Overview of coal powder sampler:
The coal powder sampler is mainly used for regular coal powder sampling on the secondary air coal powder pipe of the positive pressure direct blowing coal powder system. Due to the wear and tear of the grinding components of the coal mill, as well as changes in coal type and block size, the fineness of coal powder will undergo significant changes and directly affect the combustion rate of the boiler. Therefore, it is necessary to regularly sample and measure the fineness of coal powder. When the fineness of coal powder exceeds the design value, it is necessary to adjust the opening of the separator folding door in a timely manner or replace the grinding components.
The design of the coal powder sampler adopts compressed air blowing and suction sampling with an air extractor, which avoids the problem of clogging of the sampling port and is easy to sample. The sampling speed is controlled by controlling the compressed air pressure and flow rate. This can obtain a more accurate value of coal powder fineness.
The difference between the coal powder sampler and the same type of production inside is that a pressure regulating valve is installed after the compressed air valve.; Due to the pressure of compressed air provided by power plants being around 6-8Kg, it is difficult to achieve the working pressure required by the coal powder sampling device solely by adjusting the compressed air valve. Sampling distortion often occurs due to high pressure, which does not represent.
Coal powder sampler - potential:
The accurate control and analysis of coal powder fineness in coal-fired power plant boilers is of great significance for the safe and economic operation of boiler units. Currently, the application of positive pressure direct blowing coal powder system in large units is increasing. Due to the fact that the coal powder at the outlet of the coal mill is directly fed into the furnace for combustion by the positive pressure of the secondary air, daily coal powder sampling is not difficult- The general method of using self spraying has poor sampling accuracy and is difficult to seal during sampling, resulting in coal powder leakage, poor working environment, and high labor intensity.
The company has decades of experience in theoretical testing and engineering application research of gas-solid two-phase flow, and has developed a coal powder sampler that can easily achieve constant velocity sampling of coal powder in a positive pressure direct blowing pulverization system. Its main feature is simultaneous constant velocity sampling, which makes the collected powder samples have good representativeness, simple operation, and coal powder leakage, greatly improving the working environment and reducing labor intensity, This is a device for analyzing and sampling the fineness of coal powder in the positive pressure direct blowing pulverization system of power plant boilers on a daily basis.
The coal powder sampler is mainly composed of a sampling tube installed in the inner core of the coal powder pipeline and an external air extraction separation device. The sampling tube can rotate around the support axis, and when sampling, rotate it to a position perpendicular to the pipeline, so that the nozzle installed on the sampling tube is facing the coal powder airflow; After sampling, the sampling tube should be returned to a position parallel to the pipeline, avoiding coal powder airflow and wear; The use of compressed air blowing can prevent coal powder from entering the shell and the core of the sampler and causing blockage, ensuring reliable operation and maintenance.
Coal powder sampler - Energy -:
1. Simultaneously sampling at a constant speed, convenient and fast, representing the sampling process;
2. Fixed on the coal powder pipeline, rotate to the measurement plane during sampling, and place the sampling gun outside the coal powder airflow to minimize wear and tear;
3. Compressed air is used for blowing to avoid blockage of the sampler.
Operating procedure for coal powder sampler:
-Purging and sampling - The sampling tube should be blown clean to prevent coal powder from blocking the sampling tube.
Open the sampling control valve; Close the purge valve; Blow the sampling tube for 1-3 minutes, close all valves to clean the coal powder in the sampling bottle, place the sampling bottle back in its original position, and pay attention to the sealing between the sampling bottle mouth and the separator interface.
2、 Sampling
Sampling - all valves are closed, - open compressed air valve 6; Adjust the pressure of the pressure regulating valve according to the pressure gauge 7 on the compressed air pressure regulating valve, and adjust the compressed air pressure to the required pressure range of 0.05-0.1MPa.
When adjusting the compressed air pressure, open all ball valves to start sampling. The sampling time is determined based on the pressure of the compressed air, usually 1-2 minutes. After sampling is completed, close all valves, remove the sampling bottle, and take out the sample; Return the sampling bottle to its original position and seal the interface.
Working principle of coal powder sampler:
The coal powder sampler is developed using the principles of negative pressure suction and cyclone separation to extract coal powder from the coal powder pipeline and perform solid and gas separation. Please provide an explanation in conjunction with the coal powder sampling process.
During the coal powder sampling process, all valves are in an open state. When compressed air is sprayed out from the outlet pipe, its jet action causes negative pressure at the pipeline connected to the sampling valve, and the gas inside the pipeline is carried out. The separator and its bottom powder collection bottle are closed connections, and only the sampling head and sampling tube can be connected to the outside. So the emergence of negative pressure causes the coal powder in the coal powder pipe to enter the sampling device along the sampling head. The coal powder is separated again in the separator and enters the powder collection bottle. The gas and a small amount of fine powder are separated again from the upper outlet of the separator through the blades in the outlet pipe, and are carried out by compressed air and sent into the coal powder pipeline, which does not cause pollution to the workplace.
The function of adding a blowing valve is to close the blowing valve after coal powder sampling, and open the sampling valve to blow away the residual coal powder in the sampling pipe to prevent the sampling pipe from being blocked by coal powder. And ensure accurate sampling.
The coal powder sampler mainly consists of the following parts:
1. Sampling tube - insert into the coal powder pipeline - with the sampling port facing towards the coal powder airflow, and the coal powder enters the sampling device through this port. The form is sampling.
2. Separators - separate coal powder and gas, and the coal powder is thrown into the wall of the collector by the rotating airflow due to force, and then falls into the collector by force. The separated gas spirals down the wall from top to bottom and then rises along the intermediate path to the bottom. It undergoes secondary separation through the blades at the bottom of the exhaust pipe and is discharged from the outlet of the part, resulting in the separation of coal powder and gas.
3. Sampling bottle - the fixed coal powder sample separated from the separator is collected and stored for calibration purposes.
4. Sampling valve - When sampling coal powder, open this valve and use the negative pressure formed by the exhaust of compressed air from the outlet to suck the air from the separator, so that the coal powder in the coal powder pipeline enters the sampling device from the sampling port for sampling.
5. Blowing valve - When it is necessary to clean the residual coal powder in the sampling pipe, close the sampling valve and pressure regulating valve, and open the blowing valve to use compressed air to blow the sampling pipe.
6. Pressure regulating valve - adjusting the opening of this valve can control the pressure and flow rate of compressed air and change the sampling speed of the sampling device. The pressure cannot be adjusted too high to prevent distortion in coal powder sampling.
7. Pressure gauge - provides intuitive basis for the operation of pressure regulating valves.
-Special specifications can be arranged separately according to user needs for design schemes! Interested parties contact us!
Technical parameters of coal powder sampler model:
Model: MF-XXX
Model description: MF: Coal powder sampler. XXX: Coal powder pipeline diameter.
Instructions for ordering coal powder samplers:
Users are required to provide the following data when placing an order:
1. Order quantity
2. Flute diameter and wall thickness
3. Space installation location
4. Operation mode (electric, manual)
Note: The above production technical specifications are for reference only and are primarily for international design purposes.
