摘要:
Interconnection layouts are described that are particularly effective in the construction of a steam reformer/fuel cell combination for providing domestic heat and/or hot water as well as electricity. A distinguishing feature of the interconnections is that they use strategically placed heat exchangers that permit the operator to optimize the efficiency of operation of the integrated system, and provide a higher efficiency at optimum operation compared to prior art designs. Combinations of reformer/fuel cell systems with conventional furnaces or boilers are also described.
摘要:
The efficiency of a combination reformer/fuel cell system is significantly improved by recapturing the energy value of heat generated in the fuel cell and producing additional power. The cooling water from the fuel cell is mixed, entirely or in part, with sufficient or excess compressed air, and at least partially evaporates in the compressed air. The air is at least sufficient to support the oxidative reactions in the fuel cell and also to serve as oxidant in a burner that provides heat to reform fuel/steam mixtures into hydrogen-containing reformate. This air/steam mixture, after leaving the fuel cell, is further heated by heat exchange with the reformats stream and reformate-producing modules, and with the exhaust stream of the burner. The steam/air mixture is injected into the burner, optionally after superheating in the burner exhaust, and is reacted with fuel in the burner. The burner exhaust may be used to provide heat to a fuel reforming reaction. The high-temperature burner exhaust may also be used to drive an expander, preferably a turbine, at a location in the system which is downstream of the burner, but in which the exhaust is at a high temperature so as to run the turbine efficiently. The turbine recovers heat energy from the fuel cell as mechanical energy, typically in excess of the energy required to run a compressor, because of the addition of steam to the compressed air. Moreover, system heat removal elements, such as radiators, as well as overall system size and cost, can be markedly reduced for a given level of output.
摘要:
According to the present invention, a temperature profile within a preferential oxidation reactor is controlled using a two phase water/steam system to provide a temperature range within the reactor (10) which favors the selective oxidation of CO in a hydrogen rich reformate stream. The reformate is flowed in a mixture with oxygen over a preferential oxidation catalyst (17). The temperature profile is controlled by flowing a stream of water proximate to the preferential oxidation catalyst (17) so as the stream of water and the reformate stream passing over the catalyst (17) are in a heat transfer arrangement. The stream of water is maintained as a two phase stream from a point at which the water reaches its boiling temperature to a point proximate an outlet from which the stream of water exits the reactor (10).
摘要:
A system for making and storing hydrogen comprises an IC engine, a thermal reactor to convert hydrocarbon fuels to reformate, and a separation means to separate the reformate into a hydrogen stream and a hydrogen depleted reformate stream. The hydrogen stream is compressed and stored. The hydrogen depleted reformate stream is split and sent to a thermal reactor and the IC engine. The IC engine drives the compressor for hydrogen as well as the compressor for the fuel inlet to the system. The described system and process achieves high efficiency in fuel conversion and hydrogen storage.
摘要:
High-efficiency combustion engines, including Otto cycle engines, use a steam-diluted fuel charge at elevated pressure. Air is compressed, and water is evaporated into the compressed air via the partial pressure effect using waste heat from the engine. The resultant pressurized air-steam mixture then burned in the engine with fuel, preferably containing hydrogen to maintain flame front propagation. The high-pressure, steam-laden engine exhaust is used to drive an expander to provide additional mechanical power. The exhaust can also be used to reform fuel to provide hydrogen for the engine combustion. The engine advantageously uses the partial pressure effect to convert low-grade waste heat from engine into useful mechanical power. The engine is capable of high efficiencies (e.g. >50%), with minimal emissions.