Xinjiang Shaanxi Cable Factory Waste Gas Treatment Ningxia

Xinjiang Shaanxi Cable Factory Waste Gas Treatment NingxiaThe * * VOCs exhaust gas treatment system composed of zeolite molecular sieve impeller in series catalytic oxidizer (CO) first adsorbs VOCs pollutants from the exhaust gas discharged by the zeolite molecular sieve impeller, converting the originally high concentration and low air volume exhaust gas into low air volume and high concentration exhaust gas through a 20 fold concentration ratio, reducing the cost of back-end treatment equipment.

⑵ The high concentration exhaust gas desorbed from zeolite molecular sieve enters a CO furnace at a temperature of 500 ℃ to decompose VOCs molecules. The reaction equation of VOCs in the CO furnace is as follows:

CxHy+(x+y/4)O2--------xCO2+(y/2)H2O

Using plate heat exchangers to heat desorbed gas is safe and reliable.

=Working principle: The pharmaceutical organic mixed waste gas to be processed is first treated by an induced draft fan to remove dust and impurities from the waste gas. Otherwise, direct adsorption will block the micropores of the zeolite, affecting the adsorption effect or even rendering it ineffective. After preliminary filtration, the "relatively pure organic waste gas" enters the zeolite rotary adsorption device for adsorption and purification treatment. The organic substances are trapped inside by the force of the rotary zeolite *, and the clean gas is discharged. After a period of adsorption, the zeolite rotary reaches saturation, and the rotary rotates automatically at a certain speed (1.1-1.4 revolutions per hour) into the cooling and high-temperature desorption zone.

The high concentration exhaust gas desorbed from the zeolite wheel directly enters the incinerator for incineration purification treatment. The cooling gas of the wheel exchanges heat with an independent heating unit, so that the temperature of the desorbed exhaust gas is controlled at around 800-1200 ℃ after heat exchange and enters the desorption zone of the wheel for desorption. The organic matter in the zeolite evaporates from the zeolite after being heated by hot air. At this time, the desorbed exhaust gas belongs toHigh concentration, low airflow, high temperatureThe organic waste gas directly enters the incinerator for oxidation and releases a large amount of energy. The organic matter uses the heat released by its own oxidation and combustion to maintain spontaneous combustion. If the concentration of desorbed waste gas is high enough, it requires very little gas or even no heating for normal use, achieving true energy conservation and environmental protection. At the same time, the entire device is safe, reliable, and free of any secondary pollution.

The operating principle of the system is as follows:

（1）Volatile organic gases can be effectively adsorbed onto the zeolite after passing through a hydrophobic zeolite concentration wheel, achieving the goal of removal.

（2）The clean gas obtained by adsorbing volatile organic compounds on zeolite is directly discharged into the atmosphere through chimneys.

（3）The rotor continues to rotate at a speed of 1.1-1.4 revolutions per hour, while transferring the adsorbed organic matter to the desorption zone.

（4）Utilize a small stream of heated gas in the desorption zone to desorb volatile organic compounds.

（5）After desorption, the zeolite wheel is rotated to the adsorption zone to continuously adsorb volatile organic gases.

（6）The desorbed concentrated organic waste gas is sent to an incinerator for combustion and conversion into carbon dioxide, which is then released into the atmosphere.

（7）Preheat the desorption gas using plate heat exchangers and ducted electric heaters.

Wheel concentration and RTO process principle:

The zeolite wheel uses zeolite molecular sieve as the adsorbent material, which can adsorb and filter organic matter larger than air molecules, while air passes directly through. The rotary wheel is divided into an adsorption zone, a cooling zone, and a desorption zone. The adsorption zone adsorbs organic matter in the exhaust gas, and the purified air is discharged into the atmosphere through the chimney. The exhaust gas heated by the cooling zone is heated by the heat exchange equipment and then passes through the desorption zone to remove the organic matter in the molecular sieve. At this time, the VOC concentration is concentrated 20 times higher than before, and the air volume is reduced to 1/20.

RCOThe principle of catalytic oxidation furnace is that the combustible exhaust gas undergoes thermal oxidation reaction at 1000 ℃, generating carbon dioxide and water. The high-temperature gas produced by thermal oxidation flows through a specially designed plate heat exchanger to preheat the incoming organic exhaust gas.

VOC-RCOOrganic gas catalytic purification device is a purification method that uses catalysts to oxidize and decompose combustible components in harmful gases at lower temperatures. For CnHm and organic solvent steam oxidation decomposition generationandAnd release heat. The reaction equation is:

After being filtered by a flame retardant dust collector, the exhaust gas source enters the heat exchange device and undergoes indirect energy exchange with the high-temperature gas after catalytic reaction, resulting in an increase in the temperature of the exhaust gas source; Gas with a certain temperature enters the preheating chamber for a secondary temperature increase; Enter oneStage catalytic reaction, in which organic waste gas partially decomposes at low temperatures and releases energy, directly heating the waste gas source to increase the gas temperature to the catalytic reaction temperature; After being detected by the temperature detection system, the temperature meets the temperature requirements for catalytic reaction. Upon entering the catalytic reaction chamber, the organic gas decomposes and releases a large amount of heat; The purified gas is converted into cold air flow through a heat exchanger, and after cooling, the gas is discharged by an induced draft fan.

The main structure of the device consists of three parts: the purification device host, the induced draft fan, and the control system. The purification device includes: dust removal flame arrester, heat exchanger, preheater, and catalytic combustion chamber.

Process Flow Diagram

Process flow introduction:

⑴ Zeolite wheel system: The exhaust gas emitted during the production process enters the zeolite wheel for adsorption, and the clean gas after adsorption is discharged through the chimney to meet the standard. A filter is installed at the inlet of the zeolite wheel exhaust gas to remove particulate matter from the exhaust gas. The cooling gas is preheated in the cooling zone of the zeolite wheel and then heated to the required desorption temperature through a heat exchanger, entering the desorption zone of the zeolite wheel to remove the organic components adsorbed in the molecular sieve.

⑵ RCO system: The desorbed exhaust gas is pressurized by the desorption fan and enters the RCO furnace. The RCO furnace uses an electric heater to heat the exhaust gas, controlling the combustion chamber temperature at around 1000 ℃ to ensure the oxidation of VOCs. After high-temperature oxidation treatment, the exhaust gas is recovered by a plate heat exchanger and discharged through the chimney to meet the standard.