阅读说明：本技术 水泥工业水泥湿法脱硫工艺的石膏脱水系统的改进结构 (Improved structure of gypsum dewatering system of cement wet desulphurization process in cement industry ) 是由 王道斌 于浩波 郑丽君 罗振 王春丽 王爱琴 于 2020-11-30 设计创作，主要内容包括：本发明公开了一种水泥工业水泥湿法脱硫工艺的石膏脱水系统的改进结构；包括脱硫塔、石膏排出泵、旋流器,所述旋流器的底流口连接脱水系统,所述旋流器的溢流口连接脱硫塔,所述脱水系统包括安装在旋流器正下方的文氏管进料装置,旋流器的底流口通过垂直管路连接文氏管进料装置。改进结构取消了真空皮带机、气液分离器、滤布冲洗水泵、真空泵、滤液水箱、滤液水泵等设备,只保留了旋流器,新增文氏管进料装置,且取消了脱硫综合楼；所述旋流器为连续工作,不增加阀门等节流装置。本发明节省了大量脱硫设备及场地空间,降低了一次性投资及运行维护成本,运行更为可靠,系统的操作更简便。(The invention discloses an improved structure of a gypsum dehydration system of a cement wet desulphurization process in the cement industry; the system comprises a desulfurizing tower, a gypsum discharge pump and a swirler, wherein a underflow port of the swirler is connected with a dewatering system, an overflow port of the swirler is connected with the desulfurizing tower, the dewatering system comprises a venturi tube feeding device arranged right below the swirler, and the underflow port of the swirler is connected with the venturi tube feeding device through a vertical pipeline. The improved structure cancels equipment such as a vacuum belt conveyor, a gas-liquid separator, a filter cloth washing water pump, a vacuum pump, a filtrate water tank, a filtrate water pump and the like, only a swirler is reserved, a venturi tube feeding device is added, and a desulfurization comprehensive building is cancelled; the cyclone works continuously without adding throttling devices such as valves and the like. The invention saves a large amount of desulfurization equipment and space, reduces one-time investment and operation maintenance cost, and has more reliable operation and simpler and more convenient system operation.)

1. An improved structure of a gypsum dehydration system of a cement wet desulphurization process in the cement industry; the system comprises a desulfurizing tower, a gypsum discharge pump connected with the desulfurizing tower, a conveying pipeline of the gypsum discharge pump is connected with a swirler, a bottom flow port of the swirler is connected with a dewatering system, an overflow port of the swirler is connected with the desulfurizing tower, and the system is characterized in that the dewatering system comprises a venturi tube feeding device arranged right below the swirler, and the bottom flow port of the swirler is connected with the venturi tube feeding device through a vertical pipeline; the venturi tube feeding device is arranged at the top of the two-section or three-section grate cooler.

2. The improved structure of the gypsum dewatering system for cement wet desulphurization process in cement industry as claimed in claim 1, characterized in that: the venturi feeding device is of an integrated structure consisting of a feeding pipe, a compressed air inlet section, a conical convergence section, a throat section and a conical diffusion section, wherein four tangential air inlets are uniformly distributed in the compressed air inlet section along the circumferential direction; and four air inlets of the venturi feeding device are respectively connected with a compressed air source.

3. The improved structure of gypsum dewatering system for cement wet desulphurization process in cement industry as claimed in claim 1, wherein the inner wall of said venturi feeding device is smooth and the portion contacting with slurry is 2507 stainless steel.

4. The improved structure of the gypsum dewatering system for cement wet desulphurization process in cement industry as claimed in claim 1, characterized in that: a water supply pipeline is connected to the delivery pipeline connecting the gypsum discharge pump and the cyclone.

5. The improved structure of the gypsum dewatering system for the cement industry cement wet desulphurization process according to any one of claims 1 to 4, characterized in that: when the cement production line is a 5000t/d cement production line, the treated flue gas amount is 960000m3/h, the inlet SO2 concentration is 1600mg/Nm3, the feeding amount of a cyclone of a gypsum dehydration system is 30m3/h, and the solid content is 15%; the underflow flow rate of the cyclone is 5.5m3/hr, and the solid content is 45%.

Technical Field

The invention belongs to the technical field of cement industry, and particularly relates to an improved structure of a gypsum dehydration system suitable for a cement wet desulphurization process in the cement industry.

Background

The limestone-gypsum wet desulphurization process is the most widely applied desulphurization process at present and is the most mature and reliable process in operation at present. The gypsum dewatering system is an important component of the process as a subsequent material treatment system of the process. The structural principle of the gypsum dewatering system of the existing cement industry cement wet desulphurization process can be seen in figure 7. As shown in FIG. 7, the gypsum slurry from the gypsum slurry pump of the absorption tower is subjected to a first stage dewatering by a gypsum cyclone. The bottom flow of the cyclone is sent to a vacuum dehydrator for dehydration; the overflow of the cyclone returns to the desulfurizing tower. In the secondary dewatering system, the concentrated gypsum slurry is dewatered in vacuum by a vacuum belt dewaterer (matched with a gas-liquid separator and a vacuum water ring pump), and a filter cloth washing water pump is used for washing the filter cloth of the belt conveyor. Conveying the desulfurized gypsum to cement clinker to be used as retarder; and the filtrate water enters a filtrate water tank and is conveyed to the grate cooler by a filtrate water pump to be used as water spray for cooling so as to ensure the quality of the desulfurized water. The process has the advantages of complex flow, more equipment, large occupied area and high one-time investment and operation and maintenance cost.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides an improved structure of a gypsum dehydration system of a cement wet desulphurization process in the cement industry, which utilizes the existing process in the cement industry to reasonably simplify the process flow of the gypsum dehydration system, reduces corresponding dehydration equipment, saves layout space and greatly increases the operational reliability of the system.

The invention is realized in such a way that the invention is an improved structure of a gypsum dehydration system of a cement wet desulphurization process in the cement industry; the device is characterized in that the dehydration system comprises a venturi tube feeding device arranged right below the cyclone, the underflow port of the cyclone is connected with the venturi tube feeding device through a vertical pipeline, and the venturi tube feeding device is arranged at the top of the two-section or three-section grate cooler.

In the above technical solution, preferably, the venturi feeding device is an integrated structure composed of a feeding pipe, a compressed air inlet section, a conical convergence section, a throat section and a conical diffusion section, wherein four tangential air inlets are uniformly distributed in the compressed air inlet section along the circumferential direction; and four air inlets of the venturi feeding device are respectively connected with a compressed air source.

In the above technical solution, preferably, the inner wall of the venturi feeding device is smooth, and the portion contacting the slurry is made of 2507 stainless steel.

In the above technical solution, preferably, a water supply pipeline is further connected to the delivery pipeline connecting the gypsum discharge pump and the cyclone.

In the above technical scheme, preferably, when the cement production line is a 5000t/d cement production line, the flue gas treatment amount is 960000m under the working condition³H, inlet SO₂The concentration is 1600mg/Nm³The feeding amount of a cyclone of the gypsum dehydration system is 30m3/h, and the solid content is 15%; the underflow flow of the cyclone is 5.5m3/h, and the solid content is 45 percent.

The invention has the advantages and technical effects that:

the improved structure enables a secondary dewatering system (comprising a vacuum belt conveyor, a gas-liquid separator, a filter cloth flushing water pump, a vacuum pump, a filtrate water tank, a filtrate water pump and the like) in the original gypsum dewatering system to be cancelled, and greatly reduces one-time investment. The desulfurization comprehensive building is cancelled, and the layout space and one-time investment of a cement plant are saved. The disposals of the raw gypsum dewatering system are internal digestions of cement plants: the desulfurized gypsum is mixed with cement clinker, and the filtrate water is added into the grate cooler to be used as cooling and cooling water so as to ensure the quality of the desulfurized gypsum. The material treatment of the gypsum dewatering system with the improved structure is the same as the original system in nature (underflow slurry of a cyclone, filtrate water and gypsum in the underflow slurry are mixed into clinker of a grate cooler), the reliability of the system is greatly improved on the premise of ensuring the application of the original gypsum dewatering system, the operation cost (mainly power consumption) and the manual maintenance cost are reduced, and the practicability is high.

Drawings

FIG. 1 is a structural layout of the present invention (front and top views);

FIG. 2 is a top view of the structure of the present invention;

FIG. 3 is a schematic diagram of the structure of the present invention;

FIG. 4 is a schematic view of the venturi feed device of the present invention;

FIG. 5 is a prior art structural layout diagram;

FIG. 6 is a top view of FIG. 5;

fig. 7 is a schematic diagram of a prior art structure.

In the figure, 1, a desulfurizing tower; 2. a gypsum discharge pump; 3. a swirler; 3-1, a bottom flow port; 3-2, an overflow port; 4. a venturi feed device; 4-1, a feeding pipe; 4-2, a compressed air inlet section; 4-3, a conical convergent section; 4-4, a throat section; 4-5, a conical diffusion section; 4-6, a tangential air inlet; 4-7, a compressed air source; 4-8, a water supply pipeline; 5. a grate cooler; 6. a filter cloth washing water pump; 7. a vacuum belt conveyor; 8. a vacuum pump; 9. a filtrate water tank; 10. a filtrate water pump; 11. a gas-liquid separator.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Please refer to fig. 1 to 4; an improved structure of a gypsum dehydration system of a cement wet desulphurization process in the cement industry; the device comprises a desulfurizing tower 1, a gypsum discharge pump 2 connected with the desulfurizing tower, a conveying pipeline of the gypsum discharge pump is connected with a swirler 3, a underflow port 3-1 of the swirler is connected with a venturi tube feeding device 4 through a vertical pipeline, an overflow port 3-2 of the swirler is connected with the desulfurizing tower, the venturi tube feeding device is arranged at the top of a grate cooler 5, and the grate cooler faces to an original rotary kiln of a cement plant at the position of two sections or three sections of the grate cooler; the venturi feeding device 4 is of an integrated structure consisting of a feeding pipe 4-1, a compressed air inlet section 4-2, a conical convergence section 4-3, a throat section 4-4 and a conical diffusion section 4-5, wherein four tangential air inlets 4-6 of DN40 are uniformly distributed on the compressed air inlet section along the circumferential direction; four air inlets of the venturi tube feeding device are respectively connected with compressed air sources 4-7; a water supply pipeline 4-8 is also connected on the conveying pipeline connecting the gypsum discharge pump and the cyclone. The improved structure cancels equipment such as a vacuum belt conveyor, a gas-liquid separator, a filter cloth washing water pump, a vacuum pump, a filtrate water tank, a filtrate water pump and the like, only a swirler is reserved, a venturi tube feeding device is added, and a desulfurization comprehensive building is cancelled; the venturi feeding device is of an integrated structure consisting of a feeding pipe, a compressed air inlet section, a conical convergence section, a throat section and a conical diffusion section, wherein four tangential air inlets are uniformly distributed in the compressed air inlet section along the circumferential direction; four air inlets of the venturi tube feeding device are respectively connected with a compressed air source; the cyclone works continuously without adding throttling devices such as valves and the like.

In the above technical solution, preferably, the venturi feeding device is an integrated structure composed of a feeding pipe, a compressed air inlet section, a conical convergence section, a throat section and a conical diffusion section, wherein four tangential air inlets are uniformly distributed in the compressed air inlet section along the circumferential direction; and four air inlets of the venturi feeding device are respectively connected with a compressed air source.

In the above technical solution, preferably, the inner wall of the venturi feeding device is smooth, and the portion contacting the slurry is made of 2507 stainless steel.

In the above technical solution, preferably, a water supply pipeline is further connected to the delivery pipeline connecting the gypsum discharge pump and the cyclone.

In the technical scheme, preferably, when the cement production line is a 5000t/d cement production line, the treated flue gas amount is 960000m3/h under the working condition, the inlet SO2 concentration is 1600mg/Nm3, the feeding amount of a cyclone of a gypsum dewatering system is 30m3/h, and the solid content is 15%; the underflow flow of the cyclone is 5.5m3/h, and the solid content is 45 percent.

Because the disposals of the original dehydration system are digested inside a cement plant, the desulfurized gypsum can be mixed into cement clinker, and filtrate water can also be added into the grate cooler to be used as cooling water to ensure the desulfurized water quality, the improved dehydration system has no influence on the material balance of the whole cement industry. The improvement saves a large amount of desulfurization equipment and site space, reduces one-time investment and operation and maintenance cost, and is simpler and more convenient to operate.

In the technical scheme, the cyclone needs to work continuously, and throttling devices such as valves and the like are not added due to the fact that the solid content of the slurry at the outlet is high.

Preferably, in the above technical solution, the conveying pipeline between the cyclone and the venturi feeding device must be perpendicular to the ground, that is, the cyclone is fixed right above the venturi; adopts a vertical self-flowing pipeline, and the inner wall of the pipeline needs to be smooth and made of 2507 stainless steel.

In the technical scheme, the venturi tube feeding device is arranged on the top cover of the two-section or three-section grate cooler and is used as a feeding device, and compressed air is added through an air inlet of the venturi tube feeding device: the venturi can generate micro negative pressure in the conical diffusion section, thereby not only preventing the dry and blockage of the slurry outlet caused by the contact of cement clinker with the slurry outlet, but also preventing high-temperature flue gas from entering the slurry jet orifice.

From the above description, the gypsum slurry delivered from the gypsum slurry pump of the absorption tower is first dewatered by the gypsum cyclone, and then directly delivered into the grate cooler by the venturi feeder, and the secondary dewatering system (including the filter cloth washing water pump 6, the vacuum belt conveyor 7, the vacuum pump 8, the filtrate water tank 9, the filtrate water pump 10, the gas-liquid separator 11, and the like) in the original gypsum dewatering system (see fig. 5 to 7) is eliminated. The import of gypsum discharge pump links to each other with desulfurization tower bottom row's thick liquid mouth, and the export passes through the gypsum slurry pipeline and links to each other with the feed inlet of gypsum swirler, and draws cement plant process water pipe to gypsum slurry pipeline all the way for subsequent use. To prevent gypsum slurry from settling and clogging the pipes, the overall arrangement of pipes needs to be from low to high, with no U-shaped or partial down pipes. The gypsum cyclone has two discharge ports, the overflow port is connected with the desulfurizing tower through a slurry pipe, and the underflow port is connected with the feed inlet of the venturi tube feeder. Four tangential air inlets are arranged outside the venturi tube feeder to introduce compressed air, and slurry discharged from a discharge port of the venturi tube is spirally sprayed into the grate cooler.

The working process of the invention is as follows:

the gypsum slurry in the absorption tower is firstly conveyed to a gypsum cyclone through a gypsum slurry discharge pump, the gypsum cyclone continuously works to classify the gypsum slurry and gypsum crystals, the underflow slurry of the cyclone is concentrated to about 50 percent of concentration, and the underflow slurry is conveyed to a venturi feeder through a gypsum underflow distributor; the overflow slurry (concentration about 5%) from the gypsum cyclone is returned to the desulfurization tower. The underflow slurry of the cyclone enters a venturi tube feeding device through a feeding pipe, compressed air is introduced into an air inlet of the venturi tube feeding device, the venturi tube can generate micro negative pressure in a conical diffusion section, and the inside of the grate cooler is in a negative pressure state, so the underflow slurry of the cyclone can be spirally sprayed into the grate cooler. The device not only prevents the blockage of the slurry outlet due to drying and caking of the slurry outlet caused by the contact of cement clinker with the slurry outlet, but also prevents high-temperature flue gas from entering a slurry injection port (cold air entering a venturi tube prevents hot air from entering a slurry injection chamber). The gypsum slurry pipeline is provided with a process water inlet pipe (controlled by a valve) of a cement plant, so that the gypsum cyclone and the venturi feeding device can still continuously work when the gypsum discharge pump is stopped.

Comparative experiments on applicability:

before the improvement:

please refer to fig. 5 to 7; when the cement production line is a 5000t/d cement production line, the wet desulphurization treatment flue gas amount is 960000m under the working condition³H, inlet SO₂The concentration is 1600mg/Nm³The gypsum dewatering system of the original cement industrial limestone-gypsum wet desulphurization process needs the following gypsum dewatering system equipment:

1. cyclone (1 stage): the material is as follows: polyurethane/steel lining polyurethane, feeding amount 30m³H, solid content 15%; underflow flow 5.5m³Hr, solid content 45%;

2. vacuum belt conveyor (1 station): filtration area 9m²The width of the adhesive tape is 1000, the speed of the adhesive tape is 1-9m/min, the vacuum degree is 0.053MPa, the frequency conversion motor and the host computer are 5.5KW, the local system control box is provided, a remote DCS interface is reserved, and the adhesive tape is arranged at a high position; vacuum consumption 3000m³And/hr. A gas-liquid separator, DN1000, made of FRP;

3. water ring vacuum pump (1 stage): the material quality is cast iron, the pressure is 530mbar (abs), the air extraction is 3500m3/h, and the power is 90 KW;

4. filter cloth washing water pump (2 pieces): centrifugal pump, the material: cr30, the flow is 10m3/h, the lift is 70m, and the power is 15 KW;

5. filtrate water pump (2 stages): the material is as follows: cr30, the flow rate is 35m3/h, the lift is 25m, and the power is 15 KW;

6. a filtrate water tank: phi 4000 multiplied by 4000, V is 50m3, and the exterior paint is anticorrosive;

the specific equipment process layout can be seen in fig. 5 and 6.

As can be seen from fig. 5 and 6, the gypsum dewatering system of the limestone-gypsum wet desulphurization process in the cement industry before improvement needs to be equipped with a desulphurization comprehensive building, and the vacuum belt dehydrator is arranged in the topmost floor of the comprehensive building; a vacuum water ring pump and a gas-liquid separator are arranged on the roof; a gypsum storehouse is arranged below the discharge port of the dehydrator for storing gypsum; the vacuum pump and the cyclone are arranged on the roof of the comprehensive building; a filtrate water tank, a filtrate water pump, a filter cloth flushing pump and the like are arranged on the first floor. The whole system has more equipment, larger occupied area and higher one-time investment and operation and maintenance cost.

After improvement

The improved gypsum dewatering system comprises the following equipment:

1. cyclone (1 stage): the material is as follows: polyurethane/steel lining polyurethane, feeding amount 30m³H, solid content 15%; underflow flow rate is 5.5m3/hr, solid content is 45%;

2. venturi feeder (1 stage): 2507 stainless steel, 4 tangential air inlets DN40 are arranged at the throat;

the specific equipment and process layout can be seen in fig. 1.

And (3) comparative summary: it can be seen from the comparison between fig. 1 and fig. 5 that the gypsum dewatering system of the improved cement wet desulphurization process in the cement industry cancels the vacuum belt conveyor, the gas-liquid separator, the filter cloth flushing water pump, the vacuum pump, the filtrate water tank, the filtrate water pump and other equipment, only keeps the cyclone, adds the venturi feeding device, does not need to design a desulphurization comprehensive building, and saves the floor area by about 150 square meters. The one-time investment is greatly reduced, the operation cost (power consumption) and the manual maintenance cost are reduced, and the layout space of a cement plant is saved.

In conclusion, the improved structure enables a secondary dewatering system (comprising a vacuum belt conveyor, a gas-liquid separator, a filter cloth flushing water pump, a vacuum pump, a filtrate water tank, a filtrate water pump and the like) and a desulfurization comprehensive building in the original gypsum dewatering system to be cancelled. The disposals of the raw gypsum dewatering system are internal digestions of cement plants: the desulfurized gypsum is mixed with cement clinker, and the filtrate water is added into the grate cooler to be used as cooling and cooling water so as to ensure the quality of the desulfurized gypsum. The material treatment of the gypsum dewatering system with the improved structure is the same as the original system in nature (underflow slurry of a cyclone, filtrate water and gypsum in the underflow slurry are mixed into clinker of a grate cooler), the reliability of the system is greatly improved on the premise of ensuring the application of the original gypsum dewatering system, and the practicability is high.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.