CN109395622B - Diesel steam atomization device and control method - Google Patents

Abstract

The diesel steam atomization device comprises a diesel nozzle, wherein the inner diameter of the diesel nozzle is connected with diesel and a steam pipeline, an annular gap of the diesel nozzle is connected with a carbon dioxide protection gas pipeline, a diesel pressure gauge, a diesel cut-off valve and a diesel flow regulating valve are sequentially arranged in the running direction of the diesel pipeline, a steam regulating valve and a steam cut-off valve are sequentially arranged in the running direction of the steam pipeline, and a carbon dioxide protection gas cut-off valve and a carbon dioxide protection gas regulating valve are sequentially arranged in the running direction of the carbon dioxide protection gas pipeline. According to the invention, the flow of diesel oil is precisely controlled, the atomization of the diesel oil is realized through the pipeline pressure difference of steam and diesel oil, the diesel oil ejector is protected on line in real time through the protective gas, and the service life of equipment is prolonged. The invention ensures the sufficient atomization and jet flow speed of the outlet of the diesel nozzle by controlling the pressure difference between the steam and the diesel mixing inlet end, is favorable for fully mixing diesel and combustion-supporting gas, avoids the occurrence of insufficient combustion and improves the combustion efficiency.

Description

Diesel steam atomization device and control method

Technical field

The invention belongs to the technical field of coal chemical heating furnaces, and particularly relates to a diesel steam atomization device and a control method.

Background technique

In the large-scale coal gasification technology, an efficient and energy-saving preheating system for large reactors is an important component. Common natural gas combustion systems have shortcomings such as low combustion calorific value, long heating time, and high combustion costs. The emergence of diesel combustion devices has increased the calorific value of combustion flue gas and greatly improved work efficiency. However, there are also problems caused by insufficient diesel atomization. Problems such as low combustion efficiency.

The process of atomizing liquid fuel into many tiny particles is an extremely complex physical process. It is mainly the process of interaction between external forces (friction force, impact force) and internal forces (adhesion force, surface tension) on the oil flow surface. If the external force is greater than the internal force, the oil flow will be broken into small particles. In order to improve the atomization quality, the fuel is first required to have a certain injection pressure. The higher the pressure, the finer the atomized oil droplets. Secondly, the fuel is required to have smaller viscosity and surface tension, which can reduce the internal force of the oil droplets and improve the atomization quality. In addition, increasing the relative velocity of oil droplets to air can also improve the atomization quality, which is due to the increase in the external force of air resistance.

Contents of the invention

In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a diesel vapor atomization device and a control method, which is conducive to the complete mixing of diesel and combustion-supporting gas, avoids insufficient combustion, improves combustion efficiency, and is suitable for different working conditions. diesel combustion environment.

In order to achieve the above object, the device used in the present invention includes a diesel burner with an inner diameter and an annular gap. The inner diameter of the diesel burner is connected to the diesel and steam pipelines, and the annular gap of the diesel burner is connected to the carbon dioxide protective gas pipeline;

The diesel pipeline is equipped with a diesel pressure gauge, a diesel cut-off valve and a diesel flow regulating valve in sequence in the direction of the flow;

The steam pipeline is equipped with a steam regulating valve and a steam cut-off valve in sequence in the direction of the water flow, and a pressure difference gauge is also installed between the diesel pipeline and the steam pipeline;

The carbon dioxide protective gas pipeline is equipped with a carbon dioxide protective gas cut-off valve and a carbon dioxide protective gas regulating valve in sequence in the direction of the tap flow, and a blower with a carbon dioxide purge cut-off valve connected to the diesel pipeline is also installed on the carbon dioxide protective gas pipeline. Sweep the pipes.

The steam cut-off valve is located behind the steam regulating valve and as close as possible to the diesel burner.

The inlet end of the purge pipe is located on the carbon dioxide protective gas pipe at the front end of the carbon dioxide protective gas cut-off valve. After the purge pipe outlet pipeline is connected to the diesel cut-off valve, the meeting position is as close as possible to the diesel cut-off valve.

One end of the pressure differential gauge is installed on the steam pipeline between the steam regulating valve and the steam cut-off valve, and the other end is installed on the diesel pipeline at the rear end of the oil flow regulating valve. The positive and negative pressure points of the differential pressure gauge are located on the steam pipe. After the regulating valve and the diesel flow regulating valve.

The control method of the present invention includes the following steps:

1) Open the carbon dioxide purge cut-off valve, set the diesel flow regulating valve to a 5% opening, and purge the diesel burner;

2) Open the carbon dioxide protective gas cut-off valve, set the carbon dioxide protective gas regulating valve to a 10% opening, and the flow rate is about 50Nm3/h, and perform gas protection on the diesel burner annular gap;

3) When the pressure of the diesel pressure gauge reaches 3.0MPa, the steam regulating valve is given an opening of 9%, the steam cut-off valve is opened, and the steam is introduced into the diesel burner;

4) Close the carbon dioxide purge cut-off valve, open the diesel cut-off valve, and control the diesel flow to 100kg/h through the diesel flow regulating valve.

5) When the diesel flow rate stabilizes at 100kg/h, adjust the opening of the steam regulating valve to 15%. At this time, the pressure difference is 35kPa;

6) When stopping the device, close the diesel cut-off valve, open the carbon dioxide purge cut-off valve, set the diesel flow regulating valve and steam regulating valve to 5% and 9% opening respectively, purge the diesel pipeline for 10 minutes and then close the steam cut-off valve 7 , the steam regulating valve is given an opening of 0.

The present invention ensures sufficient atomization and jet velocity at the diesel nozzle outlet by controlling the pressure difference between the mixing inlet ends of steam and diesel, which is conducive to the full mixing of diesel and combustion-supporting gas, avoids the occurrence of insufficient combustion, and improves combustion efficiency. , suitable for diesel combustion environments under different working conditions.

Compared with the prior art, the beneficial effects of the present invention are:

1) The steam atomization method of diesel is realized. By controlling the pressure difference between the mixing inlet of steam and diesel, it ensures sufficient atomization and jet velocity at the outlet of the diesel nozzle, which is conducive to the full mixing of diesel and combustion-supporting gas and avoids combustion. The occurrence of insufficient conditions improves combustion efficiency.

2) Improved the working life of diesel burner. Through the purge and carbon dioxide protective gas system for the burner, the burner is prevented from being blocked during use and burned out at high temperatures, and the working life of the burner is greatly extended.

Description of drawings

Figure 1 is a schematic structural diagram of the present invention.

In the picture: 1. Diesel pressure gauge; 2. Diesel cut-off valve; 3. Diesel flow regulating valve; 4. Diesel burner; 5. Steam regulating valve; 6. Pressure difference gauge; 7. Steam cut-off valve; 8. Carbon dioxide blower Sweep the cut-off valve; 9. Carbon dioxide protective gas cut-off valve; 10. Carbon dioxide protective gas regulating valve.

Detailed ways

The embodiments of the present invention will be described in detail below with reference to the drawings and examples.

Referring to Figure 1, the present invention includes a diesel burner 4 with an inner diameter and an annular gap. The inner diameter of the diesel burner 4 is connected to the diesel and steam pipelines, and the annular gap of the diesel burner 4 is connected to the carbon dioxide protective gas pipeline;

The diesel pipeline is equipped with a diesel pressure gauge 1, a diesel cut-off valve 2 and a diesel flow regulating valve 3 in sequence in the direction of the flow;

A steam regulating valve 5 and a steam cut-off valve 7 are installed in sequence in the direction of the steam pipe's tap flow. The steam cut-off valve 7 is as close as possible to the diesel burner 4, and a pressure difference meter 6 is also installed between the diesel pipe and the steam pipe. One end of the table 6 is installed on the steam pipe between the steam regulating valve 5 and the steam cut-off valve 7, and the other end is installed on the diesel pipe at the rear end of the oil flow regulating valve 3. The positive and negative pressure points of the pressure difference table 6 are at the steam behind the regulating valve 5 and the diesel flow regulating valve 3;

The carbon dioxide protective gas pipeline is equipped with a carbon dioxide protective gas cut-off valve 9 and a carbon dioxide protective gas regulating valve 10 in sequence in the direction of the tap flow, and a blower with a carbon dioxide purge cut-off valve 8 connected to the diesel pipeline is also installed on the carbon dioxide protective gas pipeline. The purge pipe inlet end is located on the carbon dioxide protective gas pipe at the front end of the carbon dioxide protective gas cut-off valve 9. After the purge pipe outlet line is connected to the diesel cut-off valve 2, the meeting position should be as close as possible to the diesel cut-off valve 2.

The control method of the present invention is as follows:

Taking a large circulating fluidized bed gasifier oven as an example, the gasifier pressure is 2.3MPa, and the furnace temperature is 600°C when the device is put into use. The specific operating steps are:

1) Open the carbon dioxide purge cut-off valve 8, set the diesel flow regulating valve 3 to a 5% opening, and purge the diesel burner 4;

2) Open the carbon dioxide protective gas cut-off valve 9, set the carbon dioxide protective gas regulating valve 10 to a 10% opening, and the flow rate is about 50Nm ³ /h, and perform gas protection on the diesel burner 4 annular gap;

3) When the pressure of the diesel pressure gauge 1 reaches 3.0MPa, the steam regulating valve 5 is given an opening of 9%, the steam cut-off valve 7 is opened, and the steam is introduced into the diesel burner 4;

4) Close the carbon dioxide purge cut-off valve 8, open the diesel cut-off valve 2, and control the diesel flow rate to 100kg/h through the diesel flow regulating valve 3.

5) When the diesel flow rate stabilizes at 100kg/h, adjust the opening of steam regulating valve 5 to 15%. At this time, the pressure difference is 35kPa;

6) When stopping the device, close the diesel cut-off valve 2, open the carbon dioxide purge cut-off valve 8, set the diesel flow regulating valve 3 and the steam regulating valve 5 to 5% and 9% opening respectively, purge the diesel pipeline for 10 minutes and then close it. Steam cut-off valve 7 and steam regulating valve 5 are given an opening of 0.

The present invention ensures sufficient atomization and jet velocity at the diesel nozzle outlet by controlling the pressure difference between the mixing inlet ends of steam and diesel, which is conducive to the full mixing of diesel and combustion-supporting gas, avoids the occurrence of insufficient combustion, and improves combustion efficiency. , suitable for diesel combustion environments under different working conditions.

Claims (2)

1. The diesel steam atomization device is characterized by comprising a diesel burner (4) with an inner diameter and an annular gap, wherein the inner diameter of the diesel burner (4) is connected with a diesel pipeline and a steam pipeline, and the annular gap of the diesel burner (4) is connected with a carbon dioxide protection gas pipeline;

the diesel pipeline is sequentially provided with a diesel pressure gauge (1), a diesel cut-off valve (2) and a diesel flow regulating valve (3) in the running direction;

the steam pipeline is sequentially provided with a steam regulating valve (5) and a steam cut-off valve (7) in the running direction, and a differential pressure meter (6) is arranged between the diesel pipeline and the steam pipeline;

the carbon dioxide protection gas pipeline is sequentially provided with a carbon dioxide protection gas shut-off valve (9) and a carbon dioxide protection gas regulating valve (10) from the incoming flow direction, and a purging pipeline which is communicated with the diesel oil pipeline and provided with a carbon dioxide purging shut-off valve (8) is also arranged on the carbon dioxide protection gas pipeline;

the steam cut-off valve (7) is positioned behind the steam regulating valve (5) and is as close to the diesel burner (4) as possible;

the inlet end of the purging pipeline is positioned on a carbon dioxide protection gas pipeline at the front end of a carbon dioxide protection gas cut-off valve (9), the outlet pipeline of the purging pipeline is connected to the back of a valve of the diesel cut-off valve (2), and the joint position is as close to the diesel cut-off valve (2) as possible;

one end of the differential pressure gauge (6) is arranged on a steam pipeline between the steam regulating valve (5) and the steam cut-off valve (7), the other end of the differential pressure gauge is arranged on a diesel pipeline at the rear end of the diesel flow regulating valve (3), and the positive and negative pressure taking points of the differential pressure gauge (6) are positioned behind the steam regulating valve (5) and the diesel flow regulating valve (3).

2. The diesel steam atomization control method based on the diesel steam atomization apparatus as set forth in claim 1, characterized by comprising the steps of:

1) Opening a carbon dioxide purging cut-off valve (8), setting a 5% opening degree of a diesel flow regulating valve (3), and purging a diesel burner (4);

2) Opening a carbon dioxide protection gas cut-off valve (9), and performing gas protection on an annular gap of the diesel burner (4) by setting the opening of a carbon dioxide protection gas regulating valve (10) to be 10 percent and the flow rate to be 50 Nm/h;

3) When the pressure of the diesel pressure gauge (1) reaches 3.0MPa, the steam regulating valve (5) gives 9% of opening, the steam cut-off valve (7) is opened, and steam is introduced into the diesel burner (4);

4) Closing a carbon dioxide purging cut-off valve (8), opening a diesel cut-off valve (2), and controlling the diesel flow to be 100kg/h through a diesel flow regulating valve (3);

5) When the diesel flow is stabilized at 100kg/h, the opening of the steam regulating valve (5) is regulated to 15%, and the differential pressure value of the differential pressure meter (6) is 35kPa;

6) When the device is stopped, the diesel oil cut-off valve (2) is closed, the carbon dioxide purging cut-off valve (8) is opened, the opening degrees of the diesel oil flow regulating valve (3) and the steam regulating valve (5) are respectively set to be 5% and 9%, the steam cut-off valve (7) is closed after the diesel oil pipeline is purged for 10min, and the opening degree of the steam regulating valve (5) is set to be 0.