[0025] Example 1-12
[0026] Collect the waste gas produced by the sewage biochemical aeration tank and sludge aging tank of a petrochemical enterprise, and wash it with the sewage discharged from the enterprise in the packed tower. The gas-liquid contact time is 2-5s, and the washing strength is 3-7L washing liquid/M 3 Exhaust gas. The exhaust gas after washing is adsorbed by activated carbon, and the adsorption process is switched by two adsorbers. When the concentration of odorous components in the exhaust gas is higher than GB 162976-1996 "Comprehensive Emission Standard of Air Pollutants", GB14554-93 "Emission Standard of Odor Pollutants" , Local emission standards and other relevant limit values, switch (specific operations can be determined according to needs). The volumetric space velocity of the adsorption process is 1500hr -1. Desorption regeneration adopts 250℃ steam regeneration, and the space velocity is 50hr -1. Or use catalytic combustion exhaust tail gas for desorption regeneration, the regeneration temperature is 140℃, and the space velocity is 80hr -1 , Regenerating gas is combined with high-VOC waste gas produced by grease traps, flotation tanks, etc. After washing and adsorption treatment, the treatment effects of low VOC waste gas with different concentrations are shown in Table 1.
[0027] Exhaust gas composition and concentration
[0028] The adjustment tank, grease trap, and flotation tank of the sewage treatment plant of the enterprise are covered and sealed, and the discharged organic waste gas containing sulfide is mixed with the above-mentioned intermittent or continuous desorption regeneration gas. The mixed gas has the following 4 treatment processes:
[0029] (1) Concentration homogenization/desulfurization-catalytic combustion. Introducing a concentration homogenizer, the homogenizer can be filled with reagents that have the functions of organic concentration homogenization and desulfurization (concentration homogenization and desulfurization can also be carried out in two devices respectively, and the concentration homogenizer is filled with organic concentration homogenization The desulfurizer is filled with desulfurization reagents). After the exhaust gas has been homogenized and desulfurized, the organic concentration is monitored. If the concentration is higher than 25% of the lower explosive limit, it will be diluted with air before entering the heat exchanger, otherwise It enters the heat exchanger directly and exchanges heat with the high-temperature gas discharged from the reactor. The exhaust gas after the heat exchange enters the heater. If the exhaust gas has reached the required reactor inlet temperature, the heater does not work; otherwise, the heater works and changes the temperature of the exhaust gas. After being heated to the required reactor inlet temperature, it enters the catalytic combustion reactor for treatment, and the purified gas is discharged after heat exchange and cooling.
[0030] (2) Concentration homogenization-regenerative combustion. Introduce a concentration homogenizer, the homogenizer is filled with activated carbon, molecular sieve, alumina and their mixtures. After the exhaust gas passes through the organic matter concentration homogenizer, monitor the organic matter concentration. If the concentration is higher than 25% of the lower explosive limit, it is mixed with air to dilute, otherwise it enters directly Thermal storage combustion device; after thermal storage combustion treatment, purify gas emissions.
[0031] (3) Concentration homogenization/desulfurization-thermal storage catalytic combustion. Introducing a concentration homogenizer, the homogenizer can be filled with reagents with the functions of organic concentration homogenization and desulfurization (concentration homogenization and desulfurization functions can also be completed in two devices), and the exhaust gas is subjected to organic concentration homogenization and desulfurization treatment , Or directly enter the heat storage catalytic combustion reaction device, or mix with appropriate amount of air to ensure that the concentration of organic matter in the exhaust gas is controlled below 25% of the lower limit of organic matter explosion, and then enter the heat storage catalytic combustion reaction device; after heat storage catalytic combustion treatment, purification Gas emissions.
[0032] (4) Concentration homogenization-desulfurization/catalytic combustion. Introduce a concentration homogenizer, the homogenizer is filled with activated carbon, molecular sieve, alumina and their mixtures, the exhaust gas passes through the organic matter concentration homogenizer, or directly enters the inlet and outlet heat exchangers of the catalytic combustion reactor, or mixes with an appropriate amount of air to ensure The concentration of organic matter in the exhaust gas is controlled below 25% of the lower limit of the organic matter explosion, and then enters the heat exchanger. The exhaust gas after heat exchange enters the heater. If the exhaust gas has reached the operating temperature required by the high-temperature desulfurizer, the heater does not work; otherwise, The heater works to heat the exhaust gas concentration to the required temperature and enters the desulfurizer bed for desulfurization (the desulfurizer and the catalytic combustion catalyst are installed in the same reactor, and the exhaust gas first passes through the desulfurizer bed and then enters the catalytic combustion catalyst bed) After that, it enters the catalytic combustion reactor for treatment, and the purified gas is discharged after heat exchange and cooling.
[0033] The exhaust gas purification treatment conditions in each example are listed in Table 2, and the purification treatment effect under each condition is listed in Table 3. The material volume filling amount in the concentration homogenizer is 500L. Among them, the composition of S1 desulfurizer is: 85wt% Fe 2 O 3 , 5wt% Al 2 O 3 , 5wt% NaOH, 5wt% talc powder, formed by tableting; S2 desulfurization agent composition: 85wt% ZnO 3 , 5wt% Al 2 O 3 , 5wt% NaOH, 5wt% methyl cellulose, add appropriate amount of water and extrude into a strip. The C1 catalyst is impregnated and supported on a honeycomb ceramic carrier with 0.3wt% Pt, 0.14wt% Pd and 2.1wt% CeO 2 Prepared, the C2 catalyst is impregnated on the honeycomb ceramic carrier to support 0.4wt% Pt and 2.5wt% CeO 2 be made of. The heat storage body is a honeycomb ceramic.
[0034] Table 2 Comprehensive catalytic combustion purification treatment conditions for exhaust gas
[0035] Real
[0036] Real
[0037] Real
[0038] Real
[0039] Note 1: Φ2, etc. indicate the diameter of the ball, Φ3×4 indicates the diameter (3) and length (4) of the bar, and the unit is mm. Different concentrations of homogenized substances are equal to the volume ratio.
[0040] Note 2: Desulfurization activated carbon is FSTS-3 commercial desulfurization and total hydrocarbon concentration leveling agent produced by Fushun Petrochemical Research Institute.
[0041] Example
[0042] Sulfur removal rate refers to the removal rate of hydrogen sulfide and organic sulfur compounds, which are physically adsorbed, chemically adsorbed or converted into sulfur oxides; VOC in the above table is calculated as total methane hydrocarbons.
