MEDIA FILTER HAVING NONPOWERED MIXING AND COAGULATION BASIN, AND SEAWATER DESALINATION PLANT AND DISSOLVED AIR FLOATATION APPARATUS USING SAME

• US 20200131060A1
• Filed: 12/26/2019
• Published: 04/30/2020
• Est. Priority Date: 05/04/2015
• Status: Active Grant

• Current Assignee: Doosan Heavy Industries and Construction Company Limited
• Original Assignee: Doosan Heavy Industries and Construction Company Limited
• Inventors: PARK, Yong Hae, PARK, Sung Won, PARK, Byung Sung, WOO, Sung Woo
• Granted Patent: US 11,427,486 B2
• Time in Patent Office: Days
• CPC Class Codes: B01D 2311/04 Specific process operations in the feed stream; Feed pretreatment
• CPC Class Codes: B01D 2311/2649 Filtration
• CPC Class Codes: B01D 61/04 Feed pretreatment
• CPC Class Codes: C02F 1/004 using large scale industrial sized filters
• CPC Class Codes: C02F 1/24 by flotation C02F1/465 takes precedence
• CPC Class Codes: C02F 1/283 using coal, charred products, or inorganic mixtures containing them
• CPC Class Codes: C02F 1/441 by reverse osmosis
• CPC Class Codes: C02F 1/52 by flocculation or precipitation of suspended impurities C02F1/463 takes precedence
• CPC Class Codes: C02F 1/5209 Regulation methods for flocculation or precipitation
• CPC Class Codes: C02F 1/5281 Installations for water purification using chemical agents
• CPC Class Codes: C02F 2103/08 Seawater, e.g. for desalination
• CPC Class Codes: C02F 2301/024 Turbulent
• CPC Class Codes: C02F 9/00 Multistage treatment of water, waste water or sewage
• CPC Class Codes: Y02A 20/131 Reverse-osmosis
• CPC Class Codes: Y02W 10/10 Biological treatment of water, waste water, or sewage

Abstract

A nonpowered mixing and coagulation basin is provided, which generates turbulences of at least two kinds inside the mixing and coagulation basin to which the raw water flows so that foreign matters contained in the raw water come into contact with each other while circulating by a water flow to be coagulated into a predetermined size, and a dissolved air floatation device using the same. The nonpowered mixing and coagulation basin has multiple stages with different packing materials and packing densities to form turbulent flows inside the raw water and control a flow speed, thereby uniformly mixing raw water and coagulant to enhance coagulation efficiency. The nonpowered mixing and coagulation basin simultaneously carries out mixing and coagulation at the front end part of the water treatment system, reduces equipment expenses by having no electric motor and agitator, and reduces power consumption because it does not use any power unit.

Claims

1-20. -20. (canceled)

21. A dissolved air floatation (DAF) apparatus which includes a mixing and coagulation basin for coagulating flocs when coagulant is put in raw water and a floatation basin for floating and removing flocs when microbubbles are injected to the raw water, the DAF apparatus comprising:

a first mixing and coagulation part which is filled with first turbulence derivatives to generate turbulence to form flocs in the raw water; and

a second mixing and coagulation part which is filled with second turbulence derivatives to generate turbulence slower than the turbulence of the first mixing and coagulation part so as to grow the flocs in the raw water passing the first mixing and coagulation part.

22. The DAF apparatus according to claim 21, further comprising:

an additional coagulation basin having an agitator mounted between the mixing and coagulation basin and the floatation basin.

23. The DAF apparatus according to claim 21, further comprising:

a bypass channel disposed below the first mixing and coagulation part to transfer treated water passing the first mixing and coagulation part to a rear end without passing through the second mixing and coagulation part.

24. The DAF apparatus according to claim 21, wherein the first mixing and coagulation part is disposed above the second mixing and coagulation part so that the raw water passing the first mixing and coagulation part is supplied to the second mixing and coagulation part by gravity.

25. The DAF apparatus according to claim 21, wherein the first turbulence derivatives include at least one of mesh-type materials which are stacked and a plurality of fiber aggregates which get tangled together.

26. The DAF apparatus according to claim 21, wherein the second turbulence derivatives include a plurality of pall ring type materials.

27. The DAF apparatus according to claim 26, wherein the second mixing and coagulation part includes a plurality of stages spaced apart from each other and respectively filled with the pall ring type materials.

28. The DAF apparatus according to claim 22, further comprising:

a bypass channel disposed below the first mixing and coagulation part to transfer treated water passing the first mixing and coagulation part to a rear end without passing through the second mixing and coagulation part,

wherein the agitator is operated such that first and second flows of the treated water are selectively controlled according to conditions of the raw water requiring water treatment, the first flow directing the treated water to the floatation basin through the second mixing and coagulation part and the additional coagulation basin from the first mixing and coagulation part, the second flow directing the treated water to the floatation basin through the bypass channel and the additional coagulation basin from the first mixing and coagulation part.

29. The DAF apparatus according to claim 22, further comprising:

a bypass channel disposed below the first mixing and coagulation part to transfer treated water passing the first mixing and coagulation part to a rear end without passing through the second mixing and coagulation part,

wherein the agitator is operated such that third and fourth flows of the treated water are selectively controlled according to conditions of the raw water requiring water treatment, the third flow directing the treated water to the floatation basin through the second mixing and coagulation part from the first mixing and coagulation part, the fourth flow directing the treated water to the floatation basin through the bypass channel from the first mixing and coagulation part.

30. The DAF apparatus according to claim 21, wherein the mixing and coagulation basin is disposed at a front end of the floatation basin.

31. A dissolved air floatation (DAF) apparatus which includes a nonpowered mixing and coagulation basin to form and grow flocs, the basin containing coagulant injected into raw water and particles inside the raw water and having a downstream area communicating with a plurality of filter basins configured to filter and remove flocs contained in the raw water, the DAF apparatus comprising:

a first mixing and coagulation part which is a compartment for holding the raw water and includes a watertight space that occupies a bottom portion of the compartment and is filled with first turbulence derivatives to generate turbulence to form flocs the flocs in the raw water; and

a second mixing and coagulation part which is filled with second turbulence derivatives to generate turbulence slower than the turbulence of the first mixing and coagulation part so as to additionally grow the flocs in the raw water passing from the first mixing and coagulation part,

wherein the mixing and coagulation basin is disposed inside a supply channel through which the raw water is transferred from the nonpowered mixing and coagulation basin to the plurality of filter basins, and

wherein the supply channel comprises a distribution channel which supplies the raw water to the plurality of the filter basins and inside which the second mixing and coagulation part is disposed.

32. The DAF apparatus according to claim 31, further comprising:

a porous separation membrane that partitions the first mixing and coagulation part from the second mixing and coagulation part in order to maintain different turbulence intensities between the first mixing and coagulation part and the second mixing and coagulation part.

33. The DAF apparatus according to claim 31, wherein the first mixing and coagulation part is disposed above the second mixing and coagulation part so that the raw water passing the first mixing and coagulation part is supplied to the second mixing and coagulation part by gravity.

34. The DAF apparatus according to claim 31, wherein the first turbulence derivatives include one of mesh-type materials which are stacked and a plurality of fiber aggregates which get tangled together.

35. The DAF apparatus according to claim 31, wherein the second turbulence derivatives include a plurality of pall ring type materials.

36. The DAF apparatus according to claim 35, wherein the second mixing and coagulation part includes a plurality of stages spaced apart from each other and respectively filled with the pall ring type materials.

37. The DAF apparatus according to claim 36, wherein the plurality of stages are disposed in decreasing order of packing density of the pall ring type materials toward a downstream side.

38. The DAF apparatus according to claim 31,

wherein the supply channel further comprises an inflow channel through which the raw water to be treated flows in from the outside,

wherein the inflow channel comprises a first partition which is mounted at right angles to a bottom of the inflow channel and at a position spaced apart from the bottom of the inflow channel at a predetermined interval to partition an inner space of the inflow channel into a plurality of inner spaces, the inner spaces of the inflow channel partitioned by the first partition being respectively filled with the first turbulence derivatives, and

wherein the raw water passes the first turbulence derivatives in a first direction from an inflow pipe of the first mixing and coagulation part and then passes the first turbulence derivatives in a second direction opposite to the first direction to be transferred to the distribution channel.