Shell Oil Comapny

Paul R Scott

Vitold R Kruka

Douglas E Broussard

Dean P Hemphill

Wilmer D Johnston

Jerome L Kyrish

A process and apparatus are provided for the simultaneous trenching and installation of submarine pipelines. The apparatus is based on a single unit which includes an excavating portion, an attached ditch sidewall retention shield, and a pipeline installation guide. The excavator creates a trench of a slightly larger cross section than required, the shield prevents the trench from closing due to the collapse of the sidewalls, and the pipe guide causes the pipeline to be deflected into that portion of the trench protected by the shield. The pipeline is fabricated on the surface of the sea or on floating ice, and is supported and guided to enter the forward portion of the shield by a stinger or other means, when required.

Underwater trencher with pipelaying guide

To remove particulate debris from a pipeline, a plug train including at least one gel plug having debris entraining characteristics and at least one pseudoplastic plug is passed through a pipeline and the debris is collected by the gel plug. The gel plug is pushed through the pipeline with a scraper which in turn may be pushed by liquid or gas pressure.

System for removing debris from pipelines

A polymeric foam pipeline pig, having its cells filled with a gel, is resistant to compression when subjected to pipeline pressure.

Pipeline pig

A gel plug of mineral oil, organo-modified smectite, and a particulate filler such as powdered coal, or a gel plug of mineral oil and organo-modified smectite is employed during construction of an off-shore pipeline to separate a gas-filled portion of the pipeline from a water-flooded portion, and to facilitate control and movement of a gas/gel plug/water interface as desired to assist in construction operations.

Pipeline gel plug

Liquid hydrocarbons are stored in salt dome caverns containing brine after first stripping the brine of contaminating gases such as oxygen and carbon dioxide by sparging a decontaminating gas such as nitrogen into the brine and removing the nitrogen and the contaminating gases from the salt dome cavern.

Storage of liquid hydrocarbons in salt dome caverns

A gel plug is employed during construction of an offshore pipeline to separate a gas-filled portion of the pipeline from a water-flooded portion, and to facilitate control and movement of the gas/gel plug/water interface as desired to assist in construction operations.

To remove fluid and/or particulate debris from a pipeline, a Bingham plastic fluid plug is passed through a pipeline and the fluid and/or debris are collected by the plug. The plug is pushed through the pipeline with a scraper which in turn may be pushed by liquid or gas pressure. Where the fluid to be removed is water, the Bingham plastic fluid plug employed preferably is a composition of water and a xanthan gum, and the gum may be cross-linked with a multivalent metal. Where the fluid to be removed is a hydrocarbon, the Bingham plastic fluid plug employed preferably is a composition of a mineral oil and an organo-modified smectite, and may also include a particulate filler such as powdered coal.

System for removing fluid and debris from pipelines

The evaporation of volatile non-aqueous liquids is inhibited by a floating layer of expanded cereal grains optionally treated with fluorocarbons or perlite treated with fluorocarbons.

Vapor barriers for liquid conservation

Water employed for the pipeline transmission of an oil core inside a water annulus is conserved by continuously recycling the water either for further use as a core flow fluid or for use in oil production.

Conservation of water for core flow

The adherence of oil to siliceous material, such as beach sand, is reduced by contacting the material with a blend of a primary long chain alcohol and an aliphatic solvent either before or after the oil contacts the siliceous material.

Growing community of inventors

Houston, TX, United States of America

Paul R Scott