KR100549637B1 - Condensing water recycling system for industrial plant using steam - Google Patents

Abstract

The present invention by reusing the hot condensate discharged from the distillation column distillation column reboiler and heat exchanger, heating, freezing, etc. steam trekking, it is possible to drastically reduce the cost of steam use of energy costs, according to the overall The present invention relates to a condensate utilization system of an industrial facility using steam, which can greatly reduce energy costs.

The present invention is to increase the temperature of the distillation column feed water by using the high temperature condensate generated after the use of steam in the industrial equipment including a distillation column operation equipment, reuse the first distillation column treated water in the secondary distillation column, heater or steam tracing By properly utilizing the waste heat of condensate, such as using it as a heat source, it is possible to reduce the use of steam by 10-30% of energy costs, and ultimately to save steam and contribute to the prevention of environmental pollution. Provide a condensate utilization system for the industrial equipment used.

Industrial facilities, steam, condensate, recycling, distillation towers, radiators, steam tracing

Description

Condensing water recycling system for industrial plant using steam             

1 is a system configuration diagram showing an example of a typical industrial equipment using steam

2 is a system configuration diagram showing an example of industrial equipment to which the condensate utilization system according to the present invention is applied.

3 is a system configuration diagram showing another example of the industrial equipment to which the condensate utilization system according to the present invention is applied.

Figure 4 is a system configuration showing another example of the industrial equipment applying the condensate utilization system according to the present invention

Figure 5 is a graph showing the result of reducing the steam consumption of the distillation column by increasing the temperature of the distillation column feed water in the condensate utilization system according to the present invention

Figure 6 is a graph showing the result of reducing the steam of the distillation column reboiler in the condensed water utilization system according to the present invention

<Explanation of symbols for main parts of drawing>

10: boiler 11a, 11b: distillation column

12: condensate tank 13: cooler

14: impurity remover 15: condensate recovery line

16a, 16b: valve 17a, 17b, 17c, 17d: condensate line

18: heat exchanger 19: supply water line

20: heater 21: auxiliary condensate tank

22: steam tracing 23a, 23b: discharge line

24a, 24b: supply line 25a, 25b: pump

The present invention relates to a system that can reduce energy costs by recycling condensate generated in industrial facilities using steam, in particular, the high temperature condensate discharged from the distillation column for distillation column reboiler and heat exchanger, heating, freeze protection The present invention relates to a condensate utilization system of an industrial facility using steam, which can reduce the use of steam by 10 to 30% of the energy cost by reusing steam trestle and the like, thus greatly reducing the overall energy cost of the industrial facility. .

In general, the key to the competitiveness of industrial facilities is energy cost reduction, which affects the competitiveness of products.

The current trend is to concentrate the core competencies of companies on technology development and investment to reduce energy costs, but it is insufficient to systemize the developed technology and apply it to industrial facilities, especially the equipment industry as a whole.

In addition, although it is recognized that energy cost has a great influence on manufacturing cost, the device industry has characteristics such as risk, product purity, and continuous operation, which makes it difficult to apply, and there are few successful application cases. It is not spreading throughout the industry.

Accordingly, the present invention has been made in view of such a point, by using a high temperature condensate generated after the use of steam in an industrial facility including a distillation column operation equipment to increase the temperature of the distillation column feed water, or the first distillation column treated water By utilizing the waste heat of condensate properly, such as reusing it in a second distillation column or as a heat source for a heater or steam tresing, the cost of steam can be reduced by 10-30% of the energy cost, and ultimately the energy resource saving. The aim is to provide a system for utilizing condensate in industrial installations that use steam to contribute to the prevention of environmental and environmental pollution.

The present invention for achieving the above object is a distillation tower operating by receiving steam from the boiler, a condensate tank for storing the condensate discharged after being used as a heat source in the distillation column, and the condensate discharged from the condensate tank cooler and impurities In an industrial facility using steam including a condensate recovery line to be sent back to the boiler after the eliminator, a valve is installed on one side of the condensate recovery line, branching / extending one condensate line on the front end of the valve The discharge side exiting the heat exchanger at the same time as connecting to the heat exchanger side is connected to the rear end side of the valve to be sent to the cooler, and the supply water line connected to the distillation column is connected to the heat exchanger side after being connected to the temperature of the feed water supplied to the distillation column. It is characterized in that to increase.

In addition, at one side of the condensate recovery line, the other condensate line is branched / extended and connected to the supply side of the heater to use the condensate as a heat source of the heater, and the outlet side of the heater is connected to the condensate recovery line via the auxiliary condensate tank. Condensate exiting the heater is characterized in that it is sent to the cooler.

In addition, at one side of the condensate recovery line, the other condensate line is branched / extended and connected to the supply side of the steam trestle to use the condensate as a heat source for the heater, and the discharge side of the steam trestle is connected to the condensate return line via the auxiliary condensate tank. The condensed water exiting the steam tressing is characterized in that it is sent to the cooler.

In addition, a valve is installed on the discharge line of the distillation column, and branching / extending the other condensate line at the front side of the valve and connecting to the supply line of the distillation column so that condensed water can be used as a heat source of the distillation column. do.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, an example of industrial equipment to which the condensate utilization system of the present invention is applied is as follows.

As shown in FIG. 1, the steam provided in the boiler 10 is supplied through supply lines 24a and 24b and used as a heat source of the distillation towers 11a and 11b and then the discharge line 23a, It is sent to the condensate tank 12 through the 23b, the upper low pressure steam in the condensate tank 12 is discharged to the atmosphere while the lower condensate proceeds through the condensate recovery line 15 while the cooler 13 for the temperature down After passing through the impurity remover 14 for removing impurities, it is sent back to the boiler 10.

On the other hand, the steam provided by the boiler 10 is discharged to the atmosphere after being used as a heat source of the steam tracing 22 or the heater 20 for heating to prevent freezing.

Here, reference numeral 19 denotes a feed water line for supplying the feed water used in the distillation column, and 25a indicates a pump for forcing the condensate.

In such a system, losses in the first cooler, heat and condensate losses in the second steam trestle and heater, and third steam losses due to the low distillation column feed water temperature are used.

The condensate utilization system provided by the present invention can reduce the steam consumption of the distillation column by increasing the temperature of the distillation tower feed water by utilizing the waste heat of the condensate sent to the boiler firstly, and secondly stops the steam tracing and steam use of the heater. The cost of steam can be reduced by replacing condensate with the use of condensate, and the steam consumption of the distillation column can be reduced by repeating reuse of the condensate from the steam once again.

This will be described in more detail as follows.

As shown in Figure 2, here shows a condensate utilization system that can reduce the steam consumption of the distillation column by increasing the temperature of the distillation column feed water utilizing the waste heat of the condensate sent to the boiler.

That is, a valve 16a is installed between one side of the condensate return line 15, for example, the pump 25a and the cooler 13, and one condensate line 17a is disposed at the front end side of the valve 16a. Branched and extended to be connected to the heat exchanger 18 side installed on one side of the distillation column (11a), and the discharge side exiting the heat exchanger (18) is connected to the rear end side of the valve (16a) to complete the heat exchange action Is sent back to the boiler 10 via the cooler 13 and the impurity remover 14.

The condensate flow as described above proceeds under the condition that the condensate return line 15 is blocked by the operation of the valve 16a.

Normally, the heat exchanger at this time can operate a commercially available heat exchanger under specific conditions for the above system.

In addition, since the supply water line 19 connected to the distillation column 11a is connected after passing through the heat exchanger 18 side, the high temperature supply water that has completed heat exchange with the condensed water in the heat exchanger 18 is supplied to the distillation tower 11a. It becomes possible.

Usually the temperature of the condensate discharged from the distillation column (11a), (11b) is about 130 ~ 150 ℃, the temperature of the condensate recovered after passing through the condensate tank 12 is about 120 ~ 140 ℃ is supplied to the distillation tower (11a) The temperature of the feed water can be sufficiently increased.

Thus, by using the condensate of 120 ~ 140 ℃ sent to the boiler to increase the temperature of the feed water it is possible to reduce the steam consumption of the distillation column.

For example, even if the temperature of the feed water is increased by only 50% through heat exchange with condensate, the amount of steam used in the distillation column can be reduced by about 25%.

Of course, these results do not apply to all distillation towers in a constant manner, and the supply water temperature before the heat exchanger installation, the condensate temperature, the distillation column operating pressure / temperature, the distillation column feed water supply location and the purity of the distillation column products, the heat exchange capacity of the heat exchanger, Depending on the items such as the amount of condensate and the composition / boiling point of the material, the result is somewhat different, and the system should be changed slightly depending on the situation, but it is accompanied by changing the feed water supply position of the distillation column according to the temperature rise. Increasing the temperature of the feed water can reduce the use of distillation column steam by more than 50% of its rise.

Such a result of reducing the amount of steam is well shown in FIG.

As shown in FIG. 3, here is shown a system that utilizes condensate as a heat source for steam tracing and heaters.

That is, one condensate line (17b) is branched on one side of the condensate recovery line 15 is extended and connected to the supply side of the heater 20, or another condensate line (17c) is extended after branching and steam It is connected to the supply side of the tracing 22.

Therefore, the condensed water provided from the condensate tank 12 side can be used as a heat source of the heater 20 or as a heat source of the steam tracing 22.

In addition, each discharge side of the heater 20 or steam tracing 22 is connected to the auxiliary condensate tank 21, the condensed water exiting the heater 20 and the steam tresing 22 is not discharged to the atmosphere, but the pump 25b ) Is sent to the condensate recovery line 15 and then sent back to the boiler 10 via the cooler 13 and the impurity remover 14.

By eliminating steam and replacing condensate with the use of heaters or steam-tresting, the cost of steam can be zeroed.

For example, in the case of industrial facilities including distillation towers, steam and copper pipes are used to prevent freezing and freezing of pipes and various equipment during the winter, but the temperature is prevented from falling. In addition, the used steam is still flowing to the atmosphere, which required energy saving.

In order to replace steam with condensate instead of steam, it is necessary to adjust the proper length of steam tracing, adjust the distribution position of supply pipe and steam tracing, complement steam tracing trap, complement condensate return pipe, and balance the condensate supply pressure and recovery pressure. It is desirable to make system-wide adjustments, such as maintaining the proper condensate supply pressure and maintaining the atmospheric pressure of the auxiliary condensate tank after use.

In addition, the cost of heating in winter also takes up a considerable portion of industrial facilities including distillation towers. Especially, steam is used in each process and steam is also used in heating and restaurants. Energy savings were needed in this area.

Therefore, it is possible to zero the cost of using the steam of the heater by using it once in the distillation tower process and using the spare temperature of the condensate sent to the boiler as a heat source of the heater.

In order to replace condensate in place of steam in the heater, for example, heating radiator, heating heat exchanger, hot water heater, water heater, dishwasher, air conditioner, bathroom heat exchanger, maintain proper condensate supply pressure, atmospheric pressure of auxiliary condensate tank after use It is desirable to make system-wide adjustments, such as maintenance.

As shown in Figure 4, here shows a condensate utilization system to reduce the steam of the distillation column reboiler by repeating reuse of the condensed water of the once used steam back to the distillation column reboiler.

To this end, a valve 16b is installed in the discharge line 23a of the distillation column 11a, and at the front end side of the valve 16b, one condensate line 17d branches and extends to supply the distillation column 11b. Connected to line 24b.

Accordingly, the condensed water discharged from one distillation column 11a can be used as a heat source, that is, a reboiler of the other distillation column 11b.

At this time, the flow of the condensate can proceed to the distillation column 11b side according to the operation of the valve 16b.

Previously, when condensate once used in one distillation column (11a) was sent to the boiler (10), the condensate temperature was lowered to about 100 ° C. in the cooler (13) to remove iron and foreign substances, where energy loss occurred.

The condensate reboiler system is to use the condensate from the distillation column once again in the second distillation column and to use it again in distillation column 3, 4 distillation column to reduce the condensate temperature to 100 ℃ or less to finally send to the boiler The use of steam can be reduced by the use of such condensed water repeatedly.

Such a result of reducing the amount of steam is well shown in FIG.

As described above, the present invention increases the temperature of the distillation column feed water using high-temperature condensate generated after using steam in an industrial facility, reuses the first distillation column treated water in the secondary distillation column, or heat source of a heater or steam trestle. By providing a condensate utilization system that can properly utilize the waste heat of condensate, such as the use of water, it can reduce steam use costs by 10-30% among energy costs, thereby securing product competitiveness and globally. Given the reality of finite energy resources, not only resource saving but also environmental pollution can be reduced as much as the reduction of resource utilization.

Claims (4)

A distillation tower (11a), (11b) operating by receiving steam from the boiler (10), a condensate tank (12) for storing the condensate discharged after being used as a heat source in the distillation tower (11a), (11b), and In an industrial facility using steam including a condensate recovery line 15 for returning the condensate discharged from the condensate tank 12 to the boiler 10 via the cooler 13 and the impurity remover 14, A valve 16a is installed at one side of the condensate return line 15, and a condensate line 17a is branched / extended at the front end side of the valve 16a to be connected to the heat exchanger 18, and at the same time, a heat exchanger is provided. The discharge side exiting (18) is connected to the rear end side of the valve (16a) to be sent to the cooler 13, the supply water line (19) connected to the distillation column (11a) is passed through the heat exchanger (18) side Condensed water utilization system of the industrial equipment using the steam, characterized in that to be connected to increase the temperature of the feed water supplied to the distillation column (11a). The condensate is used as a heat source of the heater 20 by branching / extending the other condensate line 17b on one side of the condensate return line 15 and connecting to the supply side of the heater 20. The discharge side of the heater 20 is connected to the condensate recovery line 15 via the auxiliary condensate tank 21, the condensed water exiting the heater 20 is sent to the cooler 13, the industry using steam, characterized in that Condensate utilization system of equipment. The condensate is used as a heat source as a heat source for a heater by connecting to the supply side of the steam tracing 22 while simultaneously branching / extending the other condensate line 17c on one side of the condensate return line 15. The discharge side of the tresing 22 is connected to the condensate return line 15 via the auxiliary condensate tank 21, the condensate exiting the steam tresing 22 is sent to the cooler (13) Condensate utilization system of industrial facilities. The method of claim 1, wherein the valve 16b is installed in the discharge line 23a of the distillation column 11a, and the other condensate line 17d is branched / extended at the front end side of the valve 16b and the distillation column ( The condensate utilization system of the industrial equipment using steam, characterized in that the condensed water to be used as a heat source of the distillation column (11b) by connecting to the supply line (24b) of 11b).

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