JPS63232853A - Catalyst for gas turbine burner - Google Patents

Abstract

PURPOSE:To improve the low-temp. ignitability and high-temp. durability of the title catalyst by depositing specified amts. of a noble metal element, a rare-earth element, and the nickel and magnesium as the promoter on an alumina carrier layer provided on a heat-resistant carrier to form the catalyst. CONSTITUTION:An alumina slurry contg. the oxide or salt of a rare-earth element is coated on the surface of a heat-resistant carrier, dried, and baked at 600-1,000 deg.C to form an alumina layer carrying the rare-earth element. The heat-resistant carrier having the alumina carrier layer is dipped in the mixed soln. of a noble metal element compd., a magnesium compd., and a nickel compd. to deposit the noble metal element, nickel element, and magnesium element, and the catalyst for a gas turbine burner is obtained. The amts. of the nickel and magnesium to be deposited on the catalyst carrier are respectively controlled to 5-20pts.wt. and 0.5-5pts.wt.

Description

[Detailed Description of the Invention] [Objective of the Invention (Field of Industrial Application) The present invention relates to a catalyst body used in a catalytic combustion type gas turbine combustor, and more specifically, to
The present invention relates to a catalyst body for a combustor made of linseed wood.

(Prior Art) In recent years, with the depletion of petroleum resources and the like, in order to use energy resources efficiently, it has become desirable to burn fuel at as high a temperature as possible in, for example, gas turbines.

However, the conventional method is to ignite and burn a mixture of fuel and air using a spark plug, etc.
Inside the combustor, there is a high temperature section that partially exceeds zooo'c. and.

It is known that nitrogen oxides (NOx) are produced in large quantities in this high temperature section, causing problems such as environmental pollution.

In order to solve such problems, a combustion method using a catalyst (hereinafter referred to as a catalytic combustion method) has recently been proposed in contrast to the above-mentioned combustion method.

This method uses a catalyst to combust a mixed gas. According to this method, combustion can be started at a relatively low temperature, and the combustion temperature rises gradually without reaching a maximum value. The temperature also decreases.

This is effective from the standpoint of heat resistance of the combustor itself.2Especially, when air containing nitrogen is used as the gas containing oxidizing gas, it is possible to extremely reduce the generation of NOx. . In this catalytic combustion method,
It is required that the catalyst used satisfies both low-temperature ignitability and high-temperature durability at the same time. Specifically, 3
It is desirable to ignite at a temperature of 50°C or lower and to have long-term durability at temperatures of 900°C or higher.

Conventionally, as a catalyst body for a gas turbine combustor of this catalytic combustion method, for example, a catalyst body formed by supporting a noble metal element such as platinum (Pt) or palladium (Pd) on an alumina carrier layer formed on a heat-resistant carrier. , and a catalyst body in which rare earth elements are supported in addition to the above noble metals on an alumina carrier layer (JP-A-49-43586, JP-A-49-43586;
0-105536) and the like are known.

Regarding the former, the smaller the particle size of the noble metal particles supported, the better the low-temperature ignitability.

However, on the other hand, the heat resistance of this catalyst is 500°C.
For example, in a temperature range of 600℃ or higher,
The noble metal particles supported on the alumina carrier layer may begin to aggregate, reducing the active surface area necessary for catalytic reaction with the gas mixture, resulting in a decrease in its activity. The problem is that the smaller it becomes, the more noticeable it becomes.

On the other hand, although the latter has superior high-temperature durability compared to the former, its high-temperature durability and low-temperature ignitability are not compatible under high temperatures such as those in gas turbine combustors, making it impractical. It's hard to say.

(Problems to be Solved by the Invention) As described above, it is difficult for conventional catalyst bodies for gas turbine combustors to satisfy both of the two characteristics of low-temperature ignitability and high-temperature durability, and there is still room for improvement. is left behind.

It is an object of the present invention to solve these conventional problems and provide a catalyst body for a gas turbine combustor that has both good low-temperature ignitability and high-temperature durability.

[Structure of the Invention] (Means for Solving the Problems) As a result of intensive research to achieve the above object, the present inventor has developed a catalyst body in which noble metal elements and rare earth elements are supported on an alumina carrier layer. , furthermore, predetermined amounts of nickel (Ni) and magnesium (M
The present inventors have discovered that significant effects can be obtained by simultaneously supporting g), and have completed the present invention.

That is, the catalyst body for a gas turbine combustor of the present invention has #
A catalyst body for a gas turbine combustor, comprising: a thermal carrier; an alumina carrier layer formed on the heat-resistant carrier; a noble metal element, a rare earth element, and a promoter metal element supported on the alumina carrier layer, It is characterized in that the promoter metal elements are nickel and magnesium, and the amounts of nickel and magnesium supported on the alumina carrier layer are 5 to 20 parts by weight and 0.5 to 5 parts by weight, respectively.

In the catalyst body for a gas turbine combustor of the present invention, the heat-resistant carrier used is not particularly limited as long as it has stable properties in a high-temperature melting atmosphere of about 1300 ° C. For example, nisilite, Examples include ceramic carriers such as mullite, α-alumina, zirconia spinel, and titania. Also,
Although the shape of this carrier is not particularly limited, it is preferably honeycomb-shaped in order to reduce pressure loss under high wind speeds.

Furthermore, the noble metal elements supported on the alumina carrier layer are not particularly limited, and examples include conventionally used platinum (pt), palladium (Pd),
Rhodium (Rh) or a mixture thereof can be mentioned, and it is preferable that the supported amount of these is set to 20% by weight or more based on the alumina carrier layer. For example, lanthanum (La), praseodymium (Pr), neodymium (N
d), etc., or a mixture thereof are preferred. The supported amount of these rare earth elements is 5% relative to the alumina support in terms of t-oxide.
It is preferable to set the amount to 2 (wt%). In the catalyst body of the present invention, in addition to the above two component elements, Nj is added to the alumina carrier layer as a cocatalyst metal element.
and Mg are supported on the alumina carrier layer.
It is necessary to set it so that g is 0.5 to 5 weight fire. If the supported amount of either N55 or Mg deviates from the above range, the synergistic effect obtained by allowing both to coexist will be lost.

The catalyst body for a gas turbine combustor of the present invention is manufactured, for example, as follows.

That is, first, an alumina slurry containing an oxide or salt of a rare earth element is applied to the surface of a heat-resistant carrier, and then dried and fired to form an alumina carrier layer supporting a rare earth element. The firing temperature at this time is set to, for example, 600 to 0000/min.

Next, the heat-resistant carrier on which the alumina carrier layer is formed is immersed in a mixed solution obtained by dissolving a noble metal element compound and a promoter metal element compound, so that the noble metal element and the promoter metal element are supported on the alumina carrier layer. At this time, it is preferable to use, for example, chloride, nitrate, organometallic compound, etc. as the compound of each of the above elements.
The entire heat-resistant carrier is fired at 700 to 1000°C to obtain the catalyst body for a gas turbine combustor of the present invention.

(Example) Example work (1) Production of catalyst body for gas turbine combustor 24 g of lanthanum nitrate was added to 125 g of alumina sol (solid content 80% by weight), mixed in a ball mill for 2 hours, and the resulting mixture was molded into a cordierite honeycomb shape. An alumina carrier layer supporting lanthanum was formed by applying the solution to a carrier (200 cells per inch, 1 tllJL), drying, and firing at 900° C. for 5 hours.

Then, in an aqueous solution in which 28 g of palladium chloride, 26 g of nickel chloride and 4.8 g of magnesium chloride were dissolved,
The honeycomb-shaped carrier obtained above was immersed, dried, and then calcined at 600°C for 3 hours to support Pd, Ni, and Mg in the alumina carrier layer, thereby obtaining the catalyst body of the present invention. Briefly, this catalyst body was activated by heat treatment at 550° C. for 3 hours in a hydrogen atmosphere.

(2) Evaluation test of catalyst body (gas turbine combustion test) The catalyst body obtained above was incorporated into a simulator of a catalytic combustion type gas turbine combustor, and its combustion characteristics were evaluated.

The combustion conditions at this time were a gas flow rate of 30 m/sec,
The fuel concentration is methane 3%, the amount of catalyst is 30cc, and the combustion temperature is 1.
J) The ignition temperature and combustion efficiency of methane after 100 hours were measured and the results are shown in the table.

Examples 2 to 7, Comparative Examples 1 to 7 Catalyst bodies were prepared in the same manner as in Example 1, except that the amount or type of promoter metal element supported on the alumina carrier layer was varied as shown in the table. After manufacturing, similar evaluation tests were conducted and the results are shown in the table.

[Effects of the Invention] As is clear from the above explanation, the catalyst body for a gas turbine combustor of the present invention has excellent low-temperature ignitability, and has extremely high combustion efficiency after 100 hours, which is an indicator of its high-temperature durability. It was confirmed that it was. Furthermore, since the generation of NOx is also prevented, its industrial value is extremely large.

Claims (1)

[Claims] Gas turbine combustion comprising: a heat-resistant carrier; an alumina carrier layer formed on the heat-resistant carrier; a noble metal element, a rare earth element, and a promoter metal element supported on the alumina carrier layer. catalytic catalyst body, wherein the promoter metal elements are nickel and magnesium, and the amounts of nickel and magnesium supported on the alumina support layer are 5 to 20 parts by weight and 0.2 parts by weight, respectively.
A catalyst body for a gas turbine combustor, characterized in that the amount is 5 to 5 parts by weight.