Blockage removal apparatus and method

A method of removing a blockage from a fluid conduit in a hydrocarbon production or transportation system, the method comprising:

• providing an apparatus comprising a first portion containing a fluid volume separated from the fluid conduit via a controllable valve;
• pressurizing the first portion of the apparatus to a first fluid pressure;
• cyclically opening and closing the controllable valve such that a pressure differential between the first portion and the fluid conduit causes a series of pressure pulses to be transmitted into the fluid conduit to the blockage, thereby causing a pressure change in the fluid conduit between the apparatus and the blockage;
• subsequent to the transmission of at least one pressure pulse into the fluid conduit, measuring a fluid pressure in the fluid conduit;
• and
• adjusting a fluid pressure in the first portion of the apparatus in response to a measured change in pressure conditions in the fluid conduit to maintain the pressure differential across the controllable valve within a preferred range and maintain a desired amplitude of the pressure pulses of the series.

Apparatus for removing a blockage from a fluid conduit in a hydrocarbon production or transportation system, the apparatus comprising:

• a first portion containing a fluid volume;
• a connector for coupling the first portion to the fluid conduit;
• a controllable valve disposed between the first portion and the connector;
• at least one pressure sensor for measuring a fluid pressure in the fluid conduit;
• a control module for opening and closing the valve;
• and
• a fluid pressure regulator configured to control the fluid pressure in the first portion in response to a signal from the pressure sensor;
• wherein the apparatus is configured to monitor a change in pressure conditions in the fluid conduit, and is further configured to compensate for a measured change in pressure conditions in the fluid conduit by adjusting a fluid pressure in the first portion of the apparatus.

A hydrocarbon production or transportation system comprising a fluid conduit and an apparatus for removing a blockage from the fluid conduit coupled to the fluid conduit, the system comprising a first portion containing a first fluid volume;

• a controllable valve disposed between the first portion and the fluid conduit;
• a pressure source for providing pressurised fluid to the first portion;
• a control module configured for opening and closing the valve to allow pressure pulses into the fluid conduit;
• pressure sensing means for determining a pressure differential across the controllable valve;
• and
• a fluid pressure regulator configured to control the fluid pressure in the first portion in response to a signal from the pressure sensing means;
• wherein the system is configured to monitor a change in pressure differential across the controllable valve, and is further configured to compensate for a measured change in pressure differential across the controllable valve by adjusting a fluid pressure in the first portion of the apparatus.

Apparatus for removing a blockage from a fluid conduit in a hydrocarbon production or transportation system, the apparatus comprising:

• a first portion containing a fluid volume;
• a connector for coupling the first portion to the fluid conduit;
• a controllable valve disposed between the first portion and the connector;
• at least one pressure sensor for measuring a fluid pressure in the fluid conduit;
• a control module for opening and closing the valve;
• and
• a fluid pressure regulator configured to control a fluid pressure in the first portion in response to a signal from the pressure sensor;
• wherein the apparatus is configured to cyclically open and close the controllable valve such that a pressure differential between the first portion and the fluid conduit causes a series of pressure pulses to be transmitted into a fluid conduit to a blockage, thereby causing a pressure change in the fluid conduit between the apparatus and the blockage;
• and
• wherein the apparatus is further configured to maintain the pressure differential across the controllable valve within a preferred range by adjusting a fluid pressure in the first portion of the apparatus in response to a measurement of the pressure change in the fluid conduit.

A hydrocarbon production or transportation system comprising a fluid conduit and an apparatus for removing a blockage from the fluid conduit coupled to the fluid conduit, the system comprising:

• a first portion containing a first fluid volume;
• a controllable valve disposed between the first portion and the fluid conduit;
• a pressure source for providing pressurised fluid to the first portion;
• a control module configured for opening and closing the valve to allow pressure pulses into the fluid conduit;
• pressure sensing means for determining a pressure differential across the controllable valve;
• and
• a fluid pressure regulator configured to control a fluid pressure in the first portion in response to a signal from the pressure sensing means;
• wherein the system is configured to cyclically open and close the controllable valve such that the pressure differential between the first portion and the fluid conduit causes a series of pressure pulses to be transmitted into the fluid conduit to the blockage, thereby causing a pressure change in the fluid conduit between the controllable valve and the blockage;
• and
• wherein the system is further configured to maintain the pressure differential across the controllable valve within a preferred range by adjusting the fluid pressure in the first portion in response to a measurement of the pressure change in the fluid conduit.