Pickling device for preventing scaling in submerged combustion evaporator and feed pipe

Abstract

The utility model discloses a pickling device for preventing scaling inside a submerged combustion evaporator and a feed pipe, which relates to the technical field of environmental engineering and comprises a stock solution pool, an evaporator and a feed pipe connected between the stock solution pool and the evaporator, and the feed pipe is connected with a pickling dosing system for removing scaling inside the evaporator and the feed pipe; the device is reasonable in design, and the scaling probability in the feed pipe and the evaporator can be effectively relieved by adopting a regular pickling process. According to the utility model, the blockage of the feed pipe and the scaling inside the evaporator can be quickly and timely treated. When the feeding flow is reduced and the pressure difference exists between the steam space and the steam pipeline, treatment can be timely and effectively carried out, and scaling substances which are difficult to treat are prevented from being formed to influence normal production; and labor is saved. The pickling device disclosed by the utility model does not need manual pipe disassembly, blockage clearing and the like, and can greatly save labor cost.

Description

Technical Field

[0001] The utility model relates to the technical field of environmental engineering, and more specifically to the technical field of a pickling device for preventing a feed pipe of an immersion combustion evaporator and scaling inside the evaporator. Background Art

[0002] SCE submerged combustion evaporation technology is applied to the full-scale terminal treatment of DTRO concentrate of landfill leachate. The technology mainly includes SCE evaporation system, steam condensation system, centrifugal desludging system and non-condensable gas treatment system. The SCE evaporation system consists of raw liquid pool, feeding system, evaporator, etc. This technology mainly uses natural gas or biogas as a heat source, and the high-temperature flue gas generated is in direct contact with the concentrated liquid in the form of microbubbles for heat exchange, realizing heat exchange evaporation without partitions. During the evaporation and concentration process, the water and volatile substances in the concentrated liquid escape from the evaporator through the steam pipe in the form of steam or non-condensable gas. Finally, after passing through the steam condensation system and the non-condensable gas treatment system, the steam forms condensed water that meets the discharge standards, and the non-condensable gas is discharged from the exhaust pipe after treatment. The non-volatile organic matter and salt in the concentrated liquid form saturated residual liquid, and enter the sediment collection tank under the action of gravity. Finally, through the solid-liquid separation system, the centrifugal separated salt mud goes to the power plant for incineration, and the evaporated mother liquor flows back to the raw liquid pool.

[0003] The water inlet of the SCE evaporation system is controlled in real time by a screw pump and a liquid level gauge in the evaporator. The concentrated liquid enters the evaporator through the feed pipe and evaporates and crystallizes in the evaporator. The evaporator and its feed pipe together constitute the core components of the submerged combustion evaporation system. Once a failure occurs, it will seriously affect the system output and even cause abnormal shutdown. Therefore, the normal operation of the evaporator and its feed pipe is of vital importance.

[0004] Due to its technical characteristics, the DTRO concentrate produced by the membrane treatment process of landfill leachate is rich in a large amount of inorganic salts and difficult-to-degrade organic matter. It has been determined that the concentrations of calcium and magnesium ions in the feed concentrate are 1300 mg / L and 612 mg / L, respectively. After the DTRO concentrate is evaporated and concentrated, the calcium, magnesium ions and anions in the evaporation mother liquor continue to be enriched, and after returning to the original liquid pool, the salt content in the evaporator feed water sample is further increased. The evaporating liquid temperature is 80-90°C. At this temperature, cations such as calcium and magnesium are prone to generate carbonates, sulfates, etc., and then adhere to the feed pipe, the inner wall of the evaporator, the orifice plate, etc. to form harder scale. During the long-term production and operation of the evaporation system, the feed pipe is severely scaled and blocked, and the outlet orifice plate inside the evaporator is severely scaled, resulting in a sudden drop in feed flow, obstruction of steam escape, and poor drainage.

[0005] When the feed pipe and evaporator are seriously scaled, manual cleaning is required to clear the pipes and evaporator. Manual cleaning has the following disadvantages:

[0006] When the feed pipe is blocked, it is necessary to manually dismantle the pipeline and then clear it. This method consumes a lot of man-hours and causes a waste of resources. At the same time, some pipelines are at high positions, which poses a great safety risk.

[0007] The manual cleaning cycle is long, affecting normal production tasks, and manual cleaning and descaling are generally not thorough and cannot restore to good operating conditions;

[0008] Manual knocking, pecking and other methods will cause damage to the structure of the impacted parts such as the feed pipe and the inner wall of the evaporator, reducing the service life of the equipment;

[0009] Some feed pipes are welded to the evaporator and cannot be disassembled manually. It is difficult to remove the scale by high-pressure flushing and other methods, making it a problem that cannot be solved manually. Utility Model Content

[0010] The purpose of the utility model is to solve the technical problem that the existing feed pipe and evaporator are easy to scale and difficult to clean manually. The utility model provides an acid cleaning device for preventing the submerged combustion evaporator and the feed pipe from scaling. It can effectively prevent the feed pipe and the evaporator from scaling under long-term operation of the submerged combustion evaporator, and ensure the safe and stable operation of the evaporator.

[0011] In order to achieve the above-mentioned purpose, the utility model specifically adopts the following technical solutions:

[0012] The utility model provides a pickling device for preventing scale from forming inside an immersion combustion evaporator and a feed pipe, comprising a stock liquid pool, an evaporator, and a feed pipe connected between the stock liquid pool and the evaporator, wherein the feed pipe is connected with a pickling dosing system for removing scale from the evaporator and the feed pipe.

[0013] In one embodiment, a screw feed pump, a first feed valve, an outlet valve and a second feed valve are sequentially arranged on the feed pipe.

[0014] In one embodiment, the pickling dosing system includes an acid pipe, a reagent tank, an acid reflux pipe and an emptying pipe. The lower ends of the acid pipe and the acid reflux pipe are connected to the top of the reagent tank, the upper end of the acid pipe is connected to the feed pipe between the first feed valve and the outlet valve, the upper end of the acid reflux pipe is connected between the outlet valve and the second feed valve, and the emptying pipe is connected to the bottom of the reagent tank.

[0015] In one embodiment, an agitator is disposed inside the medicine tank, and the agitator includes a vertically disposed agitating rod and a stirring blade disposed at the bottom of the agitating rod, and the top of the agitating rod extends out of the top of the medicine tank through a bearing and is connected to a driving motor.

[0016] In one embodiment, it also includes a water inlet pipe and a hydrochloric acid feed pipe both connected to the top of the medicine tank, the water inlet pipe is connected to the tap water pipeline, the hydrochloric acid feed pipe is connected to the hydrochloric acid storage tank, and control valves are provided on the water inlet pipe and the hydrochloric acid feed pipe.

[0017] In one embodiment, an acid injection valve and a cleaning pump are provided on the acid pipe, a waste liquid discharge pipe is connected to the acid pipe between the acid injection valve and the cleaning pump, and a drain valve is provided on the waste liquid discharge pipe.

[0018] In one embodiment, an acid liquid reflux valve is provided on the acid liquid reflux pipe.

[0019] In one embodiment, a drain valve is provided on the drain pipe.

[0020] In one embodiment, the pharmaceutical tank is a PE tank.

[0021] In one embodiment, a sludge collecting tank is provided at the bottom of the evaporator.

[0022] Working principle: It includes an evaporation system (including an evaporator and a sediment collection tank). The evaporation system is connected to a feed pipe externally. The original liquid is pumped into the evaporator through a screw feed pump. A pickling dosing system is provided between the feed pipe and the evaporator. The pickling system includes an acid pipe, a reagent tank, an agitator, an acid reflux pipe, an emptying pipe, a water inlet pipe and a hydrochloric acid feed pipe. The water inlet pipe is connected to the original water supply line of the evaporation system; the agitator is arranged inside the reagent tank; the cleaning pump is connected to the reagent tank through a pipeline, and the other end of the cleaning pump is connected to the feed pipe through an acid pipe (when there are multiple feed pipes, the other end of the cleaning pump is connected to multiple feed pipes through multiple acid pipes), the cleaning pump is connected to a waste liquid discharge pipe externally, and the waste liquid emptying pipe is connected to the supernatant reflux pipe. An acid injection valve is provided between the cleaning pump and the feed pipe. The acid reflux pipe recycles the acid after cleaning the feed pipe.

[0023] The beneficial effects of the utility model are as follows:

[0024] 1. During the long-term operation of the evaporator of the utility model, the feed pipe and the inside of the evaporator are not easy to scale. In the early days, each evaporator needed to dismantle its feed pipe every quarter, manually dredge the pipe, and check and clean the scaling problem inside the evaporator. The regular pickling process can effectively reduce the probability of scaling in the feed pipe and the inside of the evaporator.

[0025] 2. The utility model can quickly and timely handle the blockage of the feed pipe and the scaling inside the evaporator. When the feed flow rate is reduced and there is a pressure difference between the steam space and the steam pipe, it can be handled promptly and effectively to avoid the formation of difficult-to-handle scaling and affect normal production;

[0026] 3. Save labor. The pickling device of the utility model does not need manual pipe dismantling and blockage clearing, etc., which can save a lot of labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the utility model;

[0028] Figure numerals: 1-raw liquid tank, 2-screw feed pump, 3-first feed valve, 4-acid solution injection valve, 5-export valve, 6-second feed valve, 7-acid solution reflux valve, 8-evaporator, 9-sediment collection tank, 10-medicine tank, 11-mixer, 12-cleaning pump, 13-drain valve, 14-drain valve. A-feed pipe, B-acid solution pipe, C-acid solution reflux pipe, D-drain pipe, E-waste liquid discharge pipe. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0032] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0033] like Figure 1As shown, the pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe includes a raw liquid tank 1, an evaporator 8, and a feed pipe connecting the raw liquid tank 1 and the evaporator 8, and the feed pipe is connected to a pickling dosing system for removing scaling inside the evaporator 8 and the feed pipe.

[0034] The feed pipe is provided with a screw feed pump 2, a first feed valve 3, an outlet valve 5 and a second feed valve 6 in sequence.

[0035] The pickling dosing system includes an acid pipe, a reagent tank 10, an acid reflux pipe and an emptying pipe. The lower ends of the acid pipe and the acid reflux pipe are connected to the top of the reagent tank 10, the upper end of the acid pipe is connected to the feed pipe between the first feed valve 3 and the outlet valve 5, the upper end of the acid reflux pipe is connected between the outlet valve 5 and the second feed valve 6, and the emptying pipe is connected to the bottom of the reagent tank 10.

[0036] An agitator 11 is disposed inside the medicine tank 10 . The agitator 11 includes a vertically disposed agitator rod and a stirring blade disposed at the bottom of the agitator rod. The top of the agitator rod extends out of the top of the medicine tank 10 through a bearing and is connected to a driving motor.

[0037] It also includes a water inlet pipe and a hydrochloric acid feed pipe both connected to the top of the reagent tank 10, the water inlet pipe is connected to the tap water pipeline, the hydrochloric acid feed pipe is connected to the hydrochloric acid storage tank, and control valves are provided on the water inlet pipe and the hydrochloric acid feed pipe.

[0038] The acid pipe is provided with an acid injection valve 4 and a cleaning pump 12 , and a waste liquid discharge pipe is connected to the acid pipe between the acid injection valve 4 and the cleaning pump 12 , and a drain valve 14 is provided on the waste liquid discharge pipe.

[0039] An acid liquid reflux valve 7 is provided on the acid liquid reflux pipe.

[0040] A drain valve 13 is provided on the drain pipe.

[0041] The medicine tank 10 is a PE tank.

[0042] A sediment collecting tank 9 is provided at the bottom of the evaporator 8 .

[0043] Working principle: The evaporation system (including evaporator 8 and sediment collection tank 9) is connected to the feed pipe outside the evaporation system, and the raw liquid is pumped into the evaporator 8 through the screw feed pump 2. A pickling dosing system is arranged between the feed pipe and the evaporator 8. The pickling system includes an acid pipe, a reagent tank 10, an agitator 11, an acid reflux pipe, an emptying pipe, a water inlet pipe and a hydrochloric acid feed pipe. The water inlet pipe is connected to the original water supply pipeline of the evaporation system; the agitator 11 is arranged inside the reagent tank 10; the cleaning pump 12 is connected to the reagent tank 10 through a pipeline, and the other end of the cleaning pump 12 is connected to the feed pipe through the acid pipe (when there are multiple feed pipes, the other end of the cleaning pump 12 is connected to multiple feed pipes through multiple acid pipes), the cleaning pump 12 is connected to the waste liquid discharge pipe, and the waste liquid emptying pipe is connected to the supernatant reflux pipe. An acid injection valve 4 is arranged between the cleaning pump 12 and the feed pipe. The acid reflux pipe recovers the acid after cleaning the feed pipe.

[0044] Example 1

[0045] This embodiment provides a judgment on the pickling node of the feed pipeline: when the evaporator 8 is shut down and has not been running for a long time, the feed pipeline of the evaporator 8 should be pickled; during the production process of the evaporator 8, it is found that the feed flow rate decreases (after draining, the feed flow rate is less than 3m 3 / h), the feed pipeline of the evaporator 8 should be pickled;

[0046] When the evaporator 8 is running smoothly, the feed pipeline can be pickled every three months or so. Preparation of pickling agent: add clean water to the agent tank through the clean water pipe, and add the amount to about 3 / 5 of the agent tank; after adding clean water, pump in an appropriate amount of pickling agent (which can be acid cleaning agent, hydrochloric acid, citric acid, etc.) with a dosing pump, and add it to the agent tank 10, and the amount of acid solution added is about 4 / 5 of the agent tank; after adding acid solution, add clean water again through the clean water pipe until the entire agent tank is filled, turn on the agitator 11 to mix the pickling agent evenly and adjust the pH to about 2-3.

[0047] Feed pipeline pickling operation: first close the corresponding screw feed pump 2, open the acid injection valve 4, close the second feed valve 6 of the evaporator 8, and open the acid reflux valve 7; turn on the cleaning pump 12, and circulate and clean the feed pipeline for about 15 minutes; observe the feed pipe flow meter until the flow becomes larger and stabilizes at the maximum value (the maximum flow of the cleaning pump is 500L / h), and observe the cleaning reflux liquid at the same time. When the color of the reflux liquid is stable and no large amount of foam is generated, it can be determined that the cleaning is completed; after the cleaning is completed, the residual mixed liquid in the reagent tank 10 is pumped into the supernatant pool; after the reagent tank 10 is emptied, clean water is injected into the tank again, and the residual acid in the feed pipe is cleaned by circulating clean water. After the cleaning is completed, the clean water is discharged into the ditch through the drain pipe to complete the cleaning of the entire pipeline.

[0048] Example 2

[0049] For the judgment of the pickling and soaking node inside the evaporator 8: when the evaporator 8 is shut down and has not been running for a long time, the evaporator 8 should be pickled and soaked; during the production process of the evaporator, when the pressure difference between the steam space pressure and the steam pipeline pressure exceeds 1.2kPa, the evaporator 8 should be pickled and soaked; when the evaporator is running smoothly, the evaporator can be pickled and soaked every 15-20 days. Preparation of pickling agent: add clean water to the agent tank 10 through the clean water pipe, and the amount added is about 3 / 5 of the agent tank 10; after the clean water is added, the dosing pump pumps in an appropriate amount of pickling agent (which can be acid cleaning agent, hydrochloric acid, citric acid, etc.), and adds it to the agent tank 10, and the amount of acid solution added is about 4 / 5 of the agent tank 10; after the acid solution is added, add clean water again through the clean water pipe until the entire agent tank 10 is filled, turn on the agitator 11 to mix the pickling agent evenly and adjust the pH to about 2-3.

[0050] Pickling and soaking operation inside the evaporator 8: First, shut down the corresponding evaporator 8 and drain the liquid in the evaporator 8 (pump to the sediment collection tank 9). Inject clean water sample into the evaporator 8 until the process value reaches about 650 (the set value is 780), then open the acid injection valve 4, the outlet valve 5 and the second feed valve 6, close the acid reflux valve 7, turn on the power of the cleaning pump 12, and add pickling agent into the evaporator 8. After all the acid in the reagent tank 10 is added to the evaporator 8, turn off the cleaning pump 12 and close all the injection valves; add clean water into the reagent tank 10, then open all the injection valves, turn on the cleaning pump 12, and inject clean water into the evaporator 8 until the liquid level in the evaporator 8 reaches the set value of 780, turn off the cleaning pump 12 and all the injection valves, soak the inside of the evaporator tank with the pickling liquid for 2 days and then discharge it to complete the cleaning of the entire pipeline.

Claims

1. A pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe, characterized in that: It comprises a raw liquid pool (1), an evaporator (8), and a feed pipe connected between the raw liquid pool (1) and the evaporator (8), wherein the feed pipe is connected to a pickling and dosing system for removing scale inside the evaporator (8) and the feed pipe; The feed pipe is provided with a screw feed pump (2), a first feed valve (3), an outlet valve (5) and a second feed valve (6) in sequence; The pickling dosing system comprises an acid pipe, a reagent tank (10), an acid return pipe and an emptying pipe. The lower ends of the acid pipe and the acid return pipe are both connected to the top of the reagent tank (10). The upper end of the acid pipe is connected to the feed pipe between the first feed valve (3) and the outlet valve (5). The upper end of the acid return pipe is connected between the outlet valve (5) and the second feed valve (6). The emptying pipe is connected to the bottom of the reagent tank (10).

2. The pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe according to claim 1, characterized in that: The medicine tank (10) is provided with an agitator (11) inside, and the agitator (11) comprises a vertically arranged agitator rod and a stirring blade arranged at the bottom of the agitator rod, and the top of the agitator rod extends out of the top of the medicine tank (10) through a bearing and is connected to a drive motor.

3. The pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe according to claim 1, characterized in that: It also includes a water inlet pipe and a hydrochloric acid feed pipe both connected to the top of the medicine tank (10), the water inlet pipe is connected to the tap water pipeline, the hydrochloric acid feed pipe is connected to the hydrochloric acid storage tank, and control valves are provided on the water inlet pipe and the hydrochloric acid feed pipe.

4. The pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe according to claim 1, characterized in that: The acid liquid pipe is provided with an acid liquid injection valve (4) and a cleaning pump (12); a waste liquid discharge pipe is connected to the acid liquid pipe between the acid liquid injection valve (4) and the cleaning pump (12); and a drain valve (14) is provided on the waste liquid discharge pipe.

5. The pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe according to claim 1, characterized in that: The acid liquid reflux pipe is provided with an acid liquid reflux valve (7).

6. The pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe according to claim 1, characterized in that: The drain pipe is provided with a drain valve (13).

7. The pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe according to claim 1, characterized in that: The medicine tank (10) is a PE tank.

8. The pickling device for preventing scaling inside the submerged combustion evaporator and the feed pipe according to claim 1, characterized in that: A sediment collecting tank (9) is provided at the bottom of the evaporator (8).

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