Sludge dewatering and curing treatment method and device

Abstract

The invention discloses a sludge dewatering and curing treatment method and device, and belongs to the technical field of sludge treatment. According to the method, the three-phase separation treatment is performed on the river sludge by utilizing a fractional step method, and the sludge after the oil phase and the water phase are separated is cured, so that the sludge dewatering and curing treatment steps are simple and effective, and the sludge treatment efficiency is greatly improved; the uniform discharge plate is arranged at the joint of the coagulation tank and the separation tank, sludge entering the separation tank from the coagulation tank is extruded and discharged, the effect of improving the sludge discharge dispersity can be achieved, the mixing degree of the sludge and chemicals can be increased while discharging is conducted, and the overall sludge treatment uniformity of the device is high.

Description

Technical Field

[0001] This invention relates to the field of sludge treatment technology, specifically to a method and apparatus for sludge dewatering and solidification treatment. Background Technology

[0002] The methods for treating river silt are primarily geared towards urban areas. Research on urban river silt treatment methods can provide important reference value for the treatment and disposal of rural river silt. Generally speaking, urban sludge mainly falls into four categories: construction mud, river silt, sewer sludge, and sewage treatment plant sludge. Apart from construction mud, river silt, sewer sludge, and sewage treatment plant sludge contain large amounts of pathogens, parasites (eggs), heavy metals, and certain persistent organic toxins. Improper disposal can cause secondary pollution to the environment.

[0003] The amount of sludge produced is increasing daily with societal development, and the effective treatment and disposal of these large quantities of sludge is receiving growing attention worldwide. Due to differences in specific circumstances across countries, the sludge treatment measures adopted vary. Generally speaking, sludge treatment and disposal methods mainly include ocean dumping, landfilling, fertilizer production, energy production, and building material production.

[0004] Currently, wastewater treatment processes generate large amounts of sludge with extremely high water content. Sludge treatment typically involves a combination of concentration and dewatering. Even after concentration, the water content remains very high, requiring further dewatering to reduce it. Common dewatering methods include natural drying and mechanical dewatering, both of which suffer from cumbersome processes, low efficiency, and high costs.

[0005] In addition, existing treatment devices suffer from uneven mixing during sludge chemical treatment, resulting in insufficient mixing of sludge and chemical agents, which affects sludge treatment efficiency.

[0006] In summary, existing sludge treatment devices have low sludge treatment efficiency and cumbersome sludge dewatering and solidification steps. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a method and apparatus for sludge dewatering and solidification treatment.

[0008] This invention is achieved through the following technical solution:

[0009] A method for sludge dewatering and solidification includes the following steps:

[0010] Step a: Feed the river sludge into the coagulation tank through the feed pipe, and use a scraper to scrape the floating oil on the surface of the coagulation tank into the oil trough for collection, so as to obtain sludge after preliminary oil removal.

[0011] Step b: The river sludge in the coagulation tank continues to pass through the uniform discharge plate and enters the separation tank. pH adjuster, diluent and electrolyte are added to the sludge through an automatic dosing device, and the sludge is stirred by a stirrer. The stirred sludge achieves three-phase separation of oil-water-sludge. The upper layer of oil enters the second oil sludge collection tank from the oil overflow tank for collection, the middle layer of water enters the water storage tank from the drain pipe for collection, and the bottom layer is the dewatered sludge.

[0012] Step c: Add coagulant and solidifying agent to the dewatered sludge. The ratio of sludge, solidifying agent and coagulant is 4:1:0.01. After stirring, open the discharge valve and discharge the sludge into the sludge tank for solidification. The solidified sludge is used as building material.

[0013] The diluent in step b is decane, and the electrolyte is NaCl solution.

[0014] The curing agent in step c is an organic curing agent, including urea-formaldehyde resin, polyester, ethylene oxide, acrylamide gel, and polybutadiene, and the coagulating agent is one or more of chloride salts, sulfates, nitrates, carbonates, and formates.

[0015] The device includes a coagulation tank and a separation tank. The bottom side of the coagulation tank is connected to the separation tank, and a uniform discharge plate is provided at the connection. The surface of the uniform discharge plate is perforated with several extrusion holes. A feed pipe is connected to the lower side of the coagulation tank. A scraper is provided on the upper surface of the coagulation tank, and the scraper is flush with the upper surface of the coagulation tank. An oil floating tank is provided on the upper side of the coagulation tank, and the lower end of the oil floating tank is connected to a first oil sludge collection tank through a first discharge pipe. An agitator is fixed inside the bottom of the separation tank. An automatic dosing device is fixed on the inner wall of the separation tank and is located directly above the uniform discharge plate. An oil overflow tank is provided on the upper side of the separation tank, and the bottom of the oil overflow tank is connected to a second oil sludge collection tank through a second discharge pipe. A drain pipe is connected to the middle side of the separation tank. The coagulation tank is connected to a water storage tank, and a discharge valve is connected to the bottom side of the separation tank.

[0016] The coagulation tank is equipped with an electric heating tube, which is fixed to the side of the uniform discharge plate.

[0017] The temperature of the electric heating element is 45-55°.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] This invention utilizes a stepwise method to perform three-phase separation treatment on river sludge, and then solidifies the sludge after separating the oil and water phases. The sludge dewatering and solidification treatment steps are simple and effective, greatly improving the sludge treatment efficiency.

[0020] The present invention sets a uniform discharge plate at the connection between the coagulation tank and the separation tank to squeeze the sludge entering the separation tank from the coagulation tank and discharge it. This can not only improve the dispersion of sludge discharge, but also increase the mixing degree of sludge and reagents at the same time. The overall sludge treatment uniformity of the device is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of the device of the present invention.

[0022] In the diagram: 1. Coagulation tank; 2. Feed pipe; 3. Floating oil tank; 4. Scraper; 5. Automatic dosing device; 6. First discharge pipe; 7. First oil sludge collection tank; 8. Separation tank; 9. Agitator; 10. Overflow tank; 11. Drain pipe; 12. Water storage tank; 13. Discharge valve; 14. Uniform discharge plate; 15. Extrusion hole; 16. Second discharge pipe; 17. Second oil sludge collection tank. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the accompanying drawings:

[0024] As shown in the attached figure of the instruction manual Figure 1 As shown, a sludge dewatering and solidification treatment method includes the following steps: Step a: River sludge is fed into coagulation tank 1 from feed pipe 2, and the floating oil on the upper surface of coagulation tank 1 is scraped to floating oil tank 3 for collection by scraper 4 to obtain sludge after preliminary removal of oil.

[0025] Step b: The river sludge in the coagulation tank 1 continues to pass through the uniform discharge plate 14 and enters the interior of the separation tank 8. The pH adjuster, diluent and electrolyte are added to the sludge through the automatic dosing device 5, and the sludge is stirred by the agitator 9. The stirred sludge achieves three-phase separation of oil-water-sludge. The upper layer of oil enters the second oil collection tank 17 from the oil overflow tank 10 for collection, the middle layer of water enters the interior of the water storage tank 12 from the drain pipe 11 for collection, and the bottom layer is the dewatered sludge.

[0026] Step c: Add coagulant and solidifying agent to the dewatered sludge. The ratio of sludge, solidifying agent and coagulant is 4:1:0.01. After stirring, open the discharge valve 13 to discharge the sludge into the sludge tank for solidification. The solidified sludge is used as building material.

[0027] The diluent in step b is decane, and the electrolyte is NaCl solution.

[0028] The curing agent in step c is an organic curing agent, including urea-formaldehyde resin, polyester, ethylene oxide, acrylamide gel, and polybutadiene, and the coagulating agent is one or more of chloride salts, sulfates, nitrates, carbonates, and formates.

[0029] The device includes a coagulation tank 1 and a separation tank 8. The bottom side of the coagulation tank 1 is connected to the separation tank 8, and a uniform discharge plate 14 is provided at the connection point. The surface of the uniform discharge plate 14 is provided with a plurality of extrusion holes 15. A feed pipe 2 is connected to the lower side of the coagulation tank 1. A scraper 4 is provided on the upper surface of the coagulation tank 1, and the scraper 4 is flush with the upper surface of the coagulation tank 1. An oil floating tank 3 is provided on the upper side of the coagulation tank 1, and the lower end of the oil floating tank 3 is connected to a first oil sludge collection tank through a first discharge pipe 6. 7. A stirrer 9 is fixed inside the bottom of the separation tank 8. An automatic dosing device 5 is fixed on the inner wall of the separation tank 8. The automatic dosing device 5 is located directly above the uniform discharge plate 14. An oil overflow trough 10 is provided on the upper side of the separation tank 8. The bottom of the oil overflow trough 10 is connected to the second oil collection tank 17 through the second discharge pipe 16. A drain pipe 11 is connected to the middle side of the separation tank 8. The coagulation tank 1 is connected to the water storage tank 12. A discharge valve 13 is connected to the bottom side of the separation tank 8.

[0030] The coagulation tank 1 is equipped with an electric heating tube, which is fixed to the side of the uniform discharge plate 14.

[0031] The temperature of the electric heating element is 45-55°.

[0032] Example

[0033] As shown in the attached figure of the instruction manual Figure 1 As shown, a sludge dewatering and solidification treatment device includes a coagulation tank 1 and a separation tank 8. The bottom side of the coagulation tank 1 is connected to the separation tank 8, and a uniform discharge plate 14 is provided at the connection. The surface of the uniform discharge plate 14 is provided with a plurality of extrusion holes 15. The lower side of the coagulation tank 1 is connected to a feed pipe 2. The upper surface of the coagulation tank 1 is provided with a scraper 4, which is flush with the upper surface of the coagulation tank 1. The upper side of the coagulation tank 1 is provided with an oil floating tank 3, and the lower end of the oil floating tank 3 is connected to the first discharge pipe 6. An oil sludge collection tank 7 is connected. An agitator 9 is fixed inside the bottom of the separation tank 8. An automatic dosing device 5 is fixed on the inner wall of the separation tank 8. The automatic dosing device 5 is located directly above the uniform discharge plate 14. An oil overflow trough 10 is provided on the upper side of the separation tank 8. The bottom of the oil overflow trough 10 is connected to the second oil sludge collection tank 17 through a second discharge pipe 16. A drain pipe 11 is connected to the middle side of the separation tank 8. The coagulation tank 1 is connected to the water storage tank 12. A discharge valve 13 is connected to the bottom side of the separation tank 8.

[0034] The coagulation tank 1 is equipped with an electric heating tube, which is fixed to the side of the uniform discharge plate 14. The temperature of the electric heating tube is 50°C.

[0035] The steps for treating sludge using the treatment device described in this embodiment are as follows:

[0036] Step a: Feed the river sludge into the coagulation tank 1 through the feed pipe 2, and use the scraper 4 to scrape the floating oil on the upper surface of the coagulation tank 1 into the floating oil tank 3 for collection, so as to obtain sludge after preliminary removal of oil.

[0037] Step b: The river sludge in the coagulation tank 1 continues to be heated by the electric heating tube and then evenly discharged from the discharge plate 14 into the separation tank 8. The pH adjuster, diluent and electrolyte are added to the sludge by the automatic dosing device 5, and the sludge is stirred by the agitator 9. The stirred sludge achieves three-phase separation of oil-water-sludge. The upper layer of oil enters the second oil collection tank 17 from the oil overflow tank 10 for collection, the middle layer of water enters the water storage tank 12 from the drain pipe 11 for collection, and the bottom layer is the dewatered sludge.

[0038] Step c: Add coagulant and solidifying agent to the dewatered sludge. The ratio of sludge, solidifying agent and coagulant is 4:1:0.01. After stirring, open the discharge valve 13 to discharge the sludge into the sludge tank for solidification. The solidified sludge is used as building material.

[0039] The diluent in step b is decane, and the electrolyte is NaCl solution.

[0040] The curing agent in step c is an organic curing agent, including urea-formaldehyde resin, polyester, ethylene oxide, acrylamide gel, and polybutadiene, and the coagulating agent is a chloride salt or sulfate.

[0041] This invention employs a stepwise method to perform three-phase separation treatment on river sludge, and then solidifies the sludge after separating the oil and water phases.

[0042] In step b, chemical regulation is used to desorb and demulsify to reduce the oil content in river sludge, while heating and other enhancement methods are used to improve the dewatering performance of the sludge, thus achieving three-phase separation of oil, water and sludge.

[0043] In step c, the solidification technology involves adding a certain component of a solidifying agent to the river sludge, causing stable and irreversible physicochemical reactions that solidify some of the water and toxic substances, giving it a certain strength for stacking, storage, and subsequent treatment. The solidified product has good mechanical properties and resistance to penetration, leaching, wet and dry conditions, freezing, and thawing. The solidifying agent's role is to fix or seal harmful substances (oil, harmful gases, etc.) in the river sludge within an inert substance, significantly reducing their permeability and leaching rate. After solidification, the sludge's mineralization decreased by 46%, the oil content dropped from 40,000 mg / L before solidification to 0.4 mg / L, and the sulfide content was only 0.4 mg / L. Using the solidified product as a building material or for landfilling can meet environmental protection requirements.

[0044] In summary, these are merely preferred embodiments of the present invention and are not intended to limit the scope of the invention. All equivalent variations and modifications made in accordance with the shape, structure, features and spirit described in the claims of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A sludge dehydration and solidification treatment method, characterized in that: The steps include: Step a, feeding the river sludge from the feed pipe (2) into the coagulation tank (1), using a scraper (4) to scrape the floating oil on the upper surface of the coagulation tank (1) into the floating oil tank (3) for collection, and obtaining the sludge after the oil pollution is initially removed; Step b, the river sludge in the coagulation tank (1) continues to pass through the uniform discharge plate (14) and then enters the interior of the separation tank (8), a pH regulator, a diluent, and an electrolyte are added to the sludge through an automatic doser (5), and the sludge is stirred by a stirrer (9), and the stirred sludge is separated into three phases of oil-water-mud, the oil in the upper layer enters the second oil collection tank (17) from the oil overflow tank (10) for collection, the water in the middle layer enters the interior of the water storage tank (12) from the drainage pipe (11) for collection, and the bottom layer is the dehydrated sludge; Step c, adding a coagulant and a curing agent to the dehydrated sludge, wherein the ratio of sludge, curing agent and coagulant is 4:1:0.01, and after stirring, opening the discharge valve (13), and discharging the sludge into a sludge pool for curing. The cured sludge is used as a building material.

2. A sludge dehydration and solidification treatment method according to claim 1, characterized in that: The diluent in step b is decanane, and the electrolyte is NaCl solution.

3. A sludge dehydration and solidification treatment method according to claim 1, characterized in that: The curing agent in step c is an organic curing agent, including urea-formaldehyde resin, polyester, ethylene oxide, acrylamide gel, polybutadiene, and the coagulant is one or more of chloride, sulfate, nitrate, carbonate, and formates.

4. The device used in the sludge dehydration and solidification treatment method according to claim 1 is characterized in that: The device comprises a coagulation tank (1) and a separation tank (8), wherein the bottom side of the coagulation tank (1) is connected to the separation tank (8), and a uniform discharge plate (14) is provided at the connection point, and a plurality of extrusion holes (15) are provided through the surface of the uniform discharge plate (14), and a feed pipe (2) is connected to the lower side of the coagulation tank (1), and a scraper (4) is provided on the upper surface of the coagulation tank (1), and the scraper (4) is flush with the upper surface of the coagulation tank (1), and an oil floating groove (3) is provided on the upper side of the coagulation tank (1), and the lower end of the oil floating groove (3) is connected to a first oil collection tank (1) through a first discharge pipe (6). 7), a stirrer (9) is fixed inside the bottom of the separation tank (8), an automatic doser (5) is fixed on the inner wall of the separation tank (8), and the automatic doser (5) is located directly above the uniform discharge plate (14); an oil overflow trough (10) is provided on the upper side of the separation tank (8), and the bottom of the oil overflow trough (10) is connected to the second oil collection tank (17) through a second discharge pipe (16); a drain pipe (11) is connected to the middle side of the separation tank (8), the coagulation tank (1) is connected to the water storage tank (12), and a discharge valve (13) is connected to the bottom side of the separation tank (8).

5. The device used in the sludge dehydration and solidification treatment method according to claim 1 is characterized in that: An electric heating pipe is provided inside the coagulation tank (1), and the electric heating pipe is fixed to the side of the uniform discharge plate (14).

6. The device used in the sludge dehydration and solidification treatment method according to claim 1, characterized in that: The temperature of the electric heating tube is 45-55°.

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