Small seawater freezing desalination crystallizer

Abstract

The small seawater freezing desalination crystallizer comprises an upper end bearing, an upper end cover, a rotating shaft, a lower end cover, a lower end bearing, a fixed pipe plate, a shell, an outer layer crystallization pipe, an inner layer crystallization pipe, an annular plate, an inner scraper, an outer scraper, a knife rest, a refrigerant inlet pipe, a refrigerant outlet pipe, a conveying pipe, a water inlet pipe, a first outlet ice water pipe, a second outlet ice water pipe and a variable frequency motor. According to the device, freezing crystallization desalination of seawater is completed mainly through continuous indirect heat exchange between seawater in the inner-layer crystallization pipe and seawater outside the outer-layer crystallization pipe and refrigerants between the inner layer and the outer layer of the crystallization pipe, simultaneous continuous freezing of the inner layer and the outer layer of the crystallization pipe is achieved, the heat exchange area is increased, and the heat exchange efficiency is improved; and the method has a great industrial application prospect.

Description

Technical Field

[0001] The utility model patent relates to the field of seawater desalination, and in particular to a small seawater freezing and desalination crystallizer. Background Art

[0002] With the rapid development of economy, the amount of water used in industry and agriculture has gradually increased, water pollution is serious, and the shortage of fresh water resources has restricted the development of my country's economy. Most of the earth's water resources exist in the form of seawater, making seawater desalination an important way to prepare fresh water. There are mainly distillation, membrane, reverse osmosis, freezing and other methods for seawater desalination. Among them, the crystallizer is an important device in the process of seawater freezing desalination. At present, there are two main types of crystallizers: direct and indirect. The indirect crystallizer mainly includes a scraper and a crystallization tube. If the scraper rotates, the crystallization tube is fixed. Otherwise, the crystallization tube rotates and the scraper is fixed. In the existing crystallizer, seawater is generally crystallized on the inside or outer layer of the crystallization tube, with a small heat exchange area and low heat exchange efficiency.

[0003] In recent years, the country has vigorously developed LNG clean energy. LNG gasification can release a large amount of cold energy. Using this cold energy for seawater desalination can not only achieve the goal of energy conservation and emission reduction, but also solve the problem of fresh water resource shortage.

[0004] In the prior art, the crystallizer disclosed in Chinese patent CN105600859A relies on a motor to drive multiple scrapers through a pulley, which has low transmission efficiency, increases the heat exchange area by increasing the number of crystallization tubes, and has a complex structure; the refrigerant between the shell and the crystallization tube is in contact with the atmosphere, which loses some energy and has a relatively low cold energy utilization rate. Summary of the invention

[0005] The problem to be solved by the utility model is to overcome the shortcomings and deficiencies of the prior art. The device completes the freezing, crystallization and desalination of seawater by continuous indirect heat exchange between the seawater inside the inner crystallization tube and the seawater outside the outer crystallization tube and the refrigerant between the inner and outer layers of the crystallization tube, and realizes that the refrigerant causes the inner and outer layers of the crystallization tube to freeze simultaneously and continuously, thereby increasing the heat exchange area and improving the heat exchange efficiency. The device has a small size, a compact structure and great industrial application prospects.

[0006] The utility model is completed by the following technical scheme. A small-sized seawater freezing and desalination crystallizer comprises an upper end bearing (1), an upper end cover (2), a rotating shaft (3), a lower end cover (4), a lower end bearing (5), a fixed tube sheet (6), a shell (7), an outer layer crystallization tube (8), an inner layer crystallization tube (9), an annular plate (10), an inner scraper (11), an outer scraper (12), a knife holder (13), a refrigerant inlet pipe (14), a refrigerant outlet pipe (15), a delivery pipe (16), a water inlet pipe (17), a first outlet ice water pipe (18), a second outlet ice water pipe (19), and a variable frequency motor (20). The inner layer crystal tube (9) passes through and is fixed on the fixed tube sheet (6), and the upper end cover (2) is fixed at the top by screws, and a first outlet ice water pipe (18) is provided at the upper end of the side surface; the outer layer crystal tube (8) is sleeved outside the inner layer crystal tube (9) and fixed on the fixed tube sheet (6); the lower end of the outer layer crystal tube (8) and the lower end of the inner layer crystal tube (9) are welded and sealed by an annular plate (10); the fixed tube sheet (6) is provided with a refrigerant inlet pipe (14) and a refrigerant outlet pipe (15) located between the outer layer crystal tube (8) and the inner layer crystal tube (9); the delivery pipe (16) is connected to the refrigerant inlet pipe (14), and the number of the delivery pipes (16) is 12 and is evenly distributed between the outer layer crystal tube (8) and the inner layer crystal tube (9); the fixed tube sheet (6) and the lower end cover (4) are fixed to the shell (7) by screws; the lower end of the shell (7) is provided with a water inlet pipe (17), and the upper end of the side surface is provided with a second outlet ice water pipe (19).

[0007] The rotating shaft (3) is located in the inner crystal tube (9) and is fixed by an upper bearing (1) of an upper end cover (2) and a lower bearing (5) of a lower end cover (4); the inner scraper (11) is fixed on the rotating shaft (3) to peel off four ice crystals on the inner side of the inner crystal tube (9); the blade holder (13) is fixed on the rotating shaft (3) located at the lower end of the inner scraper (11); the outer scraper (12) is fixed on the blade holder (13) to peel off four ice crystals on the outer side of the outer crystal tube (8); the variable frequency motor (20) rotates the inner scraper (11) and the outer scraper (12) on the blade holder (13) via the rotating shaft (3).

[0008] The beneficial effects of the utility model are: 1. The device mainly completes the freezing, crystallization and desalination of seawater by continuous indirect heat exchange between the seawater inside the inner crystallization tube and the seawater outside the outer crystallization tube and the refrigerant between the inner and outer layers of the crystallization tube; 2. The device realizes continuous freezing of the refrigerant and the inner and outer layers, increases the heat exchange area, improves the heat exchange efficiency, and has great industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG1 is a schematic diagram of the structure of the utility model.

[0010] FIG2 is a cross-sectional view taken along line AA of FIG1.

[0011] The numbers in the accompanying drawings are respectively: 1-upper end bearing 2-upper end cover 3-rotating shaft 4-lower end cover 5-lower end bearing 6-fixed tube plate 7-shell 8-outer layer crystallization tube 9-inner layer crystallization tube 10-annular plate 11-inner scraper 12-outer scraper 13-knife holder 14-refrigerant inlet pipe 15-refrigerant outlet pipe 16-delivery pipe 17-water inlet pipe 18-first outlet ice water pipe 19-second outlet ice water pipe 20-frequency conversion motor. DETAILED DESCRIPTION

[0012] The following is a detailed introduction to the utility model in conjunction with the accompanying drawings: Figures 1 to 2 As shown, a small-sized seawater freezing and desalination crystallizer comprises an upper end bearing (1), an upper end cover (2), a rotating shaft (3), a lower end cover (4), a lower end bearing (5), a fixed tube sheet (6), a shell (7), an outer layer crystallization tube (8), an inner layer crystallization tube (9), an annular plate (10), an inner scraper (11), an outer scraper (12), a knife holder (13), a refrigerant inlet pipe (14), a refrigerant outlet pipe (15), a delivery pipe (16), a water inlet pipe (17), a first outlet ice water pipe (18), a second outlet ice water pipe (19), and a variable frequency motor (20). The inner layer crystal tube (9) passes through and is fixed on the fixed tube sheet (6), and the upper end cover (2) is fixed at the top by screws, and a first outlet ice water pipe (18) is provided at the upper end of the side surface; the outer layer crystal tube (8) is sleeved outside the inner layer crystal tube (9) and fixed on the fixed tube sheet (6); the lower end of the outer layer crystal tube (8) and the lower end of the inner layer crystal tube (9) are welded and sealed by an annular plate (10); the fixed tube sheet (6) is provided with a refrigerant inlet pipe (14) and a refrigerant outlet pipe (15) located between the outer layer crystal tube (8) and the inner layer crystal tube (9); the delivery pipe (16) is connected to the refrigerant inlet pipe (14), and the number of the delivery pipes (16) is 12 and is evenly distributed between the outer layer crystal tube (8) and the inner layer crystal tube (9); the fixed tube sheet (6) and the lower end cover (4) are fixed to the shell (7) by screws; the lower end of the shell (7) is provided with a water inlet pipe (17), and the upper end of the side surface is provided with a second outlet ice water pipe (19).

[0013] The rotating shaft (3) is located in the inner crystal tube (9) and is fixed by an upper bearing (1) of an upper end cover (2) and a lower bearing (5) of a lower end cover (4); the inner scraper (11) is fixed on the rotating shaft (3) to peel off four ice crystals on the inner side of the inner crystal tube (9); the blade holder (13) is fixed on the rotating shaft (3) located at the lower end of the inner scraper (11); the outer scraper (12) is fixed on the blade holder (13) to peel off four ice crystals on the outer side of the outer crystal tube (8); the variable frequency motor (20) rotates the inner scraper (11) and the outer scraper (12) on the blade holder (13) via the rotating shaft (3).

[0014] The working principle of the utility model is as follows: when working, the refrigerant enters from the refrigerant inlet pipe (14) located between the outer layer crystal tube (8) and the inner layer crystal tube (9), is transported to the bottom between the outer layer crystal tube (8) and the inner layer crystal tube (9) through the transport pipe (16), absorbs heat and vaporizes before flowing out from the refrigerant outlet pipe (15) located at the upper end between the outer layer crystal tube (8) and the inner layer crystal tube (9); seawater enters from the water inlet pipe (17) at the lower end of the shell (7), and is respectively The inner side of the inner crystal tube (9) and the outer side of the outer crystal tube (8) exchange heat with the refrigerant to form ice, and the rotating shaft (3) drives the inner scraper (11) and the outer scraper (12) fixed on the blade holder (13) to peel off the ice crystals on the inner side of the inner crystal tube (9) and the ice crystals on the outer side of the outer crystal tube (8), respectively, and the obtained ice crystals flow out from the first outlet ice water pipe (18) at the upper end of the side of the inner crystal tube (9) and the second outlet ice water pipe (19) at the upper end of the side of the shell (7).

Claims

1. A small seawater freezing and desalination crystallizer, characterized in that: The invention comprises an upper end bearing (1), an upper end cover (2), a rotating shaft (3), a lower end cover (4), a lower end bearing (5), a fixed tube plate (6), a shell (7), an outer layer crystal tube (8), an inner layer crystal tube (9), an annular plate (10), an inner scraper (11), an outer scraper (12), a knife holder (13), a refrigerant inlet pipe (14), a refrigerant outlet pipe (15), a delivery pipe (16), a water inlet pipe (17), a first outlet ice water pipe (18), a second outlet ice water pipe (19), and a variable frequency motor (20). The inner layer crystal tube (9) passes through and is fixed on the fixed tube plate (6). The upper end is fixed to the upper end cover (2) by screws. The upper end of the side surface is provided with a first outlet ice water pipe (18). The outer layer crystal tube (8) is sleeved The outer side of the inner crystal tube (9) is fixed on the fixed tube sheet (6); the lower end of the outer crystal tube (8) and the lower end of the inner crystal tube (9) are welded and sealed by an annular plate (10); the fixed tube sheet (6) is provided with a refrigerant inlet pipe (14) and a refrigerant outlet pipe (15) located between the outer crystal tube (8) and the inner crystal tube (9); the delivery pipe (16) is connected to the refrigerant inlet pipe (14), the number of which is 12 and is evenly distributed between the outer crystal tube (8) and the inner crystal tube (9); the fixed tube sheet (6) and the lower end cover (4) are fixed to the shell (7) by screws; the lower end of the shell (7) is provided with a water inlet pipe (17), and the upper end of the side is provided with a second outlet ice water pipe (19).

2. A small seawater freezing and desalination crystallizer according to claim 1, characterized in that: The rotating shaft (3) is located in the inner crystal tube (9) and is fixed by an upper bearing (1) of an upper end cover (2) and a lower bearing (5) of a lower end cover (4); the inner scraper (11) is fixed on the rotating shaft (3) to peel off four ice crystals on the inner side of the inner crystal tube (9); the blade holder (13) is fixed on the rotating shaft (3) located at the lower end of the inner scraper (11); the outer scraper (12) is fixed on the blade holder (13) to peel off four ice crystals on the outer side of the outer crystal tube (8); the variable frequency motor (20) rotates the inner scraper (11) and the outer scraper (12) on the blade holder (13) via the rotating shaft (3).

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