Study Of DZL-type Industrial Bolier's Aerodynamic Field And Boiler Design

Pointing at the present enegy situation and the problems of industrial boiler, this paper gives an analysis and investigation, and put forward that there are two outstanding technological problems in industrial boilers currently, they are low thermal efficiency and high dust concentrations.How to solve the above problems, how to achieve energy saving and discharge decreasing, and how to improve burning efficiency? This is an arduous and urgent task placed in our government and professional technical staff.There are some ways of industrail boiler's enegy saving and discharge decreasing following at moment. Firstly, adding final heating surfaces; secondly, disposing advanced dust catcher; thirdly, improving the configuration of industrial boliler. If the first measures adopted, that is adding tail heating surface, it can improve the boiler's thermal efficiency, but increase the steel consumption, and can't solve the problem of hign dust concentrations, and if exhaust gas temperature is too low will lead to tail heating surfaces corrosion; high dust configuration can reduce dust concentrations and pollutions, therefore, the technology is difficult and the costs is high, and it can't improve the thermal efficiency of boilers. If starting from the furnace structure, combustion can strengthen, not only can improve the boiler's thermal efficieny, but also can reduce the dust concentration of the boiler, it helps energy saving and discharge decreasing.In this paper, starting from the furnace aerodynamic field experiment study, a DZL1.4-0.7/95/70-AⅡ-type hot water boiler is for the experimental equipment. In the cold state using the seven-hole probe we tested the furnace air velocity vector, when the fold smoke wall with an inclination of 0°,30°,45°, then using Lagrange optimization of sub-second difference to divide them, we get the velocity vector of the fold smoke wall angle with 27°to 35°(interval 1°),then use Excel functions to calculate the rotations under different angles of fold smoke wall and the sum of rotation mode of different angles. Input the data to the processing software of Origin, we can get a curve of the sum of rotation model. Finally using MATLAB three-dimensional drawing program to call the value of the furnace air velocity vector, draw the aerodynamic field maps of combustion chamber and reburning chamber with different fold smoke wall angle. Analyzing and comparing the aerodynamic field maps and the sum of rotation models of different angles of the fold smoke wall, we obtain that when the high right low left fold smoke wall to instead of the level wall, and the angel of fold smoke wall is 27°t o 29°, the flue gas disturbed most strongly, and flow the longest line. It's conducive to combustible fly ash's further burning and fly ash's further settlement.Without increasing the cost of steel consumption and other costs in this study, we reduced working hours of industrial boiler's manufacture, and decreased the mechanical incomplete combustion heat loss and chemical incomplete combustion heat loss, increased the boiler thermal efficiency, reduced soot pollution in the atmosphere. It is propitious to boiler's enegy saving and discharge decreasing. The study provides a reference to new boiler's design and old boiler's transformation, and will create considerable economic benefits, social benefits, as well as the environmental benefits.According to the pilot study we designed a DZL1.4-0.7/95/70-AⅠtype hot water boiler and completed the design of the boiler body and body drawings, finished the boiler's strength calculation and thermodynamic calculation Prepared the design specifications, installation instructions, operation instructions. Based on the aerodynamic field stuy, the designed boiler use an inclination of 28°of fold smoke wall, so extended residence time of flue gas in the furnace, made of fly ash from flue gas to further burn-out of fuel. We deployed multi-channel smoke screen wall in concection tube bundles, the smoke had further settlement by centrifugal force and inertia force in convection tube bundles, so reduced the initial industrial boiler dust concentration. Water cycle used the cycle of forced and natural in parallel, both has the advantages of forced circulation and natural cycle,and it can prevent the vaporization of water hammer when power failer, and protected the boiler easily when shutdown. Compared with SZL-type water-tube boiler and DZL-type water-fire tube boiler, this furnace structure would save steel 20%～30%, compared with the industrial boiler's general technical condition, the efficiency of higher than 6.78%.