CN203159209U - Carbon dioxide-methane self-heating reforming reactor - Google Patents

Abstract

The utility model discloses a carbon dioxide-methane autothermal reforming reactor, which comprises a furnace body, a burner, a gas distributor, a mixer, a combustion chamber, a catalytic reaction bed and a gas collection chamber; The top is inserted into the mixer; the gas distributor is arranged in front of the end of the burner; the mixer, the combustion chamber, the catalytic reaction bed and the gas collection chamber are arranged in the furnace body from top to bottom. The reforming reactor utilizes the heat generated during the oxidation process of oxygen and methane to realize the self-supply of heat for the carbon dioxide-methane reforming reaction, which not only reduces investment and operation costs, but also improves the conversion efficiency of methane.

Description

Carbon dioxide-methane autothermal reforming reactor

technical field

The utility model relates to the field of carbon-chemical industry, in particular to a carbon dioxide-methane autothermal reforming reactor.

Background technique

The increasing shortage of fossil energy and serious environmental pollution are two major crisis problems facing the world today. The serious impact of the greenhouse effect on the climate and environment has made people pay more and more attention to the issue of _CO2 emission reduction. Using _CO2 as a carbon and oxygen resource through high-temperature catalytic conversion to prepare syngas It is the key development direction of large-scale chemical utilization of _CO2 . Using CO ₂ as raw material, the process of reforming and transforming methane emitted from coal chemical industry and coal bed methane utilization process to produce synthesis gas can realize the efficient utilization of CO ₂ and CH ₄ greenhouse gases at the same time, and reduce the emission of greenhouse gases. The recycling of carbon resources in energy chemicals has huge economic benefits, so the CH ₄ -CO ₂ reforming reaction is considered to be the core technology for the effective utilization of carbon resources in the future coal chemical industry.

At present, there is no example of industrialization of methane and carbon dioxide reforming to produce synthesis gas. The key points and difficulties are mainly the lack of catalysts with excellent performance such as not easy to deposit carbon, not easy to block, not easy to deactivate, high conversion efficiency, good stability, etc., and safe and reliable. Convenient, flexible start and stop, long service life and other reasonably designed reactor devices. According to the thermodynamic calculations in the book "Thermodynamics of Gasification and Gas Synthesis Reactions" ([Soviet Union] Lavlov et al., translated by Wu Yue), it can be known that the methane carbon dioxide reforming reaction is a strong endothermic reaction. From the thermodynamic analysis process, the temperature Only when the temperature is above 600°C can synthesis gas be produced. As the reaction temperature rises, the reaction conversion rate increases and the synthesis gas yield increases. The source of heat under such high temperature conditions is also one of the key points and difficulties in the process.

At present, the pure oxygen reformers at home and abroad are all reformers (also known as secondary furnaces) for the reforming reaction of methane and steam, and the reformer for the reforming reaction of carbon dioxide and methane has not been reported or used.

The current reformer for the reaction of methane and steam reforming has the following defects:

1. The conversion efficiency is low, and the conversion of 30% to 90% of methane needs to rely on the primary furnace installed in the front of the secondary furnace.

2. Both methane and steam reformers need to replenish a large amount of water vapor. In addition to meeting the needs of methane and steam reforming reactions, additional water vapor is required for carbon removal, which increases operating costs and increases the cost of subsequent water vapor separation. operating costs, and there is no reformer that does not require make-up water steam only for reforming methane and carbon dioxide.

3. In the traditional two-stage reformer, methane and oxygen are easily mixed unevenly, causing the oxygen to not be consumed in the combustion section, and to damage the catalyst in the catalytic section after entering the catalytic section.

Utility model content

The technical problem to be solved by the utility model is to provide a carbon dioxide-methane autothermal reforming reactor, which can improve methane conversion efficiency and reduce production cost.

In order to solve the above-mentioned technical problems, the carbon dioxide-methane autothermal reforming reactor of the present invention mainly includes a furnace body, a burner, a gas distributor, a mixer, a combustion chamber, a catalytic reaction bed and a gas collection chamber; The nozzle is inserted into the mixer from the top of the furnace body; the gas distributor is arranged in front of the end of the burner; the mixer, combustion chamber, catalytic reaction bed and gas collection chamber are arranged inside the furnace body from top to bottom.

Preferably, the carbon dioxide-methane autothermal reforming reactor can also be equipped with a cooling system, such as a water jacket, at the end of the burner outside the furnace.

The outer side of the catalytic reaction bed and the outlet of the gas collection chamber may be equipped with multiple temperature measuring elements, such as thermocouple thermometers.

Compared with the secondary furnace, the carbon dioxide-methane autothermal reforming reactor of the present invention has the following advantages and beneficial effects:

1. It is a reactor device designed for the reforming reaction of carbon dioxide and methane, which can convert the "greenhouse gas" carbon dioxide into chemical raw materials and energy with added value, and can not add water vapor or add a small amount of water vapor according to the process requirements .

2. The heat generated during the oxidation process of oxygen and methane is used to realize self-supply of heat for strongly endothermic reforming reaction under high temperature conditions, without additional external heat supply.

3. A single reactor can be used to convert methane into synthesis gas with a methane content of 0.1-2%, which not only has high conversion efficiency, but also reduces investment and operating costs.

4. A mixer, a gas distributor and a combustion chamber are used, and the combustion chamber has enough space so that the oxygen can be completely burned in the combustion chamber, and the gas distribution at the entrance of the catalyst bed is uniform.

Description of drawings

Fig. 1 is a schematic diagram of a carbon dioxide-methane autothermal reforming reactor device of the present invention.

Fig. 2 is a schematic diagram of the gas distributor in the carbon dioxide-methane autothermal reforming reactor of the present invention.

Fig. 3 is a schematic diagram of a single channel of feed gas in the carbon dioxide-methane autothermal reforming reactor of the present invention.

Fig. 4 is a schematic diagram of dual feed gas channels in the carbon dioxide-methane autothermal reforming reactor of the present invention.

The reference signs in the figure are explained as follows:

1: furnace body

2: Gas distributor

3: Refractory lining

4: Water jacket

5: Mixer

6: Combustion chamber

7: Catalytic reaction bed

8: Gathering chamber

9, 10: thermocouple thermometer

11: burner

Detailed ways

In order to have a more specific understanding of the technical content, characteristics and effects of the present utility model, now in conjunction with the illustrated embodiment, the details are as follows:

As shown in Figure 1, the carbon dioxide-methane autothermal reforming reactor of this embodiment includes a furnace body 1, a gas distributor 2, a refractory lining 3, a water jacket 4, a mixer 5, a combustion chamber 6, and a catalytic reaction bed Layer 7, plenum 8, multiple thermocouple thermometers 9, 10 and burner 11. in:

The gas distributor 2 is circular and is arranged in front of the end of the burner 11. The gas distributor 2 is non-uniformly opened with a plurality of circular through holes, and these holes are arranged in a coaxial ring shape, and the opening density of the inner ring is greater than the opening density of the outer ring, as shown in Figure 2.

The refractory lining 3 is filled in the inner wall of the furnace body 1 .

The water jacket 4 covers the outside of the furnace body 1 . Since the combustion of oxygen and methane will generate high temperature, it is necessary to install a forced convection cooling system at the end of the burner 11 to cool the burner 11 with cooling water flowing through the burner 11 .

The mixer 5, the combustion chamber 6, the catalytic reaction bed 7 and the gas collection chamber 8 are sequentially arranged inside the furnace body 1 from top to bottom. The aspect ratio of the mixer 5 is 2-3, preferably 2. The combustion chamber 6 is conical, and its height is 3 to 5 times, preferably 5 times, the diameter of the mixer 5 . The catalytic reaction bed 7 is filled with a certain amount of Ni-Ca-Zr catalyst, and a plurality of thermocouple thermometers 9 are installed outside. A thermocouple thermometer 10 is installed at the outlet of the gas collection chamber 8 .

When the carbon dioxide-methane reforming reaction is carried out, oxygen enters the burner 11 from the oxygen pipeline, and flows to the end of the burner 11 along the axial direction; the raw material gas rich in carbon dioxide and methane (can be a gas rich in methane, or can be Gases rich in methane and carbon dioxide at the same time, such as natural gas, coke oven gas, oil field gas, refinery gas, coal bed methane, methanol synthesis purge gas, Fischer-Tropsch synthesis purge gas, any one or a combination of several.) Then enter the gas distributor 2 along the direction perpendicular to the tangent line of the top of the mixer 5 (one-side or double-side tangent intake can be used, as shown in Figures 3 and 4), and enter the gas distributor 2 at an average flow rate and the high-speed injection at the end of the burner 11. Oxygen is uniformly mixed in the elongated mixer 5, and a combustion reaction occurs at the moment of mixing, and then injected into the upper part of the conical combustion chamber 6 through a single hole.

The raw material gas after combustion enters the catalyst bed 7 from the combustion chamber 6, and under the action of Ni-Ca-Zr catalyst, carbon dioxide-methane reforming reaction is carried out, and the reaction space velocity is 1000-50000h ^-1 , preferably 5000-20000h ^-1 . The synthesis gas produced after the reaction enters the gas collection chamber 8 and flows out from the outlet of the gas collection chamber 8, with a methane content of 0.1-2%.

Claims (10)

1. Carbon dioxide-methane autothermal reforming reactor is characterized in that, comprises body of heater, burner, gas distributor, mixer, combustor, catalytic reaction bed and gas collection chamber; A mixer is inserted; the gas distributor is arranged in front of the end of the burner; the mixer, combustion chamber, catalytic reaction bed and gas collection chamber are arranged inside the furnace body from top to bottom in sequence. 2. The reforming reactor according to claim 1, characterized in that, the inner wall of the furnace is filled with a refractory lining. 3. The reforming reactor according to claim 1, further comprising a cooling system installed at the end of the burner outside the furnace. 4. The reforming reactor according to claim 3, wherein the cooling system is a water jacket. 5 . The reforming reactor according to claim 1 , wherein the gas distributor is circular and has a plurality of through holes unevenly opened. 6 . 6 . The reforming reactor according to claim 5 , wherein the through holes on the gas distributor are arranged in a coaxial ring shape, and the opening density of the inner ring is greater than that of the outer ring. 7. The reforming reactor according to claim 1, characterized in that, the aspect ratio of the mixer is 2-3. 8 . The reforming reactor according to claim 1 , wherein the combustion chamber is conical, and its height is 3 to 5 times the diameter of the mixer. 9. The reforming reactor according to claim 1, characterized in that, Ni-Ca-Zr catalyst is filled in the catalytic reaction bed. 10. The reforming reactor according to claim 1, characterized in that a temperature measuring element is installed outside the catalytic reaction bed and at the outlet of the gas collection chamber.

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