RU2580738C1 - Reactor for producing synthesis gas - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to chemical industry, namely to catalytic reactor for producing synthesis gas, which can be used as initiating hydrogen additives to main fuel in internal combustion engines and gas turbine engines. Reactor comprises mixing-distributing starter, tangential inlet, spark plug, one or several catalytic units and borehole heat exchanger, before first catalytic unit there is porous screen, at outlet of gas flow from last catalytic unit is element of high-temperature heat insulation, on side surface of catalytic unit there is layer of high-temperature heat insulation, separated from cooling heat exchanger with annular gap, reactor is made in form of single device without detachable connections.

EFFECT: invention provides high efficiency of converting natural gas to synthesis gas, reduced heat losses and increasing service life of device operation and safety.

2 cl, 2 dwg

Description

The invention relates to the field of chemical engineering, to a catalytic reactor for producing synthesis gas, and in particular to a device for carrying out the catalytic partial oxidation of natural gas, and can be used to produce synthesis gas for the purpose of its use as initiating hydrogen additives to the main fuel in internal combustion engines and in gas turbine engines.

Known catalytic reactor (RU 2208475, B01J 8/04; C01B 3/00, 07/20/2003) for producing radial type synthesis gas containing a gas distribution pipe with a catalyst layer, which is made in the form of gas-permeable flat and corrugated reinforced tapes, wound and sintered with a gas distribution pipe with gaps between the turns with the formation of gas-air channels between the tapes. The reactor has a heating device to put it into operation. The gas distribution pipe has perforation holes with a diameter smaller than the critical diameter to prevent flame from entering the gas distribution pipe. As a catalyst, a reinforced porous material containing active components is used: rhodium, nickel, platinum, palladium, iron, cobalt, rhenium, ruthenium, or a mixture thereof.

The disadvantage of this device is the high complexity of the manufacture of reinforced porous materials, a decrease in the total catalytic activity due to the use of reinforcing materials, and the high temperature of the synthesis gas leaving the reactor.

A device for generating synthesis gas (RU 2446092, C01B 3/38, B01J 8/04, 06/25/2010) is known, which comprises a mixing and distribution starting device, a tangential input, a spark plug or an electric heating element, one or more catalytic units and submersible heat exchanger of the corridor type.

The catalytic block is made in the form of axial blocks of alternating flat and corrugated heat-conducting metal-porous catalytic tapes with channels for the passage of gas flows. The submersible heat exchanger is heat integrated with the catalytic reactor.

The above device is the closest in technical essence to the claimed device and therefore is selected as a prototype.

A disadvantage of the known device is its low resource due to overheating of the ignition mixture ignition device included in it during operation and a possible loss of tightness of the detachable flange connection of the mixing and distribution starting device with a cylindrical cooled body during operation of the reactor.

The problem solved by the invention is the creation of a compact reactor with increased efficiency, a long service life and low labor intensity.

The technical result from the use of the invention is to increase the efficiency of conversion of natural gas to synthesis gas by reducing heat loss and inclusion in the overall engine cooling system, increasing the service life, safety.

This result is achieved by the fact that in the reactor for producing synthesis gas containing a mixing and distribution starting device with a tangential input, a spark plug, one or more catalytic units and an immersion heat exchanger, a porous screen is placed in front of the first catalytic unit, at the outlet of the gas stream from the last the catalytic block is an element of high temperature insulation, while on the side surface of the catalytic block is a layer of high temperature insulation, lenny by immersion exchanger annular gap, and the catalyst unit is made of porous material, wherein the reactor is designed as a single, integrated device without heat for detachable connections.

In the starting device there is a reactor starting system with a vortex-type gas burner, consisting of a conical distributor with a flame stabilizer and containing a cooled spark plug.

The above and other aspects and advantages of the present invention are disclosed in the following detailed description thereof, given with reference to the drawings, in which: 1 - presents the design of the inventive reactor, a cross section; in FIG. 2 is a transverse section along the plane AA.

The synthesis gas reactor (Fig. 1) contains a sealed cylindrical cooled case with the following located in it: a mixing and distribution starting device 1 with a tangential input of working reagents 2, a spark plug 3, one or more catalytic units 4, a heat exchanger 5 for heating working reagents, immersion heat exchanger 6 to reduce the temperature of the spark plug 3 and reduce the temperature of the synthesis gas. To control and regulate the reactor operating modes, at least three thermocouples have been introduced in its design; a thermocouple 7 in the front (frontal) catalyst bed, a thermocouple 8 at the outlet of the catalytic unit 4, a thermocouple 9, in a heat carrier (antifreeze) at the outlet of the submersible heat exchanger 6. A porous screen 10 is installed in front of the catalytic unit 4. At the exit of the catalytic unit 4, at some distance there is an element of high-temperature thermal insulation 11. On the side surface of the catalytic block 4 there is a layer of high-temperature thermal insulation 12, separated from the immersion heat exchanger 6 with a gap 13. To ensure a stable start Single trigger introduced into stabilizing element 14 in the form of a plate perpendicularly installed in an amount not less than 3 to porous screen 10.

In the design of the reactor there are nozzles for introducing natural gas 15, for introducing air 16, for entering coolant 17, as well as nozzles for removing coolant 18 and synthesis gas 19.

The device operates as follows.

When starting up the reactor, working reagents: natural gas and air are supplied through nozzles 15 and 16 to the mixing and distribution starting device 1 with an excess air coefficient of 1.0 ÷ 1.2. In the starter housing 1, the working reagents supplied with a tangential swirl through the tangential inlet 2 are mixed until they are homogeneous, stabilized on the stabilization element 14, which is a set of plates mounted perpendicular to the porous screen 10. A stabilized gas stream is supplied into the zone by spark plug 3, where the mixture lights up. The combustion products heat the catalytic unit 4 before the start of the partial oxidation reaction (450-600 ° C). According to a thermocouple 7 installed in the zone of the frontal layer of the catalyst, when the temperature reaches 450-600 ° C, the reactor control system (not shown in Fig.) Changes the composition of the gas reagents at the inlet to the reactor to an excess air coefficient in the range 0.26-0.32 . The partial oxidation of natural gas occurs at a working temperature of 750-950 ° C on the heated catalyst of the catalytic unit 4 at a given coefficient of excess air. In the submersible heat exchanger 6, due to the coolant supplied through the nozzle 17, the temperature of the synthesis gas decreases to 100 ÷ 150 ° C and the synthesis gas is fed through the nozzle 19 into the engine combustion chamber, and the coolant through the nozzle 18 enters the cooling system of the internal combustion engine . Upon reaching the operating mode of the internal combustion engine, part of the exhaust gases of the engine can be supplied to the reactor together with the natural gas-air mixture through the pipe 15, providing a mixed air-carbon-dioxide conversion mode. The heat exchanger 5 provides a preliminary heating of the working gases entering the reactor through the nozzles 15 and 16. In this case, the heat in the heat exchanger 5 during operation of the reactor comes from the side of the catalytic unit 4, heated to high temperatures. At the same time, the submersible heat exchanger 6 performs several functions: it reduces the working temperature of the synthesis gas in order to increase the filling capacity of the cylinders of internal combustion engines and to eliminate the reduction in power, to ensure safety when installing on a vehicle. When using liquid from the cooling system of an internal combustion engine as a cooler, an additional function appears for starting an internal combustion engine in the cold season, because during engine start-up, the coolant will be warmed up, and warm synthesis gas will enter the combustion chamber of the engine. The gap 13 allows the passage of hot synthesis gas from the catalytic unit 4 to the immersion heat exchanger 6 along the layer of high temperature insulation 12. The presence of hot synthesis gas in the gap 13 reduces the heat flux from the high temperature insulation 12 to the side of the immersion heat exchanger 6, which reduces the heat loss of the catalytic unit 4 and increases the efficiency of the reactor. The stabilization element 14 provides a stable ignition of the gas mixture when starting the reactor. One or more catalytic units arranged in series can be used in a reactor. To reduce heat loss, a porous screen 10 is installed in front of the catalytic unit 4, and an element of high-temperature thermal insulation 11 is placed at the outlet of the catalytic unit 4.

The reactor can be manufactured as follows.

In the manufacture of a reactor for the production of synthesis gas, domestic materials can be used. The mixing and distribution starting device is made in the form of a truncated cone with the tangential introduction of gas reagents, while in the starting mode the device serves as a gas burner with electric ignition, and in the synthesis gas generation mode, as a distribution device.

The catalytic unit 4 is a domestic development made of an alloy based on nickel. The reactor components - spark plug 3, high-temperature thermocouples 7, 8 and low-temperature thermocouple 9, raw materials for high-temperature thermal insulation 11, 12 are serial domestic products that are present on the domestic market. The porous screen 10 can be made of 12X18H10T stainless steel mesh. All other reactor components can also be made of 12X18H10T stainless steel by bending, turning and milling, and argon-arc welding in a typical mechanical section.

A prototype reactor was made, which was tested in real conditions on a Barguzin automobile and worked out more than 1000 operating hours. At the same time, it showed high work efficiency: the proposed device allows you to convert fuel (natural gas) into hydrogen-containing synthesis gas. In the partial oxidation mode, the hydrogen content in the synthesis gas is up to 33%.

The design of the proposed reactor due to improvements allows you to create a compact reactor with good dynamic and resource characteristics. The reactor can be used both in the partial oxidation of fuel mode and in the mixed air-carbon-dioxide conversion mode, which is very important when used in conjunction with internal combustion engines. Using the mixed conversion mode allows to reduce the operating temperature of the reactor and, accordingly, increase the resource, as well as reduce the risk of soot precipitation during transient conditions and increase the hydrogen content in the synthesis gas through the use of oxidizing agents in the form of water vapor and carbon dioxide.

Claims (2)

1. A reactor for producing synthesis gas, comprising a mixing distributor starting device, a tangential input, a spark plug, one or more catalytic units and an immersion heat exchanger, characterized in that a porous screen is placed in front of the first catalytic unit at the outlet of the gas stream from the latter the catalytic unit is an element of high-temperature thermal insulation, while on the side surface of the catalytic unit is a layer of high-temperature thermal insulation, separated from the cooling heat exchanger annular gap, and the reactor is made in the form of a single device. 2. The reactor according to claim 1, characterized in that in the starting device there is a reactor starting system with a vortex-type gas burner, consisting of a conical distributor with a flame stabilizer and containing a cooled spark plug.

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