KR102127960B1 - System and Method for Liquid Air Evaporation with Industrial Plant - Google Patents

Abstract

The present invention connects a liquefied air regasification system to an industrial plant, recovers heat sources step by step from an industrial plant to produce power, and uses the produced power in an industrial plant to liquefy it in connection with an industrial plant that can improve energy efficiency. It relates to an air regasification system and method.
A liquefied air regasification system in connection with an industrial plant according to the present invention includes a turbine-generator for generating electric power using regasification air; A liquid air regasification device including the turbine-generator and revaporizing liquid air to produce electric power; A preheating tower for heating the raw materials; A cooler that cools the product produced by the heating using cold heat of compressed air at a low temperature discharged from the turbine-generator; A product production plant including the preheating tower and a cooler, and producing a product including a heating and cooling process of a raw material; And a working fluid turbine-generator for generating electric power using a working fluid, the Rankine cycle for generating additional power, wherein the Rankine cycle comprises: preheating the working fluid to be supplied to the working fluid turbine-generator. It characterized in that it further comprises a; working fluid heater to vaporize by using the waste heat of the exhaust gas discharged from the tower.

Description

{System and Method for Liquid Air Evaporation with Industrial Plant}

The present invention connects a liquefied air regasification system to an industrial plant, and recovers heat sources step by step from an industrial plant to produce power, and the generated power is used in an industrial plant to liquefy it in connection with an industrial plant that can improve energy efficiency. It relates to an air regasification system and method.

Industrial plants are unit plants that can produce various industrial products such as power, oil, and cement in various industries. In an industrial plant, a heating process is accompanied, so that almost all of the waste heat is generated. In the past, waste heat produced by industrial plants was released into the atmosphere, but in recent years, efforts have been made to increase energy efficiency and prevent environmental pollution by recovering and using this waste heat.

Among various industrial plants, for example, a cement production plant that produces cement is a process of producing a clinker, an intermediate product by firing a mixed raw material containing limestone as a main raw material, and a cement, which is a final product, by mixing additives such as plaster on the clinker. It includes the production process.

In the clinker production process of the cement production plant, waste heat in a wide temperature range is generated, and about 20% to 30% of the waste heat is released into the atmosphere.

Several methods have been proposed to improve plant energy efficiency by recovering waste heat from the exhaust gas generated in the clinker production process. Most of the methods for recovering the heat source of the existing cement production plant generate electricity by directly using the exhaust heat source from the kiln. Therefore, the existing methods require additional facilities such as a cooling facility to recover a high temperature heat source from the kiln.

In addition, the waste heat of industrial plants is difficult to apply to simple steam power generation due to the wide supply temperature range of the heat source according to the load fluctuation, and the efficiency is low.

Moreover, due to the nature of domestic cement production plants, the utilization rate is approximately 70% to 30%, and is not continuously operated.

That is, it is necessary to develop a method for efficiently utilizing the waste heat in consideration of the characteristics of a cement production plant in which a wide range of temperature is generated and the utilization rate is not constant.

Therefore, the present invention is to solve such a problem, and by linking a liquid air regasification apparatus to an industrial plant such as a cement production plant, it is possible to recover a heat source from an industrial plant without additional equipment and effectively recover a wide range of heat sources from the industrial plant. It aims to provide a system and method for recovering liquefied air in connection with industrial plants that can be recovered.

According to an aspect of the present invention for achieving the above object, a turbine-generator for generating power using regasification air; A liquid air regasification device including the turbine-generator and revaporizing liquid air to produce electric power; A preheating tower for heating the raw materials; A cooler that cools the product produced by the heating using cold heat of compressed air at a low temperature discharged from the turbine-generator; A product production plant including the preheating tower and a cooler, and producing a product including a heating and cooling process of a raw material; And a working fluid turbine-generator for generating electric power using a working fluid, the Rankine cycle for generating additional power, wherein the Rankine cycle comprises: preheating the working fluid to be supplied to the working fluid turbine-generator. Provided is a liquefied air regasification system in connection with an industrial plant, further comprising: a working fluid heater that vaporizes using waste heat of exhaust gas discharged from the tower.

Preferably, an exhaust line connecting the preheating tower and the working fluid heater, and transferring exhaust gas from the preheating tower to the working fluid heater; And an air line connecting the turbine-generator and the cooler and transferring compressed air from the turbine-generator to the cooler.

Preferably, while the vaporized working fluid in the working fluid heater while the waste heat is recovered, the preheating tower exhaust gas is discharged from the working fluid heater may further include;

Preferably, the Rankine cycle comprises: a condenser condensing the working fluid discharged from the working fluid turbine-generator; And a working fluid pump for compressing the working fluid condensed in the condenser and circulating the working fluid heater.

Preferably, the Rankine cycle is a second working fluid that further heats a working fluid vaporized in the working fluid heater and supplied to the working fluid turbine-generator using compressed air that cools and discharges the product from the cooler. Heater; And a first air discharge line connecting the cooler and the second working fluid heater, and transferring compressed air discharged from the cooler to the second working fluid heater.

Preferably, the liquid air regasifier comprises: a heater that heats compressed air supplied to the turbine-generator; And a working fluid recovery line connected from the intermediate end of the working fluid turbine-generator to the heater, further including the working fluid discharged from the intermediate end of the working fluid turbine-generator to heat compressed air in the heater. It can be supplied as a heat source.

Preferably, the working fluid recovery line is further connected to the condenser from the heater, and the working fluid discharged after heating compressed air in the heater can be recovered to the condenser.

Preferably, the Rankine cycle may be a steam Rankine cycle using steam as a working fluid.

Preferably, the liquid air regasification apparatus further includes a heater for heating compressed air supplied to the turbine-generator, connecting the cooler with the heater, and hot compressed air discharged from the cooler, It may further include; a second air discharge line for supplying as a heat source for heating the compressed air supplied to the turbine-generator.

Preferably, a cooler exhaust line for condensing compressed air discharged from the cooler into a preheating tower exhaust gas flow transferred to the working fluid heater through the exhaust line.

Preferably, the Rankine cycle may be an organic Rankine cycle in which the working fluid is an organic compound.

Preferably, the temperature of the compressed air discharged from the cooler may be lower than the temperature of the exhaust gas discharged from the preheating tower.

Preferably, the liquid air regasifier and the power produced in the Rankine cycle can be used in the product production plant.

According to another aspect of the present invention for achieving the above object, a liquid air regasification process for generating electric power by revaporizing liquid air to drive a turbine; A product production process for producing products by heating and cooling raw materials; And a Rankine cycle process for generating power by vaporizing the circulating working fluid to drive a turbine, wherein waste heat of exhaust gas discharged from the heating process of the product production process is a heat source for vaporizing the working fluid in the Rankine cycle. It is provided, and the waste heat of the compressed air discharged from the liquid air regasification process is supplied as a cooling heat of the cooling process of the product production process.

Preferably, the waste heat discharged from the cooling process of the product production process may be supplied directly or indirectly as a heat source for regasifying the liquid air in the liquid air regasification process.

Preferably, the waste heat discharged from the cooling process of the product production process may be supplied as a heat source for heating the working fluid supplied to the turbine of the Rankine cycle.

Preferably, a portion of the working fluid discharged from the intermediate stage of the turbine of the Rankine cycle may be additionally supplied to a heat source for heating the regasification air supplied to the turbine of the liquid air regasification process.

Preferably, while the regasification air is heated, the working fluid whose temperature is lowered is condensed, and the condensed working fluid is vaporized to be recycled to the turbine of the Rankine cycle.

Preferably, some of the waste heat discharged from the cooling process of the product production process may be supplied as a heat source for vaporizing the working fluid in the Rankine cycle.

Preferably, the electric power produced in the liquid air regasification process and the Rankine cycle process can be used in the product production process.

The liquefied air regasification system and method associated with the industrial plant according to the present invention can produce additional power while liquefying clean air introduced from the atmosphere to obtain liquefied air and regasifying liquefied air with high energy density. Therefore, it is possible to provide an environmentally friendly facility that does not generate air pollutants.

In addition, by utilizing compressed air after regasifying the liquefied air to recover waste heat from the plant, it is not necessary to provide additional facilities for heat source recovery, thereby reducing installation and operation costs of additional facilities.

In addition, since the power is generated from the waste heat of the plant using the Rankine cycle, it is easier to apply and improve the power production efficiency compared to the prior art.

In addition, by gradually recovering the waste heat in various temperature ranges generated from the plant, it is possible to shorten the initial uptime leading to power generation.

In addition, it is possible to effectively utilize waste heat to minimize waste heat released into the atmosphere.

In addition, it is possible to reduce the production cost of plant products by generating power using waste heat generated during plant operation and using the generated power for plant operation.

1 is a schematic view showing a liquefied air regasification system in connection with an industrial plant according to a first embodiment of the present invention.
2 is a schematic view showing a liquefied air regasification system in connection with an industrial plant according to a second embodiment of the present invention.

In order to fully understand the operational advantages of the present invention and the objects achieved by the practice of the present invention, reference should be made to the accompanying drawings and the contents described in the accompanying drawings, which illustrate preferred embodiments of the present invention.

Hereinafter, the configuration and operation of the preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Here, when adding reference numerals to the components of each drawing, it should be noted that the same components are denoted by the same reference numerals as much as possible even though they are displayed on different drawings. In addition, the following examples may be modified in various other forms, and the scope of the present invention is not limited to the following examples.

Hereinafter, a liquefied air regasification system and method in connection with an industrial plant according to embodiments of the present invention will be described with reference to FIGS. 1 and 2.

In one embodiment of the present invention to be described later, the industrial plant will be described as an example that it is a cement production plant.

First, with reference to FIG. 1, a liquefied air regasification system and method in connection with an industrial plant according to a first embodiment of the present invention will be described.

Liquefied air regasification system in connection with an industrial plant according to a first embodiment of the present invention, a liquid air storage device; Cement production plant 200; And Rankine cycle 300.

The liquid air storage device of this embodiment includes: an air liquefaction device (not shown) that liquefies air and stores it in a liquid state; And a liquid air regasification apparatus 100 for regasifying liquid air and generating electric power using the regasified gas air.

Although not shown in the drawing, the air liquefaction apparatus includes: an air compressor (not shown) for compressing air introduced from the outside; A main heat exchanger (not shown) that cools (liquefies) the compressed air by heat exchange; A pressure reducing valve (not shown) for depressurizing the liquefied air in the main heat exchanger; And a liquid air storage tank 101 for storing liquefied air.

The air compressor may be configured as a multi-stage compressor including a plurality of compression units to compress air supplied at room temperature and pressure to a target pressure, for example, about 100 bar or more over multiple stages. In the present embodiment, the air compressor may be a three-stage compressor that compresses gaseous air over three stages, including three compression units.

In addition, an intercooler (not shown) for intermediately cooling the gas air whose temperature has increased during the compression process may be installed at the rear end of each compressor.

Compressed air compressed in the air compressor is introduced into the main heat exchanger and liquefied by heat exchange, for example, compressed air is cooled to about -184°C by heat exchange, and at least a portion of the liquid can be liquid.

The pressure reducing valve may reduce compressed air liquefied at least partially in the main heat exchanger to the storage pressure of the liquid air storage tank 101. In this embodiment, the pressure reducing valve may be an expansion means such as an expansion valve or a Joule-Thomson valve or an expander, and at least a portion of the liquefied compressed air is thermally expanded, so that the temperature of the air can be lowered by the Joule-Thomson effect . Therefore, it is possible to increase the liquefaction yield and storage properties of air. For example, in the main heat exchanger, compressed air whose temperature is lowered to about -184°C may be lowered to -190°C or less while passing through the pressure reducing valve.

The liquid air storage tank 101 stores the liquefied liquid air while passing through the air liquefaction apparatus, and insulates the liquid air to be stored in a liquid state while maintaining an extremely low temperature (for example, about -190°C or less). It may have been done.

For example, the liquid air storage tank 101 may be operated to store liquid air under conditions of about 1 bar to 1.5 bar and about -190°C to -185°C.

In this embodiment, the liquid air regasification apparatus 100 includes a cryogenic pump 102 that pressurizes the liquid air stored in the liquid air storage tank 101; A regasifier 103 that heats (vaporizes) the pressurized liquid air by heat exchange; A heat exchanger 104 that heats the air vaporized in the regasifier 103 by heat exchange; And turbine-generators 106 and 108 for driving the turbine using vaporized gas air and converting the driving force of the turbine into electric power to produce electric power.

In addition, in this embodiment, the liquid air storage tank 101, the cryogenic pump 102, the regasifier 103, the heat exchanger 104, and the turbine-generators 106 and 108 constituting the liquid air regasification apparatus 100. ) Can be connected by the air line (AL), and the liquid air from the liquid air storage tank (101) flows and regasses along the air line (AL), drives the turbine and utilizes it as a working fluid to produce power do.

As described above, according to the present embodiment, clean air from the atmosphere is liquefied and stored through a compression and expansion process, and electricity can be produced while re-evaporating the liquefied air as necessary.

The power generation efficiency of the turbine-generators 106 and 108 can be improved by increasing the turbine inlet pressure to maximize the differential pressure with the turbine outlet pressure. That is, according to the present embodiment, the cryogenic pump 102 increases the pressure of the liquid air introduced into the turbine to increase the turbine inlet pressure, thereby maximizing the inlet and outlet differential pressures of the turbine-generators 106 and 108 to generate power. Can increase

The cryogenic pump 102 of this embodiment can pressurize the liquid air stored in the liquid air storage tank 101 at a pressure of about 1.5 bar at a pressure of about 22 bar, and the turbine-generator at a pressure of about 22 bar. The regasification air introduced at 106 and 108 can be expanded while driving the turbine.

As described above, by pressurizing the liquid air to be regasified by the cryogenic pump 102, it is possible to expect an effect that the turbine inlet and outlet differential pressure increases, and thus the amount of power generation increases. In addition, compressed air discharged after driving the turbine-generators 106 and 108 is supplied to the cement production plant 200 as described below, and can be utilized as a means for recovering waste heat of the cement production plant 200. .

In the regasifier 103 and the heat exchanger 104 of this embodiment, cold heat of the liquid air is recovered by heat exchange between the liquid air flowing along the air line AL and the refrigerant flowing along the refrigerant line ML. , All of the liquid air from which cold heat has been recovered can be vaporized.

Although not shown in the drawing, the refrigerant line ML may form a cycle connected to a main heat exchanger for liquefying compressed air in the above-described air liquefaction apparatus. That is, the refrigerant flowing along the refrigerant line ML can cool the compressed air in the main heat exchanger of the air liquefaction apparatus with cold heat recovered from the liquid air in the regasifier 103 and the heat exchanger 104. However, it is not limited thereto.

The turbine-generators 106 and 108 of this embodiment include: a primary turbine-generator 106; And a secondary turbine-generator 108; may be a two-stage turbine-generator 106, 108.

That is, the regasification air vaporized while passing through the regasifier 103 and the heat exchanger 104 is first supplied as a working fluid of the first turbine-generator 106 and then discharged after generating power, and the second turbine- It can be supplied as a working fluid of the generator 108 and then discharged after producing electricity.

According to this embodiment, the primary heater 105 is installed at the front end of the primary turbine-generator 106 and further heats the regasification air supplied to the primary turbine-generator 106; A secondary heater 107 installed at a front end of the secondary turbine-generator 108 and further heating regasification air discharged from the primary turbine-generator 106 and supplied to the secondary turbine-generator 108; It further includes.

In this embodiment, two turbine-generators 106 and 108 are described as an example in which they are connected in series (series), but the number of turbine-generators 106 and 108 is not limited thereto, and one or more may be provided. have. However, one or more heaters 105 and 107 are provided at the front end of the turbine-generators 106 and 108, respectively, and the regasification air supplied to the turbine-generators 106 and 108 is heaters 105 and 107. It can be fed after being heated in. In addition, two or more turbine-generators 106 and 108 may be installed in parallel to generate power. In addition, the primary turbine-generator 106 and the secondary turbine-generator 108 may be operated at the same time, either one may be operated, or may be operated with a time difference.

According to this embodiment, in order to improve the power generation efficiency of the power generation turbine, as described above, along with a method of maximizing the differential pressure between the inlet pressure and the outlet pressure of the turbine, the temperature of the fluid introduced into the turbine is increased. . That is, according to the present embodiment, the primary heater 105 and the secondary heater 107 are provided to further heat the regasification air introduced into the turbine-generators 106 and 108, thereby increasing the turbine inlet temperature to increase the turbine -It is possible to improve the power generation efficiency of the generators (106, 108).

The primary heater for heating compressed air supplied to the primary turbine-generator 106 is a heating medium for heating compressed air from the primary heater 105 and a secondary heater for heating compressed air supplied to the secondary turbine-generator 108 ( In 107), as the heat medium for heating the compressed air, waste heat from the Rankine cycle 300 described later can be utilized.

The cement production plant 200 includes a preheating tower 201 that preheats the mixed raw materials such as limestone and iron oxide before mixing and firing the mixed raw materials; A kiln (klin) 202 for producing a clinker, an intermediate product of cement, by heating the mixed raw material preheated in the preheating tower 201; And a clinker cooler 203 that cools the clinker.

In the preheating tower 201, the mixed raw material to be supplied to the kiln 202 is preheated by receiving the mixed raw material through the raw material input unit. In the kiln 202, the mixed raw material is heated to about 1,300°C to 1,500°C to produce an intermediate product by plasticity. Before supplying the mixed raw material to the kiln 202, about 400 in the preheating tower 201 By heating up to about 900°C or around 900°C, thermal efficiency and productivity can be increased.

The mixed raw material preheated in the preheating tower 201 is introduced into the kiln 202, and the preheated mixed raw material is heated in the kiln 202 to produce clinker as an intermediate product. In the kiln 202, the mixed raw material may be heated by burning fuel.

The clinker produced in the kiln 202 is introduced into the clinker cooler 203, and the clinker cooler 203 cools the hot clinker, and the cooled clinker is stored or supplied to a subsequent process.

The cold heat medium for cooling the high temperature clinker in the clinker cooler 203 of the present embodiment may be compressed air transferred from the liquid air regasification apparatus 100.

According to this embodiment, as shown in FIG. 1, the air line AL is connected from the rear end of the secondary turbine-generator 108 to the cold heat medium inlet of the clinker cooler 203, and the secondary turbine-generator ( Compressed air discharged after driving 108) is supplied to the clinker cooler 203 to supply cold heat to cool the clinker.

In addition, according to this embodiment, after cooling the clinker from the clinker cooler 203, the compressed air discharged by increasing the temperature may be utilized as a heating medium for heating the working fluid in the Rankine cycle 300 described later.

The Rankine cycle 300 of the present embodiment includes a steam turbine-generator 301 for driving a turbine using a gaseous working fluid and converting the driving force of the turbine into electric power to produce electric power; A condenser 302 for condensing the working fluid discharged after driving the steam turbine-generator 301; A steam pump 303 that pressurizes the working fluid to be circulated from the condenser 302 to the steam turbine-generator 301; A first steam heater 304 for heating or vaporizing the working fluid transferred from the steam pump 303 to the steam turbine-generator 301; And a second steam heater 305 for vaporizing the working fluid transferred from the first steam heater 304 to the steam turbine-generator 301 or further heating the working fluid in a gaseous state.

The working fluid of the Rankine cycle 300 of this embodiment may be steam. Steam, which is the working fluid of the Rankine cycle 300, is a steam line connecting the steam turbine-generator 301, the condenser 302, the steam pump 303, the first steam heater 304 and the second steam heater 305. Electricity may be produced while circulating the Rankine cycle 300 through a change in adiabatic and isostatic pressure along the (VL).

The condenser 302 of this embodiment may be connected to a cooling tower 307 that supplies cold heat for condensing gaseous vapor. That is, in the condenser 302, the vapor in the gaseous state is condensed by cooling water or the like circulated from the cooling tower 307, and the cooling water whose temperature is increased while condensing the steam is supplied to the cooling tower 307 again, so that the temperature can be circulated. .

The steam vaporized and heated by the first steam heater 304 and the second steam heater 305 generates power while driving the turbine of the steam turbine-generator 301.

In addition, according to this embodiment, the steam recovery line connected to the primary heater 105 and/or the secondary heater 107 of the liquefied air regasification apparatus 100 from the intermediate stage of the steam turbine-generator 301 ( VL1);.

Steam extraction from the steam turbine-generator 301 is supplied to the primary heater 105 and/or the secondary heater 107 along the vapor recovery line VL1.

The steam supplied to the primary heater 105 along the steam recovery line VL1 is used as a heat medium for heating compressed air supplied from the primary heater 105 to the primary turbine-generator 106.

The additional air supplied to the secondary heater 107 along the steam recovery line VL1 is used as a heating medium for heating compressed air supplied from the secondary heater 107 to the secondary turbine-generator 108.

While the compressed air is heated in the primary heater 105 and the temperature is lowered and discharged, the steamer is discharged from the rear end of the primary heater 105 along the steam recovery line VL1 connected to the condenser 302 of the Rankine cycle 300. It can be recycled to 302.

While the compressed air is heated in the secondary heater 107, the temperature is lowered and the exhaust is discharged from the rear end of the secondary heater 107 along the steam recovery line VL1 connected to the condenser 302 of the Rankine cycle 300. It can be recycled to 302.

Further, according to the present embodiment, the heat medium for vaporizing or heating steam in the first steam heater 304 and the second steam heater 305 of the Rankine cycle 300 utilizes waste heat discharged from the cement production plant 200. Can.

The waste heat of various temperatures is discharged from the cement production plant 200. According to the present embodiment, the waste heat of various temperatures discharged from the cement production plant 200 can be recovered step by step using the Rankine cycle 300 to effectively utilize it. have.

Exhaust gas waste heat discharged from the preheating tower 201 of the cement production plant 200 of the present embodiment is used to supply steam supplied from the first steam heater 304 of the Rankine cycle 300 to the steam turbine-generator 301 1 It is used as a heat medium to heat tea.

In addition, the waste heat discharged from the clinker cooler 203 of the cement production plant 200 of the present embodiment, the steam supplied to the steam turbine-generator 301 from the second steam heater 305 of the Rankine cycle 300 is 2 It is used as a heat medium to heat tea.

In the first steam heater 304, all of the steam may be vaporized or only a part of it may be vaporized. The vapor that is not vaporized in the first vapor heater 304 may be vaporized entirely in the second vapor heater 305.

That is, the first steam heater 304 requires a relatively low heat source, and the second steam heater 305 requires a relatively high heat source.

For example, in the preheating tower 301 of the cement production plant 200, exhaust gas at about 400° C. is discharged while preheating the mixed raw materials.

In addition, in the clinker cooler 203 of the cement production plant 200 of this embodiment, the compressed air supplied from the secondary turbine-generator 108 cools the clinker while the temperature rises, for example, to a temperature of up to about 800°C. Increases and is discharged.

In this way, in the cement production plant 200, waste heat at different temperatures is generated in each facility.

According to the present embodiment, the exhaust gas from the preheating tower 301, which is a relatively low temperature of waste heat, is utilized as a heat medium for primary heating of steam in the first steam heater 304, and clinker, which is a waste heat of relatively high temperature. The compressed air from the cooler 203 is used as a heat medium for secondary heating of the steam in the second steam heater 305.

According to this embodiment, the exhaust line (EL) connected to the high-temperature heat medium inlet of the first steam heater 304 from the exhaust port of the preheating tower 301; And a manned blower 306 for discharging the exhaust gas that has undergone heat exchange from the first steam heater 304 to the outside.

In addition, a first air discharge line AL1 connected to the high temperature heat medium inlet of the second steam heater 305 from the exhaust port of the clinker cooler 203 may be further included. The compressed air whose temperature is lowered while heating the steam from the second steam heater 305 may be discharged into the atmosphere.

Next, with reference to FIG. 2, a liquefied air regasification system and method in connection with an industrial plant according to a second embodiment of the present invention will be described. The liquefied air regasification system and method associated with the industrial plant according to the present embodiment is a modification of the first embodiment described above, such as the Rankine cycle 400, the second air discharge line AL2, and the cooler discharge line EL1, etc. Differences from the first embodiment will be mainly described. The description of the same components and their operation will be omitted, and the interactions and operations between the remaining components and them occur within the same scope. Therefore, even if a detailed description is omitted, the description and operation principle of the components indicated by the same reference numerals can be applied in the same manner as in the first embodiment.

A liquefied air regasification system in connection with an industrial plant according to a second embodiment of the present invention includes a liquid air storage device; Cement production plant 200; And Rankine cycle 400.

The liquid air storage device of this embodiment includes: an air liquefaction device (not shown) that liquefies air and stores it in a liquid state; And a liquid air regasification apparatus 100 for regasifying liquid air and generating electric power using the regasified gas air. The air liquefaction apparatus of this embodiment can be applied in the same manner as the first embodiment described above.

The liquid air regasification apparatus 100 of this embodiment includes a cryogenic pump 102 that pressurizes the liquid air stored in the liquid air storage tank 101; A regasifier 103 that heats (vaporizes) the pressurized liquid air by heat exchange; A heat exchanger 104 that heats the air vaporized in the regasifier 103 by heat exchange; And turbine-generators 106 and 108 for driving the turbine using vaporized gas air and converting the driving force of the turbine into electric power to produce electric power.

The liquid air storage tank 101, the cryogenic pump 102, the regasifier 103, the heat exchanger 104, and the turbine-generators 106 and 108 of this embodiment can be applied in the same manner as the first embodiment described above. have.

In addition, according to the present embodiment, in order to improve the power generation efficiency of the power generation turbine, as described above, along with a method of maximizing the differential pressure between the inlet pressure and the outlet pressure of the turbine, the temperature of the fluid introduced into the turbine is increased. To do. That is, according to the present embodiment, the primary heater 105 and the secondary heater 107 are provided to further heat the regasification air introduced into the turbine-generators 106 and 108, thereby increasing the turbine inlet temperature to increase the turbine -It is possible to improve the power generation efficiency of the generators (106, 108).

The primary heater for heating compressed air supplied to the primary turbine-generator 106 is a heating medium for heating compressed air from the primary heater 105 and a secondary heater for heating compressed air supplied to the secondary turbine-generator 108 ( Unlike the first embodiment that utilizes waste heat from the Rankine cycle 300 as a heating medium for heating compressed air at 107), according to this embodiment, it is compressed in the primary heater 105 and the secondary heater 107 As a heat medium for heating air, waste heat discharged from the cement production plant 200 may be directly used.

The cement production plant 200 of the present embodiment includes a preheating tower 201 preheating before calcining a mixed raw material such as limestone, iron oxide, and the like as a main raw material; A kiln (klin) 202 for producing a clinker, an intermediate product of cement, by heating the mixed raw material preheated in the preheating tower 201; And a clinker cooler 203 that cools the clinker.

The preheating tower 201, the kiln 202, and the clinker cooler 203 of this embodiment may be applied in the same manner as the first embodiment described above.

The cold heat medium for cooling the high temperature clinker in the clinker cooler 203 of the present embodiment may be compressed air transferred from the liquid air regasification apparatus 100.

According to this embodiment, as shown in FIG. 2, the air line AL is connected from the rear end of the secondary turbine-generator 108 to the cold heat medium inlet of the clinker cooler 203, and the secondary turbine-generator ( Compressed air discharged after driving 108) is supplied to the clinker cooler 203 to supply cold heat to cool the clinker.

However, unlike the first embodiment, which uses compressed air discharged by increasing the temperature after cooling the clinker from the clinker cooler 203 as a heat medium for heating the working fluid in the Rankine cycle 300, in this embodiment, The compressed air discharged from the clinker cooler 203 is compressed air supplied from the primary heater 105 and/or the secondary heater 107 of the liquid air regasification apparatus 100 to the turbine-generators 106 and 108. It can be used as a heating medium.

According to the present embodiment, the air line AL is connected to the clinker cooler 203 from the rear end of the secondary turbine-generator 108, and the primary heater 105 and/or secondary heater from the clinker cooler 203 A second air discharge line (AL2) connected to (107); may further include.

The high-temperature compressed air discharged after cooling the clinker from the clinker cooler 203 is discharged along the second air discharge line AL2, and is supplied to the primary heater 105 and/or the secondary heater 107. .

The high temperature compressed air supplied to the primary heater 105 along the second air discharge line AL2 is a heat medium for heating compressed air supplied from the primary heater 105 to the primary turbine-generator 106. Is used.

The hot compressed air supplied to the secondary heater 107 along the second air discharge line AL2 is a heat medium for heating compressed air supplied from the secondary heater 107 to the secondary turbine-generator 108. Is used.

The compressed air discharged along the second air discharge line AL2 after the temperature is lowered while heating the compressed air in the primary heater 105 and the secondary heater 107 may be discharged into the atmosphere.

In addition, the compressed air discharged from the clinker cooler 203 of this embodiment may be used as a heating medium for heating the working fluid in the Rankine cycle 400 described later.

The Rankine cycle 400 of this embodiment includes: an organic medium turbine-generator 401 for driving a turbine using a gaseous working fluid and converting the driving force of the turbine into electric power to produce electric power; A condenser 402 condensing the working fluid discharged after driving the organic medium turbine-generator 401; An organic medium pump 403 that pressurizes a working fluid to be circulated from the condenser 402 to the organic medium turbine-generator 401; And an organic medium heater 404 for vaporizing the working fluid transferred from the organic medium pump 403 to the organic medium turbine-generator 401.

The working fluid of the Rankine cycle 400 of this embodiment may be an organic medium. That is, the Rankine cycle 400 of the present embodiment may be an organic Rankine cycle (ORC). The organic medium that is the working fluid of the organic Rankine cycle 400 may be an organic compound or a mixture of organic compounds that evaporate at a lower temperature than the steam that is the working fluid of the Rankine cycle of the first embodiment. The organic medium, which is the working fluid of the Rankine cycle 400 of this embodiment, is an organic medium turbine-generator 401, a condenser 402, an organic medium pump 403, and an organic medium line 404 connecting the organic medium heater 404. ), it is possible to produce power while circulating the Rankine cycle 400 through adiabatic changes and isostatic changes.

The condenser 402 of this embodiment may be connected to a cooling tower 407 that supplies cold heat for condensing the gaseous working fluid. That is, in the condenser 402, the working fluid in the gaseous state is condensed by the cooling water circulated from the cooling tower 407, and the cooling water whose temperature is increased while condensing the working fluid is supplied to the cooling tower 407 again to circulate by decreasing the temperature. Can.

The working fluid vaporized and heated by the organic medium heater 404 generates power while driving the turbine of the organic medium turbine-generator 401.

Further, according to the present embodiment, the heat medium for vaporizing the working fluid in the organic medium heater 404 of the Rankine cycle 400 may utilize waste heat discharged from the cement production plant 200.

The waste heat of various temperatures is discharged from the cement production plant 200. According to the present embodiment, the waste heat of various temperatures discharged from the cement production plant 200 can be recovered step by step using the Rankine cycle 400 to effectively utilize it. have.

The waste heat from the exhaust gas discharged from the preheating tower 201 of the cement production plant 200 of the present exemplary embodiment is applied to the working fluid supplied from the organic medium heater 404 of the Rankine cycle 400 to the organic medium turbine-generator 401. It is used as a vaporizing heat medium.

In addition, the waste heat discharged from the clinker cooler 203 of the cement production plant 200 of the present embodiment, the working fluid supplied from the organic medium heater 404 of the Rankine cycle 400 to the organic medium turbine-generator 401 It can be used as a vaporizing heat medium.

According to this embodiment, the exhaust line (EL) connected to the high temperature heat medium inlet of the organic medium heater 404 from the exhaust port of the preheating tower 301; And an inducing blower 406 for discharging the exhaust gas after heat exchange from the organic medium heater 404 to the outside.

In addition, the cooler exhaust line (EL1) that is directly connected from the clinker cooler (203) to the high-temperature heat medium inlet of the organic medium heater (404) or joined to the exhaust line (EL) from the clinker cooler (203) may further include.

That is, in this embodiment, the compressed air having a high temperature while cooling the clinker in the clinker cooler 203 is to be supplied as a heat medium of the primary heater 105 and the secondary heater 107 through the second air discharge line AL2. It may be supplied as a heat medium of the organic medium heater 404.

The process of recovering the waste heat of the existing cement production plant was a method of directly generating power by using the heat source of the exhaust gas discharged from the kiln, and this method is simple steam generation due to the high load fluctuation and the supply temperature of a wide range of heat sources. It was difficult to apply to, there was a problem that the efficiency is low.

However, according to the present invention, by sequentially recovering the waste heat of the cement production plant 200 using the Rankine cycle (300, 400), by using in the Rankine cycle (300, 400) and liquefied air regasification apparatus 100 , Can stably produce power.

In addition, by recovering the waste heat at different temperatures generated in various processes of the cement production plant 200 in stages, it is possible to effectively utilize the waste heat and minimize waste heat released into the atmosphere.

In particular, before heating the working fluid with high-temperature waste heat discharged from the clinker cooler 203, the working fluid is preheated by utilizing the exhaust gas from the preheating tower 201, so that the initial operating time leading to power generation can be shortened. have.

In addition, by cooling the clinker with compressed air discharged from the liquefied air regasifier 100 to recover waste heat from the cement production plant 200, no additional equipment such as a fan for heat source recovery is required, Plant operating costs can be reduced and power consumption can be reduced.

In addition, while it is possible to stably generate electricity by linking a number of processes, there is no additional emission of air pollutants such as carbon dioxide due to the process linkage, which is advantageous in terms of environment.

As described above, the embodiments according to the present invention have been looked at, and the fact that the present invention can be embodied in other specific forms without departing from the spirit or scope of the embodiments described above are those with ordinary knowledge in the art. It is self-evident. Therefore, the above-described embodiments are to be regarded as illustrative rather than restrictive, and accordingly, the present invention is not limited to the above description and may be changed within the scope of the appended claims and their equivalents.

100: liquid air regasification device
101: liquid air storage tank
103: regasifier
104: heat exchanger
105, 107: heater
106, 108: turbine-generator
200: cement production plant
201: Preheating tower
202: kiln
203: clinker cooler
300, 400: Rankine cycle
301, 401: working fluid turbine-generator
302, 402: revenge
303, 403: working fluid pump
304, 305, 404: working fluid heater
306, 406: Manned blower
407: cooling tower
AL: Air line
AL1, AL2: Air exhaust line
ML: refrigerant line
VL, OL: Working fluid line
VL1: Working fluid recovery line
EL: exhaust line
EL1: Cooler exhaust line

Claims (13)

A turbine-generator that generates power using regasified air;
A liquid air regasification device including the turbine-generator and revaporizing liquid air to produce electric power;
A preheating tower for heating the raw materials;
A cooler that cools the product produced by the heating using cold heat of compressed air at a low temperature discharged from the turbine-generator;
A product production plant including the preheating tower and a cooler, and producing a product including a heating and cooling process of a raw material; And
Including a working fluid turbine-generator for generating power using the working fluid, the Rankine cycle for generating additional power; includes,
The Rankine cycle,
It includes; a working fluid heater to vaporize the working fluid to be supplied to the working fluid turbine-generator using waste heat of exhaust gas discharged from the product production plant;
The liquid air regasification device,
An industrial plant further comprising a heater for heating the regasification air to be supplied to the turbine-generator by using compressed air heated from the cooler or the working fluid discharged from the working fluid turbine-generator as a heat source while cooling the product. Liquefied air regasification system. The method according to claim 1,
An exhaust line connecting the preheating tower and the working fluid heater, and transferring exhaust gas from the preheating tower to the working fluid heater; And
And an air line connecting the turbine-generator and the cooler and transferring compressed air from the turbine-generator to the cooler. A liquefied air regasification system in connection with an industrial plant. The method according to claim 1,
The Rankine cycle,
A condenser for condensing the working fluid discharged from the working fluid turbine-generator;
A working fluid pump that compresses the working fluid condensed in the condenser and circulates the working fluid heater;
A second working fluid heater that further heats a working fluid vaporized in the working fluid heater and supplied to the working fluid turbine-generator by using compressed air cooled and discharged from the cooler; And
It includes; a first air discharge line connecting the cooler and the second working fluid heater, and transferring compressed air discharged from the cooler to the second working fluid heater.
The liquid air regasification device,
Further comprising; a working fluid recovery line connected to the heater from the intermediate stage of the working fluid turbine-generator;
A liquefied air regasification system in connection with an industrial plant, which supplies the working fluid discharged from the intermediate stage of the working fluid turbine-generator as a heat source for heating compressed air in the heater. The method according to claim 3,
The Rankine cycle is a steam Rankine cycle using steam as a working fluid,
The working fluid recovery line,
A liquefied air regasification system associated with an industrial plant, further connected to the condenser from the heater, and recovering the working fluid discharged after heating compressed air in the heater to the condenser. The method according to claim 1,
The liquid air regasification device,
A second air discharge line connecting the cooler and the heater, and supplying hot compressed air discharged from the cooler as a heat source for heating the compressed air supplied to the turbine-generator; further comprising an industrial plant. Liquefied air regasification system. The method according to claim 5,
And a cooler exhaust line that joins compressed air discharged from the cooler to a preheating tower exhaust gas stream transferred to the working fluid heater, and further comprising a liquefied air regasification system associated with an industrial plant. The method according to claim 5 or 6,
The Rankine cycle is an organic Rankine cycle in which the working fluid is an organic compound, a liquefied air regasification system in connection with an industrial plant. The method according to claim 1,
The temperature of the compressed air discharged from the cooler is lower than the temperature of the exhaust gas discharged from the preheating tower, and the liquefied air regasification system associated with the industrial plant. A liquid air regasification process for generating electric power by revaporizing liquid air to drive a turbine;
A product production process for producing products by heating and cooling raw materials; And
Includes; Rankine cycle process for generating power by vaporizing the circulating working fluid to drive the turbine;
The waste heat of the exhaust gas discharged from the heating process of the product production process is supplied to the heat source for vaporizing the working fluid in the Rankine cycle,
The waste heat of the compressed air discharged from the liquid air regasification process is supplied as cold heat of the cooling process of the product production process,
A method of regasifying liquefied air in connection with an industrial plant, wherein the regasified air is heated by using compressed air heated while being used in the cooling process or the working fluid as a heat source to be supplied to a turbine for electric power production. The method according to claim 9,
The waste heat discharged from the cooling process of the product production process, supplying the working fluid supplied to the turbine of the Rankine cycle as a heat source for heating, liquefied air regasification method associated with an industrial plant. The method according to claim 10,
A method of re-liquefying liquefied air in connection with an industrial plant, by supplying a portion of the working fluid discharged from the intermediate stage of the turbine of the Rankine cycle to a heat source for heating regasification air supplied to the turbine of the liquid air regasification process. The method according to claim 11,
Condensing the working fluid whose temperature is lowered while heating the regasification air,
A method of regasifying liquefied air in connection with an industrial plant, where condensed working fluid is vaporized and recycled to the turbine of the Rankine cycle. The method according to claim 9,
A method of regasifying liquefied air in connection with an industrial plant, supplying some of the waste heat discharged from the cooling process of the product production process as a heat source for vaporizing the working fluid in the Rankine cycle.

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