Eight-effect three-section evaporator set for sodium aluminate solution

Abstract

The utility model relates to an eight-effect three-section evaporator set for sodium aluminate solution, which comprises an evaporator set consisting of a heating chamber, a vapor-liquid separation chamber, a self-evaporation flash evaporator and a preheater, the evaporator set adopts an eight-effect heating chamber and a separation chamber, adopts a six-stage self-evaporation flash evaporator, adopts a four-stage preheater and adopts a three-section feeding and discharging mode; the eight-effect three-section evaporator group formed by sequentially connecting the heating chamber and the vapor-liquid separation chamber forms a solution concentration loop and a vapor circulation loop; the solution concentration loop consists of a first concentration branch, a second concentration branch and a third concentration branch which are arranged in parallel; the steam circulation loop comprises an external live steam inlet pipeline for condensing live steam and recovering condensed water, a primary condensed water tank and a primary condensed water pump; the secondary condensate water tank and the secondary condensate water pump are used for condensing secondary steam and recovering condensate water; the steam generator has the advantages of reasonable structure, low steam consumption and production cost saving.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the concentration evaporation equipment technical field of sodium aluminate solution, concretely relates to sodium aluminate solution eight effect three section evaporator group. BACKGROUND

[0002] At present, in the production process of sodium aluminate in the world, the concentration evaporation of alumina production mother liquor sodium aluminate solution is carried out by using single section evaporator group not more than six effects, that is, three effect natural circulation evaporator group, four effect natural circulation evaporator group, five effect natural circulation evaporator group, five effect falling film evaporator group, six effect falling film evaporator group, etc. are generally used, and most of the old production lines adopt three effect, four effect, five effect evaporator group operation, and the newly built production line mostly adopts six effect evaporator group operation. The defects existing in the operation of these evaporator groups are as follows: high steam consumption (the steam consumption of three effect evaporator group operation reaches 0.5~0.6t steam / t water, the steam consumption of four effect evaporator group operation reaches 0.4~0.5t steam / t water, the steam consumption of five effect evaporator group operation reaches 0.35~0.4t steam / t water, and the steam consumption of six effect evaporator group operation reaches 0.28~0.33t steam / t water), resulting in high production cost. The evaporation energy consumption of alumina production mother liquor sodium aluminate solution accounts for one third of the production energy consumption of alumina, and reducing the evaporation energy consumption of solution can greatly reduce the production cost of alumina. Therefore, it is very necessary to provide a sodium aluminate solution eight effect three section evaporator group which is reasonable in structure, low in steam consumption and saves production cost. SUMMARY

[0003] The utility model discloses a kind of sodium aluminate solution eight effect three section evaporator groups to overcome the deficiencies of prior art, and the purpose is to provide a sodium aluminate solution eight effect three section evaporator group which is reasonable in structure, low in steam consumption and saves production cost.

[0004] The utility model discloses a kind of sodium aluminate solution eight effect three section evaporator groups, and the purpose is realized as follows: it includes by heating chamber, vapor-liquid separation chamber, self-evaporation flash evaporator, preheater the evaporator group, the evaporator group adopts eight effect heating chamber and separation chamber, adopts six level self-evaporation flash evaporator, adopts four level preheater, adopts three section feeding and discharging mode;The eight effect three section evaporator group that heating chamber and vapor-liquid separation chamber are sequentially connected together constitutes solution concentration loop and steam circulation loop;

[0005] The solution concentration loop is constituted by first concentration branch, second concentration branch and third concentration branch arranged side by side;

[0006] The steam circulation loop includes the external connection steam inlet pipeline for live steam, primary condensate tank and primary condensate pump for condensation and its condensate recovery;It also includes secondary condensate tank and secondary condensate pump for the condensation and its condensate recovery of secondary steam.

[0007] The first concentration branch is composed of a first-stage preheater, a second-stage preheater, a third-stage preheater, a fourth-stage preheater, a first heating chamber, a first-stage flash evaporator, a second-stage flash evaporator, a third-stage flash evaporator, a fourth-stage flash evaporator, a fifth-stage flash evaporator and a sixth-stage flash evaporator connected in series; the lower inlet of the preheater is connected with the raw liquid feeding pipeline, and the bottom outlet of the sixth-stage flash evaporator is connected with the product recovery pipeline.

[0008] The second concentration branch is composed of a second heating chamber, a third heating chamber, a fourth heating chamber, a fifth heating chamber, a sixth heating chamber, a second-stage flash evaporator, a third-stage flash evaporator, a fourth-stage flash evaporator, a fifth-stage flash evaporator and a sixth-stage flash evaporator connected in series; the lower inlet of the sixth heating chamber is connected with the raw liquid feeding pipeline, and the bottom outlet of the sixth-stage flash evaporator is connected with the product recovery pipeline.

[0009] The third concentration branch is composed of a seventh heating chamber and an eighth heating chamber connected in series; the lower inlet of the seventh heating chamber is connected with the raw liquid feeding pipeline, and the bottom outlet of the eighth heating chamber is connected with the product recovery pipeline.

[0010] A circulating feeding pipeline is arranged between the lower outlet and the top inlet of each heating chamber, and a circulating pump is arranged on the circulating feeding pipeline; a feeding pump is arranged on the material conveying pipeline between adjacent two heating chambers.

[0011] The external live steam feeding pipeline is connected with the steam inlet of the first heating chamber; the secondary steam outlets of the first to eighth heating chambers are connected with the corresponding vapor-liquid separation chambers, the secondary steam outlets of the first to eighth vapor-liquid separation chambers are respectively connected with the steam inlets of the next heating chambers, and the secondary steam pipelines of the first to fourth vapor-liquid separation chambers are also respectively connected with the heating steam inlets of the first to fourth preheaters.

[0012] The secondary steam outlets of the first to sixth flash evaporators are respectively connected with the second to eighth vapor-liquid separation chambers; a water cooler and a vacuum pump are connected to the steam outlet pipeline of the eighth vapor-liquid separation chamber.

[0013] The primary condensate water of the first heating chamber is collected through a primary condensate water tank and a primary condensate water pump; the secondary condensate water discharged from the second to eighth heating chambers is collected through a secondary condensate water tank and a secondary condensate water pump after being combined.

[0014] The first concentrated branch cycle mother liquor is preheated by a four-stage preheater, enters a I-effect heating chamber, and then enters a I-stage flash evaporator; the second concentrated branch cycle mother liquor directly enters a VI-effect heating chamber, and then enters a V-effect heating chamber, a IV-effect heating chamber, a III-effect heating chamber and a II-effect heating chamber in sequence; and the third concentrated branch cycle mother liquor directly enters a VII-effect heating chamber and then enters a VIII-effect heating chamber in downstream operation.

[0015] The first concentrated branch cycle mother liquor and the second concentrated branch cycle mother liquor are combined in a II-stage flash evaporator, and then enter a III-stage flash evaporator, a IV-stage flash evaporator, a V-stage flash evaporator and a VI-stage flash evaporator in sequence.

[0016] The utility model discloses a sodium aluminate solution eight-effect three-section evaporator group, in use, the utility model discloses an advantage lies in that eight-effect operation can make secondary steam utilize seven times, make steam consumption lower when concentrating sodium aluminate solution of alumina production mother liquor, three-section concentrated evaporation technology makes the material of entering I-effect heating chamber reduce, thereby reducing the consumption of live steam due to material heating, the utility model discloses adopt novel demister separator technology, make steam -liquid separation fully, do not exist liquid froth entrainment, run alkali situation, secondary condensate can return to boiler and be used repeatedly, the utility model discloses have the advantages of reasonable structure, low steam consumption, save production cost. BRIEF DESCRIPTION OF DRAWINGS

[0017] Fig. 1 It is the whole structure schematic diagram of utility model.

[0018] Fig. 2 It is the material flow chart of utility model.

[0019] Fig. 3 It is the steam flow chart of utility model.

[0020] In the diagram: 1a, Stage I heating chamber; 1b, Stage II heating chamber; 1c, Stage III heating chamber; 1d, Stage IV heating chamber; 1e, Stage V heating chamber; 1f, Stage VI heating chamber; 1g, Stage VII heating chamber; 1h, Stage VIII heating chamber; 2a, Stage I vapor-liquid separation chamber; 2b, Stage II vapor-liquid separation chamber; 2c, Stage III vapor-liquid separation chamber; 2d, Stage IV vapor-liquid separation chamber; 2e, Stage V vapor-liquid separation chamber; 2f, Stage VI vapor-liquid separation chamber; 2g, Stage VII vapor-liquid separation chamber; 2h, Stage VIII vapor-liquid separation chamber; 3a, Stage I flash evaporator; 3b, Stage II flash evaporator; 3c 1. Stage III flash evaporator 3d, Stage IV flash evaporator 3e, Stage V flash evaporator 3f, Stage VI flash evaporator 4a, Stage IV preheater 4b, Stage III preheater 4c, Stage II preheater 4d, Stage I preheater 5, Raw liquid feed pipeline 6, Finished product recovery pipeline 7, Circulating feed pipeline 8, Circulating pump 9, Feed pump 10, External live steam inlet pipeline 11, Water cooler 12, Vacuum pump 13, Primary condensate tank and primary condensate pump 14, Secondary condensate tank and secondary condensate pump 15, Discharge pump. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings. Example

[0022] like Figs. 1-3 As shown, the sodium aluminate solution eight-effect three-stage evaporator group includes an evaporator group consisting of a heating chamber, a vapor-liquid separation chamber, a self-evaporating flash evaporator, and a preheater. The evaporator group adopts an eight-effect heating chamber and a separation chamber, a six-stage self-evaporating flash evaporator, a four-stage preheater, and a three-stage inlet and outlet method. The eight-effect three-stage evaporator group, in which the heating chamber and the vapor-liquid separation chamber are connected in sequence, constitutes a solution concentration loop and a steam circulation loop.

[0023] The solution concentration circuit consists of a first concentration branch, a second concentration branch, and a third concentration branch arranged in parallel.

[0024] The steam circulation loop includes an external live steam inlet pipe 10 for condensing live steam and recovering its condensate, a primary condensate tank and a primary condensate pump 13; it also includes a secondary condensate tank and a secondary condensate pump 14 for condensing secondary steam and recovering its condensate.

[0025] The first concentration branch consists of a first-stage preheater 4d, a second-stage preheater 4c, a third-stage preheater 4b, a fourth-stage preheater 4a, a first-effect heating chamber 1a, a first-stage flash evaporator 3a, a second-stage flash evaporator 3b, a third-stage flash evaporator 3c, a fourth-stage flash evaporator 3d, a fifth-stage flash evaporator 3e, and a sixth-stage flash evaporator 3f connected in series. The lower inlet of the first-stage preheater 4d is connected to the raw liquid inlet pipeline 5, and the bottom outlet of the sixth-stage flash evaporator 3f is connected to the finished product recovery pipeline 6.

[0026] The second concentration branch is composed of the Ⅱ-effect heating chamber 1b, the Ⅲ-effect heating chamber 1c, the Ⅳ-effect heating chamber 1d, the Ⅴ-effect heating chamber 1e, the Ⅵ-effect heating chamber 1f, the second-stage flash evaporator 3b, the third-stage flash evaporator 3c, the fourth-stage flash evaporator 3d, the fifth-stage flash evaporator 3e and the sixth-stage flash evaporator 3f connected in series; the lower feeding port of the Ⅵ-effect heating chamber 1f is communicated with the raw solution feeding pipeline 5, and the bottom discharging port of the sixth-stage flash evaporator 3f is communicated with the finished product recovery pipeline 6.

[0027] The third concentration branch is composed of the Ⅶ-effect heating chamber 1g and the Ⅷ-effect heating chamber 1h connected in series; the lower feeding port of the Ⅶ-effect heating chamber 1g is communicated with the raw solution feeding pipeline 5, and the bottom discharging port of the Ⅷ-effect heating chamber 1h is communicated with the finished product recovery pipeline 6.

[0028] The lower discharging port and the top feeding port of each effect heating chamber are provided with a circulating feeding pipeline 7, and the circulating feeding pipeline 7 is provided with a circulating pump 8; the discharging conveying pipeline between the lower part of adjacent two heating chambers is provided with a material passing pump 9.

[0029] The first concentration branch circulating mother liquor is preheated by the four-stage preheater, then enters the Ⅰ-effect heating chamber 1a, and then enters the first-stage flash evaporator 3a; the second concentration branch circulating mother liquor directly enters the Ⅵ-effect heating chamber 1f, then enters the Ⅴ-effect heating chamber 1e, the Ⅳ-effect heating chamber 1d, the Ⅲ-effect heating chamber 1c and the Ⅱ-effect heating chamber 1b in sequence; the third concentration branch circulating mother liquor directly enters the Ⅶ-effect heating chamber 1g, then enters the Ⅷ-effect heating chamber 1h for downstream operation.

[0030] The first concentration branch circulating mother liquor and the second concentration branch circulating mother liquor are merged in the second-stage flash evaporator 3b, then enter the third-stage flash evaporator 3c, the fourth-stage flash evaporator 3d, the fifth-stage flash evaporator 3e and the sixth-stage flash evaporator 3f in sequence.

[0031] The utility model discloses a sodium aluminate solution eight effect three section evaporator group, in use, the advantage of the utility model lies in that eight effect operation can make seven times of secondary steam utilization, and the steam consumption is lower when the mother liquor sodium aluminate solution of alumina production is concentrated, three section type concentration evaporation technology makes the material entering Ⅰ effect heating chamber reduce, thereby reducing the consumption of live steam due to material heating, the utility model discloses a novel demisting separator technology, makes steam -liquid separation fully, and there is no liquid froth entrainment, and the alkali running condition does not exist, and secondary condensate can be returned to the boiler and repeatedly used, the utility model has the advantages of reasonable structure, low steam consumption and production cost saving. Embodiment

[0032] As Figs. 1-3The eight-effect three-stage evaporator group of sodium aluminate solution is shown, which comprises an evaporator group composed of a heating chamber, a vapor-liquid separation chamber, a self-evaporation flash evaporator and a preheater, the evaporator group adopts eight-effect heating chambers and separation chambers, six-stage self-evaporation flash evaporators, four-stage preheaters and three-stage feeding and discharging modes; the eight-effect three-stage evaporator group with the heating chamber and the vapor-liquid separation chamber connected in sequence forms a solution concentration loop and a steam circulation loop;

[0033] The solution concentration loop is composed of the first, second and third concentration branches arranged in parallel;

[0034] The steam circulation loop comprises an external live steam inlet pipeline 10 for live steam condensation and condensate water recovery, a primary condensate tank and a primary condensate pump 13, and further comprises a secondary condensate tank and a secondary condensate pump 14 for secondary steam condensation and condensate water recovery.

[0035] The external live steam inlet pipeline 10 is connected with the steam inlet of the I-effect heating chamber 1a; the secondary steam outlets of the I-effect to VIII-effect heating chambers are connected with the corresponding vapor-liquid separation chambers, i.e. the secondary steam outlet of the I-effect heating chamber 1a is connected with the I-effect vapor-liquid separation chamber 2a, the secondary steam outlet of the II-effect heating chamber 1b is connected with the II-effect vapor-liquid separation chamber 2b, and the secondary steam outlet of the VIII-effect heating chamber 1h is connected with the corresponding VIII-effect vapor-liquid separation chamber 2h;

[0036] The secondary steam outlet pipelines of the I-effect to VIII-effect vapor-liquid separation chambers are respectively connected with the steam inlets of the next-effect heating chambers, i.e. the secondary steam outlet pipeline of the I-effect vapor-liquid separation chamber 2a is connected with the steam inlet of the II-effect heating chamber 1b, the secondary steam outlet pipeline of the II-effect vapor-liquid separation chamber 2b is connected with the steam inlet of the III-effect heating chamber 1c, and the secondary steam outlet pipeline of the VII-effect vapor-liquid separation chamber 2g is connected with the steam inlet of the VIII-effect heating chamber 1h;

[0037] Meanwhile, the secondary steam pipelines of the I-effect to IV-effect vapor-liquid separation chambers are also respectively connected with the heating steam inlets of the IV-effect to I-effect preheaters, i.e. the secondary steam outlet pipeline of the I-effect flash evaporator 3a is connected with the II-effect vapor-liquid separation chamber 2b, the secondary steam outlet pipeline of the II-effect flash evaporator 3b is connected with the III-effect vapor-liquid separation chamber 2c, the secondary steam outlet pipeline of the III-effect flash evaporator 3c is connected with the IV-effect vapor-liquid separation chamber 2d, the secondary steam outlet pipeline of the IV-effect flash evaporator 3d is connected with the V-effect vapor-liquid separation chamber 2e, the secondary steam outlet pipeline of the V-effect flash evaporator 3e is connected with the VI-effect vapor-liquid separation chamber 2f, and the secondary steam outlet pipeline of the VI-effect flash evaporator 3f is connected with the VII-effect vapor-liquid separation chamber 2g;

[0038] That is, the secondary steam outlet pipelines of the I-VI flash evaporators are connected with the II-VIII separation chambers respectively; the steam outlet pipeline of the VIII separation chamber 2h is connected with a water cooler 11 and a vacuum pump 12.

[0039] The primary condensate water of the I heating chamber la is collected by a primary condensate water tank and a primary condensate water pump 13; the secondary condensate water of the II, III, IV, V, VI, VII and VIII heating chambers lb, lc, ld, le, lf, lg and lh is collected by a secondary condensate water tank and a secondary condensate water pump 14 after being combined.

[0040] In the embodiment, specifically, when working, the circulating mother liquor with a concentration of about 160 g / L is introduced into the I-stage preheater 4d, the VI heating chamber lf and the VII heating chamber lg according to the flow of the three concentration branches through the raw solution feeding pipeline 5; the raw solution introduced into the VII heating chamber lg is heated and evaporated once in the VII heating chamber lg, then introduced into the VIII heating chamber lh to be heated and evaporated again, and the concentrated solution with a concentration of about 220 g / L is obtained;

[0041] The raw solution introduced into the VI heating chamber lf is sequentially heated and evaporated in the VI, V, IV, III, II and I heating chambers lf, le, ld, lc, lb and la, then sequentially introduced into the II, III, IV, V, VI and I flash evaporators 3b, 3c, 3d, 3e, 3f and 3a through the solution pump 9 to be concentrated by self-evaporation, and the concentrated solution with a concentration of about 250 g / L is obtained;

[0042] The raw solution introduced into the I-stage preheater 4d is sequentially preheated in the I, II, III and IV-stage preheaters 4d, 4c, 4b and 4a, evaporated in the I heating chamber la, and then sequentially concentrated by self-evaporation in the I, II, III, IV, V and VI flash evaporators 3a, 3b, 3c, 3d, 3e and 3f, and the concentrated solution with a concentration of about 250 g / L is obtained;

[0043] Finally, the concentrated solutions obtained by the first, second and third concentration branches are combined and collected by the discharge pump 15, as shown in FIG. 5. Fig. 1 , 2

[0044] ​Meanwhile, the hot steam of 158 DEG C introduced by the high-temperature steam source firstly enters the I-effect heating chamber 1a to heat and concentrate the solution in the I-effect heating chamber 1a, the secondary steam evaporated from the I-effect heating chamber 1a enters the II-effect heating chamber 1b and the IV-stage preheater 4a through the I-effect vapor-liquid separation chamber 2a, the secondary steam evaporated from the II-effect heating chamber 1b enters the III-effect heating chamber 1c and the III-stage preheater 4b through the II-effect vapor-liquid separation chamber 2b, the secondary steam evaporated from the III-effect heating chamber 1c enters the IV-effect heating chamber 1d and the II-stage preheater 4c through the III-effect vapor-liquid separation chamber 2c, the secondary steam evaporated from the IV-effect heating chamber 1d enters the V-effect heating chamber 1e and the I-stage preheater 4d through the IV-effect vapor-liquid separation chamber 2d, and so on, the secondary steam evaporated from the VII-effect heating chamber 1g enters the VIII-effect heating chamber 1h through the VII-effect vapor-liquid separation chamber 2g, and the secondary steam evaporated from the VIII-effect heating chamber 1h (the temperature can be reduced to 50 DEG C) enters the water cooler 11 to be cooled through the VIII-effect vapor-liquid separation chamber 2h.

[0045] The secondary steam from the I-stage flash evaporator 3a enters the II-effect vapor-liquid separation chamber 2b, the secondary steam from the II-stage flash evaporator 3b enters the III-effect vapor-liquid separation chamber 2c, the secondary steam from the III-stage flash evaporator 3c enters the IV-effect vapor-liquid separation chamber 2d, the secondary steam from the IV-stage flash evaporator 3d enters the V-effect vapor-liquid separation chamber 2e, the secondary steam from the V-stage flash evaporator 3e enters the VI-effect vapor-liquid separation chamber 2f, and the secondary steam from the VI-stage flash evaporator 3f enters the VII-effect vapor-liquid separation chamber 2g, as shown in Fig. Fig. 1 、 3

[0046] In summary, the eight-effect three-stage evaporator group for the sodium aluminate solution of the alumina production mother liquor has the steam consumption of 0.16 tons of steam per ton of water, compared with the six-effect single-stage evaporator group, 0.14 tons of steam can be saved for evaporating 1 ton of water, the national alumina production capacity is 5000 million tons, the technology is popularized in the country, 3000 million tons of steam can be saved annually, 600 million tons of power coal are saved, and more than 4 billion yuan of economic benefits can be generated annually.

[0047] The eight-effect three-stage evaporator group for the sodium aluminate solution has the advantages that the eight-effect operation can make the secondary steam be utilized for seven times, the steam consumption is lower when the sodium aluminate solution of the alumina production mother liquor is concentrated, the three-stage type concentration and evaporation technology reduces the material entering the I-effect heating chamber, thereby reducing the consumption of the live steam caused by the material temperature rise, the novel defoaming separator technology is adopted, the vapor-liquid separation is sufficient, there is no liquid foam entrainment and alkali running, the secondary condensed water can be returned to the boiler for repeated use, and the eight-effect three-stage evaporator group for the sodium aluminate solution has the advantages of reasonable structure, low steam consumption and production cost saving.​

Claims

1. An eight-effect, three-stage evaporator assembly for sodium aluminate solution, comprising an evaporator assembly consisting of a heating chamber, a vapor-liquid separation chamber, a self-evaporating flash evaporator, and a preheater, characterized in that: The evaporator group adopts an eight-effect heating chamber and a separation chamber, a six-stage self-evaporating flash evaporator, a four-stage preheater, and a three-stage inlet and outlet method; the eight-effect three-stage evaporator group, in which the heating chamber and the vapor-liquid separation chamber are connected in sequence, constitutes a solution concentration loop and a steam circulation loop. The solution concentration circuit consists of a first concentration branch, a second concentration branch, and a third concentration branch arranged in parallel. The steam circulation loop includes an external live steam inlet pipe for condensing live steam and recovering its condensate, a primary condensate tank, and a primary condensate pump; it also includes a secondary condensate tank and a secondary condensate pump for condensing secondary steam and recovering its condensate.

2. The sodium aluminate solution eight-effect three-stage evaporator group according to claim 1, characterized in that: The first concentration branch consists of a first-stage preheater, a second-stage preheater, a third-stage preheater, a fourth-stage preheater, a first-effect heating chamber, a first-stage flash evaporator, a second-stage flash evaporator, a third-stage flash evaporator, a fourth-stage flash evaporator, a fifth-stage flash evaporator, and a sixth-stage flash evaporator connected in series. The lower inlet of the preheater is connected to the raw liquid inlet pipeline, and the bottom outlet of the sixth-stage flash evaporator is connected to the finished product recovery pipeline.

3. The sodium aluminate solution eight-effect three-stage evaporator group according to claim 2, characterized in that: The second concentration branch consists of a series of heating chambers connected in series: a second-effect heating chamber, a third-effect heating chamber, a fourth-effect heating chamber, a fifth-effect heating chamber, a sixth-effect heating chamber, a second-stage flash evaporator, a third-stage flash evaporator, a fourth-stage flash evaporator, a fifth-stage flash evaporator, and a sixth-stage flash evaporator. The lower inlet of the sixth-effect heating chamber is connected to the raw liquid feed pipeline, and the bottom outlet of the sixth-stage flash evaporator is connected to the finished product recovery pipeline.

4. The sodium aluminate solution eight-effect three-stage evaporator group according to claim 3, characterized in that: The third concentration branch consists of a VII-effect heating chamber and a VIII-effect heating chamber connected in series; the lower inlet of the VII-effect heating chamber is connected to the raw liquid inlet pipeline, and the bottom outlet of the VIII-effect heating chamber is connected to the finished product recovery pipeline.

5. The sodium aluminate solution eight-effect three-stage evaporator group according to claim 4, characterized in that: A circulating feed pipe is provided between the lower discharge port and the top feed port of each heating chamber, and a circulating pump is provided on the circulating feed pipe; a feed pump is provided on the material conveying pipeline between two adjacent heating chambers.

6. The sodium aluminate solution eight-effect three-stage evaporator group according to claim 5, characterized in that: The external live steam inlet pipe is connected to the steam inlet of the first-effect heating chamber; the secondary steam outlet of the first-eighth-effect heating chambers is connected to their corresponding vapor-liquid separation chambers, and the secondary steam outlet pipes of the first-eighth-effect vapor-liquid separation chambers are respectively connected to the steam inlet of their next-next-effect heating chamber. At the same time, the secondary steam pipes of the first-fourth-effect vapor-liquid separation chambers are also respectively connected to the heating steam inlet of the fourth-first-stage preheater.

7. The sodium aluminate solution eight-effect three-stage evaporator group according to claim 6, characterized in that: The secondary steam outlet pipelines of the I-VI stage flash evaporators are respectively connected to the II-VIII effect separation chambers; a water cooler and a vacuum pump are connected to the steam outlet pipeline of the VIII effect vapor-liquid separation chamber.

8. The sodium aluminate solution eight-effect three-stage evaporator assembly according to claim 7, characterized in that: The primary condensate from the I-effect heating chamber is collected via a primary condensate tank and a primary condensate pump; the secondary condensate from the II-effect, III-effect, IV-effect, V-effect, VI-effect, VII-effect, and VIII-effect heating chambers is combined and collected via a secondary condensate tank and a secondary condensate pump.

9. The sodium aluminate solution eight-effect three-stage evaporator assembly according to claim 4, characterized in that: The mother liquor circulating in the first concentration branch is preheated by a four-stage preheater and then enters the first-effect heating chamber, and then enters the first-stage flash evaporator; the mother liquor circulating in the second concentration branch directly enters the sixth-effect heating chamber, and then sequentially enters the fifth-effect heating chamber, the fourth-effect heating chamber, the third-effect heating chamber, and the second-effect heating chamber. The mother liquor circulating in the third concentration branch directly enters the VII-effect heating chamber and then enters the VIII-effect heating chamber for co-current operation.

10. The sodium aluminate solution eight-effect three-stage evaporator assembly according to claim 9, characterized in that: The mother liquor from the first and second concentration branches enters the stage II flash evaporator and then merges into the stage III, stage IV, stage V, and stage VI flash evaporators in sequence.

Images