WO2011094943A1

WO2011094943A1 - Natural gas additive used for cutting

Info

Publication number: WO2011094943A1
Application number: PCT/CN2010/070534
Authority: WO
Inventors: 张是阳
Original assignee: 秦皇岛远舟工业气体有限公司
Priority date: 2010-02-05
Filing date: 2010-02-05
Publication date: 2011-08-11
Also published as: CN102245746A; CN102245746B

Abstract

A natural gas additive used for cutting is characterized in that it includes (wt%) pentane 78％-93％, 1-pentene 1％-3％, 2,3- dimethylpentane 2％-7％, neohexane 1.5％-3.5％, normal propyl alcohol 1％-5％, 2,2,4- trimethylpentane 0.7％-2％, nitromethane 0.4％-l％, butadiene 0.2％-0.5％, and xylene 0.2％-0.5％. The additive in the natural gas for cutting serves for catalyzing and combustion-supporting, accelerates the natural gas combustion rate, increases the flame temperature, reduces the preheating time and speeds up the combustion reaction of iron with oxygen so as to quicken the cutting rate and further lower the use cost, while the characters of being environmentally friendly and safe are maintained.

Description

Natural gas additive for cutting

The invention relates to the technical field of metal cutting, in particular to a natural gas additive for cutting.

Background technique

There are many methods for metal cutting on the market, such as laser, plasma, gas flame, etc. However, due to the low cost of gas flame cutting and easy to master, it is still the first choice for cutting methods at home and abroad.

For gas flame cutting, there are mainly three kinds of gases, one is natural gas, the other is acetylene gas, and the other is propane and propylene gas. Here are some advantages and disadvantages for these three gases: Table 1

As can be seen from Table 1,

1. The density of natural gas is significantly lower than the density of air. The density of acetylene is close to the density of air, while the propane and propylene gases exceed the density of air. Therefore, when a leak occurs, natural gas is not prone to low concave deposits, making it difficult to reach the explosion range and reducing the possibility of explosion.

2. The relative density of natural gas is also much lower than the density of air. Therefore, the leaked natural gas can be quickly volatilized, and there will not be a large amount of low retention. It is suitable for use in small spaces and relatively closed spaces.

3. The explosion range of natural gas is narrow, which is V4 of acetylene explosion range, so the safety is much higher than acetylene.

4. The ignition point of natural gas is higher than that of acetylene, propane and propylene. Therefore, if you want to ignite natural gas, you should use an open flame, so that it is not safe to ignite the gas due to sporadic low-temperature fire.

5. Natural gas is composed of natural gas. There is no pollutant emission when burning. Acetylene needs to be produced. It consumes a lot of electricity and coke, and it produces a lot of pollutants when it produces acetylene and acetylene. It will affect the health of the human body and pollute the atmosphere. Propane and propylene are by-products of petroleum, in many places. There is a lot of demand, if it is only used for cutting, it is too wasteful.

6. Natural gas is not toxic, and acetylene contains a lot of harmful substances such as hydrogen sulfide and phosphine. Propane and propylene contain simple asphyxiation and anesthesia, which may also have adverse side effects on contact personnel.

7. When natural gas is burning, it has low radiation and no black smoke; while acetylene is easy to accumulate carbon, it is easy to emit black smoke and smoke, which has an impact on human health.

It can be seen that natural gas has broad prospects in the field of gas flame cutting, with good energy saving and environmental protection effects and high safety. However, the deficiency of pure natural gas is that the temperature of the flame is relatively low when it is burned, and it takes a long time to use it for cutting gas, which is not suitable for cutting. Summary of the invention

In view of the defects existing in the prior art, the object of the present invention is to provide a natural gas additive for cutting, which is injected into natural gas to play a catalytic combustion-supporting effect, so that the natural gas burning speed is increased, the flame temperature is increased, and the preheating time is reduced. Accelerate the oxidation (burning) of iron and oxygen, increase the cutting speed, further reduce the cost of use, and still have the characteristics of good environmental protection and high safety.

In order to achieve the above object, the technical solution adopted by the present invention is:

A natural gas additive for cutting, characterized by comprising the following components by mass percentage: pentane 78%-93%;

1-pentene 1%-3%;

2,3 methylpentane 2%-7% _;

New hexane 1.5%-3.5%;

N-propanol 1%-5%;

2, 2, 4 trimethylpentane 0H

Nitromethane 0.4%-1% _;

Butadiene 0.2%-0.5%;

Xylene 0.2% - 0.5%.

The natural gas additive for cutting according to the invention is injected into natural gas to play a catalytic combustion-supporting effect, so that the natural gas burning speed is increased, the flame temperature is increased, the preheating time is reduced, and the iron and oxygen are accelerated. Oxidation (combustion), increasing the cutting speed, further reducing the cost of use, and still has the characteristics of good environmental protection and high safety.

detailed description

The invention discloses a natural gas additive for cutting, characterized in that the following components are included in mass percentage:

Pentane 78%-93%;

1-pentene 1%-3%;

2, 3 methylpentane 2%-7%;

New hexane 1.5%-3.5%;

N-propanol 1%-5%;

2, 2, 4 trimethylpentane 0H

Nitromethane 0.4%-1% _;

Butadiene 0.2%-0.5%;

Xylene 0.2% - 0.5%.

The basic order of mixing of the above components is: pentane + 2, 3 methylpentane + 1-pentene + neohexane + 2, 2, 4 trimethylpentane + nitromethane + n-propanol + dibutyl Alkene + xylene. No special containers, equipment or methods are needed during the mixing process. The raw materials are all added to a closed container in the above-mentioned order (because the raw materials are non-corrosive chemicals, so the commonly used closed metal containers are available). Stir and mix well.

The natural gas additive for cutting according to the invention plays a catalytic role in injecting into natural gas, and has two main functions: First, the addition of the additive accelerates the combustion of the natural gas, and the natural gas is burned more fully, thereby increasing the combustion temperature and More heat is applied. The main component of natural gas is methane. Normally, when methane and oxygen are completely burned, carbon dioxide and water will be produced. However, in reality, this effect is often not achieved. When methane is burned, some of it may not burn. It is a methane state volatilization, and a part of it is carbon monoxide. When carbon monoxide and oxygen are burned to generate carbon dioxide, a part of the heat is also applied, so a large amount of heat is not used. Adding an additive changes the situation and can promote complete combustion of methane. , so that it can be used as much as possible, the most heat is released, and the effect of energy saving and emission reduction is achieved. Second, the cutting of metal is actually the oxidation (burning) process of iron and oxygen, and the addition of additives is beneficial to iron and oxygen. Oxidation reaction Enhance the role of the cutting speed. The following are specific examples of several natural gas additives for cutting according to the present invention:

Example 1. pentane 828 g _; 1-pentene 10.8 g _; 2,3 methylpentane 21.6 g _; fresh hexane 9 g _; n-propanol 14.4 g _; 2, 2, 4 trimethylpentane 7.2 g _; Methane 4.5g _; butadiene 2.7g _; xylene 1.8g Table 2

Example 2. 1335 g of pentane; 21 g of 1-pentene; 46.5 g of 2,3 methylpentane _; 30 g of neohexane; 31.5 g of n-propanol; 16.5 g of 2,2,4 trimethylpentane _; Methane 9g _; butadiene 6g _; xylene 4.5g Table 3

Example 3. 2295 g of pentane; 62.1 g of 1-pentene; 137.7 g of 2,3 methylpentane; 59.4 g of neohexane; 78.3 g of n-propanol _; 29.7 g of 2,2,4 trimethylpentane; Nitromethane 18.9g _; butadiene 10.8g _; xylene 8.1g Table 4

Example 4. pentane 936 g _; 1-pentene 34.8 g _; 2,3 methylpentane 81.6 g _; fresh hexane 40.8 g _; n-propanol 58.8 g _; 2, 2, 4 trimethylpentane 24 g; Methane 12g; butadiene 6g _; xylene 6g

Example 5. pentane 1620 g; 1-pentene 52 g; 2,3 methylpentane 122 g _; fresh hexane 62 g; n-propanol 82 g; 2, 2, 4 trimethylpentane 30 g; nitromethane 16 g; Butadiene 8g _; xylene 8g Table 6

Component name Proportion range Add amount ( g) Percentage pentane 78 93 1620 81.00%

1-pentene 1 3 52 2.60%

2, 3 methylpentane 2 7 122 6.10% neohexane 1.5 3.5 62 3.10% n-propanol 1 5 82 4.10%

2, 2, 4 trimethylpentane 0.7 2 30 1.50% nitromethane 0.4 1 16 0.80% butadiene 0.2 0.5 8 0.40% xylene 0.2 0.5 8 0.40%

2000 Example 6. pentane 2232 g; 1-pentene 24 g; 2,3 methylpentane 48 g; fresh hexane 36 g; n-propanol 24 g; 2, 2, 4 trimethylpentane 16.8 g _; nitromethane 9.6 g _; butadiene 4.8g _; xylene 4.8g

Table 7

But its average boiling point is very low only

: Inject into the natural gas pipeline. When passing through the pipeline, the pipeline number is transmitted to the control system to control the output control signal. When the pump receives this signal, the gas quality will be 0.6%~: L%. Take

Table 8

As can be seen from Table 8,

1. The density and relative density of natural gas added with additives are close to that of natural gas. It does not change the nature of natural gas itself, and the density is much lower than the density of air. Therefore, the volatility is still good, and low concave deposits will not occur, such as leakage. Rapid evaporation, can ensure the safety of the production site, but also suitable for use in small spaces.

2. The explosion range of natural gas after adding additives is similar to that of natural gas, and the safety is still significantly better than acetylene.

3. After adding the additive, the ignition point is slightly higher than that of the natural gas, and the non-open flame cannot be ignited, which improves the safety performance.

4. The flame temperature of the natural gas after adding the additive is obviously improved, and the calorific value released per unit volume is more, so that the preheating time is greatly shortened when the natural gas is used as the cutting gas, and the cutting is also performed when cutting. Both the effect and the speed of the cut are improved.

5. Since the cutting gas uses natural gas as the base gas, the added additive only acts as a catalyst, and does not change the nature of the natural gas, so that it does not generate a large amount of pollutants when burned, which is much larger than other cutting gases. Reduce the harm to the human body.

6. After adding additives, natural gas is less prone to tempering, and the anti-vibration and explosion-proof performance is better than acetylene. Flame temperature comparison test after adding natural gas to additives

1, the basic conditions

1) Environmental conditions: Ambient temperature 20 ° C, atmospheric pressure 101.325 kPa

2) Test gas: natural gas, natural gas after adding additives, additive addition amount: 1% of natural gas quality

3) Test tool: Infrared thermometer (Made in Germany, model HEITRONCS)

2. Test method: Under the same gas pressure and oxygen pressure, the natural gas and the natural gas added with the additive are respectively connected to the cutting moment and ignited, the cutting moment is adjusted to the state of the cutting flame, and the infrared thermometer is used to detect the maximum temperature of the flame. .

3. Test data: gas pressure is 0.04MPa, oxygen pressure is 0.4MPa

4, test results

The average temperature of the tested natural gas flame was 2556.2 ° C. The average temperature of the natural gas flame after adding the additive was 3185.2 ° C. The temperature of the natural gas flame was significantly increased after the addition of the additive.

Steel plate cutting speed comparison test

1. Basic conditions:

1) Cutting test materials and specifications: AH32, thickness S=25mm

2) Cutting length: 2400mmX8= 19200mm

3) Cutting equipment: semi-automatic cutting machine, No. 2 cutting nozzle

4) Cutting type: straight cutting

5) Type of gas for test: Natural gas after adding additive, acetylene

2, test method: stopwatch timing

4. Test results:

Cutting speed ratio: 421/379=1.1108

Claims

Claim

1 . A natural gas additive for cutting, characterized by comprising the following groups by mass percentage: pentane 78%-93%;

1-pentene 1%-3%;

2, 3 methylpentane 2%-7%;

New hexane 1. 5% - 3.5%;

N-propanol 1%-5%;

2, 2, 4 trimethylpentane 0. 7%-2%;

Nitromethane 0. 4 ⁰ /ο-1%;

Butadiene 0. 2%-0. 5%;

Xylene 0. 2%-0. 5%o