A black liquor bellows tube super-efficient evaporation device and process

Abstract

The present invention provides a black liquor corrugated tube super-efficiency evaporation device and process, which relates to the field of papermaking chemical waste liquid recovery, including 1-n effect evaporators, 1-n level intermediate liquid preheaters, 5-n level black liquor preheaters, steam spray extractors, partition condensers, vacuum pumps, black liquor feed pumps, intermediate liquid pumps, concentrated liquid tanks, concentrated liquid pumps, condensate tanks and condensate pumps. The present invention is an evaporation device with super-multiple effects and ultra-low steam consumption designed for papermaking black liquor. According to the characteristics of high specific gravity and high viscosity of black liquor concentrate, a special evaporation process of black liquor in the inter-effect direction and different preheating processes of black liquor and intermediate liquid are designed, and then steam return from the steam spray extractor is added, so that the steam consumption per ton of evaporation of black liquor reaches the most advanced level of black liquor evaporation. In addition, a high-efficiency corrugated tube evaporator suitable for super-efficiency evaporation of black liquor and evaporation and concentration of high solid content is designed.

Description

Technical Field

[0001] The invention relates to the field of papermaking chemical waste liquid recovery, and in particular to a black liquor bellows super-efficient evaporation device and process. Background Art

[0002] The wastewater produced by the caustic soda and kraft pulping processes in the papermaking industry contains a large amount of lignin, which is dark brown, so it is called black liquor. Black liquor contains a lot of solid phase, high concentration, high boiling point, easy to scale and clog. In recent years, multi-effect evaporation and plate evaporation have been introduced to treat black liquor, and the production situation has improved. At present, the multi-effect evaporation of black liquor has increased from 4 effects to 5 effects, but the steam consumption is still high. The steam consumption per ton of evaporation is 0.3167 for four-effect evaporation and 0.2478 for five-effect evaporation plus preheating. The newly invented super-efficiency evaporation technology in the past two years all adopts the downstream evaporation process from 1 effect to n effects, and the preheating is also a single component preheating process. This downstream evaporation process and the single component preheating process are not suitable for the characteristics of black liquor material evaporation. The current black liquor evaporation equipment generally uses tube-in-tube falling film evaporation and plate heat exchanger falling film evaporation. The plate heat exchanger falling film evaporation does not take advantage of the low-speed turbulence of the plate heat exchanger, has a low heat transfer coefficient, and the heat exchanger is huge, which is not advanced in practice. In summary, there is a need to invent a black liquor evaporation device which can significantly reduce steam consumption, is not prone to scaling, has a high heat transfer coefficient and can increase the evaporation concentration of black liquor. Summary of the invention

[0003] The invention provides a black liquor corrugated tube super-efficiency evaporation device and process, which solves the problems of high steam consumption, low heat transfer efficiency and easy scaling of the existing black liquor evaporation device.

[0004] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0005] A black liquor bellows super-efficiency evaporation device, comprising 1 to n-effect evaporators, 1 to n-stage heaters, 1 to n-stage intermediate liquid preheaters, 5 to n-stage black liquor preheaters, condensers, vacuum pumps, black liquor feed pumps, intermediate liquid pumps, condensate tanks, condensate pumps, concentrated liquid tanks and concentrated liquid pumps, wherein n is an integer of 7 to 10;

[0006] The liquid inlet of the n-stage black liquor preheater is connected to the outlet of the black liquor feed pump. With the flow direction of the black liquor as the front, in the 5-n-stage black liquor preheaters, the outlet of the n-stage black liquor preheater is connected to the inlet of the n-1-stage black liquor preheater, the outlet of the latter-stage black liquor preheater is connected to the inlet of the previous-stage black liquor preheater, the outlet of the 5-stage black liquor preheater is connected to the inlet of the 4-effect evaporator, the outlet of the 4-effect evaporator is connected to the inlet of the 5-effect evaporator, and so on. The liquid outlet is connected to the inlet of the intermediate liquid pump; the outlet of the intermediate liquid pump is connected to the liquid inlet of the n-stage intermediate liquid preheater; the liquid outlet of the n-stage intermediate liquid preheater is connected to the liquid inlet of the n-1-stage intermediate liquid preheater; the liquid outlet of the 1-stage intermediate liquid preheater is connected to the liquid inlet of the 1-effect evaporator; the liquid outlet of the 1-effect evaporator is connected to the liquid inlet of the 2-effect evaporator, the liquid outlet of the 2-effect evaporator is connected to the liquid inlet of the 3-effect evaporator, and the liquid outlet of the 3-effect evaporator is connected to the liquid inlet of the concentrated liquid storage tank;

[0007] In the 1-3 effect evaporators, the secondary steam outlet of the 1 effect is connected to the low-pressure steam inlet of the steam ejector, the heater inlet of the 2 effect evaporator, and the steam inlet of the 2nd intermediate liquid preheater; the secondary steam outlets of the 2 effect evaporators and the 3 effect evaporators are respectively connected to the heater steam inlet of the 3 effect evaporator and the 4 effect evaporator and the steam inlet of the 3rd intermediate liquid preheater and the 4th intermediate liquid preheater; the secondary steam outlets of the 4-n-1 effect evaporators are respectively connected to the heater steam inlet of the 5-n effect evaporators and the steam inlet of the 5-n black liquor preheater and the 5-n intermediate liquid preheater; the secondary steam outlet of the n effect evaporator is connected to the steam inlet of the partition condenser; the non-condensable gas outlet of the partition condenser is connected to the vacuum pump;

[0008] The condensed water outlet of the heater of the 1st-effect evaporator is connected to the condensed water inlet of the 1st-level intermediate liquid preheater, and the condensed water outlets of the 1st-level intermediate liquid preheater, the 2nd-level intermediate liquid preheater and the heater of the 2nd-effect evaporator are all connected to the flash condensed water inlet of the heater of the 3rd-effect evaporator; the condensed water outlet of the heater of the 3rd-effect evaporator and the 3rd-level intermediate liquid preheater are connected to the flash condensed water inlet of the heater of the 4th-effect evaporator; the condensed water outlet of the heater of the 4th-effect evaporator and the 4th-level intermediate liquid preheater are connected to the flash condensed water inlet of the heater of the 5th-effect evaporator; the condensed water outlet of the heater of the 5th-n-1st-effect evaporator, the 5th-n-1st-level black liquor preheater and the 5th-n-1st-level intermediate liquid preheater are connected to the flash condensed water inlet of the heater of the 6th-nth-effect evaporator; the condensed water outlet of the heater of the nth-effect evaporator, the nth-level black liquor preheater and the nth-level intermediate liquid preheater are connected to the inlet of the condensed water tank.

[0009] Preferably, the condenser is a corrugated tube partition condenser or a falling film condenser.

[0010] Preferably, the boiler steam is connected to a steam jet extractor through a pipeline, and the low-pressure steam inlet of the steam jet extractor is connected to the secondary steam outlet of the first-effect evaporator.

[0011] Preferably, the heater of the evaporator is a short-tube corrugated tube structure, and the black liquor preheater and the intermediate liquid preheater are long-tube corrugated tube structures.

[0012] A black liquor bellows super-efficient evaporation process, implemented based on any one of the above devices, including a material flow process, a steam flow process and a condensed water flow process;

[0013] The material flow process comprises: black liquor enters a black liquor feed pump from outside the process, and then countercurrently passes through n to 5 levels of black liquor preheaters in sequence, the black liquor in the 5-level black liquor preheater enters a 4-effect evaporator, and then flows downstream to an n-effect evaporator, the black liquor in the n-effect evaporator enters an intermediate liquid pump, and then countercurrently passes through n to 1-level intermediate liquid preheaters in sequence, the black liquor in the 1-level intermediate liquid preheater enters a 1-effect evaporator, and then flows downstream to a 3-effect evaporator, the concentrated black liquor in the 3-effect evaporator enters a concentrated liquid storage tank, the concentrated liquid storage tank is connected to a pipeline for discharging concentrated black liquor, and the black liquor is discharged from the process;

[0014] The steam process technology comprises: a steam source enters a first-effect evaporator to supply heat to the first-effect evaporator, the secondary steam discharged from the first-effect evaporator supplies heat to a heater and a second-stage intermediate liquid preheater of a second-effect evaporator, the secondary steam discharged from the second-effect evaporator supplies heat to a heater and a third-stage intermediate liquid preheater of a third-effect evaporator, the secondary steam discharged from the third-effect evaporator supplies heat to a heater and a fourth-stage intermediate liquid preheater of a fourth-effect evaporator, the secondary steam discharged from 4 to n-1-effect evaporators supplies heat to heaters, fifth to n-stage black liquor preheaters and fifth to n-stage intermediate liquid preheaters of fifth to n-effect evaporators respectively, the secondary steam discharged from the n-effect evaporator enters a partition condenser to be condensed into condensed water, and the non-condensable gas in the partition condenser is discharged by a vacuum pump;

[0015] The condensed water process technology includes: condensed water from the heater of the 1st effect evaporator enters the 1st level intermediate liquid preheater, condensed water from the 1st level intermediate liquid preheater, the 2nd level intermediate liquid preheater and the heater of the 2nd effect evaporator enters the heater of the 3rd effect evaporator for flashing, the heater of the 3rd effect evaporator and the condensed water from the 3rd level intermediate liquid preheater enters the heater of the 4th effect evaporator for flashing, the heater of the 4th effect evaporator and the condensed water from the 4th level intermediate liquid preheater enters the heater of the 5th effect evaporator for flashing, the heater of 5 to n-1 effect evaporators, 5 to n-1 level black liquor preheaters and 5 to n-1 level intermediate liquid preheaters enter the heater of 6 to n effect evaporators for flashing, the heater of the n effect evaporator, the nth level black liquor preheater and the nth level intermediate liquid preheater enter the condensed water tank, and the condensed water in the condensed water tank is passed to the condensed water pipe outside the process through a condensed water pump.

[0016] The beneficial effects of the present invention are:

[0017] The present invention is an evaporation device with ultra-high number of effects and ultra-low steam consumption designed for papermaking black liquor, which is characterized by ultra-efficient evaporation with "small temperature difference heat transfer and small temperature difference loss". According to the characteristics of high specific gravity and high viscosity of black liquor concentrate, the evaporation process of black liquor flowing to 4-5-6-7-8-9-1-2-3 between effects is designed; the preheating process of black liquor flowing to 9-8-7-6-5 and the preheating process of intermediate liquid flowing to 9-8-7-6-5-4-3-2-1. In the last 6 effects of the 9-effect evaporation, low-concentration and medium-concentration black liquor are evaporated at low temperature, and high-concentration solution is evaporated at high temperature in the first 1-3 effects. The 9-effect evaporation with ultra-high number of effects, and the return steam of the steam injection extraction device are added, so that the steam consumption per ton of evaporation of black liquor reaches the most advanced level of black liquor evaporation of 0.1276, which is nearly half lower than the 0.2487 in the black liquor evaporation calculation model paper published recently, thereby achieving the economic effect of reducing steam consumption by nearly 50%;

[0018] The present invention designs a preheating process of two components, a black liquor preheater and an intermediate liquid preheater, so that the preheating effect is better and the economic effect of significantly reducing steam consumption is achieved;

[0019] The present invention designs a corrugated tube short tube evaporator for black liquor evaporation, replacing the existing falling film evaporator and plate type falling film evaporator, and greatly improving the heat transfer coefficient. The short tube structure is to reduce the temperature rise of the black liquor in the heater, thereby reducing the heat transfer temperature difference loss caused by the temperature rise. The corrugated tube short tube evaporator can also solve the problem that the plate type falling film evaporator is easy to scale and needs frequent car washing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a flow chart of super-efficient evaporation of black liquor according to the present invention.

[0022] In the figure: V1~V9, 1st~9th effect evaporation chamber; H1~H9, 1st~9th effect heater; XB1~XB9, 1st~9th effect circulation pump; A5~A9, 5th~9th level black liquor preheater; B1~B9, 1st~9th level intermediate liquid preheater; ZB, vacuum pump; ZP, steam jet extractor; HB1, black liquor feed pump; HB2, intermediate liquid pump; N G , condensate tank; Y G, concentrate tank; NB, condensate pump; YB, concentrate pump; N, partition condenser. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, 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 part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1

[0026] like Figure 1 As shown, the black liquor bellows super-efficiency evaporation device includes 1 to 9-effect evaporators, 5 to 9-stage black liquor preheaters A5 to A9, 1 to 9-stage intermediate liquid preheaters B1 to B9, partition condenser N, vacuum pump ZB, concentrated liquid tank Y G , Concentrate pump YB, Condensate tank N G , condensate pump NB;

[0027] The 1st to 9th effect evaporators are composed of corrugated short tube heaters H1 to H9, evaporation chambers V1 to V9, circulation pumps XB1 to XB9 and circulation pipelines.

[0028] The liquid inlet of the 9-stage black liquor preheater A9 is connected to the outlet of the black liquor feed pump HB1. With the black liquor flow direction as the front, in the 5-9-stage black liquor preheaters, the liquid outlet of the latter black liquor preheater is connected to the liquid inlet of the previous black liquor preheater, the liquid outlet of the 9-stage black liquor preheater A9 is connected to the liquid inlet of the 8-stage black liquor preheater A8, and so on. The liquid outlet of the 5-stage black liquor preheater A5 is connected to the liquid inlet of the 4th-effect evaporator V4.

[0029] The liquid inlet of the 9-stage black liquor preheater is connected to the outlet of the black liquor feed pump. With the direction of black liquor flow as the front, in the 5-9-stage black liquor preheaters, the outlet of the 9-stage black liquor preheater is connected to the inlet of the 8-stage black liquor preheater, and the liquid outlet of the latter stage black liquor preheater is connected to the liquid inlet of the former stage black liquor preheater. The outlet of the 5-stage black liquor preheater is connected to the liquid inlet of the 4-effect evaporator, the liquid outlet of the 4-effect evaporator is connected to the liquid inlet of the 5-effect evaporator, and so on, the liquid outlet of the 9-effect evaporator is connected to the inlet of the intermediate liquid pump; the outlet of the intermediate liquid pump is connected to the liquid inlet of the 9-stage intermediate liquid preheater; the liquid outlet of the 9-stage intermediate preheater is connected to the liquid inlet of the 8-stage intermediate liquid preheater; the liquid outlet of the 1-stage intermediate liquid preheater is connected to the liquid inlet of the 1-effect evaporator; the liquid outlet of the 1-effect evaporator is connected to the liquid inlet of the 2-effect evaporator, the liquid outlet of the 2-effect evaporator is connected to the liquid inlet of the 3-effect evaporator, and the liquid outlet of the 3-effect evaporator is connected to the liquid inlet of the concentrated liquid storage tank.

[0030] The boiler steam passes through the steam jet extractor ZP to extract part of the secondary steam from the 1st effect evaporation chamber V1 for heating steam, thus increasing the evaporation capacity of the 1st effect evaporation chamber V1. The secondary steam outlet of the 1st effect evaporation chamber V1 is connected to the steam inlet of the 2nd effect heater H2 and the 2nd level intermediate liquid preheater B2; the secondary steam outlet of the 2nd effect evaporation chamber V2 is connected to the steam inlet of the 3rd effect heater H3 and the 3rd level intermediate liquid preheater B3; the secondary steam outlet of the 3rd effect evaporation chamber V3 is connected to the steam inlet of the 4th effect heater H4 and the 4th level intermediate liquid preheater B4; the secondary steam outlet of the 4th effect evaporation chamber V4 is connected to the steam inlet of the 5th effect heater H5 and the 5th level raw material preheater A5 and the 5th level intermediate liquid preheater B5; the secondary steam outlet of the 5th effect evaporation chamber V5 is connected to the steam inlet of the 6th effect heater H6 and the 6th level black liquor preheater A6, The steam inlet of the 6th-stage intermediate liquid preheater B6 is connected; the secondary steam outlet of the 6th-effect evaporation chamber V6 is connected to the steam inlet of the 7th-effect heater H7 and the steam inlets of the 7th-stage black liquor preheater A7 and the 7th-stage intermediate liquid preheater B7; the secondary steam outlet of the 7th-effect evaporation chamber V7 is connected to the steam inlet of the 8th-effect heater H8 and the steam inlet of the 8th-stage black liquor preheater A8 and the intermediate liquid preheater B8; the secondary steam outlet of the 8th-effect evaporation chamber V8 is connected to the steam inlet of the 9th-effect heater H9 and the steam inlet of the 9th-stage black liquor preheater A9 and the 9th-stage intermediate liquid preheater B9; the secondary steam outlet of the 9th-effect evaporator V9 is connected to the steam inlet of the partition condenser N.

[0031] The condensate outlet of the 1st effect heater H1 is connected to the condensate inlet of the 1st level intermediate liquid preheater B1; the condensate outlets of the 1st level intermediate liquid preheater B1 and the 2nd level intermediate liquid preheater B2 are connected to the condensate outlet of the 2nd effect heater H2, and then connected to the flash condensate inlet of the 3rd effect heater H3; the condensate outlet of the 3rd effect heater H3 is connected to the condensate outlet of the 3rd level intermediate liquid preheater B3, and then connected to the flash condensate inlet of the 4th effect heater H4; the condensate outlet of the 4th effect heater H4 is connected to the condensate outlet of the 4th level intermediate liquid preheater B4, and then connected to the condensate outlet of the 5th effect heater The flash condensate inlet of H5 is connected; the condensate outlet of the 5-effect heater H5 is connected to the condensate outlet of the 5-level raw material preheater A5 and the 5-level intermediate liquid preheater B5, and then connected to the flash condensate inlet of the 6-effect heater H6; and so on, the condensate outlet of the 8-effect heater H8 is connected to the condensate outlet of the 8-level black liquor preheater A8 and the intermediate liquid preheater B8, and then connected to the flash condensate inlet of the 9-effect heater H9; the condensate outlet of the 9-effect heater is connected to the condensate outlet of the 9-level black liquor preheater A9 and the 9-level intermediate liquid preheater B9, and then connected to the condensate tank N G Water inlet connection; condensate tank N G The water outlet is connected to the water inlet of the condensate pump NB, and the water outlet of the condensate pump is connected to the condensate pipe leading to the outside of the process.

[0032] The present invention designs a nine-effect evaporation with "small temperature difference heat transfer and small temperature difference loss" for black liquor evaporation, and according to the characteristics of high specific gravity and high viscosity of black liquor concentrate, designs the evaporation process of black liquor flowing to 4-5-6-7-8-9-1-2-3 between effects, the preheating process of raw black liquor flowing to 9-8-7-6-5 and the preheating process of intermediate concentrated liquid flowing to 9-8-7-6-5-4-3-2-1, and adds a steam-spray-return-absorption process.

[0033] This process is the key technology for black liquor evaporation to achieve the lowest steam consumption and the required evaporation concentration: low-concentration and medium-concentration black liquor are evaporated at low temperature in the last 6 effects of 9-effect evaporation, and high-concentration solution is evaporated at high temperature in the first 1-3 effects. 9-effect evaporation, and increasing the return steam of the steam injection steam extractor, can make the steam consumption per ton of evaporation of black liquor reach the most advanced level of black liquor evaporation of 0.1276, and the black liquor concentration can reach 49-60%.

[0034] Designing a corrugated tube short tube evaporator to replace the current falling film evaporator and plate type falling film evaporator can double the heat transfer coefficient of the heat exchanger. Designing a short tube structure evaporator can reduce the temperature rise of the black liquor in the heater, thereby reducing the heat transfer temperature difference loss caused by the temperature rise. The corrugated tube short tube evaporator can also solve the problem of the plate type falling film evaporator being easy to scale and requiring frequent car washing.

[0035] The present invention uses a corrugated tube partition condenser to condense the secondary steam of 9-effect evaporation, which improves the heat transfer capacity by 1-2 times compared with the existing partition condenser.

[0036] The heaters of all evaporators of the present invention and the A and B series preheaters all use bellows heat exchangers, so that the heat transfer coefficient can reach 1200-2500 kcal / m2h℃, which is about 50% higher than that of the current black liquor evaporation device.

[0037] In this embodiment:

[0038] Calculation of process parameters for super-efficient evaporation of 100 tons of black liquor:

[0039] The black liquor before concentration has a specific gravity of 9°Be′ (15°C), a concentration of 11.29%, a specific heat of 0.9 kcal / kg°C, a feed flow rate of 100 t / h, and a feed temperature of 50°C.

[0040] The raw black liquor preheating series is preheated by A9, A8, A7, A6, and A5, with the preheating temperature at 83.3°C, and then enters the fourth effect evaporation;

[0041] The cumulative evaporation capacity of 4-9 effects is 46718.2kg / h, and the flow rate of the intermediate liquid discharged from the 9th effect is 100000-46718.2=53281.8kg / h,

[0042] The concentration of the intermediate liquid in the 9th effect row is 21.29%.

[0043] After the intermediate liquid preheating series B9-B1, the preheating temperature is 123℃,

[0044] After 1-2-3 effect evaporation, the cumulative evaporation capacity of 1-3 effect is 30357.28kg / h.

[0045] Total evaporation capacity W = 100000 (1-11.29 / 49.25) = 77076 kg / h.

[0046] The third-effect evaporator discharges 22924 kg / h of black liquor concentrate with a specific gravity of 35° Be′ (15° C.) and a concentration of 49.25%.

[0047] The secondary steam of the 9th effect at 38.3℃ enters the bellows condenser and is condensed by cooling water at room temperature.

[0048] Process parameter table of 100-ton black liquor super-efficient evaporation device:

[0049]

[0050] Device cost and economic benefits:

[0051] (1) The theoretical steam-water ratio of the existing advanced black liquor five-effect evaporation mathematical model is 0.2487.

[0052] Steam saved per hour compared with this model: 77 (0.2478-0.1276) = 9.255t / h,

[0053] Annual savings: 8000*9.255=74040t / a. Steam cost per ton is 150 yuan.

[0054] Annual steam cost savings: 74040*150=11.106 million yuan

[0055] The extra electricity consumption is (9*22-5*12) 0.85 = 138 kWh, and the extra electricity consumption per year is 138*8000 = 1.904 million kWh, and the cost per kWh is 0.65 yuan.

[0056] The additional electricity consumption per year is 190.4*0.65=1.2376 million yuan.

[0057] Excluding the reduction in circulating water consumption, the net energy saving benefit is 1110.6-123.76=9868400 yuan

[0058] (2) Installation cost: about 9 million yuan (full set of equipment)

[0059] (3) The steam savings within one year can recover the investment.

[0060] Example 2

[0061] A black liquor corrugated tube super-efficient evaporation process, implemented based on the device described in Example 1, characterized in that: it includes a material flow process, a steam flow process and a condensed water flow process;

[0062] The material flow process includes: black liquor enters the black liquor feed pump HB1 from outside the process, and then countercurrently passes through the 9-5 level black liquor preheaters A9-A5 in sequence, the black liquor in the 5-level black liquor preheater A5 enters the 4-effect evaporator, and then flows downstream to the n-effect evaporator, the black liquor in the n-effect evaporator enters the intermediate liquid pump HB2, and then countercurrently passes through the 9-1 level intermediate liquid preheaters B9-B1 in sequence, the black liquor in the 1-level intermediate liquid preheater B1 enters the 1-effect evaporator, and then flows downstream to the 3-effect evaporator, and the concentrated black liquor in the 3-effect evaporator enters the concentrated liquid storage tank Y G , Concentrate storage tank Y G Connect with the pipeline for discharging black liquor concentrate to discharge the black liquor out of the process;

[0063] The steam process technology comprises: a steam source enters a first-effect evaporator to supply heat to the first-effect evaporator, the secondary steam discharged from the first-effect evaporator supplies heat to a heater H2 and a second-stage intermediate liquid preheater B2 of a second-effect evaporator, the secondary steam discharged from the second-effect evaporator supplies heat to a heater H3 and a third-stage intermediate liquid preheater B3 of a third-effect evaporator, the secondary steam discharged from the third-effect evaporator supplies heat to a heater H4 and a fourth-stage intermediate liquid preheater B4 of a fourth-effect evaporator, the secondary steam discharged from the fourth to eighth-effect evaporators supplies heat to heaters H5 to H9, fifth to ninth-stage black liquor preheaters A5 to A9 and fifth to ninth-stage intermediate liquid preheaters B5 to B9 of fifth to ninth-effect evaporators respectively, the secondary steam discharged from the ninth-effect evaporator enters a partition condenser N to be condensed into condensed water, and the non-condensable gas in the partition condenser N is discharged by a vacuum pump ZB;

[0064] The condensed water process includes: the condensed water of the heater H1 of the first effect evaporator enters the first intermediate liquid preheater B1, the condensed water of the first intermediate liquid preheater B1, the second intermediate liquid preheater B2 and the heater H2 of the second effect evaporator enters the heater H3 of the third effect evaporator for flashing, the condensed water of the heater H3 of the third effect evaporator and the third intermediate liquid preheater B3 enters the heater H4 of the fourth effect evaporator for flashing, the condensed water of the heater H4 of the fourth effect evaporator and the fourth intermediate liquid preheater B4 enters the heater H5 of the fifth effect evaporator for flashing, the heaters H5 of the fifth to eighth effect evaporators enter the heaters H6 of the fifth to eighth effect evaporators for flashing, 5～ The condensed water from H8, 5-8 level black liquor preheaters A5-A8 and 5-8 level intermediate liquid preheaters B1-B8 enters the heaters H6-H9 of the 6-9 effect evaporators for flashing, and the condensed water from the heater H9 of the 9-effect evaporator, the 9-level black liquor preheater A9 and the 9-level intermediate liquid preheater B9 enters the condensed water tank N G Condensate tank N G The condensed water in the process is pumped to the condensed water pipe outside the process through the condensed water pump NB.

[0065] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A black liquor bellows super-efficient evaporation device, characterized in that: It includes 1 to n effect evaporators, 1 to n stage heaters, 1 to n stage intermediate liquid preheaters, 5 to n stage black liquor preheaters, condensers, vacuum pumps, black liquor feed pumps, intermediate liquid pumps, condensate tanks, condensate pumps, concentrate tanks and concentrate pumps, where n is an integer of 7 to 10; The liquid inlet of the n-stage black liquor preheater is connected to the outlet of the black liquor feed pump. With the flow direction of the black liquor as the front, in the 5-n-stage black liquor preheaters, the outlet of the n-stage black liquor preheater is connected to the inlet of the n-1-stage black liquor preheater, the outlet of the latter-stage black liquor preheater is connected to the inlet of the previous-stage black liquor preheater, the outlet of the 5-stage black liquor preheater is connected to the inlet of the 4-effect evaporator, the outlet of the 4-effect evaporator is connected to the inlet of the 5-effect evaporator, and so on. The liquid outlet is connected to the inlet of the intermediate liquid pump; the outlet of the intermediate liquid pump is connected to the liquid inlet of the n-stage intermediate liquid preheater; the liquid outlet of the n-stage intermediate liquid preheater is connected to the liquid inlet of the n-1-stage intermediate liquid preheater; the liquid outlet of the 1-stage intermediate liquid preheater is connected to the liquid inlet of the 1-effect evaporator; the liquid outlet of the 1-effect evaporator is connected to the liquid inlet of the 2-effect evaporator, the liquid outlet of the 2-effect evaporator is connected to the liquid inlet of the 3-effect evaporator, and the liquid outlet of the 3-effect evaporator is connected to the liquid inlet of the concentrated liquid storage tank; In the 1-3 effect evaporators, the secondary steam outlet of the 1 effect is connected to the low-pressure steam inlet of the steam ejector, the heater inlet of the 2 effect evaporator, and the steam inlet of the 2nd intermediate liquid preheater; the secondary steam outlets of the 2 effect evaporators and the 3 effect evaporators are respectively connected to the heater steam inlet of the 3 effect evaporator and the 4 effect evaporator and the steam inlet of the 3rd intermediate liquid preheater and the 4th intermediate liquid preheater; the secondary steam outlets of the 4-n-1 effect evaporators are respectively connected to the heater steam inlet of the 5-n effect evaporators and the steam inlet of the 5-n black liquor preheater and the 5-n intermediate liquid preheater; the secondary steam outlet of the n effect evaporator is connected to the steam inlet of the partition condenser; the non-condensable gas outlet of the partition condenser is connected to the vacuum pump; The condensed water outlet of the heater of the 1st-effect evaporator is connected to the condensed water inlet of the 1st-level intermediate liquid preheater, and the condensed water outlets of the 1st-level intermediate liquid preheater, the 2nd-level intermediate liquid preheater and the heater of the 2nd-effect evaporator are all connected to the flash condensed water inlet of the heater of the 3rd-effect evaporator; the condensed water outlet of the heater of the 3rd-effect evaporator and the 3rd-level intermediate liquid preheater are connected to the flash condensed water inlet of the heater of the 4th-effect evaporator; the condensed water outlet of the heater of the 4th-effect evaporator and the 4th-level intermediate liquid preheater are connected to the flash condensed water inlet of the heater of the 5th-effect evaporator; the condensed water outlet of the heater of the 5th-n-1st-effect evaporator, the 5th-n-1st-level black liquor preheater and the 5th-n-1st-level intermediate liquid preheater are connected to the flash condensed water inlet of the heater of the 6th-nth-effect evaporator; the condensed water outlet of the heater of the nth-effect evaporator, the nth-level black liquor preheater and the nth-level intermediate liquid preheater are connected to the inlet of the condensed water tank.

2. The black liquor corrugated tube super-efficiency evaporation device according to claim 1, characterized in that: The condenser is a corrugated tube partition condenser or a falling film condenser.

3. The black liquor corrugated tube super-efficiency evaporation device according to claim 1, characterized in that: The boiler steam is connected to the steam jet extractor through a pipeline, and the low-pressure steam inlet of the steam jet extractor is connected to the secondary steam outlet of the first-effect evaporator.

4. The black liquor corrugated tube super-efficiency evaporation device according to claim 1, characterized in that: The heater of the evaporator is a short-tube corrugated tube structure, and the black liquor preheater and the intermediate liquid preheater are long-tube corrugated tube structures.

5. A black liquor corrugated tube super-efficient evaporation process, implemented based on any one of the devices described in claims 1-4, characterized in that: Including material flow technology, steam flow technology and condensate flow technology; The material flow process comprises: black liquor enters a black liquor feed pump from outside the process, and then countercurrently passes through n to 5 levels of black liquor preheaters in sequence, the black liquor in the 5-level black liquor preheater enters a 4-effect evaporator, and then flows downstream to an n-effect evaporator, the black liquor in the n-effect evaporator enters an intermediate liquid pump, and then countercurrently passes through n to 1-level intermediate liquid preheaters in sequence, the black liquor in the 1-level intermediate liquid preheater enters a 1-effect evaporator, and then flows downstream to a 3-effect evaporator, the concentrated black liquor in the 3-effect evaporator enters a concentrated liquid storage tank, the concentrated liquid storage tank is connected to a pipeline for discharging concentrated black liquor, and the black liquor is discharged from the process; The steam process technology comprises: a steam source enters a first-effect evaporator to supply heat to the first-effect evaporator, the secondary steam discharged from the first-effect evaporator supplies heat to a heater and a second-stage intermediate liquid preheater of a second-effect evaporator, the secondary steam discharged from the second-effect evaporator supplies heat to a heater and a third-stage intermediate liquid preheater of a third-effect evaporator, the secondary steam discharged from the third-effect evaporator supplies heat to a heater and a fourth-stage intermediate liquid preheater of a fourth-effect evaporator, the secondary steam discharged from 4 to n-1-effect evaporators supplies heat to heaters, fifth to n-stage black liquor preheaters and fifth to n-stage intermediate liquid preheaters of fifth to n-effect evaporators respectively, the secondary steam discharged from the n-effect evaporator enters a partition condenser to be condensed into condensed water, and the non-condensable gas in the partition condenser is discharged by a vacuum pump; The condensed water process technology includes: condensed water from the heater of the 1st effect evaporator enters the 1st level intermediate liquid preheater, condensed water from the 1st level intermediate liquid preheater, the 2nd level intermediate liquid preheater and the heater of the 2nd effect evaporator enters the heater of the 3rd effect evaporator for flashing, the heater of the 3rd effect evaporator and the condensed water from the 3rd level intermediate liquid preheater enters the heater of the 4th effect evaporator for flashing, the heater of the 4th effect evaporator and the condensed water from the 4th level intermediate liquid preheater enters the heater of the 5th effect evaporator for flashing, the heater of 5 to n-1 effect evaporators, 5 to n-1 level black liquor preheaters and 5 to n-1 level intermediate liquid preheaters enter the heater of 6 to n effect evaporators for flashing, the heater of the n effect evaporator, the nth level black liquor preheater and the nth level intermediate liquid preheater enter the condensed water tank, and the condensed water in the condensed water tank is passed to the condensed water pipe outside the process through a condensed water pump.

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