JPH035304A - Method and device for production of reformed gas containing gaseous hydrogen - Google Patents

Abstract

PURPOSE:To improve the thermal efficiency by recovering the sensible heat of exhaust gas and/or reformed gas and utirizing it to generate steam. CONSTITUTION:The combustion gas 6 generated with a burner 13 is heated through a porous radiation body 2, and then exchanges heat with a process water 10 at an heat exchanger 11 and is discharged as an exhaust gas 7. On the other hand, the radiant heat radiated from a radiation body 2 heats a heat receiving body 4 through a gas-nonpermeable boundary member 5. The raw gas 8 supplied to a tubular reactor 15 from a supply pipe 14 and the steam generated from the process water 10 are passed through a heat receiving body 4 to generate reformed gas 9 containing H2 and CO, which is discharged to the outside of the reacter 15 after having exchanged heat with the process water 10 at a heat exchanger 12.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an apparatus and method for producing reformed gas. More specifically, it is a reformed gas production device that produces a gas mixture containing hydrogen from a raw material gas consisting of water vapor and low-temperature liquefied gas such as LNG or LPG or hydrocarbon gas such as naphtha, methane, or methanol. and on methods.

<Prior Art> Various devices have been proposed in the past for producing reformed gas by heating and reforming raw material gas. On the other hand, as a heating device, there are various devices that use one or two of conduction, convection, and radiation as the main heat transfer methods, taking into account various factors such as the type and condition of the object to be heated or the temperature to be heated. It has been known.

Among these, the heating device disclosed in Japanese Unexamined Patent Publication No. 61-110875 is a radiant heating device mainly employing a radiant heat transfer method.

That is, this radiant heating device has a heating area provided with a porous radiator through a gas-impermeable partition wall, and a heated area provided with a porous heat receiver, and mainly radiates between the two areas. It performs heat exchange by

Also, Proceedings of the 24th Japan Heat Transfer Symposium, 19
May 1987, "Application of heat exchanger using high-performance radiator converter to reactor" and "Advances in chemical engineering series"
, Volume 21 “Combustion and Thermal Engineering” edited by the Chemical Engineering Society, 1987
Porous solid radiation converter (porous radiator)
A method is disclosed for producing a gas mixture containing hydrogen gas by reacting methane and water vapor using a radiant heating device having a radiant heating device.

However, all of these methods and devices only disclose reforming in a high-temperature range that mainly uses direct radiant heat from the heating zone, and do not receive or recover waste heat of combustion exhaust gas or residual heat of reformed gas. There is no disclosure regarding reforming in the low temperature range.

<Problems to be Solved by the Invention> Therefore, an object of the present invention is to provide a reformed gas production apparatus with excellent thermal efficiency.

Another object of the present invention is to provide a radiant heating zone and a heated reforming zone separated by a gas-impermeable boundary member, and to provide for a radiant heating zone and a heated reforming zone separated by a gas impermeable boundary member, and for discharging waste gas from the radiant heating zone and/or reformed gas from the heated reforming zone. An object of the present invention is to provide a reformed gas production device with excellent thermal efficiency, which is equipped with a section for recovering sensible heat and generating steam.

Still another object of the present invention is to provide an apparatus that generates at least a portion of the steam used in the reaction using recovered heat to efficiently produce reformed gas while minimizing energy loss. .

Still another object of the present invention is to provide an industrially advantageous method for producing reformed gas using the above-mentioned reformed gas producing apparatus of the present invention.

Further objects and advantages of the present invention will become apparent from the description below.

<Means for Solving the Problems> and Effects> According to the present invention, the above-mentioned objects and advantages of the present invention are as follows: An apparatus for producing reformed gas containing hydrogen, comprising a radiant heating area and a heated reforming area separated by a gas-impermeable boundary member, the radiant heating area and the radiant heating reforming area being separated by a gas-impermeable boundary member. The radiant heating zones are adjacent to each other while forming independent spaces through the gas impermeable boundary member, and the radiant heating zone is formed in an area adjacent to the gas impermeable boundary member within the radiant heating zone. The heated reforming zone includes a porous radiator through which the heated reformed gas can pass, and the heated reforming zone is heated through the gas-impermeable boundary member by the radiant heat from the porous radiator. It is equipped with a porous heat receiving body that supports a production catalyst and through which raw material gas can pass, and utilizes the sensible heat of the exhaust gas that has passed through the porous radiator on the downstream side of the porous radiator in the radiant heating area. Steam is generated by using the sensible heat of the reformed gas that has passed through the porous heat receiving body in the first heat recovery zone and/or the porous heat receiving body in the heated reforming zone. A second heat recovery zone for producing a reformed gas.

As described above, the reformed gas production device of the present invention includes a first heat recovery zone that recovers sensible heat from exhaust gas and uses it to generate steam; The present invention is intended to advantageously produce reformed gas while increasing heat utilization efficiency.

The reformed gas production apparatus of the present invention preferably includes both first and second heat recovery sections.

To produce a reformed gas by the production apparatus of the present invention, hot gas is formed in the radiant heating zone in an area adjacent to the gas impermeable boundary member and passed through the porous radiator; The porous radiator is heated to a high temperature, a raw material gas consisting of a hydrocarbon gas and steam is introduced into the heated reforming zone upstream of the porous heat receiver, and the porous radiator is heated to a high temperature. A reformed gas is generated by passing through the porous heat receiving body heated by radiant heat emitted from the porous radiator, and the sensible heat of the exhaust gas that has passed through the porous radiator is recovered in a first heat recovery area, and and/or the sensible heat of the reformed gas that has passed through the porous heat receiver is recovered in a second heat recovery zone to produce at least a portion of the steam used in the reaction.

As described above, the reformed gas production apparatus of the present invention includes a radiant heating area and a heated reforming area that are partitioned by a gas-impermeable boundary member.

The gas-impermeable boundary member may be made of a material that is optically transparent to the radiant energy, such as quartz glass, or may be an optically opaque material, such as a metal such as steel.

A porous radiator is present in the radiant heating zone. The porous radiator body can be, for example, a porous metal, a porous metal oxide, a porous ceramic or a porous mineral shaped body.

A hot gas for heating the porous radiator is formed in the radiant heating zone in an area adjacent to the gas-impermeable boundary member and transfers its sensible heat to the porous radiator as it passes through the porous radiator. moving to a radiant body to heat the porous radiant body. The hot gas is produced by combusting the gas from, for example, a gas burner provided in an area adjacent to the gas-impermeable boundary member between the gas-impermeable boundary member and the porous radiator in the radiant heating zone. Alternatively, it can be formed in an independent device completely different from this device and introduced into the adjacent area.

The heated reforming zone has a porous heat receiver supporting a catalyst.

As the catalyst, for example, a nickel-based catalyst is preferably used. Such catalysts are known per se.

Furthermore, methods for supporting these catalysts on porous heat receivers are also known per se. The porous heat receiver, like the porous radiator, can be, for example, a porous metal, a porous metal oxide, a porous ceramic or a porous mineral molded body. These materials depend on the type of catalyst supported.
At the very least, it should not reduce activity. Generally, porous ceramic bodies are preferably used.

The porous heat receiving body is heated by the porous radiator through the gas-impermeable boundary member to a temperature suitable for reforming. When the raw material gas passes through the porous heat receiver, it is heated to a high temperature in the presence of a catalyst to produce reformed gas.

The device of the invention further comprises at least one, preferably both, of a first heat recovery zone and a second heat recovery zone.

The first heat recovery zone is provided on the downstream side of the porous radiator in the radiant heating zone, and the exhaust gas that has passed through the porous radiator (high-temperature gas after imparting sensible heat to the porous radiator) This is the area where steam is generated by recovering sensible heat.

Sensible heat from the exhaust gas can be recovered, for example, by providing a number of tubular bodies across the flow of the exhaust gas and filling the internal passages of the tubular bodies with a granular heating medium or a medium carrying a catalyst.

The second heat recovery zone is provided downstream of the porous heat receiver in the heated zone, and the reformed gas that has passed through the porous heat receiver (heated and reformed by the porous heat receiver) is This is an area where the sensible heat of the reformed gas (reformed gas heated to a higher temperature) is recovered and steam is similarly generated.

To recover the head heat from the reformed gas, for example, a region or a passage filled with a granular heating medium is provided, and the reformed gas is passed through the region or passage to transfer the sensible heat of the reformed gas to the heating medium. The sensible heat recovered by the heating medium can thus be transferred to a second heat recovery area surrounding this area or passage.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The reformed gas production apparatus of the present invention will be described below with reference to the accompanying drawings.

(Example) FIG. 1 shows an embodiment of the reformed gas production apparatus of the present invention.

In Fig. 1, ■ is a combustion chamber which is a radiant heating area, 2 is a porous radiator, 3 is a heat receiving chamber which is a heated reforming area, 4 is a porous heat receiving body on which catalyst is almost uniformly supported, 5 1 is a partition wall that is a gas-impermeable boundary member that partitions the combustion chamber 1 and the heat receiving chamber 3; 6 is a high-temperature combustion gas obtained by combustion of fuel; 7 is an exhaust gas; 8 is a CH.

and H20, 9 is a reformed gas obtained by decomposing raw material gas 8 and is a mixture of H2 and CO, lO
is process water.

Further, 12 is a heat exchanger (second heat recovery zone) that generates steam using the sensible heat of the generated reformed gas 9, and 11 is a heat exchanger (first heat recovery zone) that generates steam using the sensible heat of the exhaust gas 7. ).

In the above device, the sensible heat of the combustion gas 6 is absorbed by the porous radiator 2 by convection heat transfer when it passes through the porous radiator 2, and the porous radiator 2 is heated and radiant heat is released into the device. be done. The emitted radiant heat is received by the heat receiving body 4 as heating and re-radiation of the partition wall 5 when the partition wall 5 is made of a metal material or ceramic, or is received by the partition wall 115 when the partition wall 5 is made of a transparent material such as quartz glass. The heat passes through and is received by the heat receiving body 4, thereby heating the heat receiving body 4.

In the above reactor, the combustion gas 6 passes through the porous radiator 2 to be heated and then discharged as exhaust gas 7, but before that, it is heat exchanged with process water at 11.

During this process, the process water evaporates and becomes water vapor.

In addition, when the raw material gas 8 passes through the heat receiving body 4, it is heated and decomposed by the heat receiving body 4, and becomes a reformed gas 9 containing a mixture of H2 and Co. At 12, the raw material gas 8 is heat exchanged with process water and sent to the outside of the apparatus. It will be done. During this process, the process water evaporates and becomes water vapor.

As mentioned above, the heat absorbed by the porous radiator 2 is given to the heat receiver 4 by radiation, and the raw material gas 8 is passed through the heat receiver 4 and heated, and is decomposed in the presence of a catalyst to generate and reform. When the gas 9 is obtained and the steam generated by the sensible heat of the produced reformed gas 9 and the exhaust gas 7 is used as a raw material, effective use of heat is achieved. As shown in Example 1 (Table 1), it is known that the temperatures of the exhaust gas 7 and the produced reformed gas 9 at the outlet of the apparatus are significantly reduced.

Table 1 The results in Table 1 show that using the generally cylindrical reformed gas production apparatus of the present invention shown in FIG.
The results are obtained when a mixed gas of ``/H'' and 6.8 kg/H of steam (H2O) is used as the raw material gas, and H29N m ''/H is used as the produced reformed gas.

(Effects of the Invention) As described above, according to the present invention, firstly, residual heat of the exhaust gas 7 and the generated reformed gas 9 can be recovered and the heat can be used effectively.

Secondly, since raw material steam is generated within the process using the recovered heat, the entire reaction system can be simplified, and furthermore, operation and maintenance costs can be saved, among other advantages. It is possible to achieve the desired effect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic explanatory diagram of the reformed gas production apparatus of the present invention. l combustion chamber, 2 porous radiator 3 heat receiving chamber,
4 porous heat receiving body 5 partition wall,
6 Combustion gas 7 Exhaust gas, 8 Raw material gas 9
Reformed gas, IO process water 11 Heat exchanger, 12 Heat exchanger I3 Burner 14
Raw material gas supply pipe 15 Cylindrical reactor, 16 Reformed gas take-off pipe Figure 1 Procedure auxiliary equipment August 1999

Claims (1)

[Claims] 1. An apparatus for producing hydrogen-containing reformed gas from a raw material gas consisting of hydrocarbon gas and sushi team in the presence of a catalyst, comprising: a gas-impermeable boundary member; It has a separate radiant heating area and a heated reforming area, and the radiant heating area and the heated reforming area are located adjacent to each other while forming an independent space through the gas-impermeable boundary member. the radiant heating zone includes a porous radiator formed in an area of the radiant heating zone adjacent to the gas impermeable boundary member through which hot gas can pass, and the heated reforming zone is , a porous heat receiving body supporting a catalyst for producing reformed gas and through which a raw material gas can pass, which is heated via the gas-impermeable boundary member by radiant heat from the porous radiant; A first heat recovery zone that generates steam using the sensible heat of the exhaust gas that has passed through the porous radiator downstream of the porous radiator in the heating zone and/or a porous heat receiving zone in the heated reforming zone. A reformed gas production device comprising: a second heat recovery section that generates steam by using the sensible heat of the reformed gas that has passed through the porous heat receiving body on the downstream side of the porous heat receiving body. 2. A method for producing a reformed gas using the production apparatus according to claim 1, the method comprising: forming a high temperature gas in an area adjacent to the gas-impermeable boundary member in the radiant heating area; The porous radiator is heated to a high temperature by passing through the porous radiator, and a raw material gas consisting of a hydrocarbon gas and steam is placed upstream of the porous heat receiver in the heated reforming zone. is introduced and passed through the porous heat receiver heated by the radiant heat emitted from the porous radiator to generate a reformed gas, and the sensible heat of the exhaust gas that has passed through the porous radiator is converted into a reformed gas. The sensible heat of the reformed gas that has passed through the first heat recovery zone and/or has passed through the porous heat receiver is recovered in a second heat recovery zone to produce at least a portion of the steam used in the reaction. A method for producing reformed gas characterized by: