Method and system for improving combustible gas containing high-alkane organic matter by thermal plasma

Abstract

The present invention discloses a combustible gas thermal plasma improvement system containing high alkane organic matter, comprising a plasma torch, a plasma torch driving power supply, and a combustible gas inlet and an oxygen-supplementing air inlet respectively connected to different positions of the plasma torch, wherein the inlet is connected to a gas storage tank via an inlet pipe, and a flow meter 1 and an inlet valve 1 are connected in series to the inlet pipe; the oxygen-supplementing air inlet is connected to a high-pressure gas pump via an oxygen-supplementing pipe, and a flow meter 2 and an inlet valve 2 are also connected in series to the oxygen-supplementing pipe; the plasma torch comprises a plasma torch anode and a plasma torch cathode, and the distance between the cathode head and the oxygen-supplementing air inlet is a predetermined distance; and an air outlet is provided at the end of the plasma torch. The present invention also provides an improvement method. The present invention has strong practicability and functionality and can be widely used in the field of combustible gas technology.

Description

Technical Field

[0001] The invention relates to the field of combustible gas, and in particular to a method and system for thermal plasma improvement of combustible gas containing high alkane organic matter. Background Art

[0002] Gas engines are power equipment that use combustible gas as fuel. The most commonly used combustible gases include natural gas, biogas, liquefied petroleum gas, coke oven gas, and biomass pyrolysis gas. The characteristics of these combustible gases are that they are mainly composed of a certain component and contain other combustible components. For combustible gases with more complex components, such as biomass pyrolysis gas or coke oven gas, since the air-fuel ratio and anti-explosion properties of each combustible component are different, the use of a unified standard is prone to gas engine detonation, incomplete combustion, or low efficiency.

[0003] Studies have shown that: the same volume percentage of CO in the fuel burns in the combustion chamber The efficiency is higher than CH4. When the fuel C atoms are the same, converting fuel gas into CO gas is more beneficial to the combustion chamber than converting it into CH4. Improved efficiency. The greater the concentration of high-carbon hydrocarbons in gas fuel, the lower its methane value, and the easier it is to produce knock, such as propane, butane and pentane. The working efficiency of gas fuel engines depends to a large extent on the flammability of the mixture. The ignition temperature of hydrogen and carbon monoxide is lower than that of methane, and the maximum combustion speed is fast. Combustible gases with hydrogen and carbon monoxide as the main components are easier to ignite and start, and the efficiency of the engine is high. For biomass pyrolysis gas, it contains a high concentration of light coke (high alkane) components, which are prone to coking and carbon deposition when used directly in gas engines. Therefore, in order to improve the performance of gas engines, simplify the design of gas engines, and improve the efficiency of gas engines, it is very necessary to improve the combustible gas containing a variety of high-carbon hydrocarbon compounds so that these components can be converted into low-carbon hydrocarbon components or into hydrogen and carbon monoxide.

[0004] At present, combustible gas is basically used directly without deep modification. For combustible gas produced by biomass, some people have studied the technology of converting heavy coke components into light coke using catalytic modification technology. Since this technology requires the use of an external heat source, it consumes a lot of power; the added oxygen has high control requirements and there is a risk of explosion. If too much oxygen is added, a large amount of water and carbon dioxide will be produced, resulting in a decrease in the calorific value of the combustible gas; the catalyst is easily deactivated, and it is still far from practical application. Summary of the invention

[0005] In view of the above problems, the present invention proposes a method and system for improving combustibles containing high alkane organic matter.

[0006] The technical solution provided by the present invention is:

[0007] A system for thermal plasma improvement of combustible gas containing high alkane organic matter, characterized in that it comprises a plasma torch, a plasma torch driving power supply, and a combustible gas inlet and an oxygen-supplementing air inlet respectively connected to different positions of the plasma torch, wherein the inlet is connected to a gas storage tank via an inlet pipe, and a flow meter 1 and an inlet valve 1 are connected in series to the inlet pipe; the oxygen-supplementing air inlet is connected to a high-pressure air pump via an oxygen-supplementing pipe, and a flow meter 2 and an inlet valve 2 are also connected in series to the oxygen-supplementing pipe; the plasma torch comprises a plasma torch anode and a plasma torch cathode, and the distance between the cathode head and the oxygen-supplementing air inlet is a predetermined distance; and an outlet is provided at the end of the plasma torch.

[0008] Furthermore, the oxygen supplementary air inlet is located at the head end of the plasma torch.

[0009] Furthermore, the gas storage tank is used to store the combustible gas to be modified, and the high-pressure gas pump is used to transport oxygen.

[0010] Furthermore, a channel for gas circulation is provided inside the plasma torch, and the predetermined spacing is 1-5 times of the inner diameter of the channel.

[0011] Furthermore, both the first intake valve and the second intake valve are manually controlled valves.

[0012] The present invention also provides a technical solution:

[0013] A method for improving a combustible gas containing high-alkane organic matter by thermal plasma, which is improved by using the above-mentioned improvement system, specifically comprising the following implementation steps:

[0014] Open the first inlet valve, and adjust the flow rate to a certain value according to the inlet volume requirement of the subsequent combustible gas using equipment. The flow rate value is read by the first combustible gas flow meter;

[0015] Start the plasma torch ignition, light the plasma torch, and determine the reasonable working current according to the combustible gas flow rate;

[0016] Start the high-pressure air pump and adjust the second inlet valve. The specific flow rate value is calculated and determined according to formula (1):

[0017] q=(0.1-0.5)×Q×W×W0×ρ / K0 (1)

[0018] Where: q is the air supply volume, unit is m 3 / h, Q is the combustible gas flow rate, unit is m 3 / h, W is the mass percentage of organic components with carbon content above 3 in the combustible gas, in %, and W0 is the amount of oxygen required for complete combustion of organic components with carbon content above 3 per unit mass, in m 3 , ρ is the air density at working pressure, unit is kg / m 3, K O It is the mass percentage of oxygen in the air, in %.

[0019] The advantages of the present invention compared with the prior art are:

[0020] A system with a plasma torch, a gas storage tank, a high-pressure gas pump and an oxygen supply pipe is proposed, which is directly applied to a combustible gas containing high alkane organic matter, and oxygen is appropriately added. Under the high temperature of the thermal plasma, the high alkane organic matter contained in the combustible gas is decomposed into low alkane organic matter, and finally converted into hydrogen and carbon monoxide, thereby generating a combustible gas with hydrogen and carbon monoxide as main components. Since the thermal plasma is directly applied to the gas to be treated, the treatment efficiency is high. Moreover, since the temperature in the thermal plasma is as high as 3000°C, the moisture and carbon dioxide in the combustible gas can also be decomposed, so the control accuracy of adding oxygen is not required to be high, and finally a combustible gas containing high concentrations of hydrogen and carbon monoxide can be generated, thereby solving the problems of gas engine detonation in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a connection structure diagram of an embodiment of the present invention;

[0022] Figure 2 2 is a side view of an air intake in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The following is combined with Figure 1 and 2 The present invention is described in further detail.

[0024] A combustible gas containing high alkane organic matter thermal plasma improvement system comprises a plasma torch, a plasma torch driving power supply 3, and a combustible gas inlet 4 and an oxygen-supplementing air inlet 5 respectively connected to different positions of the plasma torch, wherein the inlet 4 is connected to a gas storage tank 9 via an inlet pipe 13, and a flow meter 7 and an inlet valve 8 are connected in series to the inlet pipe 13; the oxygen-supplementing air inlet 5 is connected to a high-pressure gas pump 10 via an oxygen-supplementing pipe 14, and a flow meter 11 and an inlet valve 10 are also connected in series to the oxygen-supplementing pipe 14; the plasma torch comprises a plasma torch anode 2 and a plasma torch cathode 1, and the distance between the head of the cathode 1 and the oxygen-supplementing air inlet 5 is a predetermined distance 15; and an outlet 6 is provided at the end of the plasma torch.

[0025] The oxygen supplement air inlet 5 is located at the head end of the plasma torch.

[0026] The gas storage tank 9 is used to store the combustible gas to be improved, and the high-pressure gas pump 10 is used to transport oxygen.

[0027] A channel 17 for gas circulation is provided inside the plasma torch, and the predetermined spacing 15 is 1-5 times of the inner diameter of the channel 17 .

[0028] Both the intake valve 1 8 and the intake valve 2 10 are manually controlled valves.

[0029] When the above system is used to improve combustibles containing high alkane organic matter, the following implementation process is included:

[0030] Open the air inlet valve 8, and adjust the flow rate to a certain value according to the air intake requirement of the subsequent combustible gas using equipment. The flow rate value is read by the combustible gas flow meter 7;

[0031] Start the plasma torch ignition, light the plasma torch, and determine the reasonable working current according to the combustible gas flow rate;

[0032] Start the high-pressure air pump 10, adjust the air inlet valve 10, and calculate the specific flow rate value according to formula (1):

[0033] q=(0.1-0.5)×Q×W×W0×ρ / K0 (1)

[0034] Where: q is the air supply volume, unit is m 3 / h, Q is the combustible gas flow rate, unit is m 3 / h, W is the mass percentage of organic components with carbon content above 3 in the combustible gas, in %, and W0 is the amount of oxygen required for complete combustion of organic components with carbon content above 3 per unit mass, in m 3 , ρ is the air density at working pressure, unit is kg / m 3 , K O It is the mass percentage of oxygen in the air, in %.

[0035] In summary, the present invention directly acts on combustible gas containing high-alkane organic matter, and appropriately adds oxygen, and under the high temperature of thermal plasma, decomposes the high-alkane organic matter contained in the combustible gas into low-alkane organic matter, and finally turns into hydrogen and carbon monoxide, thereby producing combustible gas with hydrogen and carbon monoxide as main components;

[0036] Since thermal plasma is used to directly act on the gas to be treated, the treatment efficiency is high; and since the temperature in the thermal plasma is as high as 3000°C, it can also decompose the moisture and carbon dioxide in the combustible gas, so the control accuracy of adding oxygen is not high, and finally a combustible gas containing high concentrations of hydrogen and carbon monoxide can be produced.

[0037] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A thermal plasma reforming system for combustible gas containing high-alkane organic matter, characterized in that: The invention comprises a plasma torch, a plasma torch driving power supply, and a combustible gas inlet and an oxygen-supplementing air inlet respectively connected to different positions of the plasma torch, wherein the inlet is connected to a gas storage tank via an inlet pipe, and a flow meter 1 and an inlet valve 1 are connected in series to the inlet pipe; the oxygen-supplementing air inlet is connected to a high-pressure air pump via an oxygen-supplementing pipe, and a flow meter 2 and an inlet valve 2 are connected in series to the oxygen-supplementing pipe; the plasma torch comprises a plasma torch anode and a plasma torch cathode, and the distance between the cathode head of the plasma torch and the oxygen-supplementing air inlet is a predetermined distance; an outlet is provided at the end of the plasma torch; the oxygen-supplementing air inlet is located between the cathode head and the outlet of the plasma torch; the gas storage tank is used to store the combustible gas to be improved, and the high-pressure gas pump is used to transport oxygen; a channel for gas circulation is provided inside the plasma torch, and the predetermined distance is 1 to 5 times the inner diameter of the channel; both the inlet valve 1 and the inlet valve 2 are manually controlled valves.

2. A method for modifying combustible gas containing high-alkane organic matter by thermal plasma, characterized in that: The improvement is carried out by adopting the improvement system described in claim 1, which specifically includes the following implementation steps: Open the first inlet valve, and adjust the flow rate to a certain value according to the subsequent inlet volume requirement of the combustible gas using equipment. The flow rate value is read by the first combustible gas flow meter; start the plasma torch ignition, light the plasma torch, and determine the reasonable working current according to the combustible gas flow rate; start the high-pressure gas pump, adjust the second inlet valve, and the specific flow rate value is calculated and determined according to formula (1): q=(0.1~0.5)×Q×W×W0×ρ / K0(1) Where: q is the air supply volume, unit is m 3 / h, Q is the flow rate of combustible gas, unit is m 3 / h, W is the mass percentage of organic components with carbon content above 3 in the combustible gas, in %, and W0 is the amount of oxygen required for complete combustion of organic components with carbon content above 3 per unit mass, in m 3 , ρ is the air density at working pressure, unit is kg / m 3 , K0 is the mass percentage of oxygen in the air, the unit is %, and 0.1~0.5 means 0.1 to 0.5 times.

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