دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a hard brown or black material composed principally of hydrocarbons. It is insoluble in water but soluble in gasoline and can be obtained by heating some petroleum, coal tar, or lignite tar. It is used for paving and roofing and in paints.

n: See lignite.

n: a compound in which chromium has a valence of 6, e.g., sodium bichromate. Chromate may be added to drilling fluids eimer directly or as a constituent of chrome lignites or chrome lignosulfonates. In certain areas, chromate is widely used as a corrosion inhibitor, often in conjunction with lime.

n: mined lignite, usually leonardite, to which chromate has been added or has reacted. The lignite can also be causticised with either sodium or potassium hydroxide.

n: See chrome lignosulfonate.

n: Mined lignite, usually leonardite, to which chromate has been added and/or reacted. The lignite can also be causticized with either sodium or potassium hydroxide. The chrome lignite is used for rheology stabilization and filtration control of the drilling

materials that reduce the fluid loss from a wellbore fluid. May include Bentonite clays, lignite, CMC, etc.

n: organic acids of indefinite composition in naturally occurring leonardite lignite. The humic acids are the most valuable constituent. See lignins.

n: a kind of crude organic macromolecule compound.

n: a naturally occurring oxidised lignite. See lignins.

n pi: naturally occurring special lignites, e.g., leonardite, that are produced by strip mining from special lignite deposits. Used primarily as thinners and emulsifiers.

n: The mineral leonardite, similar to brown coal. Lignite is found in surface deposits worldwide. Lignite is mined and put into piles where it can oxidize in the air before it is dried, ground and bagged for use in drilling fluids. The humic acid content of

very young coal. Moderate to low energy yield.