A bypassed blowdown ash water washing system

Abstract

The utility model discloses a bypass ash washing system, including the solid -liquid separation of the mortar containing bypass windproof ash to the water washing filter press, the output of water washing filter press connects the filtrate tank, and water washing filter press and primary water washing jar, secondary water washing jar, clean water jar constitute two -stage circulating waterway, and the water in primary water washing jar enters water washing filter press and is washed and then carries out in the mortar preparation equipment, and the water in secondary water washing jar enters water washing filter press and is washed and then enters primary water washing jar, and the water in clean water jar enters water washing filter press and is washed and then enters secondary water washing jar, and filtrate tank, clean water jar, primary water washing jar, secondary water washing jar all with water washing filter press between through solenoid valve control waterway on -off. The utility model discloses through the closed type operation technology of whole process to eliminate the toxic and corrosive of bypass ash, and the process satisfies the premise of the reduction, the resource, the harmlessness through washing and removes the chlorides, realizes the wastewater zero discharge and the resource utilization.

Description

Technical Field

[0001] This utility model relates to the field of packaging cleaning technology, specifically to a bypass ventilation and ash water washing system. Background Technology

[0002] Co-processing in cement kilns has become an important method for disposing of solid waste such as municipal solid waste, sludge, and hazardous waste. However, due to the complex composition of solid waste, co-processing solid waste in cement kilns can lead to an increase in the content of alkali, chlorine, and sulfur within the kiln, which then circulates and accumulates, easily causing problems such as kiln crusting and blockage, as well as the formation of cored material and large aggregate balls. To prevent the circulation and accumulation of alkali, chlorine, and sulfur in the kiln system, cement companies need to adopt bypass ventilation technology to release a portion of the flue gas enriched with high concentrations of alkali, chlorine, and sulfur from the kiln tail flue to alleviate this problem. Bypass ventilation systems have gradually become standard equipment in cement kilns that co-process solid waste, and the disposal of bypass vent ash containing high concentrations of alkali, chlorine, and sulfur released by these systems has also become increasingly prominent. The most common method for treating and disposing of bypass vent ash from cement kilns is to grind the bypass vent ash with cement clinker to prepare cement. However, the chloride ion concentration in the bypass vent ash is too high. To ensure that the chloride ion concentration in the cement product meets the quality standards, the amount of bypass vent ash added is subject to significant restrictions. This technology cannot effectively treat all bypass vent ash. Therefore, a water washing technology that can treat bypass vent ash with high chloride ion concentration is needed. Utility Model Content

[0003] Therefore, this utility model provides a bypass venting and ash washing system to solve the problem of unqualified emissions caused by poor filtration quality in the prior art.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A bypass ventilation ash washing system includes a water-washing filter press for solid-liquid separation of ash slurry containing bypass ventilation ash. The output end of the water-washing filter press is connected to a filtrate tank. The water-washing filter press, a primary water-washing tank, a secondary water-washing tank, and a clean water tank form a two-stage circulating water circuit. Water from the primary water-washing tank enters the water-washing filter press for washing and then enters the ash slurry preparation equipment. Water from the secondary water-washing tank enters the water-washing filter press for washing and then enters the primary water-washing tank. Water from the clean water tank enters the water-washing filter press for washing and then enters the secondary water-washing tank. The filtrate tank, clean water tank, primary water-washing tank, and secondary water-washing tank are all connected to the water-washing filter press by solenoid valves to control the water circuit flow.

[0006] Furthermore, the water washing filter press can be connected to a secondary or higher water washing tank. Water from the secondary or higher water washing tank enters the water washing filter press for washing and then enters the secondary water washing tank. Water from the clean water tank enters the water washing filter press for washing and then enters the secondary or higher water washing tank.

[0007] Furthermore, the input end of the water washing filter press is connected to the main input water circuit, and the output ends of the secondary water washing tank and the clear water tank are both connected to the main input water circuit through branch input water circuits; the output end of the water washing filter press is connected to the main output water circuit, and the input ends of the primary water washing tank and the secondary water washing tank are both connected to the main output water circuit through branch output water circuits.

[0008] Furthermore, the feed end of the water washing filter press is connected to a pulping tank, the input end of the pulping tank is connected to a mixing tank, the input end of the mixing tank is connected to a metering tank and a water measuring tank respectively, and the input end of the metering tank is connected to a feeding device for bypassing wind ash.

[0009] Furthermore, the input end of the measuring water tank is connected to a washing tank or a clean water tank.

[0010] Furthermore, an intermediate tank is provided between the water washing filter press and the primary water washing tank, secondary water washing tank, and clean water tank for transition. The output ends of the primary water washing tank, secondary water washing tank, and clean water tank are all connected to the input end of the intermediate tank, and the output end of the intermediate tank is connected to the input end of the water washing filter press; or, the output end of the water washing filter press is connected to the input end of the intermediate tank, and the output end of the intermediate tank is connected to the input ends of the primary water washing tank, secondary water washing tank, and clean water tank, respectively.

[0011] This utility model has the following advantages:

[0012] This utility model discloses a bypass venting ash washing system that eliminates the toxicity and corrosiveness of bypass venting ash through a fully closed-loop operation process. The process design fully considers fully automated control, reducing hazards and labor intensity. Moreover, the bypass venting ash pollutant removal route is clear, with no wastewater discharge, fully realizing the requirements of automation, harmlessness, resource utilization, and zero discharge. Under the premise of meeting the requirements of volume reduction, resource utilization, and harmlessness, the process removes chloride salts through water washing, achieving zero wastewater discharge and resource utilization. Attached Figure Description

[0013] To more clearly illustrate the embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0014] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that this utility model can produce, should still fall within the scope of the technical content disclosed in this utility model.

[0015] Figure 1 A system structure diagram of a bypass ventilation and ash washing system provided for an embodiment of this utility model;

[0016] Figure 2 A system structure diagram of another bypass ventilation ash washing system provided for an embodiment of this utility model.

[0017] In the picture:

[0018] 1. Feeding device; 2. Metering tank; 3. Water measuring tank; 4. Mixing tank; 5. Pulping tank; 6. Water washing filter press; 7. Primary water washing tank; 8. Secondary water washing tank; 9. Clean water tank; 10. Filtrate tank; 11. Horizontal pipe; 12. Intermediate tank. Detailed Implementation

[0019] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0020] like Figure 1 As shown, a bypass ventilation ash washing system includes a water washing filter press 6 for solid-liquid separation of slurry containing bypass ventilation ash. For example, the slurry is pumped to a vertical filter press for solid-liquid separation. The primary filtrate after separation is temporarily stored in a filtrate tank 10 for subsequent processing. This step is not related to the water washing process of this technology, so it will not be described in detail.

[0021] The preparation of the mortar includes a feeding device 1 for placing bypass windbreak ash, the feeding device 1 being connected to a metering tank 2, and both the metering tank 2 and the water measuring tank 3 being connected to a mixing tank 4. The metering tank 2 measures the bypass windbreak ash and then feeds it into the mixing tank 4. Based on the amount of ash fed into the metering tank 2, the water measuring tank 3 calculates the corresponding water ratio and feeds it into the mixing tank 4. The water in the water measuring tank 3 can be sourced from clean water or filtered water from a vertical filter press. The input end of the water measuring tank 3 is connected to a washing tank or a clean water tank 9. It is preferable to use filtered water from a vertical filter press for mixing, which can save water. In this embodiment, the output end of the water measuring tank 3 is connected to the output end of a primary washing tank 7.

[0022] In mixing tank 4, dry powdered bypass windbreak ash is premixed with some or all of the mixing water to obtain a moist, loose mixture that has not yet formed strong cohesion, similar to "wet sand," which is the premixed material. This step is used to wet the dry powder, greatly reducing the dust generated during subsequent high-speed pulping, improving the working environment, providing a relatively uniform wet material base for subsequent high-shear pulping, preventing dry powder clumps from directly entering the high-shear zone, improving pulping efficiency, reducing viscosity impact, and preventing a large amount of dry powder from instantly entering the high-shear equipment, which would cause a sharp increase in viscosity and excessive equipment load.

[0023] In this process, mixing tank 4 uses a high-speed mixer, such as a planetary mixer or a paddle mixer, which has a high mixing speed and a large shear force. The mixing time in the premixing step is relatively short, generally from 30 seconds to 2 minutes, until the mixture is basically free of dry powder and large lumps. This treatment is to avoid over-mixing, which can form bubbles that are difficult to eliminate. Otherwise, it may cause premature over-hydration and / or cause thickeners such as cellulose ethers to dissolve prematurely and trap air, forming bubbles that are difficult to eliminate.

[0024] The discharge end of the mixing tank 4 is connected to the inlet end of the pulping tank 5, feeding the premixed material into the pulping tank 5. High-intensity shear force is applied to the premixed material for stirring and pulping, resulting in a smooth, uniform, fine, and particle-free liquid homogenized slurry with appropriate viscosity and thixotropy, which is the mortar. The discharge end of the pulping tank 5 is connected to the inlet end of the water washing filter press 6, feeding the mortar into the water washing filter press 6. The pulping tank 5 uses a high-speed, high-shear mixer, such as a high-speed dispersion disc mixer, a high-speed paddle mixer, or a stator-rotor homogenizer, which provides strong shear force and turbulence. The pulping time is relatively long and more critical, typically 2-5 minutes or longer. Insufficient time will lead to uneven dispersion and poor performance; excessive time may introduce too many air bubbles or damage the established structure.

[0025] The water-washing filter press 6 performs filter pressing on the slurry. The solid-liquid separated liquid enters the filtrate tank 10 for temporary storage, while the filter cake remains in the vertical filter press. The filter cake undergoes multi-stage countercurrent washing with water from the primary washing tank 7, secondary washing tank 8, and clear water tank 9. The washed filter cake is then output and conveyed to subsequent processing equipment via a conveyor belt. The moisture content of this filter cake is ≤35%, and the Cl- content is ≤2%, classifying it as qualified dechlorination bypass vent ash. After unloading, the filter cake is conveyed by belt to a ton bag for further processing. The input end of the clear water tank 9 is connected to a clean water source, and the clear water tank 9 is the only source of clean water in this system. Both the input and output ends of the clear water tank are controlled by solenoid valves to open and close the water flow.

[0026] The multi-stage countercurrent washing structure includes: the input end of the water washing filter press 6 is connected to the main input water circuit; the output ends of the secondary water washing tank 8 and the clear water tank 9 are both connected to the main input water circuit through branch input water circuits; the output end of the water washing filter press 6 is connected to the main output water circuit; and the output ends of the primary water washing tank 7 and the secondary water washing tank 8 are both connected to the main output water circuit through branch output water circuits. A horizontal pipe 11 can be installed on the main output water circuit. The sedimentation separation technology using the horizontal pipe 11 can improve the sedimentation effect within the liquid. The vertical cross-sectional shape of a single horizontal pipe 11 is rhomboid, and a sludge discharge port is provided on the side of the bottom of the pipe. When water flows into the rhomboid pipe, the precipitated suspended solids will slide out of the sludge discharge port along the side bottom and enter the sludge channel separated from the water flow. The suspended solids are separated from the water in a timely manner through the horizontal pipe 11, with water flowing through the water channel and sludge flowing through the sludge channel, avoiding pipe blockage and alum runoff, thus improving sedimentation efficiency. The filtrate tank 10, the clean water tank 9, the primary water washing tank 7, and the secondary water washing tank 8 are all connected to the water washing filter press 6 by solenoid valves to control the water flow.

[0027] Specific work steps:

[0028] The liquid in the primary washing tank 7 is pumped to the vertical filter press to wash the filter cake for the first time. The liquid after the first washing enters the measuring tank 3. This liquid has the highest concentration of substances after washing and does not need to be treated. Only the liquid needs to be used to prepare slurry, which can save filtration steps and achieve better overall filtration effect.

[0029] Then the liquid in the secondary washing tank 8 is pumped to the vertical filter press to wash the filter cake a second time, and the washed liquid enters the primary washing tank 7.

[0030] Finally, the water in the clear water tank 9 is pumped to the vertical filter press for a third washing of the filter cake. The filtrate after washing enters the secondary water washing tank 8.

[0031] This technology is not limited to only three-stage washing; it can also add two or more washing tanks. The water washing filter press 6 is connected to the two or more washing tanks. According to the aforementioned operating steps, the water in the two or more washing tanks enters the water washing filter press 6 for washing and then enters the two-stage washing tank 8. The water in the clean water tank 9 enters the water washing filter press 6 for washing and then enters the two or more washing tanks.

[0032] An intermediate tank 12 is provided between the water washing filter press 6 and at least two stages of water washing tanks and clean water tank 9. The output ends of the at least two stages of water washing tanks and clean water tank 9 are all connected to the input end of the intermediate tank 12, and the output end of the intermediate tank 12 is connected to the input end of the water washing filter press 6; or, the output end of the water washing filter press 6 is connected to the input end of the intermediate tank 12, and the output end of the intermediate tank 12 is connected to the input ends of the at least two stages of water washing tanks and clean water tank 9 respectively.

[0033] To prevent equipment or pipeline malfunctions during production, such as Figure 2 As shown, this technology provides an intermediate tank 12 for transition between the water washing filter press 6 and the primary water washing tank 7, secondary water washing tank 8, and clean water tank 9. When the primary water washing tank 7, secondary water washing tank 8, or clean water tank 9 malfunctions, the liquid output from the water washing filter press 6 can be controlled to enter the intermediate tank 12. This allows for maintenance of the malfunctioning equipment without stopping the entire system, simply by disconnecting the faulty equipment, without affecting the overall water washing process. Specifically, the outputs of the primary water washing tank 7, secondary water washing tank 8, and clean water tank 9 are all connected to the input of the intermediate tank 12, and the output of the intermediate tank 12 is connected to the input of the water washing filter press 6; alternatively, the output of the water washing filter press 6 is connected to the input of the intermediate tank 12, and the output of the intermediate tank 12 is connected to the inputs of the primary water washing tank 7, secondary water washing tank 8, and clean water tank 9, respectively.

[0034] Although the present invention has been described in detail above with general descriptions and specific embodiments, some modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A bypass ventilation and ash washing system, characterized in that: The system includes a water-washing filter press for solid-liquid separation of mortar containing bypass windbreak ash. The output end of the water-washing filter press is connected to a filtrate tank. The water-washing filter press, together with a primary water-washing tank, a secondary water-washing tank, and a clean water tank, forms a two-stage circulating water circuit. Water from the primary water-washing tank enters the water-washing filter press for washing and then enters the mortar preparation equipment. Water from the secondary water-washing tank enters the water-washing filter press for washing and then enters the primary water-washing tank. Water from the clean water tank enters the water-washing filter press for washing and then enters the secondary water-washing tank. The filtrate tank, clean water tank, primary water-washing tank, and secondary water-washing tank are all connected to the water-washing filter press by solenoid valves to control the water flow.

2. The bypass ventilation and ash washing system according to claim 1, characterized in that: The water washing filter press can be connected to a secondary or higher water washing tank. Water from the secondary or higher water washing tank enters the water washing filter press for washing and then enters the secondary water washing tank. Water from the clean water tank enters the water washing filter press for washing and then enters the secondary or higher water washing tank.

3. The bypass ventilation and ash washing system according to claim 1, characterized in that: The input end of the water washing filter press is connected to the main input water circuit, and the output ends of the secondary water washing tank and the clear water tank are both connected to the main input water circuit through branch input water circuits; The output end of the water washing filter press is connected to the main output water circuit, and the input ends of the primary water washing tank and the secondary water washing tank are both connected to the main output water circuit through branch output water circuits.

4. A bypass venting and ash washing system according to any one of claims 1-3, characterized in that: The feed end of the water washing filter press is connected to a pulping tank, the input end of the pulping tank is connected to a mixing tank, the input end of the mixing tank is connected to a metering tank and a water measuring tank respectively, and the input end of the metering tank is connected to a feeding device for bypassing wind ash.

5. A bypass ventilation and ash washing system according to claim 4, characterized in that: The input end of the measuring tank is connected to a washing tank or a clean water tank.

6. A bypass ventilation and ash washing system according to claim 1, characterized in that: An intermediate tank is provided between the water washing filter press and the primary water washing tank, the secondary water washing tank, and the clean water tank for transition. The output ends of the primary water washing tank, the secondary water washing tank, and the clean water tank are all connected to the input end of the intermediate tank, and the output end of the intermediate tank is connected to the input end of the water washing filter press. Alternatively, the output end of the water washing filter press is connected to the input end of the intermediate tank, and the output end of the intermediate tank is connected to the input ends of the primary water washing tank, the secondary water washing tank, and the clean water tank, respectively.

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