Ultra-low discharge cement production system and production process

Abstract

The present invention discloses an ultra-low discharge cement production system and production process, including a preheater, dust and saltpeter integrated equipment, an SP waste heat boiler, a high-temperature fan, a first kiln tail chimney, a rotary kiln, a kiln head grate cooler, an AQC waste heat boiler, a kiln head induced draft fan, a raw material mill system, a kiln tail bag dust collector, and a kiln tail induced draft fan; the preheater, the SP waste heat boiler, the high-temperature fan, and the first kiln tail chimney are connected in sequence through a flue, and the dust and saltpeter integrated equipment is installed at the outlet of the preheater or at the outlet of the SP waste heat boiler; the preheater, the rotary kiln, the kiln head grate cooler, the AQC waste heat boiler, the kiln head induced draft fan, the raw material mill system, the kiln tail bag dust collector, the kiln tail induced draft fan, and the second kiln tail chimney are connected in sequence through a flue. Since the present invention leads the flue gas from the kiln head AQC waste heat boiler to the raw material mill system for preheating raw materials, a set of kiln head dust collectors is omitted at the kiln head, saving the investment cost and operation cost of the kiln head dust collector, with lower cost and more energy saving.

Description

Technical Field

[0001] The invention relates to the field of cement production, and in particular to an ultra-low drainage cement production system and production process. Background Art

[0002] The production line for cement production is composed of a series of equipment, such as Figure 1 As shown, the traditional cement production line includes a preheater 1', an SCR denitrification device 2', an SP waste heat boiler 3', a high temperature fan 4', a first kiln tail chimney 5', a rotary kiln 6', a kiln head grate cooler 7', an AQC waste heat boiler 8', a kiln head dust collector 9', a kiln head induced draft fan 10', a raw material grinding system 11', a kiln tail bag dust collector 12', a kiln tail induced draft fan 13', a second kiln tail chimney 14', etc. This production line has the problems of large dust at the kiln tail and NOx emissions not meeting the standards. In addition, three sets of dust removal equipment, including the SCR denitrification device 2', the kiln tail bag dust collector 12', and the kiln head dust collector 9', are used, which have a relatively complex structure and high equipment cost. Summary of the invention

[0003] An object of the present invention is to provide an ultra-low drainage cement production system with simple structure, energy saving and low cost.

[0004] Another object of the present invention is to provide a production process of an ultra-low drainage cement production system with good energy-saving effect.

[0005] To achieve the above purpose, the technical solution of the present invention is:

[0006] The present invention is an ultra-low discharge cement production system, comprising a preheater, dust and saltpeter integrated equipment, an SP waste heat boiler, a high-temperature fan, a first kiln tail chimney, a rotary kiln, a kiln head grate cooler, an AQC waste heat boiler, a kiln head induced draft fan, a raw material grinding system, a kiln tail bag dust collector, and a kiln tail induced draft fan;

[0007] The preheater, SP waste heat boiler, high temperature fan and the first kiln tail chimney are connected in sequence through a flue, and the dust and saltpeter integrated equipment is installed at the outlet of the preheater or at the outlet of the SP waste heat boiler; the preheater, rotary kiln, kiln head grate cooler, AQC waste heat boiler, kiln head induced draft fan, raw material grinding system, kiln tail bag dust collector, kiln tail induced draft fan and the second kiln tail chimney are connected in sequence through a flue.

[0008] The filter element of the dust and saltpeter integrated equipment installed at the outlet of the preheater is composed of a metal filter bag and a catalytic layer.

[0009] The filter element of the dust and saltpeter integrated equipment installed at the outlet of the SP waste heat boiler is composed of a metal filter bag and a catalytic layer or a common chemical fiber filter bag + a catalytic layer or a catalytic filter bag.

[0010] The metal filter bag can be a common cylindrical metal filter bag or a pleated metal filter bag.

[0011] The present invention discloses a production process of an ultra-low emission cement production system. The flue gas discharged from the preheater is dedusted by a dust and nitrate integrated device installed at the outlet of the preheater and then sent to an SP waste heat boiler. The SP waste heat boiler recovers the heat of the flue gas and then is discharged from the first kiln tail chimney through a high-temperature fan. The flue gas discharged from the kiln head is dedusted by an AQC waste heat boiler and then sent to a raw meal grinding system through a kiln head induced draft fan to preheat raw materials. The flue gas after preheating the raw materials is dedusted by a kiln tail bag filter and then is discharged from the second kiln tail chimney through a kiln tail induced draft fan.

[0012] The present invention discloses a production process of an ultra-low emission cement production system. The flue gas discharged from a preheater is sent to an SP waste heat boiler, which recovers the heat of the flue gas. The flue gas from the outlet of the SP waste heat boiler is dedusted by a dust and saltpeter integrated device installed at the outlet of the SP waste heat boiler, and then discharged from a first kiln tail chimney through a high-temperature fan; the flue gas discharged from a kiln head is sent to an AQC waste heat boiler to recover the heat of the flue gas, and then the flue gas is sent to a raw meal grinding system through a kiln head induced draft fan to preheat raw materials. The flue gas after preheating the raw materials is dedusted by a kiln tail bag filter, and then discharged from a second kiln tail chimney through a kiln tail induced draft fan.

[0013] After adopting the above scheme, the present invention has the following advantages:

[0014] (1) The present invention adds a set of integrated dust and nitrate removal equipment at the outlet of the preheater, which solves the ultra-low emission problem of dust and NOx at the kiln tail. The flue gas is directly discharged after heat recovery by the SP waste heat boiler, without having to return to the raw material mill system and the bag dust collector system at the kiln tail for secondary dust removal.

[0015] (2) The present invention introduces the flue gas from the AQC waste heat boiler at the kiln head to the raw meal mill system to preheat the raw meal, thereby eliminating a set of kiln head dust collectors at the kiln head, saving the investment cost and operating cost of the kiln head dust collectors, resulting in lower costs and more energy-saving overall process.

[0016] (3) The kiln tail flue gas of the present invention does not need to be preheated to the raw material after passing through the SP waste heat boiler. The cement plant can improve the waste heat recovery effect of the SP waste heat boiler according to the power generation demand.

[0017] (4) The dust and nitrate integrated equipment of the present invention first removes the dust in the flue gas to within 10 mg / Nm³ through a metal filter bag, and then performs denitrification. The metal filter bag and the catalytic layer are arranged in the same chamber, and the filtering effect is good.

[0018] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the structural diagram of a traditional cement production line;

[0020] Figure 2 is a structural block diagram of a first embodiment of the present invention;

[0021] Figure 3 It is a structural block diagram of the second embodiment of the present invention. Implementation

[0022] 1. Production Line

[0023] like Figure 2 As shown, the present invention is an ultra-low emission cement production system, including a preheater 1, a dust and saltpeter integrated equipment 2, an SP waste heat boiler 3, a high-temperature fan 4, a first kiln tail chimney 5, a rotary kiln 6, a kiln head grate cooler 7, an AQC waste heat boiler 8, a kiln head induced draft fan 9, a raw material grinding system 10, a kiln tail bag dust collector 11, a kiln tail induced draft fan 12, and a second kiln tail chimney 13.

[0024] The first embodiment: the preheater 1, the SP waste heat boiler 3, the high temperature fan 4, and the first kiln tail chimney 5 are connected in sequence through a flue, and the dust and saltpeter integrated equipment 2 is installed at the outlet of the preheater 1; the preheater 1, the rotary kiln 6, the kiln head grate cooler 7, the AQC waste heat boiler 8, the kiln head induced draft fan 9, the raw material grinding system 10, the kiln tail bag dust collector 11, the kiln tail induced draft fan 12, and the second kiln tail chimney 13 are connected in sequence through a flue.

[0025] The filter element of the dust and saltpeter integrated device 2 installed at the outlet of the preheater 1 is composed of a metal filter bag and a catalytic layer.

[0026] The dust and nitrate integrated equipment 2 is the "high-temperature dust removal SCR denitrification integrated device for the cement industry (application number 202220175917.5)" previously applied by the inventor.

[0027] like Figure 3 As shown, the second embodiment: the preheater 1, the SP waste heat boiler 3, the high temperature fan 4, and the first kiln tail chimney 5 are connected in sequence through the flue, and the dust and saltpeter integrated equipment 2 is installed at the outlet of the SP waste heat boiler 3; the preheater 1, the rotary kiln 6, the kiln head grate cooler 7, the AQC waste heat boiler 8, the kiln head induced draft fan 9, the raw material grinding system 10, the kiln tail bag dust collector 11, the kiln tail induced draft fan 12, and the second kiln tail chimney 13 are connected in sequence through the flue.

[0028] The filter element of the dust and saltpeter integrated device 2 installed at the outlet of the SP waste heat boiler 3 is composed of a metal filter bag + a catalytic layer or a common chemical fiber filter bag + a catalytic layer or a catalytic filter bag.

[0029] The present invention can improve the waste heat recovery efficiency of the SP furnace and reduce the flue gas temperature to 150℃~240℃, which is the optimal reaction temperature window of the catalytic filter bag. The catalytic filter bag has the engineering of dust removal and denitrification. After dust removal and denitrification, the dust concentration of the flue gas is ≤10mg / Nm 3 , NOx concentration ≤50mg / Nm 3 , the flue gas can be directly discharged after dust removal and denitrification.

[0030] 2. Production process

[0031] Example 1: Reference Figure 2 The present invention is a production process of an ultra-low emission cement production system. The flue gas discharged from the preheater 1 is sent to the SP waste heat boiler 3 after dust removal by the dust and saltpeter integrated equipment 2 installed at the outlet of the preheater 1. The SP waste heat boiler 3 recovers the heat of the flue gas and is discharged from the first kiln tail chimney 5 through the high-temperature fan 4; the flue gas discharged from the kiln head grate cooler 7 is sent to the AQC waste heat boiler 8 to recover the heat of the flue gas, and the flue gas is then sent to the raw material grinding system 10 through the kiln head induced draft fan 12 to preheat the raw material. The flue gas after preheating the raw material is dusted by the kiln tail bag dust collector 11 and is discharged from the second kiln tail chimney 13 through the kiln tail induced draft fan 12.

[0032] Example 2: Reference Figure 3 The present invention is a production process of an ultra-low emission cement production system according to claim 1, wherein the flue gas discharged from the preheater 1 is sent to the SP waste heat boiler 3, and the SP waste heat boiler 3 recovers the heat of the flue gas. The flue gas discharged from the outlet of the SP waste heat boiler 3 is dedusted by the SCR dust and nitrate integrated device 2 installed at the outlet of the SP waste heat boiler 3, and then discharged from the first kiln tail chimney 5 through the high-temperature fan 4; the flue gas discharged from the kiln head grate cooler 7 is sent to the AQC waste heat boiler 8 to recover the heat of the flue gas, and the flue gas is then sent to the raw meal grinding system 10 through the kiln head induced draft fan 12 to preheat the raw meal. The flue gas after preheating the raw meal is dedusted by the kiln tail bag dust collector 11, and then discharged from the second kiln tail chimney 13 through the kiln tail induced draft fan 12.

[0033] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of implementation of the present invention. That is, equivalent changes and modifications made according to the scope of the patent application of the present invention and the contents of the specification should still fall within the scope covered by the patent of the present invention.

Claims

1. An ultra-low discharge cement production system, characterized in that: Including preheater, dust and saltpeter integrated equipment, SP waste heat boiler, high temperature fan, first kiln tail chimney, rotary kiln, kiln head grate cooler, AQC waste heat boiler, kiln head induced draft fan, raw material grinding system, kiln tail bag dust collector, kiln tail induced draft fan, second kiln tail chimney; The preheater, SP waste heat boiler, high temperature fan, and the first kiln tail chimney are connected in sequence through a flue, and the dust and saltpeter integrated equipment is installed at the outlet of the preheater or at the outlet of the SP waste heat boiler; the preheater, rotary kiln, kiln head grate cooler, AQC waste heat boiler, kiln head induced draft fan, raw material grinding system, kiln tail bag dust collector, kiln tail induced draft fan, and the second kiln tail chimney are connected in sequence through a flue; The core components of the dust and saltpeter integrated equipment installed at the outlet of the preheater are composed of a metal filter bag and a catalytic layer. The filter element of the dust and saltpeter integrated equipment installed at the outlet of the SP waste heat boiler is composed of a metal filter bag + a catalytic layer or a common chemical fiber filter bag and a catalytic layer or a catalytic filter bag.

2. An ultra-low drainage cement production system according to claim 1, characterized in that: The metal filter bag can be a common cylindrical metal filter bag or a pleated metal filter bag.

3. A production process of the ultra-low drainage cement production system according to claim 1, characterized in that: The flue gas discharged from the preheater is dedusted by the integrated dust and saltpeter equipment installed at the outlet of the preheater and then sent to the SP waste heat boiler. The SP waste heat boiler recovers the flue gas heat and is discharged from the first kiln tail chimney through the high-temperature fan; the flue gas discharged from the kiln head is recovered by the AQC waste heat boiler, and the flue gas is then sent to the raw meal grinding system through the kiln head induced draft fan to preheat the raw meal. The flue gas after preheating the raw meal is dedusted by the kiln tail bag dust collector and is discharged from the second kiln tail chimney through the kiln tail induced draft fan.

4. A production process of the ultra-low drainage cement production system according to claim 1, characterized in that: The flue gas discharged from the preheater is sent to the SP waste heat boiler, which recovers the heat of the flue gas. The flue gas discharged from the outlet of the SP waste heat boiler is dedusted by the dust and saltpeter integrated equipment installed at the outlet of the SP waste heat boiler, and then discharged from the first kiln tail chimney through the high-temperature fan; the flue gas discharged from the kiln head is recovered by the AQC waste heat boiler, and the flue gas is then sent to the raw meal grinding system through the kiln head induced draft fan to preheat the raw meal. The flue gas after preheating the raw meal is dedusted by the kiln tail bag dust collector, and then discharged from the second kiln tail chimney through the kiln tail induced draft fan.

Images