An integrated calcium and magnesium separation resource water treatment system and method

Abstract

The invention discloses an integrated calcium-magnesium separation and resource utilization water treatment system and method. The outlet of a sodium carbonate dosing system is connected to a sodium carbonate dosing port of a reactor, the sodium hydroxide dosing port of the reactor is connected to the outlet of the sodium hydroxide dosing system, the seed crystal discharge port of the reactor is connected to a seed crystal recovery system, the mud discharge port at the bottom of the reactor is connected to a magnesium hydroxide resource utilization system, the water outlet of a sludge dewatering system is connected to a water inlet of the reactor, the water outlet of the reactor is connected to a water outlet downstream system, the outlet of a coagulant dosing system is connected to a coagulant dosing port of the reactor, the outlet of a seed crystal dosing system is connected to a seed crystal dosing port of the reactor, and the outlet of a coagulant dosing system is connected to a coagulant dosing port of the reactor. The system and method can realize the step-by-step removal of calcium and magnesium ions and the resource utilization of calcium carbonate and magnesium hydroxide.

Description

Technical Field

[0001] The present invention belongs to the technical field of water treatment, and relates to a water softening treatment system and method, and specifically to an integrated calcium and magnesium separation resource water treatment system and method. Background Art

[0002] Membrane and thermal water treatment processes are often used for industrial wastewater treatment. In order to avoid scaling in membrane and thermal water treatment process systems, a softening pretreatment process is generally set up to remove calcium and magnesium hardness ions. Sodium hydroxide, sodium carbonate and calcium and magnesium ions are added to the reactor using a high-density tank or a machine-added tank to generate calcium carbonate and magnesium hydroxide. The solid and liquid are separated under the action of coagulants and flocculants. However, calcium carbonate and magnesium hydroxide cannot be separated separately, resulting in a large amount of waste of calcium and magnesium resources. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide an integrated calcium-magnesium separation and resource recovery water treatment system and method, which can achieve the step-by-step removal of calcium and magnesium ions and the resource recovery of calcium carbonate and magnesium hydroxide.

[0004] To achieve the above-mentioned purpose, the integrated calcium-magnesium separation and resource utilization water treatment system of the present invention includes a sodium carbonate dosing system, a reactor, a sodium hydroxide dosing system, a water supply power system, a seed recovery system, a sludge dewatering system, a magnesium hydroxide resource utilization system, a water outlet downstream system, a coagulant dosing system, a seed dosing system and a coagulant dosing system;

[0005] The outlet of the sodium carbonate dosing system is connected to the sodium carbonate dosing port of the reactor, the sodium hydroxide dosing port of the reactor is connected to the outlet of the sodium hydroxide dosing system, the outlet of the water supply power system is connected to the water inlet of the reactor, the seed discharge port of the reactor is connected to the seed recovery system, the sludge discharge port at the bottom of the reactor is connected to the inlet of the sludge dewatering system, the sludge outlet of the sludge dewatering system is connected to the magnesium hydroxide resource utilization system, the water outlet of the sludge dewatering system is connected to the water inlet of the reactor, the water outlet of the reactor is connected to the water outlet downstream system, the outlet of the coagulant dosing system is connected to the coagulant dosing port of the reactor, the outlet of the seed dosing system is connected to the seed dosing port of the reactor, and the outlet of the coagulant dosing system is connected to the coagulant dosing port of the reactor.

[0006] The crystal seed recovery system includes a crystal seed drainage system, a crystal seed drying system and a calcium carbonate resource utilization system;

[0007] The seed discharge port of the reactor is connected to the inlet of the seed drainage system, the seed outlet of the seed drainage system is connected to the inlet of the seed drying system, the outlet of the seed drying system is connected to the calcium carbonate resource utilization system, and the water outlet of the seed drainage system is connected to the water inlet of the reactor.

[0008] The water outlet of the reactor is connected to the downstream system of the water outlet through a drainage pipe and a turbidity monitoring system.

[0009] The interior of the reactor is divided into a sludge concentration zone and a clear water zone, a clarification zone, a flocculation reaction zone, a fluidized crystallization reaction zone and a buffer zone located above the sludge concentration zone, wherein the fluidized crystallization reaction zone is a double-cylinder structure, the buffer zone is connected to the top inlet of the fluidized crystallization reaction zone, the top outlet of the fluidized crystallization reaction zone is connected to the top inlet of the flocculation reaction zone, the bottom outlet of the flocculation reaction zone is connected to the inlet of the clarification zone, the bottom of the clarification zone is connected to the sludge concentration zone, the top of the clarification zone is connected to the clear water zone, and the downstream water outlet system is connected to the water outlet of the clear water zone;

[0010] The seed crystal discharge port, the water inlet, the sodium hydroxide dosing port and the sodium carbonate dosing port are connected to the bottom side of the fluidized crystallization reaction zone.

[0011] A reactor water distribution device is arranged at the bottom of the fluidized crystallization reaction zone.

[0012] The sodium hydroxide dosing port, the sodium carbonate dosing port, the seed crystal discharge port, the reactor water distribution device and the water inlet are distributed in sequence from top to bottom.

[0013] The side of the clarification area is provided with a high mud level sampling port, a middle mud level sampling port and a low mud level sampling port from top to bottom.

[0014] A scraper is provided on the inner wall of the sludge concentration zone, wherein a driving shaft of the scraper is connected to an output shaft of a scraper motor.

[0015] The pH monitoring system is inserted into the top of the flocculation reaction zone, and the seed crystal observation sampling port is connected to the side of the top of the fluidized crystallization reaction zone.

[0016] The integrated calcium and magnesium separation and resource utilization water treatment method of the present invention comprises the following steps:

[0017] Raw water is added to the reactor through the water inlet. In the reactor, the raw water first enters the fluidized crystallization reaction zone and reacts with the added sodium hydroxide and sodium carbonate to form calcium carbonate on the surface of the seed crystals. The mature seed crystals are discharged from the seed crystal discharge port. The seed crystals are added to the reactor through the seed crystal addition port by the seed crystal addition system.

[0018] The rising water flow in the fluidized crystallization reaction zone enters the buffer zone, and the magnesium hydroxide contacts and mixes with the coagulant and the coagulant aid and then enters the flocculation reaction zone. After the flocs grow up, they enter the clarification zone for solid-liquid separation. Among them, the water flows into the clear water zone and is then discharged through the outlet. The formed magnesium hydroxide floc sludge enters the sludge concentration zone and is then discharged through the sludge discharge port into the sludge dewatering system. The dehydrated solid enters the magnesium hydroxide resource utilization system.

[0019] The present invention has the following beneficial effects:

[0020] During specific operation of the integrated calcium-magnesium separation and resource utilization water treatment system and method described in the present invention, in the reactor, raw water first enters the fluidized crystallization reaction zone, and generates calcium carbonate on the surface of the seed crystals with the added sodium hydroxide and sodium carbonate. The mature seed crystals are discharged from the seed crystal discharge port. The magnesium hydroxide is contacted and mixed with the coagulant and the coagulant aid and then enters the flocculation reaction zone. After the flocs grow, they enter the clarification zone for solid-liquid separation. The formed magnesium hydroxide floc sludge is dehydrated and then enters the magnesium hydroxide resource utilization system, thereby converting calcium resources into calcium carbonate particles for use as a desulfurizer, and converting magnesium resources into magnesium hydroxide for use as a flame retardant filler and deodorant after dehydration, so as to realize the step-by-step removal of calcium and magnesium ions and simultaneously realize the resource utilization of calcium carbonate and magnesium hydroxide. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention.

[0022] Among them, 1 is the water supply power system, 2 is the water supply flow meter, 3 is the water inlet, 4 is the reactor water distribution device, 5 is the sodium hydroxide dosing system, 6 is the sodium carbonate dosing system, 7 is the fluidized crystallization reaction zone, 8 is the seed discharge port, 9 is the seed observation sampling port, 10 is the seed addition port, 11 is the seed addition system, 12 is the pH monitoring system, 13 is the buffer zone, 14 is the coagulant dosing port, 15 is the coagulant dosing system, 16 is the coagulant aid dosing port, 17 is the coagulant aid dosing system, 18 is the flocculation reaction zone, 19 is the clarification zone, 20 is the clean water area, 21 is the drainage pipe, 22 is the turbidity monitoring system, 23 is the downstream effluent system, 24 is the sludge concentration area, 25 is the scraper, 26 is the scraper motor, 27 is the sludge discharge port, 28 is the low mud level sampling port, 29 is the middle mud level sampling port, 30 is the high mud level sampling port, 31 is the sludge dewatering system, 32 is the magnesium hydroxide resource utilization system, 33 is the seed crystal drainage system, 34 is the seed crystal drying system, 35 is the calcium carbonate resource utilization system, 36 is the sodium carbonate dosing port, and 37 is the sodium hydroxide dosing port. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only embodiments of a part of the present invention, not all embodiments, and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts disclosed in the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0024] The accompanying drawings illustrate schematic diagrams of the structures of the disclosed embodiments of the present invention. These figures are not drawn to scale; for the purpose of clarity, some details are exaggerated and some details may be omitted. The shapes of the various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art may design regions / layers with different shapes, sizes, and relative positions as needed.

[0025] refer to Figure 1 The integrated calcium magnesium fractionation resource water treatment system of the present invention comprises a water supply power system 1, a water supply flow meter 2, a water inlet 3, a reactor water distribution device 4, a sodium hydroxide dosing system 5, a sodium carbonate dosing system 6, a fluidized crystallization reaction zone 7, a seed discharge port 8, a seed observation sampling port 9, a seed addition port 10, a seed addition system 11, a pH monitoring system 12, a buffer zone 13, a coagulant dosing port 14, a coagulant dosing system 15, a coagulant aid dosing port 16, a coagulant aid dosing system 17, and a flocculation reaction zone. Area 18, clarification area 19, clear water area 20, drain pipe 21, turbidity monitoring system 22, effluent downstream system 23, sludge concentration area 24, scraper 25, scraper motor 26, sludge discharge port 27, low mud level sampling port 28, middle mud level sampling port 29, high mud level sampling port 30, sludge dewatering system 31, magnesium hydroxide resource utilization system 32, seed crystal drainage system 33, seed crystal drying system 34, calcium carbonate resource utilization system 35, sodium hydroxide dosing port 37 and sodium carbonate dosing port 36;

[0026] The outlet of the sodium carbonate dosing system 6 is connected to the sodium carbonate dosing port 36 of the reactor, the sodium hydroxide dosing port 37 of the reactor is connected to the outlet of the sodium hydroxide dosing system 5, the outlet of the water supply power system 1 is connected to the water inlet 3 of the reactor, the seed discharge port 8 of the reactor is connected to the inlet of the seed drainage system 33, the seed outlet of the seed drainage system 33 is connected to the inlet of the seed drying system 34, the outlet of the seed drying system 34 is connected to the calcium carbonate resource utilization system 35, the water outlet of the seed drainage system 33 is connected to the water inlet 3 of the reactor, and the drainage at the bottom of the reactor is connected to the water inlet 3 of the reactor. The mud inlet 27 is connected to the inlet of the sludge dewatering system 31, the sludge outlet of the sludge dewatering system 31 is connected to the magnesium hydroxide resource utilization system 32, the water outlet of the sludge dewatering system 31 is connected to the water inlet 3 of the reactor, the water outlet of the reactor is connected to the water outlet downstream system 23 through the drain pipe 21 and the turbidity monitoring system 22, the outlet of the coagulant dosing system 17 is connected to the coagulant dosing port 16 of the reactor, the outlet of the seed dosing system 11 is connected to the seed dosing port 10 of the reactor, and the outlet of the coagulant dosing system 15 is connected to the coagulant dosing port 14 of the reactor;

[0027] The interior of the reactor is divided into a sludge concentration zone 24 and a clear water zone 20, a clarification zone 19, a flocculation reaction zone 18, a fluidized crystallization reaction zone 7 and a buffer zone 13 located above the sludge concentration zone 24, wherein the fluidized crystallization reaction zone 7 is a double-cylinder structure, the buffer zone 13 is connected to the top inlet of the fluidized crystallization reaction zone 7, the top outlet of the fluidized crystallization reaction zone 7 is connected to the top inlet of the flocculation reaction zone 18, the bottom outlet of the flocculation reaction zone 18 is connected to the inlet of the clarification zone 19, the bottom of the clarification zone 19 is connected to the sludge concentration zone 24, the top of the clarification zone 19 is connected to the clear water zone 20, and the drain pipe 21 is connected to the clear water zone 20;

[0028] Reactor water distribution device 4 is disposed at the bottom of fluidized crystallization reaction zone 7. Seed crystal discharge port 8, water inlet 3, sodium hydroxide dosing port 37, and sodium carbonate dosing port 36 are connected to the bottom side of fluidized crystallization reaction zone 7. Sodium hydroxide dosing port 37, sodium carbonate dosing port 36, seed crystal discharge port 8, reactor water distribution device 4, and water inlet 3 are sequentially arranged from top to bottom. A high mud level sampling port 30, a mid-level mud level sampling port 29, and a low mud level sampling port 28 are sequentially arranged on the side of clarification zone 19 from top to bottom.

[0029] A scraper 25 is provided on the inner wall of the sludge concentration zone 24, wherein the drive shaft of the scraper 25 is connected to the output shaft of the scraper motor 26; the pH monitoring system 12 is inserted into the top of the flocculation reaction zone 18, and the seed crystal observation sampling port 9 is connected to the side of the top of the fluidized crystallization reaction zone 7.

[0030] The integrated calcium and magnesium separation and resource utilization water treatment method of the present invention comprises the following steps:

[0031] Raw water is added to the reactor through the water inlet 3 by the water supply power system 1. The water supply flow rate at the water inlet 3 is detected by the water supply flowmeter 2. In the reactor, the raw water evenly enters the fluidized crystallization reaction zone 7 through the reactor water distribution device 4, and forms calcium carbonate on the surface of the seed crystals with the added sodium hydroxide and sodium carbonate. The flow rate in the fluidized crystallization reaction zone 7 is high, and the mature seed crystals are discharged from the seed crystal discharge port 8, and then filtered by the seed crystal drainage system 33. Among them, the solid enters the seed crystal drying system 34 for drying and then enters the calcium carbonate resource utilization system 35. In order to ensure the decalcification efficiency, the seed crystal addition system 11 adds seeds to the reactor through the seed crystal addition port 10; the pH monitoring system 12 monitors the pH value of the fluidized crystallization reaction zone 7 and adjusts the dosage of sodium hydroxide according to the monitored pH value. The dosage of the sodium carbonate dosing system 6 is linked to the flow measured by the water supply flowmeter 2 to ensure the hardness removal rate; the filtered water and raw water of the seed crystal drainage system 33 are refluxed and added to the reactor through the water inlet 3;

[0032] The high-speed water flow rising in the fluidized crystallization reaction zone 7 enters the buffer zone 13, and the magnesium hydroxide contacts and mixes with the coagulant and the coagulant aid and enters the flocculation reaction zone 18. After the flocs grow, they enter the clarification zone 19 for solid-liquid separation. Among them, the water flows into the clear water zone 20 and is then discharged through the drain pipe 21. The turbidity monitoring system 22 is installed on the drain pipe 21. The dosage of the coagulant dosing system 15 and the coagulant dosing system 17 is linked to the flow measured by the water flow meter 2 to ensure the turbidity of the outlet water.

[0033] The magnesium hydroxide floc sludge enters the sludge concentration area 24, and the scraper 25 rotates under the drive of the scraper motor 26. The magnesium hydroxide sludge is gathered and then discharged into the sludge dewatering system 31 through the sludge discharge port 27. The dehydrated solid enters the magnesium hydroxide resource utilization system 32. The filtrate output by the sludge dewatering system 31 and the raw water are refluxed and added to the reactor through the water inlet 3. During operation, the height of the mud layer is monitored through the low mud level sampling port 28, the middle mud level sampling port 29 and the high mud level sampling port 30.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. An integrated calcium and magnesium separation resource water treatment system, characterized in that: It includes a sodium carbonate dosing system (6), a reactor, a sodium hydroxide dosing system (5), a water supply power system (1), a seed recovery system, a sludge dewatering system (31), a magnesium hydroxide resource utilization system (32), a water outlet downstream system (23), a coagulant dosing system (17), a seed dosing system (11) and a coagulant dosing system (15); The outlet of the sodium carbonate dosing system (6) is connected to the sodium carbonate dosing port (36) of the reactor, the sodium hydroxide dosing port (37) of the reactor is connected to the outlet of the sodium hydroxide dosing system (5), the outlet of the water supply power system (1) is connected to the water inlet (3) of the reactor, the crystal seed discharge port (8) of the reactor is connected to the crystal seed recovery system, and the mud discharge port (27) at the bottom of the reactor is connected to the magnesium hydroxide resource utilization system (31) through the sludge dehydration system (31). 2) are connected, the water outlet of the sludge dewatering system (31) is connected to the water inlet (3) of the reactor, the water outlet of the reactor is connected to the water outlet downstream system (23), the outlet of the coagulant dosing system (17) is connected to the coagulant dosing port (16) of the reactor, the outlet of the seed dosing system (11) is connected to the seed dosing port (10) of the reactor, and the outlet of the coagulant dosing system (15) is connected to the coagulant dosing port (14) of the reactor; The seed recovery system includes a seed drainage system (33), a seed drying system (34) and a calcium carbonate resource utilization system (35); The seed discharge port (8) of the reactor is connected to the inlet of the seed drainage system (33), the seed outlet of the seed drainage system (33) is connected to the inlet of the seed drying system (34), the outlet of the seed drying system (34) is connected to the calcium carbonate resource utilization system (35), and the water outlet of the seed drainage system (33) is connected to the water inlet (3) of the reactor; The interior of the reactor is divided into a sludge concentration zone (24) and a clear water zone (20) located on the upper side of the sludge concentration zone (24), a clarification zone (19), a flocculation reaction zone (18), a fluidized crystallization reaction zone (7) and a buffer zone (13), wherein the fluidized crystallization reaction zone (7) is a double-cylinder structure, the buffer zone (13) is connected to the top inlet of the fluidized crystallization reaction zone (7), the top outlet of the fluidized crystallization reaction zone (7) is connected to the top inlet of the flocculation reaction zone (18), the bottom outlet of the flocculation reaction zone (18) is connected to the inlet of the clarification zone (19), the bottom of the clarification zone (19) is connected to the sludge concentration zone (24), the top of the clarification zone (19) is connected to the clear water zone (20), and the effluent downstream system (23) is connected to the water outlet of the clear water zone (20); The seed crystal discharge port (8), the water inlet (3), the sodium hydroxide dosing port (37) and the sodium carbonate dosing port (36) are connected to the bottom side of the fluidized crystallization reaction zone (7).

2. The integrated calcium and magnesium separation and resource utilization water treatment system according to claim 1 is characterized in that: The water outlet of the reactor is connected to the water outlet downstream system (23) through a drainage pipe (21) and a turbidity monitoring system (22).

3. The integrated calcium and magnesium separation and resource utilization water treatment system according to claim 1 is characterized in that: A reactor water distribution device (4) is provided at the bottom of the fluidized crystallization reaction zone (7).

4. The integrated calcium and magnesium separation and resource utilization water treatment system according to claim 3 is characterized in that: The sodium hydroxide dosing port (37), the sodium carbonate dosing port (36), the seed crystal discharge port (8), the reactor water distribution device (4) and the water inlet (3) are distributed in sequence from top to bottom.

5. The integrated calcium and magnesium separation and resource utilization water treatment system according to claim 1 is characterized in that: A high mud level sampling port (30), a middle mud level sampling port (29) and a low mud level sampling port (28) are sequentially provided on the side of the clarification zone (19) from top to bottom.

6. The integrated calcium and magnesium separation and resource utilization water treatment system according to claim 1 is characterized in that: A scraper (25) is provided on the inner wall of the sludge concentration zone (24), wherein a drive shaft of the scraper (25) is connected to an output shaft of a scraper motor (26).

7. The integrated calcium and magnesium separation and resource utilization water treatment system according to claim 1 is characterized in that: It also includes a pH monitoring system (12) and a seed crystal observation sampling port (9). The pH monitoring system (12) is inserted into the top of the flocculation reaction zone (18), and the seed crystal observation sampling port (9) is connected to the side of the top of the fluidized crystallization reaction zone (7).

8. An integrated calcium and magnesium separation resource water treatment method, characterized in that: The integrated calcium and magnesium separation and resource utilization water treatment system according to claim 1 comprises the following steps: Raw water is added to the reactor through the water inlet (3). In the reactor, the raw water first enters the fluidized crystallization reaction zone (7), and forms calcium carbonate on the surface of the seed crystals with the added sodium hydroxide and sodium carbonate. The mature seed crystals are discharged from the seed crystal discharge port (8). The seed crystals are added to the reactor through the seed crystal addition port (10) by the seed crystal addition system (11); The rising water flow in the fluidized crystallization reaction zone (7) enters the buffer zone (13), and the magnesium hydroxide contacts and mixes with the coagulant and the coagulant aid and then enters the flocculation reaction zone (18). After the flocs grow, they enter the clarification zone (19) for solid-liquid separation. Among them, the water flow enters the clear water zone (20) and is then discharged through the water outlet. The formed magnesium hydroxide floc sludge enters the sludge concentration zone (24) and is then discharged through the sludge discharge port (27) into the sludge dewatering system (31). The dehydrated solid enters the magnesium hydroxide resource utilization system (32).

Images