A kind of alumina rotary kiln of low NOx drainage
Technical field
The utility model is related to a kind of alumina rotary kilns of low NOx drainage, belong to process for making alumina equipment and technology
Field.
Background technology
In sintering process produces alumina technology, most important process is clinkersintering, the main task of the process be by
What low-grade bauxite, bayer process generated eats mud by being sintered at high temperature into soluble clinker, and then, clinker is by follow-up
Aluminium oxide finished product is made in technique.Main equipment is chamotte kiln in clinkersintering process, in existing chamotte kiln production process, clinker
Sintering temperature reaches 1250 DEG C or more, NOx content >=150mg/m in the flue gas of discharge3, according to《Aluminum i ndustry pollutant emission mark
It is accurate》(GB25465-2010)Specified in alumina producer cure calcining kiln(That is the alumina rotary kiln of the application)NOx emission
Limiting quantity is 100mg/m3, therefore, current chamotte kiln, which is required to additionally to add flue gas processing device, handles tail gas, makes
The limiting value less than national Specification;But the NOx content discharged in chamotte kiln is higher, and the fume treatment added is needed to fill
Set more large-scale, the inorganic agent of addition is also more, and process flow is also longer;Therefore, how to be improved by chamotte kiln, the row of being allowed to
NOx reduction in the flue gas put will greatly reduce the cost and specification of equipment volume of follow-up flue gas processing device.
Utility model content
In order to overcome drawbacks described above, the utility model to provide a kind of alumina rotary kiln of low NOx drainage.
To achieve the goals above, the technical solution of the utility model is:A kind of alumina rotary kiln of low NOx drainage,
Including kiln body, be connected with chamotte cooler below the kiln hood of the kiln body, the kiln tail of kiln body is connected with flue, on the flue with
Kiln tail junction is communicated with backwind tube, and the backwind tube other end is connected with the blast pipe on chamotte cooler, in the backwind tube
Portion is equipped with air-introduced machine.
Preferably, the backwind tube is connected to the blast pipe on chamotte cooler at kiln hood.
Compared with prior art, the beneficial effects of the utility model are:Will in flue containing a large amount of NOx and dust with it is ripe
Cooling air, which is mixed into kiln body, in material cooler carries out second-time burning, and first aspect efficiently uses the big calorimetric in flue gas
Amount reduces energy consumption;Second aspect can ensure that the air quantity in kiln body is enough;NOx in flue gas can be carried out two by the third aspect
Secondary reduction reduces the NOx content being discharged in final flue in flue gas;Through experiment, cigarette is discharged using the chamotte kiln of the application structure
NOx content in gas is less than 80mg/m3。
Description of the drawings
Fig. 1 is the structural schematic diagram of the utility model embodiment 1.
Specific implementation mode
The technical solution of the utility model will be clearly and completely described below, it is clear that described embodiment is
The utility model a part of the embodiment, instead of all the embodiments.Based on the embodiments of the present invention, this field is common
The every other embodiment that technical staff is obtained without making creative work belongs to the utility model protection
Range.
Embodiment 1
The kiln hood lower section of a kind of alumina rotary kiln of low NOx drainage as shown in Figure 1, including kiln body 1, the kiln body 1 connects
It is connected to chamotte cooler 2, the kiln tail of kiln body 1 is connected with flue 3, and backwind tube 4 is communicated with kiln tail junction on the flue 3,
Backwind tube 4 is connected to the blast pipe 201 on chamotte cooler 2 at kiln hood, and 4 middle part of the backwind tube is equipped with air-introduced machine 5.
When actual use, the kiln tail of kiln body 1 is injected into raw slurry, and the high volatilization of 7%-8% is equipped in raw slurry
Part coal dust, backwind tube 4 are sent the partial fume extraction in flue 3 to 2 upper blast pipe 201 of chamotte cooler by air-introduced machine 5
And enter kiln body 1 after being mixed with the air entered in chamotte cooler 2, by rekindling, NOx is in kiln tail and high-volatile
Coal dust carries out secondary reduction reaction and generates N2, it is significantly reduced the NOx content being discharged in flue in flue gas, is allowed to meet national mark
Accurate requirement, has greatly saved the cost for adding follow-up flue gas processing device.
The technical solution of the utility model is not limited to the limitation of above-mentioned specific embodiment, every skill according to the present utility model
The technology deformation that art scheme is made, each falls within the scope of protection of the utility model.