Methods of Optimizing Boiler Efficiency and Reducing NOx Emission
The article explores NOx pollution from fossil fuel combustion, advocating Flue Gas Recirculation (FGR) for up to 50% reduction. It highlights sources, FGR benefits, and
In burners with ventilation motor capacity of 22kW and above, the power circuit and control circuit need to be installed separately due to destructive effects of electrical noise that power circuit or high voltage has on the control devices. With regard to this reason, raadman motor starter (RMS) in which the power circuit is embedded, is introduced. The Most common start ventilation motor is star-Delta and the frequency converter is also called VSD (Variable Speed Drive).
RMS-…-SD-…
A star-delta starter is the most commonly used method for starting a three-phase induction motor. In star delta starting, an induction motor is connected via a star connection throughout the starting period. In order to use this starting method, the motor must be delta connected during a normal run. This starting system has some disadvantages that are mentioned below:
RMS-…-VSD-…
The frequency converter is also called VSD (Variable Speed Drive), VFD (Variable Frequency Drive) or simply drive. The drive consists primarily of two parts; one part converts AC (50 or 60 Hz) to DC and the other part converts DC back to AC, but with a variable frequency of 0-250 Hz. The drive can control the motor speed by controlling the frequency. During start, the drive increases the frequency from 0 Hz up to the network frequency (50 or 60 Hz). By increasing the frequency gradually, the motor can run at its rated speed for that frequency. Since the motor can run at its rated speed, the rated torque is available already from start and the current will be around the nominal current. Normally, the drive trips if the current reaches 1.5 times the rated current. The followings are limitations of starting with a drive:
The article explores NOx pollution from fossil fuel combustion, advocating Flue Gas Recirculation (FGR) for up to 50% reduction. It highlights sources, FGR benefits, and
During the last century, Nitrogen oxide emissions, called NOx, have constantly been increasing. Due to the destructive effects of nitrogen oxides on the health of
The «furnace industry» and products determine the type of flame contact. In many heat treatment processes, where the combustion gases must not come into contact
raadman factory produces burners with firing range of 100 kW to 60000 kW. In burners with ventilation motor capacity of 22kW and above, the power circuit and control circuit need to be installed separately due to destructive effects of electrical noise that power circuit or high voltage has on the control devices. With Regard to this reason, raadman motor starter (RMS) in which the power circuit is embedded, is introduced by the means of this technical document.
A star-delta starter is the most commonly used method for starting a three-phase induction motor. In star delta starting, an induction motor is connected via a star connection throughout the starting period. In order to use this starting method, the motor must be delta connected during a normal run.
This starting system has some disadvantages that are mentioned below:
-Overload current drawn from electric grid at the time of starting
-Current and mechanical shocks at the load torque starting moment
-Current and mechanical shocks to the motor at the moment of changing status from Star to Delta which reduces the motor useful lifespan
-by increasing the current range, the contactors and bimetals sizes are increased
The soft starter makes use of the fact that when the motor voltage is low during start, the starting current and starting torque is also low. During the first part of the start, the voltage to the motor is so low that it is only able to adjust the play between the gear wheels or stretching driving belts, chains, etc. In other words, eliminating unnecessary jerks during the start. Gradually, the voltage and the torque increase so that the machinery starts to accelerate.
This method also has some drawbacks such as:
-high starting current (3 to 5 times of the rated current)
-limitations in number of starting times
-limitations in ambient temperature
-limitations in working cycle and rest period of the device
-high cost
-high sensitivity of power semiconductors
According to the abovementioned limitations, for using soft starter in starting the burner fan, it is necessary to choose a power range which is two times higher than motor power range. Moreover, the soft starter should be selected from among reputable brands
The frequency converter is also called VSD (Variable Speed Drive), VFD (Variable Frequency Drive) or simply Drive. The drive consists primarily of two parts; one part converts AC (50 or 60 Hz) to DC and the other part converts DC back to AC, but with a variable frequency of 0-250 Hz. The drive can control the motor speed by controlling the frequency.
During start, the drive increases the frequency from 0 Hz up to the network frequency (50 or 60 Hz). By increasing the frequency gradually, the motor can run at its rated speed for that frequency. Since the motor can run at its rated speed, the rated torque is available already from start and the current will be around the nominal current. Normally, the drive trips if the current reaches 1.5 times the rated current.
The followings are limitations of starting with a drive:
causing noise and harmonics to the network (needs filter) and high cost
Burner management consists of power circuit and control circuit. The control circuit controls the starter signal in the power circuit. The control circuit normally operates at a lower voltage than the power circuit. So, it is better to install power circuit and control circuit separately.
There are two brackets designed to be connected behind the panel which help to install the panel on desired place.
There are two bases to be connected under the panel which can be screwed to the earth. These bases are designed in such a way that electrical wires can be easily connected via glands under the panel.
IEC (International Electrotechnical Commission) has published standard 60529 for describing a system to classify the degrees of protection provided by the enclosures of electrical equipment. This system is suitable for using with most types of electrical equipment.
IP Code is a coding system to indicate the degrees of protection provided by an enclosure against access to hazardous parts, ingress of solid objects and water. It also provides detailed information regarding the protection.
raadman electrical panels have a high degree of protection (IP 54) due to the following features:
PACKMAN Company was established in February, 1975. The company has started its activity in the field of producing High-Pressure Vessels such as Hot-Water Boilers, Steam Boilers, Pool Coil Tanks, Softeners and Heat Exchangers since 1984.
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