Hydrogen compressor
Encyclopedia
A hydrogen compressor is a device that increases the pressure of hydrogen
by reducing its volume. Compression of hydrogen gas naturally increases its temperature, due to Charles' Law.
Hydrogen compressors are closely related to hydrogen pumps and gas compressor
s: both increase the pressure on a fluid
and both can transport the fluid through a pipe
. As gases are compressible, the compressor also reduces the volume of hydrogen gas, whereas the main result of a pump raising the pressure of a liquid
is to allow the liquid hydrogen
to be transported elsewhere.
-metal diaphragm compressor
s are stationary high-pressure compressors, 4-staged water-cooled, 11~15 kW 30~50Nm3/h 40MPa for dispensation of hydrogen. Since compression generates heat, the compressed gas is to be cooled between stages making the compression less adiabatic
and more isothermal. The default assumption on diaphragm hydrogen compressors is an adiabatic efficiency of 70%. Used in hydrogen station
s.
, is a hydrogen compressor based on a ionic liquid
piston instead of a metal piston as in a piston-metal diaphragm compressor
.
(GRC) is a positive displacement rotary compressor
based upon an envoluted trochoid geometry which utilizes a parallel trochoid
curve to define its basic compression volume. It has a typical 80 to 85% adiabatic efficiency.
uses dynamic counterbalancing, where an auxiliary movable mass is flexibly attached to a movable piston assembly and to the stationary compressor casing using auxiliary mechanical springs with zero vibration export at minimum electrical power and current consumed by the motor. It is used in cryogenics
, thermal and pressure properties of a hydride
are used to absorb low pressure hydrogen gas at ambient temperatures and then release high pressure hydrogen gas at higher temperatures; the bed of hydride is heated with hot water or an electric coil.
incorporates a series of membrane-electrode-assemblies
(MEAs), similar to those used in proton exchange membrane fuel cell
s, this type of compressor has no moving parts and is compact. With electrochemical compression of hydrogen a pressure of 5000 psi is achieved. Pressure is believed to go beyond 10,000 psi to the structural limits of the design. A patent is pending for an exergy efficiency
of 70 to 80% for pressures up to 10,000 psi or 700 bars
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
by reducing its volume. Compression of hydrogen gas naturally increases its temperature, due to Charles' Law.
Hydrogen compressors are closely related to hydrogen pumps and gas compressor
Gas compressor
A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume.Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe. As gases are compressible, the compressor also reduces the volume of a gas...
s: both increase the pressure on a fluid
Fluid
In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids....
and both can transport the fluid through a pipe
Hydrogen piping
Hydrogen piping, in industrial settings, is a system of pipes used to move hydrogen. Due to issues with hydrogen embrittlement, and corrosion, materials for hydrogen pipes must be carefully selected...
. As gases are compressible, the compressor also reduces the volume of hydrogen gas, whereas the main result of a pump raising the pressure of a liquid
Liquid
Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...
is to allow the liquid hydrogen
Liquid hydrogen
Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...
to be transported elsewhere.
Piston-Metal Diaphragm compressor
PistonPiston
A piston is a component of reciprocating engines, reciprocating pumps, gas compressors and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tight by piston rings. In an engine, its purpose is to transfer force from...
-metal diaphragm compressor
Diaphragm compressor
A diaphragm compressor is a variant of the classic reciprocating compressor with backup and piston rings and rod seal. The compression of gas occurs by means of a flexible membrane, instead of an intake element. The back and forth moving membrane is driven by a rod and a crankshaft mechanism. Only...
s are stationary high-pressure compressors, 4-staged water-cooled, 11~15 kW 30~50Nm3/h 40MPa for dispensation of hydrogen. Since compression generates heat, the compressed gas is to be cooled between stages making the compression less adiabatic
Adiabatic process
In thermodynamics, an adiabatic process or an isocaloric process is a thermodynamic process in which the net heat transfer to or from the working fluid is zero. Such a process can occur if the container of the system has thermally-insulated walls or the process happens in an extremely short time,...
and more isothermal. The default assumption on diaphragm hydrogen compressors is an adiabatic efficiency of 70%. Used in hydrogen station
Hydrogen station
A hydrogen station is a storage or filling station for hydrogen, usually located along a road or hydrogen highway, or at home as part of the distributed generation resources concept. The stations are usually intended to power vehicles, but can also be used to power small devices. Vehicles use...
s.
Ionic liquid piston compressor
A ionic liquid piston compressorIonic liquid piston compressor
An ionic liquid piston compressor, ionic compressor or ionic liquid piston pump is a hydrogen compressor based on an ionic liquid piston instead of a metal piston as in a piston-metal diaphragm compressor.-Principle:...
, is a hydrogen compressor based on a ionic liquid
Ionic liquid
An ionic liquid is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below some arbitrary temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of electrically neutral molecules, ILs are largely made...
piston instead of a metal piston as in a piston-metal diaphragm compressor
Diaphragm compressor
A diaphragm compressor is a variant of the classic reciprocating compressor with backup and piston rings and rod seal. The compression of gas occurs by means of a flexible membrane, instead of an intake element. The back and forth moving membrane is driven by a rod and a crankshaft mechanism. Only...
.
Guided rotor compressor
The guided rotor compressorGuided rotor compressor
The guided rotor compressor is a positive displacement rotary gas compressor. The compression volume is defined by the trochoidally rotating rotor mounted on an eccentric drive shaft with a typical 80 to 85% adiabatic efficiency.-History:...
(GRC) is a positive displacement rotary compressor
Gas compressor
A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume.Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe. As gases are compressible, the compressor also reduces the volume of a gas...
based upon an envoluted trochoid geometry which utilizes a parallel trochoid
Trochoid
thumb|290px|right|A [[cycloid]] generated by a rolling circleTrochoid is the word created by Gilles de Roberval for the curve described by a fixed point as a circle rolls along a straight line...
curve to define its basic compression volume. It has a typical 80 to 85% adiabatic efficiency.
Linear compressor
The single piston linear compressorLinear compressor
A linear compressor is a gas compressor where the piston moves along a linear track to compress to minimize energy loss during conversion.-History:...
uses dynamic counterbalancing, where an auxiliary movable mass is flexibly attached to a movable piston assembly and to the stationary compressor casing using auxiliary mechanical springs with zero vibration export at minimum electrical power and current consumed by the motor. It is used in cryogenics
Hydride compressor
In a hydride compressorHydride compressor
A hydride compressor is a hydrogen compressor based on metal hydrides with absorption of hydrogen at low pressure and desorption of hydrogen at high pressure by raising the temperature with an external heat source like a heated waterbed or electric coil....
, thermal and pressure properties of a hydride
Hydride
In chemistry, a hydride is the anion of hydrogen, H−, or, more commonly, a compound in which one or more hydrogen centres have nucleophilic, reducing, or basic properties. In compounds that are regarded as hydrides, hydrogen is bonded to a more electropositive element or group...
are used to absorb low pressure hydrogen gas at ambient temperatures and then release high pressure hydrogen gas at higher temperatures; the bed of hydride is heated with hot water or an electric coil.
Electrochemical hydrogen compressor
A multi-stage electrochemical hydrogen compressorElectrochemical hydrogen compressor
An electrochemical hydrogen compressor is a hydrogen compressor where hydrogen is supplied to the anode, and compressed hydrogen is collected at the cathode with an exergy efficiency of 70 to 80% for pressures up to 10,000 psi or 700 bars.-Principle:...
incorporates a series of membrane-electrode-assemblies
Membrane electrode assembly
A membrane electrode assembly is an assembled stack of proton exchange membranes or alkali anion exchange membrane , catalyst and flat plate electrode used in a fuel cell.-PEM-MEA:...
(MEAs), similar to those used in proton exchange membrane fuel cell
Proton exchange membrane fuel cell
Proton exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells , are a type of fuel cell being developed for transport applications as well as for stationary fuel cell applications and portable fuel cell applications. Their distinguishing features include lower...
s, this type of compressor has no moving parts and is compact. With electrochemical compression of hydrogen a pressure of 5000 psi is achieved. Pressure is believed to go beyond 10,000 psi to the structural limits of the design. A patent is pending for an exergy efficiency
Exergy efficiency
Exergy efficiency computes the efficiency of a process taking the second law of thermodynamics into account.-Motivation:...
of 70 to 80% for pressures up to 10,000 psi or 700 bars
See also
- Compressed hydrogenCompressed hydrogenCompressed hydrogen is the gaseous state of the element hydrogen kept under pressure. Compressed hydrogen in hydrogen tanks at 350 bar and 700 bar is used for mobile hydrogen storage in hydrogen vehicles...
- Hydrogen turboexpander-generatorHydrogen turboexpander-generatorA hydrogen turboexpander-generator or generator loaded expander for hydrogen gas is an axial flow turbine or radial expander for energy recovery through which a high pressure hydrogen gas is expanded to produce work that is used to drive a electrical generator...
- High pressure electrolysisHigh pressure electrolysisHigh-pressure electrolysis is the electrolysis of water by decomposition of water into oxygen and hydrogen gas due to the passing of an electric current through the water. The difference with a standard proton exchange membrane electrolyzer is the compressed hydrogen output around 120–200 Bar ...
- Hydrogen embrittlementHydrogen embrittlementHydrogen embrittlement is the process by which various metals, most importantly high-strength steel, become brittle and fracture following exposure to hydrogen...
- Hydrogen tankHydrogen tankA Hydrogen tank is used for hydrogen storage. The first type IV hydrogen tanks for compressed hydrogen at 700 Bar were demonstrated in 2001, the first fuel cell vehicles on the road with type IV tanks are the Toyota FCHV, Mercedes-Benz F-Cell and the HydroGen4.At the hydrogen station Hamburg...
- Hydrogen leak testingHydrogen leak testingHydrogen leak testing is the normal way in which a hydrogen pressure vessel or installation is checked for leaks or flaws. There are various tests....