A method for producing hydrocarbons includes the steps of a) providing a source of liquefied natural gas (LNG), b) regasifying the LNG at the well, c) pressurizing the regasified LNG above the formation pressure, d) injecting the pressurized LNG into the well, e) allowing the injection stream to flow into the producing formation, and f) recovering and transporting the regasified LNG and produced gas from the formation. The injection stream may include at least 85% methane and no more than 5 PPM water. Step f) may be carried out without separating the recovered gases. Step d) may continue for at least 24 hours. Step b) may comprise passing the LNG through a vaporizer. Step c) may be carried out before step b). An apparatus for injecting regasified LNG into a hydrocarbon formation may comprise an LNG tank, a vaporizer, a compressor, and a fluid connection to the producing formation.

A pneumatic timing valve includes a spool and seal system having a first seal cartridge and a spool. The first seal cartridge has an annular body with radial ports. The spool is positioned within the first seal cartridge and movable between a first and second position. The spool has a central bore and radial ports that intersect the central bore. The radial ports of the spool complement the radial ports of the seal cartridge. The seal cartridge radial ports, the spool radial ports, and the central bore of the spool define fluid flow passages.

The invention relates to a method of well rehabilitation using CO2. The improvement comprises providing a more effective distribution of effective energy throughout the entire well structure including all parts of the producing interval of the well and surrounding formation and distributing energy throughout the entire well structure. The improved method is obtained by controlling CO2 phase changes during CO2 injection to cause surging agitation within the well bore and surrounding formation and allowing CO2, mechanical energy and optionally chemical energy to reach substantially all area of the well.

Hydrocarbon wells including crosslinked polymer granules as lost circulation material and methods of drilling the hydrocarbon wells. The hydrocarbon wells include a wellbore that extends within a subsurface region, a drilling rig, a drilling mud supply system, a lost circulation detection structure, and a lost circulation material supply system that includes a lost circulation material. The lost circulation material includes a plurality of crosslinked polymer granules, and a characteristic dimension of each crosslinked polymer granule is at least 20 micrometers and at most 1 millimeter. Each crosslinked polymer granule contains a highly crosslinked polymeric material that includes a plurality of polyethylene polymer chains. The methods include rotating a drill string to extend a length of a wellbore and, during the rotating, flowing a drilling mud stream. The methods also include detecting a lost circulation event and, responsive to the detecting, providing a lost circulation material to the wellbore.

A method for stimulating production of hydrocarbons from a sandstone formation includes the steps of injecting a stimulation fluid into the sandstone formation, the stimulation fluid formed from a hydrofluoric acid precursor and an oxidizer; injecting an ammonium containing compound into the sandstone formation; and injecting a nitrite containing compound into the sandstone formation. The method further includes maintaining the stimulation fluid, the ammonium containing compound, and the nitrite containing compound in the sandstone formation to initiate reaction of the ammonium containing compound and the nitrite containing compound to generate heat and nitrogen gas, where upon generation of heat within the formation the hydrofluoric acid precursor and the oxidizer react to form hydrofluoric acid in-situ to dissolve silica and silicate minerals and stimulate the sandstone formation. A treatment fluid for use in stimulating sandstone formations includes the stimulation fluid, the ammonium containing compound, and the nitrite containing compound.

Method for production of hydrocarbons from shale oil reservoirs via a cyclic injection and production process. The method determines the composition of injected hydrocarbon-containing composition to be injected, performing injection and production steps, and then re-determines the composition of the injected hydrocarbon-containing composition to be injected.

Methods of fracturing a subterranean formation containing a hydrocarbon include introducing a first fracturing fluid that includes natural gas into the formation at a rate and pressure sufficient to create a complex fracture in the formation; introducing a second fracturing fluid into the formation, wherein the second fracturing fluid comprises water, a gelling agent, a foaming agent, natural gas, and proppant particulates; and allowing the second fracturing fluid to transport a portion of the proppant particulates into the complex fracture.

Disclosed are compositions and methods for the pressure protection of existing wells during infill drilling operations.

Disclosed are compositions and methods for the pressure protection of existing wells during infill drilling operations.

Disclosed are compositions and methods for the pressure protection of existing wells during infill drilling operations.