A hydrogen compressor is a device that increases the pressure of hydrogen by reducing its volume resulting in compressed hydrogen or liquid hydrogen.
Traditionally, applications for hydrogen compressors included Chlorine electrolyser and many chemical applications like the production of hydrogen peroxide (HPPO). The newer applications related to green and environmentally friendly technologies include fuel cells and electrolysis for hydrogen production. [1]
Hydrogen compressors are closely related to hydrogen pumps and gas compressors: 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.
A proven method to compress hydrogen is to apply reciprocating piston compressors. Widely used in refineries, they are the backbone of refining crude oil. Reciprocating piston compressors are commonly available as either oil-lubricated or non-lubricated; for high pressure (350 - 700 bar), non-lubricated compressors are preferred to avoid oil contamination of the hydrogen. Typical drive power is in the order of magnitude of Megawatts (300kW-15MW). Expert know-how on piston sealing and packing rings can ensure that reciprocating compressors outperform the competing technologies in terms of MTBO (Mean Time Between Overhaul).
An ionic liquid piston compressor is a hydrogen compressor based on an ionic liquid piston instead of a metal piston as in a piston-metal diaphragm compressor. [2]
A multi-stage electrochemical hydrogen compressor incorporates a series of membrane-electrode-assemblies (MEAs), similar to those used in proton-exchange membrane fuel cells; this type of compressor has no moving parts and is compact. The electrochemical compressor works similar to a fuel cell, a voltage is applied to the membrane and the resulting electric current pulls hydrogen through the membrane. With electrochemical compression of hydrogen, a pressure of 14500 psi (1000bar or 100MPa) is achieved. A patent is pending claiming an exergy efficiency of 70 to 80% for pressures up to 10,000 psi or 700 bars. [3] A single stage electrochemical compression to 800 bar was reported in 2011. [4]
In a hydride compressor, 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. [5]
Piston-metal diaphragm compressors are stationary high-pressure compressors, four-staged water-cooled, 11–15 kW, 30–50 Nm3/h 40 MPa for dispensation of hydrogen. [6] 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%. [7] Used in hydrogen stations.
The guided rotor compressor (GRC) is a positive-displacement rotary compressor based upon an envoluted[ check spelling ] trochoid geometry which utilizes a parallel trochoid curve to define its basic compression volume. [8] [9] It has a typical 80 to 85% adiabatic efficiency. [10]
The single-piston linear compressor 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. [11] It is used in cryogenics
2023 saw the invention of a compressor cylinder which heats gas to multiply it's pressure. There is no pressure limit as any start pressure is multiplied. First public mention is in Patent Application No. PCT/AU2023/051351.
A pump is a device that moves fluids, or sometimes slurries, by mechanical action, typically converted from electrical energy into hydraulic energy.
An air compressor is a machine that takes ambient air from the surroundings and discharges it at a higher pressure. It is an application of a gas compressor and a pneumatic device that converts mechanical power into potential energy stored in compressed air, which has many uses. A common application is to compress air into a storage tank, for immediate or later use. When the delivery pressure reaches its set upper limit, the compressor is shut off, or the excess air is released through an overpressure valve. The compressed air is stored in the tank until it is needed. The pressure energy provided by the compressed air can be used for a variety of applications such as pneumatic tools as it is released. When tank pressure reaches its lower limit, the air compressor turns on again and re-pressurizes the tank. A compressor is different from a pump because it works on a gas, while pumps work on a liquid.
The Brayton cycle, also known as the Joule cycle, is a thermodynamic cycle that describes the operation of certain heat engines that have air or some other gas as their working fluid. It is characterized by isentropic compression and expansion, and isobaric heat addition and rejection, though practical engines have adiabatic rather than isentropic steps.
Compressed-air energy storage (CAES) is a way to store energy for later use using compressed air. At a utility scale, energy generated during periods of low demand can be released during peak load periods.
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
A diving air compressor is a breathing air compressor that can provide breathing air directly to a surface-supplied diver, or fill diving cylinders with high-pressure air pure enough to be used as a hyperbaric breathing gas. A low pressure diving air compressor usually has a delivery pressure of up to 30 bar, which is regulated to suit the depth of the dive. A high pressure diving compressor has a delivery pressure which is usually over 150 bar, and is commonly between 200 and 300 bar. The pressure is limited by an overpressure valve which may be adjustable.
A reciprocating compressor or piston compressor is a positive-displacement compressor that uses pistons driven by a crankshaft to deliver gases at high pressure. Pressures of up to 5,000 PSIG are commonly produced by multistage reciprocating compressors.
Vapour-compression refrigeration or vapor-compression refrigeration system (VCRS), in which the refrigerant undergoes phase changes, is one of the many refrigeration cycles and is the most widely used method for air conditioning of buildings and automobiles. It is also used in domestic and commercial refrigerators, large-scale warehouses for chilled or frozen storage of foods and meats, refrigerated trucks and railroad cars, and a host of other commercial and industrial services. Oil refineries, petrochemical and chemical processing plants, and natural gas processing plants are among the many types of industrial plants that often utilize large vapor-compression refrigeration systems. Cascade refrigeration systems may also be implemented using two compressors.
A turboexpander, also referred to as a turbo-expander or an expansion turbine, is a centrifugal or axial-flow turbine, through which a high-pressure gas is expanded to produce work that is often used to drive a compressor or generator.
Hydrogen technologies are technologies that relate to the production and use of hydrogen as a part hydrogen economy. Hydrogen technologies are applicable for many uses.
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 the membrane and the compressor box come in touch with pumped gas. For this reason this construction is the best suited for pumping toxic and explosive gases. The membrane has to be reliable enough to take the strain of pumped gas. It must also have adequate chemical properties and sufficient temperature resistance.
Chlorine gas can be produced by extracting from natural materials, including the electrolysis of a sodium chloride solution (brine) and other ways.
High-pressure electrolysis (HPE) is the electrolysis of water by decomposition of water (H2O) into oxygen (O2) and hydrogen gas (H2) 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 12–20 megapascals (120–200 bar) at 70 °C. By pressurising the hydrogen in the electrolyser the need for an external hydrogen compressor is eliminated, the average energy consumption for internal differential pressure compression is around 3%.
The guided-rotor compressor (GRC) 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.
A hydride compressor is a hydrogen compressor based on metal hydrides with absorption of hydrogen at low pressure, releasing heat, and desorption of hydrogen at high pressure, absorbing heat, by raising the temperature with an external heat source like a heated waterbed or electric coil.
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 up to and even beyond 80% for pressures up to 10,000 psi or 700 bars.
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.
A Johnson thermoelectric energy converter or JTEC is a type of solid-state heat engine that uses the electrochemical oxidation and reduction of hydrogen in a two-cell, thermal cycle that approximates the Ericsson cycle. It is under investigation as a viable alternative to conventional thermoelectric conversion. Lonnie Johnson invented it and claims the converter exhibits an energy conversion efficiency of as much as 60%, however, this claim is at a theoretical level based on comparison with a Carnot cycle and assumes a temperature gradient of 600 °C. It was originally proposed for funding to the Office of Naval Research but was refused. Johnson obtained later funding by framing the engine as a hydrogen fuel cell. Johnson had been collaborating with PARC on development of the engine.
Proton exchange membrane(PEM) electrolysis is the electrolysis of water in a cell equipped with a solid polymer electrolyte (SPE) that is responsible for the conduction of protons, separation of product gases, and electrical insulation of the electrodes. The PEM electrolyzer was introduced to overcome the issues of partial load, low current density, and low pressure operation currently plaguing the alkaline electrolyzer. It involves a proton-exchange membrane.
An internal combustion engine is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to.