A high temperature fuel cell stack system, such as a solid oxide fuel cell system, with an improved balance of plant efficiency includes a thermally integrated reformer, combustor and the fuel cell stack.

High temperature fuel cell system and method of operating same

A thermally integrated reformer (10) is located inside the stack furnace (12) housing stacks (14) of solid oxide fuel cells (16). The energy to support the endothermic reformation reaction converting hydrocarbon and water feedstock into hydrogen and carbon monoxide fuel is supplied by heat recovered from the oxidation process in the stack (14) of fuel cells (16). The source of hydrocarbons is desulfurized natural gas. Heat transfers to reformers (10) which may be incrementally shielded packed beds (30, 60) of the reactors (18, 19) of the reformer (10) by radiation from the stacks (14), furnace wall (38), or both and by forced convection from the exhausting airflow exiting the stack furnace (12). Temperature gradients in the reformer (10) may be controlled by selective (or incremented) radiation shielding (20) and by counterflow heat exchange to prevent excessive premature cracking in the reformer. Such an optimized design uses a minimum amount of catalyst, yet prevents carbonization from clogging interstices or otherwise rendering the catalyst or catalyst granules (32) ineffective. Alternatively sufficient catalyst may be provided to render the reformation process a heat-limited reaction. In this circumstance, the stacks (132) configured in a module (106) may transfer heat directly to a reformer (110) surrounding the module (106). The air may pass through a heat exchanger 108 or preheater (200) positioned proximate the module 106 in an insulated enclosure (102).

Integrated reformer/cpn sofc stack module design

An integrated fuel cell unit (10) includes an annular array (12) of fuel cell stacks (14), an annular cathode recuperator (20), an annular anode recuperator (22), a reformer (24), and an anode exhaust cooler (26), all integrated within a common housing structure (28).

Integrated solid oxide fuel cell and fuel processor

A power supply includes a fuel cell stack (58), a thermoelectric module (40) and a burner module (34). The fuel cell stack generates a primary source of electricity and secondary source of heat. The thermoelectric module generates a secondary source of electricity. The burner module is juxtaposed to the fuel cell stack and the thermoelectric module, to provide primary heat to the system and to generate a temperature differential across the thermoelectric module, and to pre-heat a fuel and an oxidant for the fuel cell stack. The burner module is regulated to maintain a given system temperature, or when needed by the thermoelectric generator for secondary power generation.

Hybrid self-contained heating and electrical power supply incorporating a hydrogen fuel cell, a thermoelectric generator and a catalytic burner

Various hot box fuel cell system components are provided, such as heat exchangers, steam generator and other components.

Sofc hot box components

A process and device for converting chemical energy from a fuel into thermal and at the same time directly into electrical energy, in which the primary fuel flow (1) is divided into at least two parallel and separately regulated (4; 5) partial flows (2; 3) taken to a fuel cell (6) and a burner (7) and the oxygen vehicle flow (8) is regulated either in its entirety or in partial flows (12; 13) in such a way that the electrical and thermal energy flows are fully decoupled. The partial flow (12) of the oxygen vehicle intended for the high-temperature fuel cell (6) is preheated (14) by the entire exhaust gas current (25). The latter's thermal energy is used to prepare the primary fuel by evaporation (27) and conversion (26) and to provide useful heat (18; 19). A compact, integrated construction with a container (20) containing the fuel cell (6), the burner (7), the after-burner (28) and the converter (26) in the central section and the heat exchanger, lines, controls and accessories in the peripheral section.

Process and device for converting chemical energy from a fuel into thermal energy and, at the same time, directly into electrical energy

Verfahren und Vorrichtung zur Umwandlung von chemischer Energie eines Brennstoffs in thermische und gleichzeitig direkt in elektrische Energie, wobei der Primarbrennstoffstrom (1) in mindestens zwei parallel geschaltete, separat regulierte (4; 5), je einer Brennstoffzelle (6) und einem Brenner (7) zugefuhrte Teilstrome (2; 3) aufgeteilt wird und der Sauerstofftragerstrom (8) entweder als Ganzes oder in Teilstrome (12; 13) aufgeteilt reguliert (10; 11) wird, dergestalt, dass vollige Entkoppelung zwischen elektrischem und thermischem Energiestroms erzielt wird. Der fur die Hochtemperatur-Brennstoffzelle (6) bestimmte Teilstrom (12) des Sauerstofftragers wird vom Gesamt-Abgasstrom (25) vorgewarmt (14). Die thermische Energie des letzteren wird zur Aufbereitung des Primarbrennstoffs durch Verdampfung (27) und Konvertierung (26) und zur Nutzwarmebereitstellung (18; 19) verwendet. Kompakte, integrierte Bauweise mit Behalter (20), enthaltend im zentralen Teil Brennstoffzelle (6), Brenner (7), Nachbrenner (28), Konverter (26), im peripheren Teil Warmeaustauscher, Leitungen, Steuerorgane und Zubehor.

Ulf Dr. Bossel

Papers

Process and device for converting chemical energy from a fuel into thermal energy and, at the same time, directly into electrical energy

Verfahren und vorrichtung zur umwandlung von chemischer energie eines brennstoffs in thermische energie und gleichzeitig direkt in elektrische energie