WO2015059547A1 - Method and device for recovering energy from damp exhaust gases - Google Patents

Method and device for recovering energy from damp exhaust gases Download PDF

Info

Publication number
WO2015059547A1
WO2015059547A1 PCT/IB2014/002186 IB2014002186W WO2015059547A1 WO 2015059547 A1 WO2015059547 A1 WO 2015059547A1 IB 2014002186 W IB2014002186 W IB 2014002186W WO 2015059547 A1 WO2015059547 A1 WO 2015059547A1
Authority
WO
WIPO (PCT)
Prior art keywords
exhaust gas
heat exchanger
condensate
direct contact
cooled
Prior art date
Application number
PCT/IB2014/002186
Other languages
French (fr)
Inventor
Elias BOULAWZ KSAYER
Denis Clodic
Urs Andreas Herzog
Thomas LAMARE
Samer MAALOUF
Thomas Weimer
Original Assignee
Holcim Technology Ltd
Armines
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Holcim Technology Ltd, Armines filed Critical Holcim Technology Ltd
Priority to EP14809087.1A priority Critical patent/EP3060529B1/en
Publication of WO2015059547A1 publication Critical patent/WO2015059547A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B7/00—Hydraulic cements
    • C04B7/36—Manufacture of hydraulic cements in general
    • C04B7/43—Heat treatment, e.g. precalcining, burning, melting; Cooling
    • C04B7/47—Cooling ; Waste heat management
    • C04B7/475—Cooling ; Waste heat management using the waste heat, e.g. of the cooled clinker, in an other way than by simple heat exchange in the cement production line, e.g. for generating steam
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J15/00—Arrangements of devices for treating smoke or fumes
    • F23J15/06—Arrangements of devices for treating smoke or fumes of coolers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/002—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by condensation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
    • F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
    • F23G5/44—Details; Accessories
    • F23G5/46—Recuperation of heat
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B7/00—Rotary-drum furnaces, i.e. horizontal or slightly inclined
    • F27B7/20—Details, accessories, or equipment peculiar to rotary-drum furnaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D17/00—Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
    • F27D17/004—Systems for reclaiming waste heat
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2290/00—Organisational aspects of production methods, equipment or plants
    • C04B2290/20—Integrated combined plants or devices, e.g. combined foundry and concrete plant
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00—Combustion technologies with mitigation potential
    • Y02E20/30—Technologies for a more efficient combustion or heat usage
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
    • Y02P40/121—Energy efficiency measures, e.g. improving or optimising the production methods

Definitions

  • the invention relates to a method for recovering energy from damp exhaust gases having a temperature from 90-130 °C and a dew point from 50-75 °C.
  • the invention further relates to a device for carrying out said method.
  • exhaust gas streams are generated from which it seems economically reasonable to recover heat.
  • Such gas streams are for example the stream of exhaust gas exiting the raw meal preheater, which after flowing through the raw meal mill at a temperature between 90 and 150 °C has a . dew point from 50 to 80 °C at ambient pressure due to the moisture content of the raw meal.
  • the exhaust gas from a slag drying unit may also be cited in this context, typically having a temperature from 90 to 120 °C and a dew point from 50 to 80 °C at ambient pressure.
  • Damp, low- temperature exhaust gases of such kind contain not only a usable quantity of sensible heat, but also a not inconsiderable amount of latent heat, which can be recovered. Due to the low temperature level of the exhaust gas stream, the economic viability of recovering energy depends to a decisive degree on the efficiency of the recovery method.
  • the invention is particularly concerned with the recovery of energy from damp exhaust gases having a temperature lower than 130 °C.
  • exhaust gases is understood to mean not only exhaust gases from combustion processes, but aerosols in general, that is to say mixtures of solid or liquid particles in suspension in a gas.
  • An exhaust gas is therefore also understood to refer to exhaust air that does not originate from a combustion process, for example.
  • the object of the present invention is therefore to use damp exhaust gases or damp exhaust air having a temperature from 90 to 130 °C and a water dew point from 50 to ' 75 °C (measured under ambient pressure) in order to recover the sensible and the latent heat content thereof.
  • damp exhaust gases or damp exhaust air having a temperature from 90 to 130 °C and a water dew point from 50 to ' 75 °C (measured under ambient pressure) in order to recover the sensible and the latent heat content thereof.
  • the invention provides that exhaust gas having a temperature from 90 to 130 °C and a water dew point from 50-75 °C is first cooled to a temperature above the dew point in an indirect, first heat exchanger, and the cooled exhaust gas is then passed through a direct contact condenser, wherein the condensate that forms in the direct contact condenser is collected and heated in the first heat exchanger by the exchange of heat with the exhaust gas.
  • the invention thus provides a two- stage heat recovery process, in which in a first step only the sensible heat of the exhaust gas stream is used in an indirect heat exchanger, and the latent heat content is recovered in a direct contact condenser afterwards.
  • the indirect heat exchanger and the direct contact condenser are connected in series, so that the damp exhaust gas first passes through the indirect heat exchanger and then through the direct contact condenser. Since the damp exhaust gas is cooled to a temperature that is above the dew point in the indirect heat exchanger, condensation and the corrosion problems associated therewith are avoided. The damp exhaust gas is not cooled to a temperature below the dew point until it reaches the direct contact condenser, so that the water content contained in the exhaust gas condenses there, and the corresponding condensation heat may be used subsequently.
  • direct contact condenser is understood to be a condensation unit in which a coolant comes into direct contact with the exhaust gas.
  • the coolant is typically sprayed into a chamber through which the exhaust gas passes, so that an exceedingly large surface is available for heat transfer.
  • the coolant is usually sprayed from the upper end of the chamber, and the exhaust gas is introduced into the chamber at the opposite, lower end and normally flows through the chamber from the bottom upwards.
  • the condensate that forms in the direct contact condenser is collected on the floor of the chamber and drained off.
  • the coolant used is preferably water at a temperature below the water dew point of the exhaust gas.
  • the condensate that collects in the condenser is at a higher temperature than the initial state thereof that exists while spraying is carried out.
  • the condensate that is formed in the direct contact condenser is used as the coolant for the first heat exchanger, in which it is heated further as the exhaust gas is cooled.
  • the heat exchanger has the form of an indirect heat exchanger so that any direct contact between the coolant and the exhaust gas is avoided. Both streams are thus separated physically by at least one heat-permeable wall.
  • the exhaust gas and the coolant preferably flow through the indirect heat exchanger in countercurrent flow.
  • the indirect heat exchanger can preferably be designed as a plate heat exchanger, a spiral heat exchanger or a tube heat exchanger.
  • a unique feature of the invention is that the same coolant is used in the direct contact condenser and in the indirect heat exchanger, to extract both the sensible and the latent heat content of the exhaust gas.
  • a further advantage consists in that the direct contact condenser may be used as a flue gas scrubber at the same time.
  • the final result is that it is possible to use the maximum enthalpy, that is to say the maximum possible energy at the highest possible temperature level of a stream of damp exhaust gas.
  • the method is preferably carried out in such manner that in the first heat exchanger heated condensate is cooled to a temperature lower than the water dew point of the exhaust gas and then introduced, particularly sprayed, into the direct contact condenser.
  • the coolant emerging from the indirect heat exchanger particularly water, is preferably at a temperature from 70 to 95 °C.
  • the heat content of the coolant may be used in a wide variety of ways. However, due to the relatively low temperature level of the coolant it cannot be used to generate electricity straight away without certain further steps.
  • One preferred refinement therefore provides that the heated condensate is cooled in a second heat exchanger, in which a working fluid from a thermodynamic cycle is evaporated.
  • thermodynamic cycle is preferably designed as a gas turbine process, so that the thermal energy content of the coolant can easily be converted into mechanical energy, and then successfully into electrical energy.
  • thermodynamic cycle is particularly preferred to design the thermodynamic cycle as an Organic Rankine Cycle.
  • the particularity of this thermodynamic cycle is that it uses a working fluid other than steam.
  • the Organic Rankine Cycle (ORC) method is used most often when the available temperature gradient between the heat source and the heat sink is too small to allow the operation of a steam-driven turbine.
  • Possible working media are for example ammonia, R12, HFC-245fa, HFC-245ca, Rll or HFC-236fa, or mixtures thereof.
  • the method according to the invention is particularly suitable for use in recovering energy from the exhaust gas generated in a raw meal mill of a cement manufacturing plant or from the exhaust air from a slag drying unit of a cement manufacturing plant.
  • the invention relates to a device for recovering energy from damp exhaust gases, comprising an indirect, first heat exchanger, into which exhaust gas may be introduced via a feed line and from which the cooled exhaust gas may be removed via an extraction line, and a direct contact condenser, to which the cooled exhaust gas may be fed from the first heat exchanger and which comprises a spraying apparatus for spraying coolant and a condensate line for removing the condensate that forms, wherein the condensate may be fed to the first heat exchanger via the condensate line as a coolant for cooling the exhaust gas.
  • the return line is designed to return the condensate from the first heat exchanger to the spraying apparatus of the direct contact condenser.
  • the return line may pass through a second heat exchanger, wherein the second heat exchanger is provided for cooling the condensate that has been heated in the first heat exchanger down to a temperature that is lower than the water dew point of the exhaust gas.
  • thermodynamic cycle in order to perform the thermodynamic cycle a system is provided that comprises the second heat exchanger for evaporating a working fluid of the thermodynamic cycle.
  • reference numeral 1 designates a water circuit as the coolant circuit for direct contact condenser 2 and indirect heat exchanger 3.
  • the coolant water in the cooling circuit is fed to direct contact condenser 2 by means of a pump 4 and is sprayed inside direct contact condenser 2 by means of a spraying apparatus 5.
  • the condensate 6 that collects on the bottom of direct contact condenser 2 is forwarded by a pump 7 as the coolant to indirect heat exchanger 3, which is preferably designed as a tube heat exchanger.
  • the damp exhaust gas is introduced in the direction indicated by arrow 8 at a temperature between 90 and 130 °C, and first flows through indirect heat exchanger 3, in which the temperature in countercurrent flow to the cooling water is heated to a temperature of 70 °C, for example, but at all events above the water dew point of the exhaust gas, thereby warming the cooling water.
  • the warmed exhaust gas is then forwarded to direct contact condenser 2 and passes through the condenser from the bottom upwards, exiting direct contact condenser 2 through discharge line 9.
  • direct contact condenser 2 the warmed exhaust gas comes into contact with the sprayed cooling water, and the water vapour contained in the exhaust gas condenses as it heats the cooling water.
  • sulphur, chlorine, dust or other solids may also be separated from the exhaust gas in direct contact condenser 2.
  • Coolant circuit 1 further comprises a heat exchanger 10, which is integrated in a thermodynamic cycle 11.
  • heat exchanger 10 serves to evaporate the working fluid contained in thermodynamic cycle 11, wherein a quantity of heat is extracted from the cooling water to such a degree that when the cooling water is forwarded to direct contact condenser 2 it is at a temperature below the dew point of the exhaust gas.
  • Thermodynamic cycle 11 is configured for example as an Organic Rankine Cycle (ORC) , wherein for example HFC-245fa is selected as the working fluid.
  • ORC Organic Rankine Cycle
  • the working fluid is evaporated in heat exchanger 10 and allowed to expand in steam turbine 12, wherein the mechanical energy generated thereby may be converted into electrical energy in an electric generator 13.
  • the condenser in thermodynamic cycle 11 is designated by reference numeral 14.
  • the working fluid that is liquefied in condenser 14 is subsequently compressed in compressor 15.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)

Abstract

In a method for recovering energy from damp exhaust gases, in which exhaust gas having a temperature from 90-130 °C and a water dew point from 50-75°C is first cooled to a temperature above the dew point in an indirect, first heat exchanger (3) and the cooled exhaust gas is then passed through a direct contact condenser (2), the condensate (6) that is formed in the direct contact condenser (2) is collected and heated in the first heat exchanger (3) by heat exchange with the exhaust gas.

Description

Method and device for recovering energy from damp exhaust gases
The invention relates to a method for recovering energy from damp exhaust gases having a temperature from 90-130 °C and a dew point from 50-75 °C.
The invention further relates to a device for carrying out said method.
In industrial processes, streams of exhaust gases are generated at various temperature levels. A number of different heat recovery methods have already been suggested for using the heat energy contained in the exhaust gas streams. Particularly when exhaust gas streams at temperatures above 300 °C are involved, the recovery of heat from such streams is associated with significant financial benefits, wherein use is typically made of conventional heat exchangers in which heat can be transferred from the hot exhaust gas stream to another medium.
In order to use the latent heat in an exhaust gas stream, methods have also been suggested for condensing exhaust gas, particularly in firing plants in which damp fuels are burned, so that the exhaust gas stream has a correspondingly high steam content.
In a cement manufacturing plant, exhaust gas streams are generated from which it seems economically reasonable to recover heat. For example, it is generally standard practice to make the used air from the clinker cooler available as tertiary air to a secondary firing system of the cement manufacturing plant. In the past, however, less attention has been paid to the use of relatively damp, low temperature exhaust gas streams in a cement clinker production plant for energy recovery purposes. Such gas streams are for example the stream of exhaust gas exiting the raw meal preheater, which after flowing through the raw meal mill at a temperature between 90 and 150 °C has a . dew point from 50 to 80 °C at ambient pressure due to the moisture content of the raw meal. The exhaust gas from a slag drying unit may also be cited in this context, typically having a temperature from 90 to 120 °C and a dew point from 50 to 80 °C at ambient pressure. Damp, low- temperature exhaust gases of such kind contain not only a usable quantity of sensible heat, but also a not inconsiderable amount of latent heat, which can be recovered. Due to the low temperature level of the exhaust gas stream, the economic viability of recovering energy depends to a decisive degree on the efficiency of the recovery method.
The invention is particularly concerned with the recovery of energy from damp exhaust gases having a temperature lower than 130 °C. For the purpose of the invention, the term exhaust gases is understood to mean not only exhaust gases from combustion processes, but aerosols in general, that is to say mixtures of solid or liquid particles in suspension in a gas. An exhaust gas is therefore also understood to refer to exhaust air that does not originate from a combustion process, for example.
The object of the present invention is therefore to use damp exhaust gases or damp exhaust air having a temperature from 90 to 130 °C and a water dew point from 50 to ' 75 °C (measured under ambient pressure) in order to recover the sensible and the latent heat content thereof. In this context, it should be possible in particular to use exhaust gas and exhaust air streams from cement clinker manufacturing plants as efficiently as possible. In particular, by this means it should be possible to use them to generate electricity.
In order to solve this object, in a method of the kind described in the introduction the invention provides that exhaust gas having a temperature from 90 to 130 °C and a water dew point from 50-75 °C is first cooled to a temperature above the dew point in an indirect, first heat exchanger, and the cooled exhaust gas is then passed through a direct contact condenser, wherein the condensate that forms in the direct contact condenser is collected and heated in the first heat exchanger by the exchange of heat with the exhaust gas. The invention thus provides a two- stage heat recovery process, in which in a first step only the sensible heat of the exhaust gas stream is used in an indirect heat exchanger, and the latent heat content is recovered in a direct contact condenser afterwards. In this process, the indirect heat exchanger and the direct contact condenser are connected in series, so that the damp exhaust gas first passes through the indirect heat exchanger and then through the direct contact condenser. Since the damp exhaust gas is cooled to a temperature that is above the dew point in the indirect heat exchanger, condensation and the corrosion problems associated therewith are avoided. The damp exhaust gas is not cooled to a temperature below the dew point until it reaches the direct contact condenser, so that the water content contained in the exhaust gas condenses there, and the corresponding condensation heat may be used subsequently.
In this context, the term direct contact condenser is understood to be a condensation unit in which a coolant comes into direct contact with the exhaust gas. The coolant is typically sprayed into a chamber through which the exhaust gas passes, so that an exceedingly large surface is available for heat transfer. The coolant is usually sprayed from the upper end of the chamber, and the exhaust gas is introduced into the chamber at the opposite, lower end and normally flows through the chamber from the bottom upwards. The condensate that forms in the direct contact condenser is collected on the floor of the chamber and drained off.
The coolant used is preferably water at a temperature below the water dew point of the exhaust gas. As a consequence of the condensation heat, the condensate that collects in the condenser is at a higher temperature than the initial state thereof that exists while spraying is carried out.
According to the invention, the condensate that is formed in the direct contact condenser is used as the coolant for the first heat exchanger, in which it is heated further as the exhaust gas is cooled.
The heat exchanger has the form of an indirect heat exchanger so that any direct contact between the coolant and the exhaust gas is avoided. Both streams are thus separated physically by at least one heat-permeable wall. In this case, the exhaust gas and the coolant preferably flow through the indirect heat exchanger in countercurrent flow. The indirect heat exchanger can preferably be designed as a plate heat exchanger, a spiral heat exchanger or a tube heat exchanger.
A unique feature of the invention is that the same coolant is used in the direct contact condenser and in the indirect heat exchanger, to extract both the sensible and the latent heat content of the exhaust gas. A further advantage consists in that the direct contact condenser may be used as a flue gas scrubber at the same time.
The final result is that it is possible to use the maximum enthalpy, that is to say the maximum possible energy at the highest possible temperature level of a stream of damp exhaust gas.
The method is preferably carried out in such manner that in the first heat exchanger heated condensate is cooled to a temperature lower than the water dew point of the exhaust gas and then introduced, particularly sprayed, into the direct contact condenser. This enables the coolant to be transported in a circuit. The coolant emerging from the indirect heat exchanger, particularly water, is preferably at a temperature from 70 to 95 °C. The heat content of the coolant may be used in a wide variety of ways. However, due to the relatively low temperature level of the coolant it cannot be used to generate electricity straight away without certain further steps. One preferred refinement therefore provides that the heated condensate is cooled in a second heat exchanger, in which a working fluid from a thermodynamic cycle is evaporated. The thermodynamic cycle is preferably designed as a gas turbine process, so that the thermal energy content of the coolant can easily be converted into mechanical energy, and then successfully into electrical energy. In order to address the low temperature level of the coolant effectively, it is particularly preferred to design the thermodynamic cycle as an Organic Rankine Cycle. The particularity of this thermodynamic cycle is that it uses a working fluid other than steam. The Organic Rankine Cycle (ORC) method is used most often when the available temperature gradient between the heat source and the heat sink is too small to allow the operation of a steam-driven turbine. Possible working media are for example ammonia, R12, HFC-245fa, HFC-245ca, Rll or HFC-236fa, or mixtures thereof.
As was indicated previously, the method according to the invention is particularly suitable for use in recovering energy from the exhaust gas generated in a raw meal mill of a cement manufacturing plant or from the exhaust air from a slag drying unit of a cement manufacturing plant.
According to another aspect, the invention relates to a device for recovering energy from damp exhaust gases, comprising an indirect, first heat exchanger, into which exhaust gas may be introduced via a feed line and from which the cooled exhaust gas may be removed via an extraction line, and a direct contact condenser, to which the cooled exhaust gas may be fed from the first heat exchanger and which comprises a spraying apparatus for spraying coolant and a condensate line for removing the condensate that forms, wherein the condensate may be fed to the first heat exchanger via the condensate line as a coolant for cooling the exhaust gas.
It is preferably provided that the return line is designed to return the condensate from the first heat exchanger to the spraying apparatus of the direct contact condenser. In particular, the return line may pass through a second heat exchanger, wherein the second heat exchanger is provided for cooling the condensate that has been heated in the first heat exchanger down to a temperature that is lower than the water dew point of the exhaust gas.
It is preferably further provided that in order to perform the thermodynamic cycle a system is provided that comprises the second heat exchanger for evaporating a working fluid of the thermodynamic cycle.
In the following, the invention will be explained in greater detail with reference to an embodiment thereof, which is represented schematically in the drawing. In the drawing, reference numeral 1 designates a water circuit as the coolant circuit for direct contact condenser 2 and indirect heat exchanger 3. The coolant water in the cooling circuit is fed to direct contact condenser 2 by means of a pump 4 and is sprayed inside direct contact condenser 2 by means of a spraying apparatus 5. The condensate 6 that collects on the bottom of direct contact condenser 2 is forwarded by a pump 7 as the coolant to indirect heat exchanger 3, which is preferably designed as a tube heat exchanger. The damp exhaust gas is introduced in the direction indicated by arrow 8 at a temperature between 90 and 130 °C, and first flows through indirect heat exchanger 3, in which the temperature in countercurrent flow to the cooling water is heated to a temperature of 70 °C, for example, but at all events above the water dew point of the exhaust gas, thereby warming the cooling water. The warmed exhaust gas is then forwarded to direct contact condenser 2 and passes through the condenser from the bottom upwards, exiting direct contact condenser 2 through discharge line 9. In direct contact condenser 2, the warmed exhaust gas comes into contact with the sprayed cooling water, and the water vapour contained in the exhaust gas condenses as it heats the cooling water. Optionally, sulphur, chlorine, dust or other solids may also be separated from the exhaust gas in direct contact condenser 2.
Coolant circuit 1 further comprises a heat exchanger 10, which is integrated in a thermodynamic cycle 11. In this context, heat exchanger 10 serves to evaporate the working fluid contained in thermodynamic cycle 11, wherein a quantity of heat is extracted from the cooling water to such a degree that when the cooling water is forwarded to direct contact condenser 2 it is at a temperature below the dew point of the exhaust gas.
Thermodynamic cycle 11 is configured for example as an Organic Rankine Cycle (ORC) , wherein for example HFC-245fa is selected as the working fluid. The working fluid is evaporated in heat exchanger 10 and allowed to expand in steam turbine 12, wherein the mechanical energy generated thereby may be converted into electrical energy in an electric generator 13. The condenser in thermodynamic cycle 11 is designated by reference numeral 14. The working fluid that is liquefied in condenser 14 is subsequently compressed in compressor 15.

Claims

Claims :
1. Method for recovering energy from damp exhaust gases, in which exhaust gas having a temperature of 90-130 °C and a water dew point of 50-75 °C is first cooled to a temperature above the dew point in an indirect, first heat exchanger (3), and the cooled exhaust gas is then passed through a direct contact condenser (2), wherein the condensate (6) that forms in the direct contact condenser (2) is collected and heated in the first heat exchanger (3) by the exchange of heat with the exhaust gas.
2. The method according to claim 1, characterized in that the condensate (6) heated in the first heat exchanger (3) is cooled to a temperature that is lower than the water dew point of the exhaust gas and then introduced into the direct contact condenser (2) as the coolant, particular by spraying .
3. The method according to claim 2, characterized in that the heated condensate (6) is cooled in a second heat exchanger (10), in which a working fluid from a thermodynamic cycle (11) is evaporated.
4. The method according to claim 3, characterized in that the thermodynamic cycle (11) is designed as a gas turbine process.
5. The method according to claim 3, characterized in that the thermodynamic cycle (11) is designed as an Organic Rankine Cycle.
6. The method according to any of claims 1 to 5, characterized in that exhaust gas from a cement manufacturing plant is used as the damp exhaust gas.
7. The method according to any of claims 1 to 6, characterized in that exhaust gas from a raw meal mill in a cement manufacturing plant is used as the damp exhaust gas.
8. The method according to any of claims 1 to 6, characterized in that exhaust air from a slag drying unit in a cement manufacturing plant is used as the damp exhaust gas .
9. Device for recovering energy from damp exhaust gases, particularly for carrying out the method according to any of claims 1 to 8, comprising an indirect, first heat exchanger (3) , into which exhaust gas may be introduced via a feed line and from which the cooled exhaust gas may be removed via an extraction line (9), and a direct contact condenser (2), to which the cooled exhaust gas may be fed from the first heat exchanger (3) and which comprises a spraying apparatus (5) for spraying coolant and a condensate line for removing the condensate (6) formed thereby, wherein the condensate (6) may be fed to the first heat exchanger (3) via the condensate line as a coolant for cooling the exhaust gas.
10. The device according to claim 9, characterized in that a return line is provided for returning the condensate (6) from the first heat exchanger (3) to the spraying apparatus (5) of the direct contact condenser (2) .
11. The device according to claim 10, characterized in that the return line passes through a second heat exchanger
(10) , wherein the second heat exchanger (10) is provided to cool the condensate (6) that is heated in the first heat exchanger (3) down to a temperature that is below the water dew point of the exhaust gas.
12. The device according to claim 11, characterized in that a system is provided for carrying out a thermodynamic cycle (11), and comprises the second heat exchanger (10) for evaporating a working fluid of the thermodynamic cycle
(11) .
13. The device according to claim 12, characterized in that the thermodynamic cycle (11) is designed as a gas turbine process.
14. The device according to claim 12, characterized in that the thermodynamic cycle (11) is designed as an Organic Rankine Cycle.
PCT/IB2014/002186 2013-10-22 2014-10-22 Method and device for recovering energy from damp exhaust gases WO2015059547A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP14809087.1A EP3060529B1 (en) 2013-10-22 2014-10-22 Method and device for recovering energy from damp exhaust gases

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ATA816/2013A AT514579B1 (en) 2013-10-22 2013-10-22 Method and apparatus for recovering energy from wet exhaust gases
ATA816/2013 2013-10-22

Publications (1)

Publication Number Publication Date
WO2015059547A1 true WO2015059547A1 (en) 2015-04-30

Family

ID=52014153

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2014/002186 WO2015059547A1 (en) 2013-10-22 2014-10-22 Method and device for recovering energy from damp exhaust gases

Country Status (3)

Country Link
EP (1) EP3060529B1 (en)
AT (1) AT514579B1 (en)
WO (1) WO2015059547A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4011850A1 (en) 2020-12-09 2022-06-15 Holcim Technology Ltd Method of producing clinker form cement raw meal
CN114777473A (en) * 2022-05-16 2022-07-22 江西云泰铜业有限公司 Thorough dross removal device of step furnace for brass production
WO2023056495A1 (en) * 2021-10-04 2023-04-13 Scheuch Management Holding GmbH Process and plant for producing cement clinker

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3045900A1 (en) * 1980-12-05 1982-07-08 Babcock-BSH AG vormals Büttner-Schilde-Haas AG, 4150 Krefeld Washing waste gases and plant - using condensate from waste gas as cleaning liq. after reheating to dew-point
US7814742B2 (en) * 2006-12-13 2010-10-19 Mitsubishi Heavy Industries, Ltd. Integrated coal gasification combined cycle plant
FI121216B (en) * 2008-06-30 2010-08-31 Cuycha Innovation Oy Process for dissolving carbon dioxide from flue gas or other gas and neutralizing the acidity of the solution obtained

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
"Free Waste Heat Recovery Consulting Service", 30 June 2013 (2013-06-30), XP055171715, Retrieved from the Internet <URL:http://www.heatcatcher.com/wp-content/uploads/2013/06/Press-Pack-2013.pdf> [retrieved on 20150224] *
"Waste Heat Recovery in a lime Plant", ZKG, no. 6, 30 June 2013 (2013-06-30), XP002736381, Retrieved from the Internet <URL:http://www.zkg.de/en/artikel/zkg_Waste_heat_recovery_in_a_lime_plant_1741589.html> [retrieved on 20150224] *
DARREN BRYANT: "Good Return on Investments Using ORC's to Generate Power & Save Cooling Costs", CEMPOWER 2013, 5 June 2013 (2013-06-05), XP055171706, Retrieved from the Internet <URL:http://www.heatcatcher.com/wp-content/uploads/2013/06/Heatcatcher-CEMPOWER-2013-Presentation.pdf> [retrieved on 20150224] *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4011850A1 (en) 2020-12-09 2022-06-15 Holcim Technology Ltd Method of producing clinker form cement raw meal
WO2022123435A1 (en) 2020-12-09 2022-06-16 Holcim Technology Ltd Method of producing clinker from cement raw meal
WO2023056495A1 (en) * 2021-10-04 2023-04-13 Scheuch Management Holding GmbH Process and plant for producing cement clinker
CN114777473A (en) * 2022-05-16 2022-07-22 江西云泰铜业有限公司 Thorough dross removal device of step furnace for brass production
CN114777473B (en) * 2022-05-16 2023-11-14 江西云泰铜业有限公司 Slag removing device of stepping furnace for thoroughly removing slag in brass production

Also Published As

Publication number Publication date
EP3060529B1 (en) 2017-12-06
AT514579A4 (en) 2015-02-15
EP3060529A1 (en) 2016-08-31
AT514579B1 (en) 2015-02-15

Similar Documents

Publication Publication Date Title
Jouhara et al. Waste heat recovery technologies and applications
US8176738B2 (en) Method and system for converting waste heat from cement plant into a usable form of energy
CN106196892B (en) Lignite drying using closed loop heat pump
EP3060529B1 (en) Method and device for recovering energy from damp exhaust gases
EP3106750A1 (en) Lignite drying in a lignite fired power plant with a heat pump
CN102466414A (en) Method for recycling heat and water of steam evaporated during drying of fuel coal in power plant
EP1532360B1 (en) A method and a device for production of mechanical work and cooling/heating in conjunction with a combustion machine
CN105636672B (en) SOx and CO is removed from flue gas2Method and apparatus
Nandakishora et al. Review on waste heat recovery from flue gas and its application in CO2 capture
Saidawat et al. Power generation from waste heat extracted through clinker production in cement industry
RU2562730C1 (en) Utilisation method of thermal energy generated by thermal power plant
RU2552481C1 (en) Operating method of thermal power plant
RU2562745C1 (en) Utilisation method of heat energy generated by thermal power plant
RU2559655C1 (en) Method of operation of thermal power plant
RU2570943C2 (en) Method of operation of thermal power plant
Maalouf Study and design of a thermodynamic system generating mechanical work from a hot source at 120 C
RU2564470C2 (en) Operating method of thermal power plant
RU2570961C2 (en) Method of operation of thermal power plant
RU2569292C1 (en) Method of recovery of heat energy generated by thermal power station
RU2555600C1 (en) Operating method of thermal power plant
RU2560504C1 (en) Heat power plant operation mode
RU2562736C1 (en) Utilisation method of thermal energy generated by thermal power plant
RU2562728C1 (en) Utilisation method of thermal energy generated by thermal power plant
RU2562741C1 (en) Utilisation method of thermal energy generated by thermal power plant
RU2560513C1 (en) Heat power plant operation mode

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14809087

Country of ref document: EP

Kind code of ref document: A1

DPE1 Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101)
REEP Request for entry into the european phase

Ref document number: 2014809087

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2014809087

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE