CN115193863B - Device and method for dechlorinating fly ash by carbon dioxide-assisted three-stage countercurrent washing - Google Patents
Device and method for dechlorinating fly ash by carbon dioxide-assisted three-stage countercurrent washing Download PDFInfo
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- CN115193863B CN115193863B CN202210597221.6A CN202210597221A CN115193863B CN 115193863 B CN115193863 B CN 115193863B CN 202210597221 A CN202210597221 A CN 202210597221A CN 115193863 B CN115193863 B CN 115193863B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B09—DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
- B09B—DISPOSAL OF SOLID WASTE
- B09B3/00—Destroying solid waste or transforming solid waste into something useful or harmless
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B3/00—Cleaning by methods involving the use or presence of liquid or steam
- B08B3/04—Cleaning involving contact with liquid
- B08B3/10—Cleaning involving contact with liquid with additional treatment of the liquid or of the object being cleaned, e.g. by heat, by electricity or by vibration
- B08B3/102—Cleaning involving contact with liquid with additional treatment of the liquid or of the object being cleaned, e.g. by heat, by electricity or by vibration with means for agitating the liquid
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B09—DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
- B09B—DISPOSAL OF SOLID WASTE
- B09B3/00—Destroying solid waste or transforming solid waste into something useful or harmless
- B09B3/30—Destroying solid waste or transforming solid waste into something useful or harmless involving mechanical treatment
- B09B3/38—Stirring or kneading
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B09—DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
- B09B—DISPOSAL OF SOLID WASTE
- B09B3/00—Destroying solid waste or transforming solid waste into something useful or harmless
- B09B3/70—Chemical treatment, e.g. pH adjustment or oxidation
Abstract
The invention relates to a device and a method for dechlorinating washing fly ash, comprising a three-stage washing tank, wherein the top of a first-stage washing tank is provided with a first-stage feed inlet, a first-stage water inlet and an air outlet; the bottom of the first-stage washing tank is provided with a first-stage water outlet; a first-stage stirring rod is arranged in the first-stage washing tank; the bubbling pipe is horizontally inserted into the bottom of the first-stage washing tank body, bubble holes are formed in the bubbling pipe in the first-stage washing tank body, the bubbling pipe outside the first-stage washing tank body is connected with the anti-overflow pipe, and the other end of the anti-overflow pipe is a carbon dioxide air inlet; the first-stage liquid-solid separation equipment is provided with a first-stage liquid-solid separation equipment inlet, a first-stage liquid-solid separation equipment solid outlet and a first-stage liquid-solid separation equipment liquid outlet; the invention effectively reduces the liquid-solid ratio of the water washing system and reduces the energy consumption in the water washing process by multistage water washing and carbon dioxide assistance.
Description
Technical Field
The invention relates to the field of solid waste treatment, in particular to a water-washing fly ash dechlorination device and a method.
Background
With the gradual increase of the garbage cleaning and transportation capacity of China and the gradual increase of the garbage incineration proportion, the generation amount of the garbage incineration fly ash is also increased year by year. The household garbage incineration fly ash is a dangerous waste identified in a dangerous waste directory, and heavy metals, dioxin and chloride salts in the household garbage incineration fly ash are main reasons for high environmental risks. Meanwhile, in the hazardous waste directory, the fly ash from incineration of the household garbage is subjected to conditional exemption, namely, the fly ash after being treated meets the requirements of pollution control standard of the household garbage landfill (GB 16889), and the fly ash enters the household garbage landfill for landfill, and the landfill disposal process is not managed according to hazardous waste. Therefore, the main means of disposal of the waste incineration fly ash at present is sealing ton bags after chelation stabilization, and finally, the disposal is carried out in a domestic garbage landfill site or in a special fly ash storage area.
Because of the poor long term stability of the fly ash chelating products and the ineffectiveness of the chelating agents to dioxins and chloride salts, chelating landfills are increasingly regarded as being at greater environmental risk and are constantly in need of new land resources. In this context, the utilization of fly ash as a resource is a new direction for fly ash treatment. At present, the main method for recycling the fly ash is that the fly ash enters a cement kiln after water washing and dechlorination, and part of raw materials are replaced to prepare cement. The key point of the method is the link of water washing and dechlorination of fly ash. In the fly ash water washing and dechlorination process, after the water washing filtrate is purified, water is recycled through evaporation and condensation, and salt is separated out on the other hand, so that the evaporation causes high process energy consumption and becomes one of main reasons of high water washing cost. At present, the widely used three-stage countercurrent washing process can control the liquid-solid ratio of the fly ash washing to be 4m 3 About/t, how to further reduce the liquid-solid ratio becomes a difficult problem.
The former research shows that carbon dioxide can promote chlorine dissolution in the process of washing fly ash, and the washing can be performed by using lower liquid-solid ratio under the same dechlorination effect. Some patents utilize the advantages of carbon dioxide bubbling water washing, and design some novel water washing devices and methods, but still have certain problems.
As a patent "a fly ash washing device and method based on carbon dioxide tempering" with publication No. CN112275782a, a single-stage washing device and method are proposed, but the washing device uses paddle bubbling, the structure is complex, and only single-stage washing is performed, and the theoretical effect is inferior to that of multi-stage washing.
As another patent, for example, a new system and method for coupling pulping, washing and carbon neutralization of waste incineration fly ash, which is disclosed in publication No. CN113332927a, is proposed as a system and method for washing fly ash after pressurizing and carbonating water, but the amount of carbon dioxide in the pressurized and carbonated water is relatively fixed, and the alkalinity of the washing liquid is not necessarily sufficiently neutralized, so that the best effect of promoting chlorine dissolution cannot be achieved. The system uses carbon dioxide for decalcification purposes and is not aware of its importance for dechlorination. In addition, the system is only single-stage water washing, and the theoretical effect is inferior to that of multi-stage water washing.
Disclosure of Invention
The invention aims to provide a device and a method for dechlorinating fly ash by three-stage countercurrent washing assisted by carbon dioxide, which can reduce the solid-to-liquid ratio of washing liquid and the evaporation energy consumption of a washing process.
In order to achieve the above object, the invention provides a technical scheme comprising a three-stage water washing tank, wherein
The top of the first-stage water washing tank is provided with a first-stage feed inlet, a first-stage water inlet and an air outlet;
the bottom of the first-stage washing tank is provided with a first-stage water outlet;
a first-stage stirring rod is arranged in the first-stage washing tank;
the bubbling pipe is horizontally inserted into the bottom of the first-stage washing tank body, bubble holes are formed in the bubbling pipe in the first-stage washing tank body, the bubbling pipe outside the first-stage washing tank body is connected with the anti-overflow pipe, and the other end of the anti-overflow pipe is a carbon dioxide air inlet;
the first-stage liquid-solid separation equipment is provided with a first-stage liquid-solid separation equipment inlet, a first-stage liquid-solid separation equipment solid outlet and a first-stage liquid-solid separation equipment liquid outlet;
the inlet of the first-stage liquid-solid separation device is connected with a first-stage water outlet on the first-stage water washing tank;
the top of the second-stage washing tank is provided with a second-stage feed inlet and a second-stage water inlet;
the bottom of the second-stage washing tank is provided with a second-stage water outlet;
a second-stage stirring rod is arranged in the second-stage washing tank;
the second-stage liquid-solid separation equipment is provided with a second-stage liquid-solid separation equipment inlet, a second-stage liquid-solid separation equipment solid outlet and a second-stage liquid-solid separation equipment liquid outlet;
the inlet of the second-stage liquid-solid separation device is connected with a second-stage water outlet on the second-stage water washing tank;
the top of the third-stage washing tank is provided with a third-stage feeding hole and a third-stage water inlet;
the bottom of the third-stage water washing tank is provided with a third-stage water outlet;
a third-stage stirring rod is arranged in the third-stage washing tank;
the third-stage liquid-solid separation equipment is provided with a third-stage liquid-solid separation equipment inlet, a third-stage liquid-solid separation equipment solid outlet and a third-stage liquid-solid separation equipment liquid outlet;
the inlet of the third-stage liquid-solid separation device is connected with a third-stage water outlet on the third-stage water washing tank;
the solid outlet of the first-stage liquid-solid separation device is connected with a second-stage feed inlet on the second-stage washing tank;
the liquid outlet of the second-stage liquid-solid separation device is connected with a first-stage water inlet on the first-stage washing tank;
the solid outlet of the second-stage liquid-solid separation device is connected with a third-stage feed inlet of a third-stage washing tank;
the liquid outlet of the third-stage liquid-solid separation device is connected with a second-stage water inlet on the second-stage washing tank.
Further, the upper part of the first-stage water washing tank is also provided with an exhaust port, the exhaust port is connected with a supercharger, and an outlet of the supercharger is connected with a carbon dioxide air inlet.
Further, the number of the blade layers of the first-stage stirring rod in the first-stage water washing tank is more than or equal to 2, wherein the distance between the bottom blade and the bubbling pipe is 20-40cm.
Further, the height of the carbon dioxide air inlet is more than 30cm higher than the liquid level in the first-stage water washing tank.
Further, the carbon dioxide auxiliary three-stage countercurrent washing fly ash dechlorination device is characterized in that two rows of bubbling holes are formed in a bubbling pipe below a blade of the first-stage stirring rod, the two rows of bubbling holes are respectively formed in a bubbling pipe body, the direction of the orifice is 30-50 degrees below two sides of the bubbling pipe, the gas speed of the bubbling hole is 10-15m/s, the bubbling pipe of the first-stage washing tank is inserted into the first-stage washing tank obliquely downwards, and the downward angle is 30-50 degrees.
Further, the water content of the solids discharged by the first-stage liquid-solid separation equipment, the second-stage liquid-solid separation equipment and the third-stage liquid-solid separation equipment is lower than 40%.
The invention also provides a water washing method of the carbon dioxide auxiliary three-stage countercurrent water washing fly ash dechlorination device, which comprises the following steps:
step 1: a certain amount of fly ash and the washing liquid from the second-stage washing tank are stirred for a period of time in the first-stage washing tank through a first-stage stirring rod, and when the second-stage liquid-solid separation equipment does not have the washing liquid at the initial stage of system starting, a certain amount of water is directly used for replacing the washing liquid from the second-stage liquid-solid separation equipment;
step 2: carbon dioxide enters through a carbon dioxide air inlet, continuously flows into the primary water washing tank for a period of time through foam holes on the bubbling pipe, and continuously and synchronously stirs the primary stirring rod in the period of time;
step 3: discharging the water washing slurry in the first-stage water washing tank into first-stage liquid-solid separation equipment, discharging separated wastewater, and delivering separated water washing ash into a second-stage water washing tank;
step 4: in the second-stage washing tank, the washing ash from the first-stage liquid-solid separation device and the washing liquid from the third-stage liquid-solid separation device are stirred for a period of time through a second-stage stirring rod, and when the third-stage liquid-solid separation device does not have washing liquid at the initial stage of system start-up, a certain amount of water is directly used for replacing the washing liquid from the third-stage liquid-solid separation device;
step 5: discharging the water washing slurry in the second-stage water washing tank into second-stage liquid-solid separation equipment, discharging the separated water washing liquid into the first-stage water washing tank, and delivering the separated water washing ash into a third-stage water washing tank;
step 6: in the third-stage water washing tank, stirring the water washing ash from the second-stage liquid-solid separation equipment and water from a third-stage water inlet for a period of time through a third-stage stirring rod;
step 7: discharging the water washing slurry in the third-stage water washing tank into third-stage liquid-solid separation equipment, discharging the separated water washing liquid into the second-stage water washing tank, and discharging the separated dechlorinated ash.
Further, the step 2 further comprises passing unabsorbed carbon dioxide through an exhaust port and then through a supercharger to re-enter the carbon dioxide inlet, wherein the concentration of the carbon dioxide is more than 40%, and the aeration speed of the carbon dioxide enables the pH value of the water washing liquid filled with the carbon dioxide to reach and be kept between 4 and 6.
Further, the stirring time period refers to the time period for stirring until the chloride ion concentration in the water washing liquid is no longer changed.
Further, the water content of the solids discharged by the first-stage liquid-solid separation equipment, the second-stage liquid-solid separation equipment and the third-stage liquid-solid separation equipment is lower than 40%.
The beneficial effects of the invention are as follows:
1. the carbon dioxide bubbling water washing can effectively reduce the pH of the water washing liquid and promote the decomposition of basic calcium chloride in the fly ash, and the method can improve the solubility of the basic calcium chloride so as to reduce the liquid-solid ratio.
2. Carbon dioxide bubbling water washing can convert calcium hydroxide in the water washing liquid into calcium carbonate for precipitation, and in the traditional water washing process, sodium carbonate is added in the step of purifying filtrate for precipitating calcium hydroxide, and then hydrochloric acid is used for neutralizing the generated sodium hydroxide and excessive sodium carbonate to generate sodium chloride. After the calcium ions are converted into calcium carbonate, the calcium carbonate enters a cement kiln for calcination, and carbon dioxide emission can be generated by carbonate decomposition. Thus, carbon dioxide bubbling water washing can reduce sodium chloride (i.e., waste salts) generated by sodium carbonate addition. Carbon dioxide bubbling water wash can also reduce carbon dioxide emissions resulting from sodium carbonate addition if the carbon dioxide originates from cement kiln flue gas.
3. The carbon dioxide bubbling water washing and the three-stage countercurrent water washing are combined, the advantages of the carbon dioxide bubbling water washing and the three-stage countercurrent water washing are simultaneously exerted, and the solid ratio of the water washing is further reduced.
4. When the fly ash is washed in the first-stage washing tank, the normal washing without bubbling is firstly carried out, and then the bubbling washing is carried out, so that the utilization rate of carbon dioxide is improved, and the working time and the electricity consumption of the supercharger are reduced. The principle is that firstly, the easily-dissolved chloride salt is dissolved by ordinary water washing, the dispersion of the particles of the hardly-dissolved chloride salt is promoted, the surface of the particles of the hardly-dissolved chloride salt contacted with water is increased, and then, when the carbon dioxide bubbling water washing is carried out, the hardly-dissolved chloride salt such as basic calcium chloride is more easily reacted with the carbon dioxide and is decomposed into the easily-dissolved chloride salt. In addition, the ordinary water washing can uniformly disperse calcium hydroxide in water from fly ash into the water washing liquid, which is favorable for the reaction of carbon dioxide and the subsequent bubbling water washing, thereby promoting the decomposition of indissolvable chloride salts such as basic calcium chloride in water.
5. The stirring rod in the first-stage water washing tank is of a multi-layer design, and the distance between the bottom layer and the bubbling pipe is relatively short, so that carbon dioxide bubbles are broken by stirring blades in water, and absorption and reaction of the carbon dioxide bubbles in water washing slurry are promoted. The overflow preventing pipe is designed in front of the bubbling pipe of the first-stage water washing tank, so that fly ash slurry cannot flow backward to the carbon dioxide air inlet in the ordinary water washing process before bubbling water washing. The bubbling pipe of the first-stage water washing tank is designed to bubble obliquely downwards, so that slurry flowing into the bubbling pipe is discharged, and stirring mass transfer between carbon dioxide and water and fly ash can be promoted by using bubbling jet flow.
Drawings
FIG. 1 is a schematic diagram of an apparatus of the present invention;
in the figure: 1-first-stage water washing tank, 1-1-first-stage feed inlet, 1-2-first-stage water inlet, 1-3-first-stage stirring rod, 1-4-carbon dioxide air inlet, 1-5-overflow prevention pipe, 1-6-bubbling pipe, 1-7-exhaust port, 1-8-booster, 1-9-first-stage water outlet and 1-10-first-stage water washing tank body; 2-first-stage liquid-solid separation equipment, 2-1-first-stage liquid-solid separation equipment inlet, 2-2-first-stage liquid-solid separation equipment liquid outlet, and 2-3-first-stage liquid-solid separation equipment solid outlet; the device comprises a 3-second-stage water washing tank, a 3-1-second-stage feed inlet, a 3-2-second-stage water inlet, a 3-3-second-stage stirring rod and a 3-4-second-stage water outlet; 3-5-second-stage water washing tank body; 4-second-stage liquid-solid separation equipment, 4-1-second-stage liquid-solid separation equipment inlet, 4-2-second-stage liquid-solid separation equipment liquid outlet and 4-3-second-stage liquid-solid separation equipment solid outlet; the device comprises a 5-third-stage water washing tank, a 5-1-third-stage feed inlet, a 5-2-third-stage water inlet, a 5-3-third-stage stirring rod and a 5-4-third-stage water outlet; 5-5-third stage washing tank body; the device comprises a 6-third-stage liquid-solid separation device, a 6-1-third-stage liquid-solid separation device inlet, a 6-2-third-stage liquid-solid separation device liquid outlet and a 6-3-third-stage liquid-solid separation device solid outlet.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention discloses a device for dechlorinating fly ash by three-stage countercurrent washing assisted by carbon dioxide, which mainly comprises a three-stage washing tank and three-stage liquid-solid separation equipment as shown in figure 1.
A first-stage washing tank 1, which comprises a first-stage washing tank body 1-10, and:
the first-stage feed inlet 1-1 is arranged at one side of the top of the first-stage water washing tank body 1-10;
the first-stage water inlet 1-2 is arranged at the other side of the top of the first-stage water washing tank body 1-10;
the exhaust port 1-7 is arranged at the upper part of one side of the first-stage water washing tank body 1-10 and is adjacent to the first-stage feed port 1-1;
the top of the first-stage washing tank 1 is also provided with an air outlet;
the first-stage water outlet 1-9 is arranged at the bottom of the other side of the first-stage water washing tank body 1-10;
a first-stage stirring rod 1-3 is arranged in the first-stage washing tank 1;
the bubbling pipe 1-6 is horizontally arranged at the bottom of the first-stage washing tank body 1-10, one end of the bubbling pipe extends into the first-stage washing tank body 1-10, and the other end extends to the outside of the first-stage washing tank body 1-10;
one end of the overflow preventing pipe 1-5 is vertically arranged, and is connected with one end of the bubbling pipe 1-6 extending out of the first-stage washing tank body 1-10, and the other end of the overflow preventing pipe vertically extends upwards to the upper part of the first-stage washing tank body 1-10; the upper end of the anti-overflow pipe 1-5 is provided with a carbon dioxide air inlet 1-4;
a second-stage washing tank 3 comprising a second-stage washing tank body 3-5, and:
the second-stage feed inlet 3-1 is arranged at one side of the top of the second-stage water washing tank body 3-5;
the second-stage water inlet 3-2 is arranged at the other side of the top of the second-stage water washing tank body 3-5;
the second-stage water outlet 3-4 is arranged at the bottom of the other side of the second-stage water washing tank 3-5;
a first-stage stirring rod 3-3 is arranged in the second-stage washing tank 3;
a third stage wash tank 3 comprising a third stage wash tank body 5-5, and:
the third-stage feed inlet 5-1 is arranged at one side of the top of the third-stage washing tank body 5-5;
the third-stage water inlet 5-2 is arranged at the other side of the top of the third-stage water washing tank body 5-5;
the third-stage water outlet 5-4 is arranged at the bottom of the other side of the third-stage water washing tank 5-5;
a first-stage stirring rod 5-3 is arranged in the third-stage washing tank 5;
wherein, the exhaust port 1-7 on the first stage washing tank 1 is connected with the carbon dioxide air inlet 1-4 through the booster 1-8; the first-stage water outlet 1-9 on the first-stage washing tank is connected with the first-stage liquid-solid separation equipment inlet 2-1, and the first-stage liquid-solid separation equipment solid outlet 2-3 is connected with the second-stage feed inlet 3-1 on the second-stage washing tank 3;
the second-stage water outlet 3-4 on the second-stage water washing tank 3 is connected with the inlet 4-1 of the second-stage liquid-solid separation equipment; the liquid outlet 4-2 of the second-stage liquid-solid separation device is connected with the first-stage water inlet 1-2 on the first-stage washing tank 1, and the solid outlet 4-3 of the second-stage liquid-solid separation device is connected with the third-stage feed inlet 5-1 of the third-stage washing tank 5;
a third-stage water outlet 5-4 on the third-stage water washing tank 5 is connected with a third-stage liquid-solid separation equipment inlet 6-1; the liquid outlet 6-2 of the third-stage liquid-solid separation device is connected with the second-stage water inlet 3-2 on the second-stage washing tank 3.
Further, the number of the blade layers of the first-stage stirring rod 1-3 in the first-stage washing tank 1 is more than or equal to 2, wherein the distance between the bottom blade and the bubbling pipe 1-6 is 20-40cm. The stirring rod in the first-stage water washing tank is of a multi-layer design, and the distance between the bottom layer and the bubbling pipe is relatively short, so that carbon dioxide bubbles are broken by stirring blades in water, and absorption and reaction of the carbon dioxide bubbles in water washing slurry are promoted.
Further, the height of the carbon dioxide air inlets 1-4 is more than 30cm higher than the liquid level in the first-stage water washing tank 1. The overflow preventing pipe is designed in front of the bubbling pipe of the first-stage water washing tank, so that fly ash slurry cannot flow backward to the carbon dioxide air inlet in the ordinary water washing process before bubbling water washing.
Further, two rows of bubbling holes are arranged on the bubbling pipe below the blades of the first-stage stirring rod 1-3, the two rows of bubbling holes are respectively positioned on the bubbling pipe body, the orifice direction is 30-50 degrees below the two sides of the bubbling pipe, and the bubbling hole air speed is 10-15m/s. The bubbling pipe 1-6 of the first stage washing tank is inserted into the first stage washing tank 1 obliquely downwards, and the downward angle is 30-50 degrees. The downward insertion of the slurry into the bubbling pipe is favorable for the discharge of slurry, and bubbling jet flow can be used for promoting the stirring mass transfer between carbon dioxide and water and fly ash.
Further, the water content of the solids discharged by the first-stage liquid-solid separation device 2, the second-stage liquid-solid separation device 4 and the third-stage liquid-solid separation device 6 is lower than 40%. The water content of the solid discharged by the liquid-solid separation equipment is lower than 40%, which is favorable for reducing the residual chlorine in the water-washed ash.
The working method of the device is as follows:
a certain amount of fly ash enters the first-stage washing tank 1 through the first-stage feed inlet 1-1, the effluent of the second-stage liquid-solid separation equipment 4 enters the first-stage washing tank 1 through the first-stage water inlet 1-2, and stirring and washing are carried out for 15min by using the first-stage stirring rod 1-3, so that the concentration of chloride ions in the washing liquid tends to be stable, wherein the stirring rod is formed by two layers of paddles, the two layers of paddles are arranged, and the minimum distance between the bottom paddles above the bubbling pipe 1-6 is 30cm; then, 80% carbon dioxide was continuously introduced while stirring and washing, so that the pH of the washing liquid was maintained at 4 to 6. 80% concentration carbon dioxide passes through a carbon dioxide air inlet 1-4 (40 cm higher than the liquid level in the first-stage water washing tank 1), passes through an anti-overflow pipe 1-5, enters a bubbling pipe 1-6 (a bubbling hole is arranged on a bubbling pipe body, the direction of an orifice is 45 degrees below the bubbling pipe, the air speed of the bubbling hole is 15 m/s), and unabsorbed carbon dioxide passes through an air outlet 1-7, passes through a continuously working booster compressor 1-8, and reenters the carbon dioxide air inlet 1-4, and is bubbled and stirred for washing for 20min; the concentration of chloride ions in the washing liquid tends to be stable, then bubbling stirring water washing is stopped, washing slurry enters the first-stage liquid-solid separation equipment 2 through the first-stage water outlet 1-9, the washing fly ash is dehydrated, the discharged water is waste water, and the further treatment of steps such as filtrate purification and the like is needed.
The first-stage washing ash dehydrated by the first-stage liquid-solid separation equipment 2 enters the second-stage washing tank 3 through the second-stage feed inlet 3-1, the effluent of the third-stage liquid-solid separation equipment 6 enters the second-stage washing tank 3 through the second-stage water inlet 3-2, and the second-stage stirring rod 3-3 is used for stirring and washing for 15min, so that the concentration of chloride ions in the washing liquid tends to be stable; and then stopping stirring and washing, and enabling the washing slurry to enter the second-stage liquid-solid separation equipment 4 through the second-stage water outlet 3-4 to dehydrate the washing fly ash.
The second-stage water washing ash dehydrated by the second-stage liquid-solid separation equipment 4 enters a third-stage water washing tank 5 through a third-stage feed inlet 5-1, tap water is added according to a certain liquid-solid ratio according to the amount of the fly ash put in by the first stage, the tap water enters the third-stage water washing tank 5 through a third-stage water inlet 5-2, and stirring and water washing are carried out for 10min by using a third-stage stirring rod 5-3, so that the concentration of chloride ions in the water washing liquid tends to be stable; and then stopping stirring and washing, and enabling the washing slurry to enter a third-stage liquid-solid separation device 6 through a third-stage water outlet 5-4 to dehydrate washing fly ash to obtain dechlorinated ash.
Finally, it should be noted that: the foregoing description is only illustrative of the preferred embodiments of the present invention, and although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described, or equivalents may be substituted for elements thereof, and any modifications, equivalents, improvements or changes may be made without departing from the spirit and principles of the present invention.
Claims (10)
1. The device is characterized by comprising a three-stage washing tank, wherein
The top of the first-stage water washing tank (1) is provided with a first-stage feed inlet (1-1), a first-stage water inlet (1-2) and an air outlet;
the bottom of the first-stage water washing tank (1) is provided with a first-stage water outlet (1-9);
a first-stage stirring rod (1-3) is arranged in the first-stage washing tank (1);
the bubbling pipe (1-6) is horizontally inserted into the bottom of the first-stage washing tank body (1-10), bubble holes are formed in the bubbling pipe (1-6) in the first-stage washing tank body (1-10), the bubbling pipe (1-6) outside the first-stage washing tank body (1-10) is connected with the anti-overflow pipe (1-5), and the other end of the anti-overflow pipe (1-5) is provided with a carbon dioxide air inlet (1-4);
the first-stage liquid-solid separation equipment (2) is provided with a first-stage liquid-solid separation equipment inlet (2-1), a first-stage liquid-solid separation equipment solid outlet (2-3) and a first-stage liquid-solid separation equipment liquid outlet (2-2);
the inlet (2-1) of the first-stage liquid-solid separation device is connected with a first-stage water outlet (1-9) on the first-stage water washing tank (1);
the top of the second-stage washing tank (3) is provided with a second-stage feed inlet (3-1) and a second-stage water inlet (3-2);
the bottom of the second-stage water washing tank (3) is provided with a second-stage water outlet (3-4);
a second-stage stirring rod (3-3) is arranged inside the second-stage washing tank (3);
the second-stage liquid-solid separation equipment (4) is provided with a second-stage liquid-solid separation equipment inlet (4-1), a second-stage liquid-solid separation equipment solid outlet (4-3) and a second-stage liquid-solid separation equipment liquid outlet (4-2);
the inlet (4-1) of the second-stage liquid-solid separation device is connected with a second-stage water outlet (3-4) on the second-stage water washing tank (3);
the top of the third-stage rinsing tank (5) is provided with a third-stage feed inlet (5-1) and a third-stage water inlet (5-2);
a third-stage water outlet (5-4) is arranged at the bottom of the third-stage water washing tank (5);
a third-stage stirring rod (5-3) is arranged in the third-stage washing tank (5);
the third-stage liquid-solid separation equipment (6) is provided with a third-stage liquid-solid separation equipment inlet (6-1), a third-stage liquid-solid separation equipment solid outlet (6-3) and a third-stage liquid-solid separation equipment liquid outlet (6-2);
an inlet (6-1) of the third-stage liquid-solid separation device is connected with a third-stage water outlet (5-4) on the third-stage water washing tank (5);
the solid outlet (2-3) of the first-stage liquid-solid separation device is connected with a second-stage feed inlet (3-1) on the second-stage washing tank (3);
the liquid outlet (4-2) of the second-stage liquid-solid separation device is connected with a first-stage water inlet (1-2) on the first-stage water washing tank (1);
the solid outlet (4-3) of the second-stage liquid-solid separation device is connected with a third-stage feed inlet (5-1) of a third-stage washing tank (5);
the liquid outlet (6-2) of the third-stage liquid-solid separation device is connected with a second-stage water inlet (3-2) on the second-stage water washing tank (3).
2. The carbon dioxide-assisted three-stage countercurrent washing fly ash dechlorination device is characterized in that an exhaust port (1-7) is further arranged at the upper part of the first-stage washing tank (1), a supercharger (1-8) is connected to the exhaust port (1-7), and an outlet of the supercharger (1-8) is connected with a carbon dioxide air inlet (1-4).
3. The carbon dioxide-assisted three-stage countercurrent washing fly ash dechlorination device is characterized in that the number of the blade layers of a first-stage stirring rod (1-3) in the first-stage washing tank (1) is more than or equal to 2, and the distance between the bottom blade and a bubbling pipe (1-6) is 20-40cm.
4. The carbon dioxide-assisted three-stage countercurrent washing fly ash dechlorination device according to claim 1, characterized in that the height of the carbon dioxide air inlet (1-4) is more than 30cm higher than the liquid level in the first stage washing tank (1).
5. The carbon dioxide-assisted three-stage countercurrent washing fly ash dechlorination device is characterized in that two rows of bubbling holes are formed in a bubbling pipe (1-6) at the position below a blade of a first-stage stirring rod (1-3), the two rows of bubbling holes are respectively formed in a bubbling pipe body, the orifice direction is that the two sides of the bubbling pipe (1-6) are obliquely downwards 30-50 degrees, the bubbling hole air speed is 10-15m/s, the bubbling pipe (1-6) of the first-stage washing tank (1) is obliquely downwards inserted into the first-stage washing tank (1), and the downward angle is 30-50 degrees.
6. The carbon dioxide-assisted three-stage countercurrent washing fly ash dechlorination device according to claim 1, wherein the water content of solids discharged by the first-stage liquid-solid separation equipment (2), the second-stage liquid-solid separation equipment (4) and the third-stage liquid-solid separation equipment (6) is lower than 40%.
7. A water washing method based on the carbon dioxide-assisted three-stage countercurrent water washing fly ash dechlorination device as claimed in any one of claims 1 to 6, characterized by comprising the following steps:
step 1: a certain amount of fly ash and the water washing liquid from the second-stage liquid-solid separation equipment (4) are stirred for a period of time in the first-stage water washing tank (1) through the first-stage stirring rod (1-3), and when the second-stage liquid-solid separation equipment (4) does not have the water washing liquid at the initial stage of system start-up, a certain amount of water is directly used for replacing the water washing liquid from the second-stage liquid-solid separation equipment (4);
step 2: carbon dioxide enters through a carbon dioxide air inlet (1-4), continuously flows into the first-stage washing tank (1) for a period of time through bubble holes on the bubbling pipe (1-6), and continuously and synchronously agitates the first-stage stirring rod (1-3) in the period of time;
step 3: discharging the water washing slurry in the first-stage water washing tank (1) into first-stage liquid-solid separation equipment (2), discharging separated wastewater, and delivering separated water washing ash into a second-stage water washing tank (3);
step 4: in the second-stage washing tank (3), the washing ash from the first-stage liquid-solid separation equipment (2) and the washing liquid from the third-stage liquid-solid separation equipment (6) are stirred for a period of time through a second-stage stirring rod (3-3), and when the third-stage liquid-solid separation equipment (6) does not have washing liquid at the initial stage of system starting, a certain amount of water is directly used for replacing the washing liquid from the third-stage liquid-solid separation equipment (6);
step 5: discharging the water washing slurry in the second-stage water washing tank (3) into second-stage liquid-solid separation equipment (4), discharging the separated water washing liquid into the first-stage water washing tank (1), and delivering the separated water washing ash into a third-stage water washing tank (5);
step 6: in the third-stage washing tank (5), the washing ash from the second-stage liquid-solid separation equipment (4) and the water from the third-stage water inlet (5-2) are stirred for a period of time through a third-stage stirring rod (5-3);
step 7: the water washing slurry in the third-stage water washing tank (5) is discharged into a third-stage liquid-solid separation device (6), the separated water washing liquid is discharged into a second-stage water washing tank (3), and the separated dechlorinated ash is discharged.
8. The method for washing the fly ash dechlorinating device by three-stage countercurrent washing with carbon dioxide according to claim 7, wherein the step 2 is characterized in that unabsorbed carbon dioxide passes through an exhaust port (1-7) and then passes through a booster (1-8) to enter the carbon dioxide inlet (1-4) again, the concentration of the carbon dioxide is more than 40%, and the aeration speed of the carbon dioxide enables the pH value of the washing liquid when the carbon dioxide is filled to be reached and kept between 4 and 6.
9. The method for washing a carbon dioxide-assisted three-stage countercurrent washing fly ash dechlorination apparatus according to claim 7, wherein the period of stirring is the time taken for the concentration of chloride ions in the washing liquid to be no longer changed.
10. The water washing method of the carbon dioxide-assisted three-stage countercurrent water washing fly ash dechlorination device is characterized in that the water content of solids discharged by the first-stage liquid-solid separation equipment (2), the second-stage liquid-solid separation equipment (4) and the third-stage liquid-solid separation equipment (6) is lower than 40%.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010082487A (en) * | 2008-09-03 | 2010-04-15 | Mitsubishi Heavy Industries Environment & Chemical Engineering Co Ltd | Method and system for washing incineration ash with water |
| CN203803132U (en) * | 2014-03-13 | 2014-09-03 | 天津金恒伟创科技有限公司 | Combined solvent deacidification, dechlorination and deamination equipment |
| CN104529011A (en) * | 2015-01-05 | 2015-04-22 | 北京建筑材料科学研究总院有限公司 | Device and method for reducing hardness and pH value of waste incineration fly ash washing liquid |
| CN107522215A (en) * | 2017-08-14 | 2017-12-29 | 四川大学 | A kind of method of chloride titanium slag dechlorination, mineralization of carbon dioxide coproduction titanium white and ammonia-alum |
| JP2018047395A (en) * | 2016-09-20 | 2018-03-29 | 日立造船株式会社 | Exhaust gas treatment apparatus, garbage incineration facility, and exhaust gas treatment method |
| CN111974786A (en) * | 2020-08-29 | 2020-11-24 | 南京师范大学 | Device and method for reverse washing and efficient dechlorination of waste incineration fly ash of grate furnace |
| CN112275782A (en) * | 2020-10-30 | 2021-01-29 | 南京师范大学 | Fly ash washing device and method based on carbon dioxide tempering |
| CN113633921A (en) * | 2021-09-08 | 2021-11-12 | 宜辰荣(浙江宁波)环境工程技术有限公司 | Fly ash dechlorination method |
| CN113953311A (en) * | 2021-08-31 | 2022-01-21 | 江西盖亚环保科技有限公司 | Fly ash washing process for carbon dioxide modified multistage reverse pulping |
-
2022
- 2022-05-30 CN CN202210597221.6A patent/CN115193863B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010082487A (en) * | 2008-09-03 | 2010-04-15 | Mitsubishi Heavy Industries Environment & Chemical Engineering Co Ltd | Method and system for washing incineration ash with water |
| CN203803132U (en) * | 2014-03-13 | 2014-09-03 | 天津金恒伟创科技有限公司 | Combined solvent deacidification, dechlorination and deamination equipment |
| CN104529011A (en) * | 2015-01-05 | 2015-04-22 | 北京建筑材料科学研究总院有限公司 | Device and method for reducing hardness and pH value of waste incineration fly ash washing liquid |
| JP2018047395A (en) * | 2016-09-20 | 2018-03-29 | 日立造船株式会社 | Exhaust gas treatment apparatus, garbage incineration facility, and exhaust gas treatment method |
| CN107522215A (en) * | 2017-08-14 | 2017-12-29 | 四川大学 | A kind of method of chloride titanium slag dechlorination, mineralization of carbon dioxide coproduction titanium white and ammonia-alum |
| CN111974786A (en) * | 2020-08-29 | 2020-11-24 | 南京师范大学 | Device and method for reverse washing and efficient dechlorination of waste incineration fly ash of grate furnace |
| CN112275782A (en) * | 2020-10-30 | 2021-01-29 | 南京师范大学 | Fly ash washing device and method based on carbon dioxide tempering |
| CN113953311A (en) * | 2021-08-31 | 2022-01-21 | 江西盖亚环保科技有限公司 | Fly ash washing process for carbon dioxide modified multistage reverse pulping |
| CN113633921A (en) * | 2021-09-08 | 2021-11-12 | 宜辰荣(浙江宁波)环境工程技术有限公司 | Fly ash dechlorination method |
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