A method of pumping material from a sea floor to a vessel on a sea surface, including the steps of collecting material from the sea floor using a production tool, connecting the production tool to the vessel with a riser including a riser transfer pipe, and pumping the material from the production tool to the vessel using a subsea slurry lift pump positioned between the production tool and the vessel and attached to the production tool by the riser transfer pipe. The method further includes backflushing the riser transfer pipe by running seawater through the slurry lift pump into the riser transfer pipe toward the production tool.

A system including a fluid injection system configured to removably couple to a mineral extraction system, wherein the fluid injection system includes a fluid injection system controller, a flow meter system coupled to the fluid injection system controller, wherein the flow meter system is configured to measure a fluid flow of a fluid through the fluid injection system, an adjustable valve configured to control the fluid flow through the fluid injection system, and a non-return valve configured to block reverse flow of the fluid through the fluid injection system, wherein the fluid injection system controller, the flow meter system, the adjustable valve, and the non-return valve are coupled to a common housing.

A system including a fluid injection system configured to removably couple to a mineral extraction system, wherein the fluid injection system includes a fluid injection system controller, a flow meter system coupled to the fluid injection system controller, wherein the flow meter system is configured to measure a fluid flow of a fluid through the fluid injection system, an adjustable valve configured to control the fluid flow through the fluid injection system, and a non-return valve configured to block reverse flow of the fluid through the fluid injection system, wherein the fluid injection system controller, the flow meter system, the adjustable valve, and the non-return valve are coupled to a common housing.

A compressor system includes a compressor (50) configured to compress a gas, a compressed gas circulation unit (52) in which a gas compressed by the compressor (50) circulates, a hydrate anti freezing agent supply unit (53) configured to supply a hydrate anti freezing agent for preventing hydration of the gas to the compressed gas circulation unit (52), a compressor hydrate anti freezing agent supply unit (54) configured to supply part of the hydrate anti freezing agent supplied from the hydrate anti freezing agent supply unit (53) to the compressor (50), and a pressure changing unit (59) configured to change a pressure of the hydrate anti freezing agent inside the compressor (50).

The pipe includes at least one tubular sheath delimiting a passage for circulation of the abrasive material, at least one tensile armor layer externally positioned with respect to the tubular sheath, the armor layer including a plurality of filiform armor elements. It further includes a protective internal layer positioned inside the tubular sheath in the circulation passage, the protective internal layer including an elastomeric matrix and a longitudinal reinforcement assembly embedded in the matrix.

The pipe includes at least one tubular sheath delimiting a passage for circulation of the abrasive material, at least one tensile armor layer externally positioned with respect to the tubular sheath, the armor layer including a plurality of filiform armor elements. It further includes a protective internal layer positioned inside the tubular sheath in the circulation passage, the protective internal layer including an elastomeric matrix and a longitudinal reinforcement assembly embedded in the matrix.

Amines and amine derivatives that improve the buffering range, and/or reduce the chelation and other negative interactions of the buffer and the system to be buffered. The reaction of amines or polyamines with various molecules to form polyamines with differing pKa's will extend the buffering range, derivatives that result in polyamines that have the same pKa yields a greater buffering capacity. Derivatives that result in zwitterionic buffers improve yield by allowing a greater range of stability.

This invention relates to deep-water underwater transportation in mining operations, and can be used for the placement of geological survey and mining equipment. The present underwater transport module comprises a body (1), ballast tanks (2) with adjustable buoyancy, and a system (3) for pumping a working medium in and out, said working medium being water from outside the transport module. According to the invention, the body (1) has a streamlined shape and is made of syntactic foam (a composite based on hollow glass microspheres), the ballast tanks (2) are configured in the form of a multi-tiered ballast system comprised of a plurality of spherical vessels (4), each of which consists of two interconnected hemispheres (5), the cavities (6) of the spherical vessels (4) being connected to one another and to the system (3) for pumping a working medium in and out, and the underwater transport module further comprises hydraulic propellers (7) for cruising and maneuvering, said propellers being connected to the system (3) for pumping a working medium in and out. The invention provides for the reliable and environmentally friendly use of a transport module at great depths as a result of enhanced durability, buoyancy and maneuverability.

Amines and amine derivatives that improve the buffering range, and/or reduce the chelation and other negative interactions of the buffer and the system to be buffered. The reaction of amines or polyamines with various molecules to form polyamines with differing pKa's will extend the buffering range, derivatives that result in polyamines that have the same pKa yields a greater buffering capacity. Derivatives that result in zwitterionic buffers improve yield by allowing a greater range of stability.

A seafloor haulage system (10), for lifting seafloor materials from the seafloor to the surface, that has a line member (150), preferably synthetic rope, that extends at least partially between the seafloor and the surface and a container (400), preferably a plurality of containers, capable of carrying a load connected to the line member (150). The containers have a steerable element (410), such as a rudder, that enables the container to manoeuvre as it is propelled, typically towed by the line member, through the water.