A furnace for performing an endothermic process comprising tubes containing a catalyst for converting a gaseous feed, wherein tubes are positioned in rows inside the furnace, wherein burners are mounted between the tubes and between the tubes and the furnace walls parallel to the tubes row and wherein the burners rows and the tubes rows are ended by end walls and are divided into sections with the distance from the end burner to the end wall being B2W, the distance between two adjacent burners in the section being B2B, and half the distance in-between two sections being B2S, wherein the burners in the rows are arranged in such a way that the ratios B2B/B2W and B2B/B2S are greater than 1.3 thus limiting the occurrence of the flame merging phenomenon and reducing significantly the quadratic mean of the tube temperature profile.

A system includes a tank containing a fluid to be heated; a U-shaped pipe disposed proximate a bottom of the tank, a majority of the extent of the U-shaped pipe being disposed within an interior of the tank; a catalyst unit embedded within the U-shaped pipe, the catalyst unit comprising a catalyst wrapped, natural gas filled, perforated pipe that is configured to enable a catalytic reaction on its exterior; a vent pipe attached to the U-bend pipe which allows air to circulate; and mechanical controls disposed proximate the U-shaped pipe configured to vary temperature output.

A system includes a tank containing a fluid to be heated; a U-shaped pipe disposed proximate a bottom of the tank, a majority of the extent of the U-shaped pipe being disposed within an interior of the tank; a catalyst unit embedded within the U-shaped pipe, the catalyst unit comprising a catalyst wrapped, natural gas filled, perforated pipe that is configured to enable a catalytic reaction on its exterior; a vent pipe attached to the U-bend pipe which allows air to circulate; and mechanical controls disposed proximate the U-shaped pipe configured to vary temperature output.

A process for reducing the CO.sub.2 and other pollutants produced by the combustion of a fuel in a combustion chamber while maintaining or increasing the efficiency of said combustion includes feeding to the combustion chamber, or preconditioning the combustion chamber, with a catalyst, preferably a lithium based salt. Monitoring the energy output and components of the exhaust gas stream to maintain optimum operation allows reduction, during the process, of the catalyst delivery and feed air. The presence of the catalyst results in increased efficiency of operation and reduction of pollutants generated.

A process for reducing the CO.sub.2 and other pollutants produced by the combustion of a fuel in a combustion chamber while maintaining or increasing the efficiency of said combustion includes feeding to the combustion chamber, or preconditioning the combustion chamber, with a catalyst, preferably a lithium based salt. Monitoring the energy output and components of the exhaust gas stream to maintain optimum operation allows reduction, during the process, of the catalyst delivery and feed air. The presence of the catalyst results in increased efficiency of operation and reduction of pollutants generated.

The ignition characteristics of a fuel are adjusted using a unit which has a distribution zone, a oxidation zone and a conversion zone. Fuel is distributed in the distribution zone having a distribution structure. A portion of the fuel is oxidised in the oxidation zone with a oxidising agent on a catalyst on a catalyst carrier, and a portion of the distributed fuel and/or of another supplied fuel is thermally and/or catalytically converted in the conversion zone. The ignition characteristics of the fuel are adjusted via: the molar ratio of oxygen included in the oxidising agent to the oxygen required for the complete oxidation of the fuel provided; and/or via the pressure in the unit; and/or the dwell time; and/or the temperature. Exhaust emissions, in particular NOx and soot emissions, can be lowered.

A gas-fueled portable device for the thermal dispensing of volatile materials such as insect repellents is described. The device employs a pressure regulator to establish gas flow, heat generation, and dispensing temperature at pre-determined optimal values. The automatic operation at pre-determined settings provides simple on/off operation for the user of the device.

A gas-fueled portable device for the thermal dispensing of volatile materials such as insect repellents is described. The device employs a pressure regulator to establish gas flow, heat generation, and dispensing temperature at pre-determined optimal values. The automatic operation at pre-determined settings provides simple on/off operation for the user of the device.

The invention relates to a furnace for performing an endothermic process, the furnace including a plurality of process tubes containing a catalyst for converting a gaseous feed, wherein the process tubes are arranged in rows within the furnace, each row of process tubes thereby defining a process tube row, a plurality of inner burners arranged in rows, each row of inner burners being arranged between and parallel to process tube rows, thereby defining an inner burner row, and a plurality of outer burners arranged in rows, each row of outer burners being arranged between and parallel to a process tube row and a furnace wall, thereby defining an outer burner row. A number of burners of an outer burner row is smaller than a number of burners of an inner burner row. The invention also relates to a process for operating a furnace for performing an endothermic process.

The invention relates to a furnace for performing an endothermic process, the furnace including a plurality of process tubes containing a catalyst for converting a gaseous feed, wherein the process tubes are arranged in rows within the furnace, each row of process tubes thereby defining a process tube row, a plurality of inner burners arranged in rows, each row of inner burners being arranged between and parallel to process tube rows, thereby defining an inner burner row, and a plurality of outer burners arranged in rows, each row of outer burners being arranged between and parallel to a process tube row and a furnace wall, thereby defining an outer burner row. A number of burners of an outer burner row is smaller than a number of burners of an inner burner row. The invention also relates to a process for operating a furnace for performing an endothermic process.