How to reduce the noise of the boiler? What should I do if the electric boiler is noisy?

Boiler exhaust muffler is mainly based on the "small hole injection" theory and impedance expansion sound absorption of the silencing effect of research and design, suitable for high pressure, medium pressure, ultra-high pressure gas venting and silencing of power plant special equipment, power plant boiler steam discharge generally flow rate, the test proves that the amount of sillow is related to the flow rate, the flow rate is high, the air flow regeneration noise is improved, and the silencing performance is reduced, so we first control the flow through the hole, and then enter the expansion chamber after a through hole to further reduce the pressure and flow, and the steam is reduced by the large volume pressure and flowIn this process, the air flow is sprayed out through the small aperture, and the sound power of each octave band has been reduced after ejection, and the frequency of the sound pressure level is pushed up to the range above 20000Hz, and the noise is greatly weakened, but the secondary noise of some frequencies also needs to be further silenced. When the user installs according to the requirements, the total sound reduction should reach 30-42 decibels. Make it meet the requirements of the "Noise Standards for Industrial Enterprises".

It is difficult to control the noise of the boiler room, which is due to its following characteristics: there are many power equipment in the boiler room, and the influence of various noise sources on the main body will often change. After the noise of the blower and induced draft fan is controlled, the noise that originally existed as a secondary sound source, such as the water pump, pressure relief exhaust port, regulating valve, slag remover, coal loader, and reducer, will suddenly appear.

The injection noise that occurs when the boiler exhaust is vented has a high sound power (up to 130 140 dB(a)) and covers a wide area. Therefore, when formulating a noise reduction plan, it should be considered as a whole and comprehensive in order to obtain obvious results. There are many types of boilers in our country, and the sound source situation is particularly complicated:

Although more than 70% of them are small and medium-sized coal-fired boilers with a steam volume of less than 4t h, nearly 30% of modern boilers are mainly generated by the atomization and combustion process of oil oil in the boiler itself due to liquid combustion (such as oil) or natural gas and coal gas, followed by fans and pumps, so the treatment scheme must be different from that of coal-fired boilers. When choosing a noise reduction scheme for boiler rooms, different types of treatment measures must be taken according to different sound sources and different environments.

Elimination of noise and pollution of coal-fired boilers: the original exhaust gas treatment system, the original boiler is a chain grate vacuum hot water boiler, and its dust collection process: boiler flue gas boiler induced draft fan water bath dust collector chimney emptying.

The boiler induced draft fan adopts Y5-49, NO5C, 3250 rpm, air volume 5500-10750m3 h, full pressure 3180 2460Pa, motor power 11KW; The boiler blower is 4-74, 2900 rpm, the air volume is 2664 5268m3 h, the full pressure is 1578 989pa, and the motor power is 3kw; The model of the water bath dust collector is unknown. When the furnace is opened, the negative pressure in the furnace is -200Pa, the furnace is kept at 5Pa during the normal operation of the blower, and the motor current of the induced draft fan is 20 21A, which is full load operation. The boiler room is located just a few meters from the residents' houses, and the residents reacted strongly:

First of all, the pollution is serious, residents dare not open the windows during the heating season, and ash often flies into their eyes; Secondly, the vibration and noise are too large, and the vibration sensation in the residents' houses and the whistling sound of the fans are very obvious, which seriously affects the normal life of the residents. In order to reduce pollution, the local environmental protection department stipulated the minimum water level of the boiler's water bath dust collector, and the boiler's company built a wall between the boiler room and the residential building to isolate the noise.

Noise and vibration The cross-section through which the flue gas of this dust collector passes, the velocity is about, and at this speed into the water, when the induced draft fan is turned on, the water in the dust collector boils violently and interacts with the induced draft fan, and the vibration is generated from this. In addition to vibration, the induced draft fan is noisy when it operates. The original system used an induced draft fan with a speed of up to 3250 rpm.

This is good for increasing the wind pressure, but the higher the speed, the louder the noise. When the speed is less than 2500 rpm, the noise is greatly reduced. The gas boiler room is usually designed into three parts: boiler room, fan room and pump room

Noise control measures between boilers: add sound insulation covers, shock absorbers for machinery, set up sound insulation doors and windows and other measures to control the transmission of noise between boilers to the outside world. Noise control measures between fans:

Install mufflers at the air outlet of the fan, install soundproof doors between the fans, increase the diameter of the chimney, and reduce the noise problem of the chimney. Noise control measures in the pump room: sound insulation and sound absorption treatment of walls and roofs.

Some users may have found such a problem, the electric boiler that was originally working silently, suddenly there was noise, and it often made a certain sound, although it will not have much impact on our lives, but if you don't pay attention, it will cause problems with the electric boiler, and can you really stand the noise? Believe it is negative.

There may be a variety of noise in electric boilers, and different frequencies, intensities, and regular sounds are mixed, which makes users upset, so how is the noise generated? How to solve the problem of missing users?

1. The installation of electric boilers is not standardized.

The electric boiler should be installed on the level ground, and there is a certain interval from the wall, so as to ensure its stability, do not place it in uneven places or inclined places, the fit is not tight will lead to noise.

Solution: The electric boiler can be installed on the level ground, and if necessary, it can be fixed by pretending to be a fixture.

Second, there is dust inside the fan.

The fan is a device used for heat dissipation of electric boilers, and if the dust is not removed frequently, it will cause dust to enter the inside of the electric boiler, and the dust on the fan will affect the rotation balance of the fan, resulting in mechanical noise, which may also be caused by the noise caused by the loose fan.

Solution: clean the fan inside the electric boiler before Lahe, check whether the fan is loose, if it is loose, you need to tighten the screws, if the fan shaft is eccentric, it must be replaced.

3. The pump is faulty or has impurities.

If you don't pay attention to the impurities in the heating system, they can penetrate into all corners of the pump, which will cause the noise of the pump to become louder and louder.

Solution: Install a filter on the return pipe and clean the filter regularly.

Fourth, the water quality is not good.

The water quality in the electric boiler heating system is not good, and when it is heated to a higher temperature, it will make a noise of boiling water.

Solution: Use a water treatment device.

The facilities in the boiler room are mainly composed of drums, induced draft fans, steam discharge and water pumps, etc., and the noise generated by them is mainly medium and low frequency, which has a wide range of influences, many changes, and is difficult to control. Improper treatment can lead to a sharp reduction in the life of the boiler and the noise intensity is not weakened.

Specific problems and Hanks sound insulation solutions:

1. Fan noise in the boiler room: The noise intensity of the fan in the boiler room is between 90-105db (a), and a noise muffler can be installed to weaken the noise, and the noise reduction amount is between 30-40db (a).

2. Steam emission noise: the noise card generated during steam discharge is as high as 120db (a), and the noise can also be treated by installing a silencing device for this kind of noise, and the noise reduction device can be between 30-40db (a).

3. Pump noise in the boiler room: The pump noise is above 110db (a), and the sound insulation cover can be installed for comprehensive treatment, and the noise reduction amount is 25-35db (a).

If it is necessary to strengthen the noise control effect of the boiler room, the fan and steam emission equipment can be installed with sound insulation covers, and other equipment such as coal mills can also be treated with vibration and sound absorption.

Note: The temperature in the boiler room is high, and attention must be paid to ventilation and heat dissipation during treatment to ensure that the service life of the equipment itself is not affected.

Boiler room noise control is mainly considered from the following aspects:

First, the gas atmospheric pressure hot water boiler is shock-absorbed.

Second, the hot water circulation pump is shock-absorbed.

Third, the piping system is shock-absorbed.

Fourth, the computer room is soundproofed.

Fifth, boiler blower sound insulation.

Sixth, the cabinet centrifugal fan tuyere is silencing.

Seven, the chimney is silenced.

The design of the boiler room noise control scheme needs to carry out on-site noise survey, and carry out targeted technical design according to the actual working conditions and requirements of the site, such as: equipment installation location, sound source type, noise level and frequency, environmental protection requirements, ventilation and heat dissipation requirements, noise reduction targets, etc.

1. Noise control between boilers

The noise between the boilers is generated by the noise of the slag remover, coal loader and reducer, the blast noise and grate working noise from the inside of the boiler, and the equipment noise from the fan room and the pump room through the sound insulation door. Its sound value is usually 55 to 60 decibels. Due to the ** too scattered.

Therefore, it is impossible to control this part of the noise with any kind of equipment, and can only be controlled by the sound insulation performance of the boiler room itself. If the sound insulation performance of doors and windows does not achieve the expected effect, it is generally solved by adding a door bucket to the door and turning a single-layer window into a double-layer window (the sound insulation of single-layer doors and windows is usually not less than 10 15 decibels according to the different materials).

The noise control of the heating boiler room usually refers to the noise control of the blower, induced draft fan and circulating pump. It does not include noise control between boilers.

2. Noise (vibration) control between pumps

The noise control between the pumps is solved by using the sound insulation performance of the walls of the boiler room and the cast-in-place concrete roof itself. As long as the thickness meets the requirements, no other measures are required. In addition, the problem of personnel access is solved with soundproof doors.

Use a muffler to solve the problem of indoor heat dissipation. Use a vibration damping hose to prevent the transmission of pump vibration. Under the control of the above comprehensive measures, the noise (vibration) between the pumps can be controlled very satisfactorily.

3. Noise control between fans

The noise between the fans is generated by the blower, the induced draft fan and the dust collector. Therefore, its noise control is also solved by using the sound insulation performance of the wall between the fans and the cast-in-place concrete roof. In addition, it is necessary to.

A sufficient number of mufflers are installed on the exterior wall of the fan room. On the premise of ensuring that the noise control effect is not affected, sufficient ventilation area is provided for the air inlet of the blower;

Install acoustic doors for the fan room. On the premise of not affecting the noise control effect, it provides a channel for personnel access and equipment maintenance;

Due to the chimney exhaust gas flow noise and gas flow rate. Therefore, the noise problem of chimney outlet is solved by increasing the diameter of the chimney to reduce the gas flow velocity.

The noise of the boiler room is mainly generated by the boiler blower, boiler water pump, boiler exhaust, etc., and the noise control of the boiler room will also start from these aspects.

1) Install a muffler on the inlet and outlet pipes of the fan to weaken the aerodynamic noise intensity;

2) Install a sound insulation cover for the fan, comprehensively weaken the noise intensity, block the external impact of noise, and the overall sound insulation volume can be between 20-35db(a);

3) The noise of the pump can be comprehensively treated by installing vibration damping devices and sound insulation covers.

Sound absorption, sound insulation, vibration reduction and noise reduction are the main measures taken to control the noise of the boiler room, which can reduce the noise of the boiler room to the specified range.

Boiler room noise control is a comprehensive project, and different schemes will lead to deviations in the treatment effect.

The noise of wall-hung boilers can be roughly divided into the following types:

1.Mechanical noise.

After the boiler runs for a period of time, the fan impeller has too much dust, and the rotation is unbalanced when it rotates, which will form a large noise.

Substandard installation can also cause vibration in boiler operation.

2.Water flow noise.

Poor water flow: The main heat exchanger of the boiler is fouled and blocked, causing a sound vibration.

Excessive water flow: A large amount of air is accumulated in the heat exchanger of the wall-hung boiler (the factors of air in the water: low pressure and increased temperature), or the external water pump is too large, which will produce large water flow noise.

3.Combustion noise.

The use of unqualified smoke pipes or poor connection of smoke pipes, the inner pipe falls off, resulting in noise caused by deignition during combustion.

The thin metal pipe of the gas inlet causes a loud sound at the moment of ignition.

The ignition caused by carbon and dust accumulation in the combustion components makes an abnormal sound during deflagration.

BAI belongs to the local "Environmental Protection Agency" and is responsible for DU. The Law of the People's Republic of China on the Prevention and Control of Environmental Noise Pollution is called environmental noise pollution, which exceeds the environmental noise emission standards stipulated by the state and interferes with the normal life, work and study of others. The decibel of sound is the unit of sound pressure level and is denoted as dB.

Used to indicate the magnitude of the sound. The "Noise Standards for Urban Areas of the People's Republic of China" clearly stipulates the maximum limits of environmental noise in five types of urban areas:

Recuperation area, high-end villa area, high-end hotel area, 50db during the day and 40db at night; In areas dominated by residential, cultural and educational institutions, 55db during the day and 45db at night; residential, commercial, and industrial mixed areas, 60db during the day and 50db at night; Industrial zone, 65db during the day and 55db at night; In the city, the road traffic arterial roads, inland waterways, railway main and secondary trunk areas on both sides, 70db during the day and 55db at night, (night refers to 22 o'clock to 6 o'clock the next morning).

According to the national standard, the noise in residential areas should not exceed 50 decibels during the day and 45 decibels at night. So, what is the noise standard in an indoor environment? Paragraph 4 of Article 5 of the National "Environmental Noise Measurement Methods for Urban Areas" stipulates that when noise measurement is carried out indoors, the indoor noise limit is 10db lower than the standard value of the area.