source of the material. A sampling protocol was developed for proper collection of materials for analysis. Seventeen corrosion samples were collected and analyzed for material constituents and microbial content. The results of this testing were anonymously tabulated in a database. Other tasks in this project include guidelines for removal, handling, and disposal of the material. It discusses symptomatic versus root cause treatments for the prevention and control of black powder, and the corporate culture necessary to manage the problem. It presents recently developed technologies for cleaning or treating a pipeline containing black powder, such as cleaning and anti-microbial agents containing THPS which dissolve iron sulfides, and the use of magnetic filtration. The final task describes concepts for identifying the location of black powder in an operating pipeline and places to look and methods to use to best determine the distribution of the material.