A steam generator for a fuel cell system having a heat exchanger (34) with at least one internal heat exchange surface, a water inflow pipe (46), a dripper head (52) with a flow passageway fluidly connected to the water inflow pipe (46). The dripper head (52) extends inside the heat exchanger (52) above the heat exchange surface for feeding water down onto the heat exchange surface for conversion into steam. The dripper head (52) has outlet holes (56) spaced along the flow passageway and between adjacent outlet (holes 56) the dripper head has a stepped profile on at least its underside to prevent droplets from adjacent holes coalescing. A fuel inflow pipe can have a section mounted coaxially to a part of the water inflow pipe (46). The fuel inflow pipe's section can surround the water inflow pipe's part. In a fuel cell system with a steam generator, the steam generator can include the fuel inflow pipe and a combined steam and fuel outlet and a reformer directly or indirectly connected downstream of the steam generator.

In the method for conversion with recovery of energy carriers in a cyclical process of a thermal engine, a first recirculation cycle is formed involving gas generator, device for converting kinetic and thermal energy into mechanical energy, hydrogenation reactor, and gas generator. Water is evaporated in steam boilers, and steam is fed into turbine for converting steam energy into mechanical energy. In this process, steam boilers are located in gas generator and in hydrogenation reactor. The steam is carried onward from conversion device into condenser, and a second recirculation cycle is formed. Atmospheric oxygen from an air bubble is supplied to gas generator. The air is cooled, and cooling operation is repeated, until a maximum residual water content in the air of 0.2 g/m3 is attained. Formed condensate is collected and used steam boilers. Invention makes it possible to simplify process of recovering carbon oxides formed in thermal engines.

In the method for conversion with recovery of energy carriers in a cyclical process of a thermal engine, a first recirculation cycle is formed involving gas generator, device for converting kinetic and thermal energy into mechanical energy, hydrogenation reactor, and gas generator. Water is evaporated in steam boilers, and steam is fed into turbine for converting steam energy into mechanical energy. In this process, steam boilers are located in gas generator and in hydrogenation reactor. The steam is carried onward from conversion device into condenser, and a second recirculation cycle is formed. Atmospheric oxygen from an air bubble is supplied to gas generator. The air is cooled, and cooling operation is repeated, until a maximum residual water content in the air of 0.2 g/m3 is attained. Formed condensate is collected and used steam boilers. Invention makes it possible to simplify process of recovering carbon oxides formed in thermal engines.

A vaporizer apparatus for vaporizing liquefied natural gas (LNG) into vapor-phase natural gas for injection into an oil or gas well, comprises a blower assembly, a burner section, a heat exchanger section, and at least one flammable gas concentration sensor. The blower assembly comprises a primary blower configured to move air along an air flow path through the vaporizer apparatus and a flame arrestor configured to allow passage of the air into the vaporizer apparatus and impede passage of a flame out of the vaporizer apparatus. The burner section comprises an enclosure having an upstream end coupled to the blower assembly and a downstream end, and a burner inside the enclosure and in the air flow path for heating the air. The heat exchanger section comprises an enclosure having an upstream end coupled to the downstream end of the burner section enclosure and a downstream end, and at least one LNG heat exchange tube inside the enclosure and in the air flow path, and thermally communicable with the air heated by the burner. The at least one flammable gas concentration sensor is in the air flow path upstream of the burner and is configured to detect whether a concentration of a flammable gas in the air is above a flammable gas concentration set point.

A novel two-chamber design for thermal boilers is presented in this document. The boiler uses spiral-shaped tubes with conical and flat portions which form a combustion chamber. The use of a direct flame burner causes exhaust gas turbulence and increases the gas pressure in the main chamber. The high-pressure gases, which have lost their kinetic energy due to collision with spirals, leave the main chamber and enter into the secondary chamber, where their energy is used to preheat inlet water. The control of distance between spirals, the reverse flow of exhaust gases in the chambers, and the specific geometry of the spirals maximize boiler efficiency,

A multi-circulation heat recovery steam generator (HRSG) for steam assisted gravity drainage (SAGD)/Enhanced Oil Recovery (EOR) processes comprises a steam drum internally partitioned to provide a clean side and a dirty side. The clean side downcomer pipe supplies water to one or more generating banks as part of a clean circuit located in a high heat flux zone of the boiler. Boiler water is fed from the clean side of the drum to the dirty side of the drum via natural head differential. Water is then fed through a corresponding downcomer to a dirty generating bank, which is located in a low heat flux zone of the boiler.

The present invention provides a device which comprises: a heat exchanger (1) for transferring heat of a heat-supplying medium to a working medium which differs from said heat-supplying medium, a first supply device designed to provide a flow of the heat-supplying medium at a first temperature from a heat source to the heat exchanger, and a second supply device which is designed to deliver the heat-supplying medium after it has passed through the heat exchanger, and/or a further medium at a second temperature lower than the first temperature, to the flow of the heat-supplying medium at the first temperature.

The present invention provides a device which comprises: a heat exchanger (1) for transferring heat of a heat-supplying medium to a working medium which differs from said heat-supplying medium, a first supply device designed to provide a flow of the heat-supplying medium at a first temperature from a heat source to the heat exchanger, and a second supply device which is designed to deliver the heat-supplying medium after it has passed through the heat exchanger, and/or a further medium at a second temperature lower than the first temperature, to the flow of the heat-supplying medium at the first temperature.

Method for operating an arrangement for using waste heat of an internal combustion engine, wherein the internal combustion engine has an exhaust gas duct and the arrangement for using waste heat has a circuit conveying a working medium. In the circuit are arranged, in the flow direction of the working medium, a pump, at least one evaporator, an expansion machine and a condenser. The at least one evaporator is also arranged in the exhaust gas duct, wherein in the at least one evaporator an exhaust gas expelled from the internal combustion engine is used as a heat source, and thus the working medium is evaporated in the evaporator. The method according to the invention detects, inside the at least one evaporator, a leakage of the working medium into the exhaust gas duct.

A process for reducing pressure of a vapor stream used for reducing a temperature or pressure in a reactor. A pressure of a vapor stream is reduced with a turbine to provide a lower pressure vapor stream. The vapor stream rotates a turbine wheel within the turbine. The turbine wheel is configured to transmit rotational movement to an electrical generator. Thus, electricity is generated with the turbine. The lower pressure vapor stream is injected into a reactor and reduces a temperature in the reactor or reduces a partial pressure of a hydrocarbon vapor in the reactor.