Boiler exhaust silencer

Boiler Exhaust Muffler: Uses and Product Advantages

Boiler exhaust silencers are primarily used for effectively silencing steam emissions and other gas emissions in industries such as power, oil, chemical, metallurgy, and textile. They are essential measures for eliminating the noise generated by steam emissions. Various types of boiler exhaust steam are not only high temperature and high pressure but also have a wide frequency bandwidth. The quality of steam exhaust silencers is mainly considered from the following three aspects:

The noise reduction capacity of the muffler meets the requirements of the "Industrial Enterprise Noise Standard."

2. Mufflers are adaptable to various frequencies, high temperatures, and pressures (low, medium, high, ultra-high, subcritical, supercritical).

3. The muffler has excellent structural quality (reasonable size, high strength, long lifespan, and easy installation).

Section 2: Muffler Principle

Boiler exhaust mufflers are primarily based on the "small hole injection" theory combined with impedance expansion and sound absorption. Boilers typically have high steam flow rates and气流noise levels, necessitating an initial passage through a flow-expanding aperture. After passing through multiple apertures, the steam is减压and decelerated in a resistive expansion chamber. The gas then exits through small holes, reducing the sound power in each harmonic band after ejection. The sound pressure level's frequency is elevated to above 20,000 Hz, significantly reducing the noise. However, secondary noise at certain frequencies still requires additional suppression. We install a resistive sound-absorbing cotton structure outside the expansion chamber, designed based on the frequency spectrum characteristics of the residual noise emitted by the pressure-reducing body to effectively absorb the remaining noise. Upon installation as per specifications, the noise reduction can reach 30-45 decibels, meeting the requirements of the <<Industrial Enterprise Noise Standard>>.

Boiler Ignition Exhaust Muffler

This silencer is designed based on the principles of noise reduction. After passing through a single control flow inside the silencer, high-pressure steam enters the pressure-reducing section. It is expanded through a large-volume chamber, forming low-pressure steam that is then ejected. During this process, some of the steam's internal energy is converted into sound energy of a certain frequency. Although the noise power is greatly reduced, it often remains above the standard value due to reasons such as exhaust deviation from the design value. To address this, a double-layered noise-damping housing is designed around the pressure-reducing section, tailored to the frequency spectrum characteristics of the residual noise emitted. It is designed to effectively absorb the remaining noise. After installation according to specifications, the total noise reduction can reach 36 to 45 decibels.

2. Steam Safety Valve Muffler (TA Type)

For the safety valves of boilers and other pressure vessels, the exhaust steam should not only avoid excessive noise but also allow for smooth discharge. Therefore, the commonly used multi-stage throttling and small-hole injection noise reduction methods are not suitable. This restriction has always been a design challenge for safety valve silencers and is also a reason for their poor noise reduction performance. The silencer for safety valves in this application also adopts the noise reduction principle of resistance, injection, and obstruction, replacing the smaller diameter control flow holes with larger diameter expansion holes. This strengthens the resistance and obstruction noise reduction mechanisms structurally, achieving ideal noise reduction effects.

3. Low-pressure Steam Silencer (Type TD)

A large number of industrial and mining enterprises utilize low-pressure boilers with pressures of 0.13 Mpa or less, and there are also numerous low-pressure thermal devices in power plant thermal systems, such as back-pressure turbines, deaerators, auxiliary exhaust blowers, turbine oil pumps, continuous blowdown from boilers, and periodic blowdown, etc. The exhaust pipes of the aforementioned equipment require the installation of mufflers with lightweight structures and easier installation. Our company designs dedicated deaerator series, back-pressure turbine series, and other product lines to cater to different noise reduction needs, meeting the requirements of our customers.

Section 3: Silencer Ordering and Selection

Our silencers are meticulously designed according to various parameters. When ordering exhaust silencers, the following information must be provided to achieve optimal noise reduction:

(1) Steam emission volume (T/h), pressure, temperature.

(2) Steam exhaust pipe diameter and wall thickness.

(3) Structure options include small-hole or anti-spray resistance composite. Generally, users choose the composite silencer for better noise reduction, with internal material of stainless steel and shell material of carbon steel; the connection pipe can be selected for welding or flange connection; the support leg can be chosen in leg or ear structure.

Four, Specifications and Models

Model examples are as follows: PD-6/57

P- Exhaust Muffler Code D--Exhaust Pressure 6-Exhaust Flow Rate 57-Exhaust Pipe Diameter

Note: Temperature is crucial for material selection. Carbon steel can be used for temperatures ≤350℃; stainless steel is applicable for temperatures ≥485℃; and 12Cr1MoV is used for temperatures ≥530℃.

Steam exhaust muffler (composite, suitable for temperatures up to 450 degrees, pressure up to 6.4 Mpa)

TB Type Steam Exhaust Muffler, TB indicating Muffler with Soundproofing Housing (Composite). It is based on the small hole type with an added soundproofing housing, filled with sound-absorbing cotton. The gas enters from the bottom connection and exits from the top. Due to the sound-absorbing cotton filling, it is suitable for pressures up to 6.4 Mpa; otherwise, the filling may be blown out. The housing is made of carbon steel and suitable for temperatures up to 450 degrees.

TB-3.82-10/57 Model Meaning: TB stands for Compound Exhaust Muffler, 57 indicates the outer diameter of the interface is 57mm, and 10 represents the exhaust volume is 10T/H.