Key Technologies And Experimental Research On VOCs Treatment Of Ship Painting

The paint mist generated during the coating process of the ship is easy to adhere to the surface of the paint removing device because of its small particle size and high viscosity.If the paint mist cannot be removed effectively,it will block the ventilation duct of the spray booth,affecting the intermittent process caused by the painting process.Effective collection and treatment of low-concentration,high-volume VOCs.In this paper,the development of the paint mist and the VOCs waste gas generated during the coating process of Shanghai ship is carried out,and the development of the paint mist purification device without clogging and replacement is carried out.The VOCs in addition to the paint mist are subjected to the adsorption and desorption test to obtain suitable process parameters.Post-designed paint mist efficient capture-VOCs wide load regulation-suction and desorption integration-catalytic oxidation process and equipment,and on this basis,the ship coating exhaust gas treatment pilot test,the following conclusions are drawn:(1)The paint mist cleaning device without blockage and replacement has high paint mist removal efficiency.The separation and removal test of the paint spray of the ship is carried out by using the developed non-blocking and non-replaceable paint mist purifying device.When the inlet paint mist concentration is about 1500 mg/m~3and the wind speed is 7.2 m/s,the average separation of the paint mist particles is carried out.The removal efficiency can be as high as 97.93%,and the removal effect of the paint mist is efficient and stable.(2)When the adsorption temperature is 30?and the adsorption concentration of VOCs is 200 mg/m3,the adsorption capacity of honeycomb activated carbon for VOCs is 0.21 g/g;the adsorption capacity of zeolite molecular sieve for VOCs is0.096 g/g.After 10 times of adsorption-desorption treatment,the adsorption rate of VOCs by honeycomb activated carbon decreased to 71.35%for the first time;the adsorption rate of VOCs by zeolite molecular sieve decreased to 81.15%for the first time.Honeycomb activated carbon has better adsorption effect on VOCs,while zeolite molecular sieve has more stable treatment performance for VOCs.(3)After adsorption desorption for 10 times,the performance of both adsorbent materials decreased.Zeolite molecular sieve iodine value decreased by 8.91%,specific surface area decreased by 8.53%,total pore volume decreased by 12.07%,micropore pore volume decreased by 8.71%;honeycomb activated carbon iodine value decreased by 31.78%,specific surface area decreased by 31.64%,total pore volume The decrease was 38.26%,and the micropore volume was reduced by38.98%.(4)Paint exhaust gas in addition to paint mist-VOCs wide load regulation-suction and desorption integration-catalytic oxidation pilot test shows that the paint mist removal efficiency can reach 95.3%,VOCs removal efficiency is 96.88%.Shanghai's ship coating exhaust gas is treated by this process.The annual emission reduction of paint fog is 113,300 tons,and the annual emission reduction of VOCs is16,800 tons.