Introduction to the principle of zeolite concentration wheel+three bed RTO:
1. Zeolite concentration wheel+three bed RTO is a waste gas treatment process that combines the principle of large specific surface area of zeolite and different intermolecular forces under different temperature conditions with three bed thermal oxidation technology.
Under low temperature conditions, organic waste gas with high air volume and low concentration in the workshop is collected through pipelines and sent to the front stage for physical interception and filtration; After interception and filtration, the exhaust gas can meet the strict requirements of the zeolite wheel for particle content and particle size. Then the exhaust gas is pressurized by the fan and sent to the zeolite wheel for adsorption and concentration. VOC molecules are adsorbed and retained on its surface, and the exhaust gas passing through the zeolite wheel can be directly discharged.
3. The part of the zeolite wheel that adsorbs a large amount of VOCs enters the high-temperature desorption zone, and the VOC molecules on the zeolite wheel are desorbed using a small amount of high-temperature exhaust gas; The desorbed gas has formed a relatively high concentration of organic gas, which is thermally oxidized through a three bed RTO; Afterwards, carbon dioxide and water are formed and discharged in compliance with standards. At the same time, the heat generated by thermal oxidation can reduce the consumption of auxiliary fuel in the system. When the concentration reaches a certain level, the heat released by thermal oxidation can not only meet the operational needs of the rotating RTO itself, but also provide heat for temperature and humidity regulation and desorption air.
1、 Working principle of zeolite concentration wheel
The zeolite wheel concentration device can be divided into adsorption zone (treatment zone), desorption zone (production zone), and cooling zone, and the concentration wheel operates continuously in each zone.
1. Adsorption zone (treatment zone): After passing through the pre filter, VOCs exhaust gas is adsorbed by honeycomb zeolite in the adsorption zone of the zeolite wheel device. The purified gas (adsorption wind) is discharged from the adsorption zone of the zeolite wheel.
2. Desorption zone (production zone): After the zeolite wheel adsorption is completed, it rotates to the desorption zone. The VOCs waste gas adsorbed on the zeolite wheel is desorbed and concentrated in the desorption zone after hot air treatment. The concentrated wind is desorption wind. The heat source comes from the air heated in the cooling zone and the high-temperature bypass of RTO.
3. Cooling zone: After the desorption of zeolite wheel is completed, it rotates to the cooling zone and cools the zeolite to room temperature with ambient air before rotating to the adsorption zone. Room temperature air is heated through zeolite and reused in the desorption zone.
2、 Working principle of three bed RTO
The three chamber RTO device is equipped with three heat storage chambers, two burners, fans, and air duct channels. The high concentration process waste gas after concentration and desorption by zeolite wheel enters the three chamber RTO system, and is heated to above 800 ℃ by the burner. The waste gas decomposes into CO2 and H2O under high temperature conditions. During the decomposition process, heat is stored in the heat storage tank and used to preheat the newly introduced exhaust gas.
The three room RTO device operates periodically according to the above process. The bottom of the heat storage chamber is equipped with a switching valve and an air duct channel, which can control the direction of exhaust gas inlet and outlet, allowing for alternating intake, exhaust, and blowing of the heat storage chamber.
The control process and switching time interval of RTO directional switching valve are controlled by PLC, and the switching time is set to 1.5-2.0 minutes. Periodic directional switching will evenly distribute heat throughout the combustion chamber, so the temperature of the combustion chamber remains basically constant, reaching the decomposition temperature of the exhaust gas. During normal operation, RTO does not require an external heat source, and only needs natural gas growth to assist combustion when restarted after shutdown.
RTO has set up a high-temperature thermal bypass, which uses excess heat for the wheel desorption function and for heat recovery and reuse, greatly reducing energy consumption.
After passing through a high temperature of 800 ℃, VOCs are mainly converted into CO2 and H2O, and no longer produce hazardous waste. The high temperature generated by RTO is partly used for wheel desorption, and another part of the waste heat is recovered through heat exchangers, directly preheating the gravure production line oven (transformed into a two-layer double oven structure), significantly improving economic and environmental benefits.
Product Features:
1. The economy of treating high air volume and low concentration VOCs.
2. It is easy to correspond to changes in air volume and concentration.
3. Convert the originally high air volume and low concentration VOCs waste gas into low air volume and high concentration waste gas, with a concentration factor of 5-20 times, greatly reducing the specifications of post-treatment equipment and reducing operating costs.
4. The wheel is composed of inorganic oxides, which have non combustible properties and high safety;
Applicable occasions:
Petroleum, chemical, packaging and printing, pharmaceutical and pesticide manufacturing, semiconductor and electronic product manufacturing, furniture manufacturing, automobile manufacturing, leather, enameled wire, shoe manufacturing, coatings, inks, adhesive production, metal casting, etc.