| HCHO is a kind of transparent and irritant organic waste gas. It can dissolve in water and alcohol and ether. It is the effective ingredient of synthetic resin, but it also is toxic pollutant of industrial system.For the past years, the research of purifying formaldehyde waste gas by using biological method has been carried out in foreign countries. Success experiment of abroad has showed that it is effective by using biological method. The biological purifying technology and kinetic model of formaldehyde waste gas is researched by using biological tricking filter. The main results are shown as follows:(1) The results of the effect of the concentration of formaldehyde in influent gas, the gas flow and the liquid flow in purification efficiency of formaldehyde and the biological elimination showed that, when the concentration of formaldehyde in influent gas is rising, the purification efficiency of formaldehyde would be decreased, nevertheless, the biological elimination would be increased. With the increase of thegas flow, the purification efficiency of formaldehyde can be kept at about 65%, but thebiological elimination of formaldehyde would be increased with the rise of the gasflow. When the liquid flow is increased from 10L/h to 20L/h, the purificationefficiency of formaldehyde would be increased from 40% to 80%. When the liquidflow continued to rise, the rising of trend of the purification efficiency offormaldehyde would be decreased. To be exact, when the liquid flow is 40L/h, thepurification efficiency of formaldehyde was about 90%. And the biological eliminationis increased with the increase of the liquid flow. The increase trend of the biologicalelimination would increase when the liquid flow reached 20L/h.(2) The result of biochemical reaction kinetic in biological tricking filter shows that, biochemical degradation reaction of formaldehyde in biofilm is first-order reaction, first-order surface reaction velocity parameter K1=6.911×10-3s-1. The biochemical reaction of formaldehyde is slow-rate. The absorption rate is controlled by slow-rate biochemical reaction. So it must accentuate the rate of biochemical reaction.A kinetic model was established based on "Absorption -Biofilm " theory , the results showed that the interrelation coefficient between calculated data and experimental data of the biological elimination the effluent gas the purificationefficiency of formaldehyde is 0.9549 0.89 0.868 respectively. The correlativity between calculated data and experimental data is good.(3) A kinetic model is established based on "Adsorption -Biofilm " theory the results shows that the interrelation coefficient between calculated data and experimental data of the biological elimination the effluent gas the purification efficiency of formaldehyde is 0.8389 0.6367 0.6427 respectively. The correlativity between calculated data and experimental data was not good.By contrast between two kinds of kinetic model, the results shows that the kinetic model of "Absorption -Biofilm " is better than the kinetic model of "Adsorption -Biofilm ". The kinetic model of "Absorption -Biofilm " could accurately present that the purification process of formaldehyde in biological tricking filter.(4) After fixing the installation of circulation liquid treatment, the results of the effect of the concentration of formaldehyde in influent gas, the gas flow and the liquid flow in purification efficiency of formaldehyde and the biological elimination show that, with the increase of the concentration of formaldehyde in influent gas, the purification efficiency of formaldehyde can be kept at about 93%, but the biological elimination of formaldehyde would be increased. With the increase of the gas flow, the purification efficiency of formaldehyde can be kept at about 99%, but the biological elimination of formaldehyde would be increased. When the liquid flow was rising, the purification efficiency of formaldehyde can be kept at about 96%. When the liquid flow is little than 24L/h, the biological elimination of formaldehyde is rising with the increase of liquid flow. When the liquid flow is bigger than 24L/h, the biological elimination of formaldehyde began to decrease with the increase of liquid flow.(5) By contrast, the purification efficient of formaldehyde after fixing the installation of circulation liquid treatment is better. The biological elimination of formaldehyde is increasing with the increase of the concentration of formaldehyde in influent gas and the increase trend of the biological elimination is about same for two kinds of installation. The biological elimination of formaldehyde would be increased with the rise of the gas flow for two kinds of installation. The biological elimination is kept at 0.40.5mg/(L ? h) with the increase of the liquid flow after fixing the installation of circulation liquid treatment, but the biological elimination is rising with the increase of the liquid flow before fixing the installation of circulation liquidtreatment.The research has proved that it was feasible to purify formaldehyde organic waste gas by using a biological tricking inoculated with microorganism fungus from the item research team. The research provides specific reference and experience of the research and industrial application for purifying formaldehyde organic waste gas by using a biological tricking in china.The research innovations are shown as follows: Firstly, The research has proved that it was feasible to purify formaldehyde waste gas by using a biological tricking inoculated with civil microorganism fungus. Secondly, the research acquires the microorganism fungus for purifying formaldehyde waste gas. Thirdly, the research proves the reaction process and theory. By contrast between two kinds of kinetic model, the results showed that the kinetic model of "Absorption -Biofilm " could accurately present that the purification process of formaldehyde in biological tricking filter. Finally, by contrast the purification efficient of formaldehyde of fixing the installation of circulation liquid treatment to no fixing the installation of circulation liquid treatment. Point out the direction for industrial application.
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