REMOVAL OF ORGANIC IMPURITIES FROM WATER

摘要

The present disclosure relates to the hydrostatic testing of pipelines and to purification of waste water from such testing. More specifically, there is provided a method of hydrostatically pressure testing a natural gas pipeline using water. The waste water, which is contaminated with hydrocarbons, is subsequently treated by contacting it with manganese dioxide so that the hydrocarbons are broken down into carbon dioxide and water.

主权项

1. A method comprising:
(a) hydrostatically pressure testing a natural gas pipeline using water wherein said water becomes contaminated with hydrocarbons; (b) recovering the hydrocarbon contaminated water used in the test; (c) introducing the hydrocarbon contaminated water into a separator to remove hydrocarbons that are above solubility limits to thus produce a hydrocarbon stream and a first recovered water stream having a pH from 6 to 8, wherein the first recovered water stream contains dispersed hydrocarbons below the solubility limits; (d) lowering the pH of the first recovered water stream to be in the range of from 0 to 5 to produce an acidic water stream; (e) converting at least part of the dispersed hydrocarbons in the acidic water stream to carbon dioxide and water to produce a second recovered water, wherein the converting includes contacting dispersed hydrocarbons with a conversion compound such that at least a portion of the dispersed hydrocarbons are converted, and wherein the first conversion compound comprises manganese dioxide; (f) increasing the pH of the second recovered water stream to from 8 to 12 to precipitate out resulting solids to thus produce a third recover water stream and the solids; and (g) recycling said second recovered water to be used in additional hydrostatic pressure testing, wherein steps (a) through (e) are carried out in a contained system such that hydrocarbons are not vented to the atmosphere.