Its important to know that your thermal oxidizers are made of high quality and in addition it is best to know the basics of how thermal oxidizers work. Here’s a transient outline of thermal oxidizers.
PRINCIPLE OF COMBUSTION
The first perform of the Thermal Oxidizer is to destroy the contaminants within the exhaust coming out of a process. The operation of the Thermal Oxidizer is based on the principle of combustion. The process of combustion is essentially the most commonly used methodology to regulate emissions of natural compounds.
Combustion based systems are at all times simple systems capable of having very high destruction efficiency. These systems typically encompass burners, which ignite the fuel and pollution, and a chamber, which provides the appropriate residence time for the combustion to take place. Combustion is a chemical process arising from the rapid combination of oxygen with numerous elements or chemical compounds resulting in release of heat. The process of combustion has also been referred to as oxidation or incineration.
It’s required to achieve full combustion of the fuel gas so that no further air pollution are added. To achieve full combustion as soon as the contaminated air and fuel have been brought into contact, the next conditions must be provided: a temperature high sufficient to ignite the waste-fuel combination, turbulent mixing of the air and waste-fuel combination, and sufficient residence time for the response to occur. These three conditions are referred to as the “three T’s of combustion”. The rate at which a combustible product is oxidized is drastically affected by temperature. The higher the temperature, the quicker the oxidation response will proceed.
The process of ignition is dependent upon the following factors:
1. Focus of combustibles in the waste stream.
2. Inlet temperature of the waste stream.
3. Rate of heat loss from the combustion chamber.
4. Residence time and flow pattern of the waste stream.
5. Combustion chamber geometry and supplies of construction.
RETENTION CHAMBER DESIGN
Thermal destruction of most organic compounds occurs between 590°F and 650°F. Nonetheless, most hazardous waste incinerators are operated at 1400°F. The time for which the pollution keep in the incinerator is called residence time. The higher the residence time, the lower the temperature will be for the combustion chamber.
The residence time of gases within the combustion chamber is calculated by
t = V / Q
t = residence time, seconds
V = chamber volume, ft3
Q = gas volumetric stream rate at combustion ft3/s.
Adjustments to circulation rates have to be made for the extra combustion air added. For full combustion to happen, every particle of waste and fuel should come in contact with air (oxygen). If this doesn’t happen, unreacted waste and fuel will be exhausted from the stack. Second, not your complete fuel or waste stream is able to be in direct contact with the burner flame.
In most incinerators, a portion of the waste stream could bypass the flame and be blended sooner or later downstream of the burner with the recent products of combustion. A number of strategies are used to improve mixing the air and waste streams, including the use of refractory baffles, swirl-fired burners, and baffle plates. Unless properly designed, many of those mixing devices might create “dead spots” and reduce operating temperatures.
The process of blending flame and waste stream to acquire a uniform temperature for the decomposition of wastes is the most troublesome part in the design of an incinerator. A Thermal Oxidizer should be designed very carefully and with proven methods to achieve maximum mixing of airflows and to keep away from dead spots.
THERMAL OXIDIZER OPERATION
A Thermal Oxidizer consists of a combustion chamber, a burner, and a blower to draw air by means of the entire oxidizer. Together with the contaminant-laden gas stream, air and fuel are continuously delivered to the combustion chamber where the fuel is combusted.
The products of combustion and the unreacted feed stream enter the reaction zone of the unit. The pollutants within the process air are then reacted at elevated temperature. The average gas velocity can range from 10 fps to 50 fps. These high velocities are useful in preventing the particulates from settling down. The energy liberated by the response could also be directly recovered from process or indirectly recovered by utilizing a heat exchanger.
The Thermal Oxidizer should be constructed of fabric which can stand up to high temperatures and the partitions of the equipment are insulated to keep away from overheating of the outside walls of the unit. These models are usually provided with sophisticated flame detection devices. The layer of insulation uncovered in the Combustion Chamber is typically ceramic block that is 7″ thick and a density of 10 lbs./ft3.