JP4140828B2 - Cement kiln chlorine / sulfur bypass - Google Patents

Description

【００４７】
一方、ミキシングスクラバー２６に供給される循環スラリーの流路におけるスケールトラブルを防止するためには、循環液槽２７内の循環液のｐＨを４〜６前後に制御する必要がある。そのため、循環液槽２７内の循環液のｐＨが上昇し過ぎた場合には、上述のように、サイクロン２５の分級点を変化させて微粉中のＣａＯ濃度を減少させて対処することができる。また、必要に応じて硫酸貯槽３２に貯蔵される硫酸をポンプ３３を介して循環液槽２７に添加してもよい。
【００４８】
【発明の効果】
以上説明したように、本発明にかかるセメントキルン塩素・硫黄バイパスによれば、塩素バイパスダストを脱塩処理する際の設備コストを低く抑えることができるとともに、セメントキルンの入口フード付近より抽気した燃焼ガスに含まれる硫黄分を除去して有効利用すること等が可能となる。
【図面の簡単な説明】
【図１】本発明にかかるセメントキルン塩素・硫黄バイパスの一実施の形態を示すフロー図である。
【図２】本発明にかかるセメントキルン塩素・硫黄バイパスの一実施例として、湿式集塵装置にミキシングスクラバーを用いた場合を示すフロー図である。
【図３】サイクロンで回収されなかった微粉中のＣａＯを含むセメント原料と、ＫＣｌ等を含む微粉の粒度分布を示すグラフである。
【符号の説明】
１ 処理装置
２ 粗粉・微粉分離装置
３ 湿式集塵装置
４ 分離・水洗装置
５ 排水処理・脱塩装置
６ セメントキルン入口フード
２１ 処理装置
２２ セメントキルン
２３ プローブ
２４ 冷却ファン
２５ サイクロン
２６ ミキシングスクラバー
２７ 循環液槽
２８ 洗浄塔
２９ ポンプ
３０ ファン
３２ 硫酸貯槽
３３ ポンプ
３４ 分離・水洗装置
３５ 排水処理・脱塩装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cement kiln chlorine / sulfur bypass, and in particular, a cement for extracting a part of combustion gas from a kiln exhaust gas passage from the bottom of the kiln to the bottom cyclone and removing chlorine and sulfur. Regarding kiln chlorine / sulfur bypass.
[0002]
[Prior art]
In the past, attention has been paid to the fact that chlorine is a particular problem among chlorine, sulfur, alkali, etc. that cause problems such as clogging of preheaters in cement production facilities. Chlorine bypass equipment is used to bleed out the part to remove chlorine.
[0003]
In this chlorine bypass facility, chlorine is unevenly distributed on the fine powder side of the dust generated by cooling the extracted exhaust gas, so the dust is separated into coarse powder and fine powder by a classifier, and the coarse powder is returned to the cement kiln system. At the same time, fine powder (chlorine bypass dust) containing separated potassium chloride (KCl) and the like was recovered and added to the cement grinding mill system (for example, see Patent Document 1).
[0004]
However, in recent years, recycling of waste by converting it into cement raw material or fuel has been promoted, and as the amount of waste processed increases, the amount of chlorine, sulfur, alkali and other volatile components brought into the cement kiln also increases. The amount of bypass dust is also increasing. For this reason, all of the chlorine bypass dust could not be used in the cement crushing process and was washed with water. However, the amount of chlorine bypass dust generated is expected to increase further in the future, so the development of an effective method for its use is expected. Was demanded.
[0005]
From this point of view, in order to desalinate chlorine bypass dust that has been washed with water and use it effectively as a raw material for cement, water is added to waste containing chlorine and the chlorine in the waste is eluted and filtered. In addition to using the obtained desalted cake as a cement raw material, the wastewater is purified to effectively use chlorine bypass dust without causing environmental pollution (see, for example, Patent Document 2).
[0006]
[Patent Document 1]
International Publication No. WO97 / 21 Pamphlet [Patent Document 2]
Japanese Patent Laid-Open No. 11-100343
[Problems to be solved by the invention]
However, in the cement raw material treatment method described in Patent Document 2 above, chlorine bypass dust is recovered using a cooler (heat exchanger) and a high-temperature bag filter when desalinating chlorine bypass dust and the like. However, because chlorine bypass dust contains salt, the cooler and the like are easily corroded, the life of the equipment is shortened, and the large-capacity tank and quantitative feeder that store a large amount of dust that has a very low bulk specific gravity and is difficult to handle. Etc. are necessary, and there is a problem that the equipment cost increases.
[0008]
In addition, when performing the above-mentioned chlorine bypass, some of the combustion gas extracted from near the inlet hood of the cement kiln contains sulfur, so the extracted gas cannot be discharged out of the system as it is and is attached to the cement kiln. It was necessary to return to a dried raw material or pulverization process.
[0009]
Therefore, the present invention has been made in view of the problems in the conventional method for treating a cement kiln bleed gas, and can reduce the equipment cost. The combustion gas extracted from the vicinity of the inlet hood of the cement kiln can be reduced. The purpose of the present invention is to provide a cement kiln chlorine / sulfur bypass capable of removing contained sulfur and effectively using it.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention is a cement kiln chlorine / sulfur bypass, wherein a part of combustion gas is extracted from a kiln exhaust gas passage from the bottom of the cement kiln to the bottom cyclone. Then, coarse dust dust is extracted from the extraction gas, and the extraction gas containing fine powder is collected using a solvent by a wet dust collector.
[0011]
And according to invention of Claim 1, in order to collect the extraction gas containing a fine powder using a solvent using a wet dust collector, a dust collection slurry is supplied as it is to a wastewater treatment / desalination device or the like. This eliminates the need for water-washing equipment that has been conventionally used when desalinating chlorine bypass dust, thereby reducing equipment costs. As the solvent, a liquid material that can collect dust or the like in the extraction gas, such as water or a slurry containing water, is used. In addition, the extraction gas can be cooled and the chlorine bypass dust can be collected at a time using a wet dust collector, eliminating the need for a cooler and a high-temperature bag filter, which have been required in the past, and a low-capacity chlorine bypass dust. Therefore, the large-scale storage facility that has been necessary in the past is also unnecessary, and the facility cost can be greatly reduced. Furthermore, sulfur dioxide (SO ₂ ) in the combustion gas is reacted with slaked lime (Ca (OH) ₂ ) generated by reacting quick lime (CaO) in the dust fine powder in the extraction gas with water to desulfurize as gypsum. It can be discharged outside the cement kiln system and used effectively in the cement mill.
[0012]
The invention according to claim 2 is the cement kiln chlorine / sulfur bypass according to claim 1, wherein at least a part of the dust collection dust slurry collected by the wet dust collector is added to the cement mill system. Features.
[0013]
According to the second aspect of the present invention, it is possible to treat the dust collection dust slurry in a cement mill system while effectively using gypsum generated during exhaust gas treatment.
[0014]
The invention according to claim 3 is the desalting obtained by solid-liquid separation of the dust collection dust slurry collected by the wet dust collector in the cement kiln chlorine / sulfur bypass according to claim 1 or 2 It is characterized by adding dust cake to the cement mill system.
[0015]
According to the third aspect of the present invention, the gypsum is added by adding to the cement mill system the desalted dust cake obtained by solid-liquid separation of the dust collection dust slurry collected by the wet dust collector and removing the chlorine content. The desalted dust cake containing it can also be used effectively.
[0016]
According to a fourth aspect of the present invention, in the cement kiln chlorine / sulfur bypass according to any one of the first to third aspects, the dust collection dust slurry collected by the wet dust collector is separated into solid and liquid and separated. It is characterized in that at least a part of salt water is added to the cement mill system.
[0017]
According to invention of Claim 4, at least one part of the salt water isolate | separated from the dust collection dust slurry can be processed in a cement mill type | system | group.
[0018]
According to a fifth aspect of the present invention, in the cement kiln chlorine / sulfur bypass according to any one of the first to fourth aspects, the dust-collected dust slurry collected by the wet dust collector is separated into solid and liquid and separated. Salt water is desalted in the salt recovery process to recover industrial salt, and the treated water after desalting is reused as washing water for washing after solid-liquid separation and / or as dust collecting water for the wet dust collector It is characterized by doing.
[0019]
According to invention of Claim 5, while being able to collect | recover industrial salt from the salt water isolate | separated from the dust collection dust slurry, between a waste_water | drain demineralizer and a solid-liquid separator, and / or a wet dust collector, Since water can be recycled, it is possible to reduce the amount of water discharged out of the system as much as possible and to effectively use the water.
[0020]
The invention according to claim 6 is characterized in that, as a preferred form of the cement kiln chlorine / sulfur bypass according to any one of claims 1 to 5, the wet dust collector is a mixing scrubber. Here, the mixing scrubber is characterized in that a plurality of guide vanes that turn the flow in the course of gas and liquid moving countercurrently or in parallel flow in the cylinder. , Refers to a device that brings a gas and a liquid into contact with each other to perform reaction, dust collection, and the like. Preferably, the gas and the liquid are arranged in parallel, and guide vanes that give a right turn to the flow and guide vanes that give a left turn are alternately arranged.
[0021]
A seventh aspect of the present invention is the cement kiln chlorine / sulfur bypass according to the sixth aspect, wherein the mixing scrubber is supplied with a circulating liquid tank to which dust collection dust slurry collected by the mixing scrubber is supplied, and And a circulation device for returning a part of the dust-collecting dust slurry in the circulation liquid tank to the mixing scrubber.
[0022]
According to the seventh aspect of the present invention, since the dust collection dust slurry can be circulated through the mixing scrubber, the dust collection efficiency of the mixing scrubber can be easily adjusted by controlling the circulation rate of the dust collection dust slurry. In addition, it is possible to ensure stable operation of the salt water concentrating device and the crystallizing device in the waste water treatment / desalination device in the subsequent stage.
[0023]
The invention according to claim 8 is the cement kiln chlorine / sulfur bypass according to claim 7 , further comprising a sulfuric acid addition device for adding sulfuric acid to the circulating liquid tank.
[0024]
According to invention of Claim 8, when the pH of the circulating fluid in a circulating fluid tank rises too much, a circulating fluid in a circulating fluid tank is added by adding a sulfuric acid from a sulfuric acid addition apparatus to a circulating fluid tank. By controlling the pH of the mixture to 7 or less, preferably 4 to 6 and converting the generated calcium carbonate to gypsum, scale troubles in the flow path of the circulating slurry supplied to the mixing scrubber can be prevented.
[0025]
A ninth aspect of the present invention is the cement kiln chlorine / sulfur bypass according to any of the sixth to eighth aspects, wherein the combustion is extracted from the kiln exhaust gas flow path from the bottom of the kiln to the bottom cyclone of the cement kiln. A classifier is used to separate the coarse dust of the gas in the gas and obtain an extraction gas containing fine powder, and the classification point of the classifier is variable.
[0026]
According to the invention described in claim 9, by adjusting the classification point of the classifier, the CaO concentration contained in the fine powder is controlled, the pH of the circulating fluid in the circulating fluid tank is controlled, or the sulfur content is absorbed. The desulfurization efficiency can be controlled by increasing the amount of Ca (OH) ₂ as an agent. The classifier includes a dry classifier, that is, a gravity classifier such as a sedimentation chamber, an inertia classifier such as a V type and a zigzag type, a centrifugal classifier such as an air swirl type and a rotary blade type, a vibrating sieve, a sonic sieve, An air flow dispersion type mechanical sieve or the like can be used.
[0027]
A tenth aspect of the present invention is the cement kiln chlorine / sulfur bypass according to any one of the sixth to eighth aspects, wherein the cement kiln is in the combustion gas extracted from the kiln exhaust gas flow path from the bottom of the kiln to the bottom cyclone. A cyclone is used to separate coarse dust of dust and obtain an extraction gas containing fine powder, and the inlet wind speed of the cyclone is variable.
[0028]
According to the invention described in claim 10, by adjusting the classification point by changing the inlet wind speed of the cyclone, the concentration of CaO contained in the fine powder is controlled, and the pH of the circulating fluid in the circulating fluid tank is controlled. The desulfurization efficiency can be controlled by increasing the amount of Ca (OH) ₂ as the sulfur absorbent. The inlet wind speed is changed by changing the position of the guide vane or changing the number of cyclones.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
[0030]
FIG. 1 shows an embodiment of a cement kiln chlorine / sulfur bypass according to the present invention. This processing apparatus 1 is composed of a coarse powder / fine powder separator 2 such as a cyclone, and preferably a mixing scrubber or a venturi scrubber. It comprises a wet dust collecting device 3, a separation / washing device 4 such as a filtration / water washing device, a centrifugal separation device, and a waste water treatment / desalination device 5.
[0031]
The bleed gas from the vicinity of the cement kiln inlet hood 6 is cooled by cold air from a cooling fan in a probe (not shown) and then introduced into the coarse powder / fine powder separation device 2 to be separated into coarse powder, fine powder and gas. The fine powder is collected by the wet dust collector 3 using a solvent. The dust collection slurry containing chlorine such as KCl collected by the wet dust collector 3 is directly added to the cement mill system within a range not exceeding the upper limit of 200 ppm of the chlorine concentration in the cement specified in JIS. be able to. The remaining slurry is washed in the separation / water washing apparatus 4 to remove chlorine, and a desalted dust cake is added to the cement mill system. Thereby, the desalted dust cake containing gypsum can also be used effectively. In addition, the total amount of the dust collection dust slurry collected by the wet dust collection device 3 may be washed by the separation / water washing device 4 to remove chlorine, and the desalted dust cake may be added to the cement mill system.
[0032]
Further, the salt water from the separation / water washing device 4 is supplied to the waste water treatment / desalination device 5 to recover industrial salt, and the waste water can be recycled in the wet dust collector 3 and the separation / water washing device 4. . As is well known, salt water from the separation / washing device 4 may be discharged after removing harmful substances including heavy metals by waste water treatment.
[0033]
On the other hand, the dust collection dust slurry collected by the wet dust collector 3 contains slaked lime (Ca (OH) ₂ ) generated by reaction of quick lime (CaO) in fine powder with water. Therefore, sulfur (SO ₂ ) present in the extracted gas from the cement kiln inlet hood 6 reacts with this slaked lime,
CaO + H ₂ O → Ca (OH) ₂
SO ₂ + Ca (OH) ₂ → CaSO ₃ · 1 / 2H ₂ O + 1 / 2H ₂ O
CaSO ₃ · 1 / 2H ₂ O + 1 / 2O ₂ + 3 / 2H ₂ O → CaSO ₄ · 2H ₂ O
Can be desulfurized to recover gypsum.
[0034]
As described above, the chlorine content containing KCl may be recovered as industrial salt, and the separated salt water is directly attached to the cement kiln within a range not exceeding the upper limit of 200 ppm of chlorine concentration in the cement. It is also possible to process by putting it into a cement mill system.
[0035]
Moreover, in the said Example, although the quicklime in fine powder reacted with water in the dust collection dust slurry collected with the wet dust collector 3, the slaked lime produced | generated was utilized as a slaked lime source from the kiln bottom of a cement kiln. Some or all of the coarse powder separated from the extracted gas extracted from the kiln exhaust gas flow path to the bottom cyclone is reacted with water, the cement kiln calcined raw material is reacted with water, or a separate system Slaked lime from the outside can also be used.
[0036]
Next, as an example of the cement kiln chlorine / sulfur bypass according to the present invention, refer to FIG. 2 for the case where a mixing scrubber 26 (such as a muscrubber manufactured by Mu Company Limited) is used in the wet dust collector 3. While explaining.
[0037]
The treatment device 21 in this embodiment is roughly divided into a cyclone 25 as a coarse / fine powder separation device, a mixing scrubber 26, a circulating liquid tank 27, a washing tower 28, a separation / water washing device 34, a waste water treatment / It consists of a desalinator 35 and the like. A pump 29 for circulating the slurry is provided between the mixing scrubber 26 and the circulating liquid tank 27. In addition, a sulfuric acid storage tank 32 and a pump 33 are arranged to supply sulfuric acid for adjusting the pH of the circulating slurry to the circulating liquid tank 27.
[0038]
Extracted gas from the kiln exhaust gas flow path from the kiln bottom of the cement kiln 22 to the bottom cyclone is cooled by the cool air from the cooling fan 24 at the probe 23 and then introduced into the cyclone 25, where coarse powder, fine powder, and gas are introduced. And separated. The fine powder and gas are cooled in the mixing scrubber 26 by moisture or the like of the slurry supplied from the circulating liquid tank 27, and the fine powder is collected by the mixing scrubber 26. The superficial velocity V (m / s) of the mixing scrubber 26 is preferably 2 ≦ V ≦ 8.
[0039]
Since the exhaust gas discharged from the mixing scrubber 26 is released to the atmosphere through the circulating liquid tank 27, the cleaning tower 28, and the fan 30, it is necessary to increase the dust collection efficiency of the mixing scrubber 26. Therefore, the amount of circulating fluid in the mixing scrubber 26 is increased so that the dust concentration of the exhaust gas discharged to the atmosphere is below a predetermined allowable value. When the dust concentration of the exhaust gas is less than the allowable value, control is performed to gradually reduce the amount of circulating fluid and to reduce the pressure loss and power consumption of the mixing scrubber 26. The ratio γ (l / m ³ ) between the circulating fluid amount and the exhaust gas amount is preferably 15 ≦ γ ≦ 45.
[0040]
Moreover, it is preferable to control the salt concentration of the circulating slurry of the mixing scrubber 26 within a certain range in the operation of the salt water concentrating device and the crystallization device in the waste water treatment / desalination device 35 in the subsequent stage. Therefore, while monitoring the salt water concentration in the circulating liquid tank 27, the discharge amount of the slurry is adjusted so as to be within a certain concentration range, and the addition amount of makeup water is controlled.
[0041]
The dust collecting dust slurry containing chlorine such as KCl collected by the mixing scrubber 26 is separated into cake and salt water in the separation / washing device 34 through the circulating liquid tank 27, and the desalted dust cake is added to the cement mill system. To do. Thereby, the desalted dust cake containing gypsum can be used effectively. Further, the salt water from the separation / water washing device 34 is supplied to the waste water treatment / desalination device 35 to recover industrial salt. When obtaining a salt having a particularly high concentration, the salt water discharged from the separation / water washing device 34 may be returned to the circulating liquid tank 28 and recycled.
[0042]
On the other hand, as described above, in the dust collection dust slurry collected by the mixing scrubber 26, Ca (OH) ₂ generated by the reaction of CaO in the fine powder with water is present, and therefore, from the cement kiln inlet hood. SO ₂ present in the extraction gas reacts with this Ca (OH) ₂ ,
CaO + H ₂ O → Ca (OH) ₂
SO ₂ + Ca (OH) ₂ → CaSO ₃ · 1 / 2H ₂ O + 1 / 2H ₂ O
CaSO ₃ · 1 / 2H ₂ O + 1 / 2O ₂ + 3 / 2H ₂ O → CaSO ₄ · 2H ₂ O
Can be desulfurized to recover gypsum.
[0043]
Here, the effect of removing sulfur contained in the extracted gas is confirmed by monitoring the concentration of sulfur in the exhaust gas, but if the removal performance tends to be reduced, it is necessary to add an absorbent. . To increase Ca (OH) ₂ as an absorbent, the following operation is performed.
[0044]
The particle size distribution of the cement raw material containing CaO in the fine powder not recovered in the cyclone 25 and the fine powder containing KCl or the like is as shown in FIG. Therefore, in order to increase the amount of CaO that functions as an absorbent, the classification point of the cyclone 25 is moved from point A to point B, for example. Thereby, the CaO density | concentration in the fine powder discharged | emitted from the cyclone 25 rises, and the quantity of an absorber can be increased.
[0045]
The separated particle size of the cyclone 25 is determined by the following equation. Where D ₀ : separation particle size [cm], μ: fluid viscosity [poise], ρ _S : dust specific gravity [g / cm ³ ], ρ _f : fluid specific gravity [g / cm ³ ], V _i : inlet flow velocity [cm / sec], d ₀ : outlet duct diameter [cm], H: cyclone hopper height [cm]. Accordingly, when changing the classification point of the cyclone 25, the separation particle diameter D ₀ is increased by decreasing the inlet flow velocity V _i , decreasing the cyclone hopper height H, or decreasing the outlet duct diameter d _0. However, since it is actually difficult to change the cyclone hopper height H and the outlet duct diameter d ₀ , the inlet flow velocity V _i is adjusted by changing the position of the guide vanes and the number of cyclones. Is a realistic policy.
[0046]
[Expression 1]

[0047]
On the other hand, in order to prevent a scale trouble in the flow path of the circulating slurry supplied to the mixing scrubber 26, it is necessary to control the pH of the circulating liquid in the circulating liquid tank 27 to around 4-6. Therefore, when the pH of the circulating fluid in the circulating fluid tank 27 increases too much, as described above, the classification point of the cyclone 25 can be changed to reduce the CaO concentration in the fine powder. Moreover, you may add the sulfuric acid stored in the sulfuric acid storage tank 32 to the circulating liquid tank 27 via the pump 33 as needed.
[0048]
【The invention's effect】
As described above, according to the cement kiln chlorine / sulfur bypass according to the present invention, it is possible to reduce the equipment cost when desalinating the chlorine bypass dust, and the combustion extracted from the vicinity of the inlet hood of the cement kiln. It is possible to effectively use by removing sulfur contained in the gas.
[Brief description of the drawings]
FIG. 1 is a flowchart showing an embodiment of a cement kiln chlorine / sulfur bypass according to the present invention.
FIG. 2 is a flow diagram showing a case where a mixing scrubber is used in a wet dust collector as an example of the cement kiln chlorine / sulfur bypass according to the present invention.
FIG. 3 is a graph showing the particle size distribution of a cement raw material containing CaO in fine powder not recovered by a cyclone and fine powder containing KCl and the like.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Processing apparatus 2 Coarse / fine powder separation apparatus 3 Wet dust collection apparatus 4 Separation / water washing apparatus 5 Waste water treatment / desalination apparatus 6 Cement kiln inlet hood 21 Processing apparatus 22 Cement kiln 23 Probe 24 Cooling fan 25 Cyclone 26 Mixing scrubber 27 Circulation Liquid tank 28 Cleaning tower 29 Pump 30 Fan 32 Sulfuric acid storage tank 33 Pump 34 Separation / washing device 35 Wastewater treatment / desalination device

Claims (10)

Part of the combustion gas is extracted from the kiln exhaust gas flow path from the bottom of the kiln of the cement kiln to the bottom cyclone, coarse dust in the extracted gas is separated, and the extracted gas containing fine powder is removed with a wet dust collector. Cement kiln chlorine / sulfur bypass, characterized by collecting dust using 2. The cement kiln chlorine / sulfur bypass according to claim 1, wherein at least a part of the dust collection dust slurry collected by the wet dust collector is added to a cement mill system. 3. The cement kiln chlorine according to claim 1, wherein the dust collection dust slurry collected by the wet dust collector is subjected to solid-liquid separation, and the obtained desalted dust cake is added to a cement mill system. Sulfur bypass. The dust collection dust slurry collected by the wet dust collector is subjected to solid-liquid separation, and at least a part of the separated salt water is added to the cement mill system. Cement kiln chlorine / sulfur bypass. The collected dust slurry collected by the wet dust collector is solid-liquid separated, and the separated salt water is desalted in a salt recovery step to recover industrial salt, and the treated water after desalting is separated after the solid-liquid separation. The cement kiln chlorine / sulfur bypass according to any one of claims 1 to 4, wherein the cement kiln chlorine / sulfur bypass is reused as cleaning water for cleaning water and / or water for dust collection of the wet dust collector. The cement kiln chlorine / sulfur bypass according to any one of claims 1 to 5, wherein the wet dust collector is a mixing scrubber. The mixing scrubber includes a circulating liquid tank to which dust collection dust slurry collected by the mixing scrubber is supplied, and a circulation device for returning a part of the dust collection dust slurry in the circulating liquid tank to the mixing scrubber. The cement kiln chlorine / sulfur bypass according to claim 6. The cement kiln chlorine / sulfur bypass according to claim 7 , further comprising a sulfuric acid addition device for adding sulfuric acid to the circulating liquid tank. Separating dust coarse powder in the combustion gas extracted from the kiln exhaust gas passage from the kiln bottom of the cement kiln to the bottom cyclone, and using a classifier to obtain the extraction gas containing fine powder, The cement kiln chlorine / sulfur bypass according to any one of claims 6 to 8, wherein the classification point is variable. Separating dust coarse powder in the combustion gas extracted from the kiln exhaust gas passage from the kiln bottom of the cement kiln to the bottom cyclone, and using a cyclone to obtain the extraction gas containing fine powder, the inlet wind speed of the cyclone The cement kiln chlorine / sulfur bypass according to any one of claims 6 to 8, characterized by being variable.

Images