Rational Study Of The Easy Regeneration Of Desulfurization And Denitrification Of High Surface Area Agent Design And Machines

In order to avoid the possible secondary pollution by using calcium-based sorbent in traditional desulfurization technology field, this paper creats a novel desulfurization and denitrification technology using nano titania as a physical adsorbent to take advantage of its supper high surface and porosity. Four aspects were studied for the design and preparation of particle sorbent of nano titanium dioxide, investigation of its properties of desulfurization and denitrification in flue gas in a fixed-bed, its regenerable character, adsorption mechanism and mathematical model of titania sorbent: (1) Four different character's titania adsorbent were prepared by different methods whose pore structure were different each other. It mainly discussed to use sol-gel method to prepare the sorbent under different conditions like calcining temperatures, and characterized the properties of surface and internal pore structure. (2) The experiments of dynamic desulfurization and denitrification for flue gas were proceeded in a fixed-bed set and several factors influencing the adsorbing prosperty were discussed. (3) The regenerable investigations were put forward by heating and acid washing for the titanium dioxide sorbent. (4) The mechanism of adsorption of TiO₂ sorbent for SO₂ and NO_X was discussed. The calculation model of pore size and the fixed-bed adsorption model were presented by density function theory and other mathematical method respectively. The results were compared with the experimental data. There are several results and achievements obtained in this paper: (1) The novel sorbent of titania prepared by sol-gel can remove the SO₂ and NO_X in flue gas simultaneously which was granted an invent patent in China. One gram of TiO₂ sorbent can remove more than 80mg SO₂ and 20mg NO_X. (2) Higher than 200m2/g specific surface area of sorbent can be obtained by sol-gel method. (3) This kind of sorbent has good regenerable property. It can keep rather good adsorption ability after ten times regeneration. The desorption rate can remain over 98% while the total adsorption ability decreased only about 2%. (4) The mechanism of adsorption to remove SO₂ and NO_X was mainly physical adsoprtion. The model of pore size calculation and fixed-bed adsorption were successful to get good accordance with experimental data. In conclusion, there is very great potential to remove SO₂ and NO_X in flue gas by using TiO₂ sorbent. This kind of sorbent can be applied in industry widely if the preparation technology is further developed and pretty photocatalysis property of TiO₂ can be developed to enhance the chemisorption fraction.