EP3301269A1 - Energieumwandlungsverfahren und -system - Google Patents

Energieumwandlungsverfahren und -system Download PDF

Info

Publication number
EP3301269A1
EP3301269A1 EP16191160.7A EP16191160A EP3301269A1 EP 3301269 A1 EP3301269 A1 EP 3301269A1 EP 16191160 A EP16191160 A EP 16191160A EP 3301269 A1 EP3301269 A1 EP 3301269A1
Authority
EP
European Patent Office
Prior art keywords
processing medium
state
vapor state
medium
vapor
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP16191160.7A
Other languages
English (en)
French (fr)
Inventor
Christoph Wieland
Andreas Kohlhepp
Roberto PILI
Sebastian EYERER
Hartmut Spliethoff
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Technische Universitaet Muenchen
Original Assignee
Technische Universitaet Muenchen
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 Technische Universitaet Muenchen filed Critical Technische Universitaet Muenchen
Priority to EP16191160.7A priority Critical patent/EP3301269A1/de
Publication of EP3301269A1 publication Critical patent/EP3301269A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K19/00—Regenerating or otherwise treating steam exhausted from steam engine plant
    • F01K19/10—Cooling exhaust steam other than by condenser; Rendering exhaust steam invisible
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22G—SUPERHEATING OF STEAM
    • F22G5/00—Controlling superheat temperature
    • F22G5/12—Controlling superheat temperature by attemperating the superheated steam, e.g. by injected water sprays

Definitions

  • the present invention concerns an energy conversion method and system and in particular an energy conversion method and system which are based on a Clausius-Rankine cycle and more particular on an organic Rankine cycle.
  • Clausius-Rankine cycle processes and in particular organic Rankine cycle (ORC) processes are inter alia used in connection with heat recovery from low-temperature heat sources and in particular for generating work from such sources.
  • an energy conversion method is provided which is based on a Clausius-Rankine cycle and in particular on an organic Rankine cycle.
  • the energy conversion method proposed by the present invention comprises steps of
  • processing medium and working medium are used as synonyms in the sense of the present invention.
  • said step of continuously introducing said processing medium in said non-vapor state and/or in said cooled state is performed by at least one of spraying and injecting and/or by using said processing medium in said non-vapor state and/or in said cooled state in at least one form of a liquid state, a mist, a state of a dispersed fluid and a state with a temperature below the temperature of the expanded processing medium in said vapor state.
  • processing medium is a heat exchange medium, a dry or arid medium, a wet medium, an isentropic medium, pure fluids and/or mixtures thereof and/or comprises an organic compound or a plurality thereof.
  • wet medium as a processing or working medium might be advantageous only in connection with extreme superheating of the processing or working medium.
  • a particular simple and reliable processing scheme can be achieved if according to a preferred improvement of the method said processing medium in said non-vapor state and/or in said cooled state is provided by feeding back condensed processing medium from a downstream side of the condensing step, in particular from an exit of the condensing step.
  • said step of providing the processing medium carrying heat comprises at least one of the steps of preheating the processing medium and - in particular consecutively - evaporating the processing medium in order to form a vapor state thereof, in particular by using an external heat source. Because of the increased degree of efficiency, this allows the usage and evaluation of waste heat or of heat from the conversion of e.g. biomass, solar energy or any other source of heat from a low temperature source.
  • an energy conversion system is provided, which is configured to perform an energy conversion method based on a Clausius-Rankine cycle and in particular on an organic Rankine cycle and/or based on a method according to the present invention.
  • the system comprises means configured to provide a processing medium carrying heat and/or under high pressure and temperature with increased energy content, means configured to expand the processing medium in order to generate and extract work, thereby transferring - at least in part - the processing medium into a vapor state and in particular into a superheated vapor state, and means configured to condense - at least in part - the expanded processing medium in said vapor state, thereby cooling and transferring the processing medium into a fluid state.
  • means is provided which is configured to continuously introduce after the means for expanding and before and/or within the means for condensing processing medium in a non-vapor state and/or in a cooled state into the expanded processing medium in said vapor state to be condensed, thereby desuperheating the expanded processing medium in said vapor state.
  • said means for continuously introducing said processing medium in said non-vapor state and/or in said cooled state preferably is or comprises at least one of an injector and a sprayer.
  • a comparable compact structure for the configuration of the system according to the present invention can be achieved if said at least one of an injector and a sprayer is located at or in a junction of a conduit fluidly connecting the means for expanding and the means for condensing and/or at or in a junction of an entry of the means for condensing.
  • said means for continuously introducing the processing medium in said non-vapor state and/or in said cooled state comprises a conduit for supplying - in particular in a feedback manner - the processing medium in said non-vapor state and/or in said cooled state, by branching off from a conduit conveying the processing medium exiting from said means for condensing and/or either before or after a pump for driving the processing medium within said conduit.
  • said conduit of said means for continuously introducing the processing medium in said non-vapor state and/or in said cooled state comprises a pump and/or a control valve for controlling the supply of the processing medium in said non-vapor state and/or in said cooled state.
  • Said means for expanding the processing medium may be or comprise a turbine or other expansion device, in particular operatively connected to a generator.
  • said means for providing the processing medium may be a consecutive arrangement of a preheater and an evaporator, in particular connected to an external heat source and/or in separated or integrated form.
  • said means for condensing the processing medium may be or comprise a condenser, in particular with a heat exchanger connected to an external heat sink.
  • Figure 1 is a schematic view describing general aspects of an embodiment of the energy conversion system 1 according to the present invention.
  • the energy conversion system 1 as depicted in figure 1 majorly comprises means 10 for providing a processing medium 2 for instance in form of a liquid, a vapor, a gas or a combination thereof, followed by means 20 for expanding the processing medium 2 and coupled to a generator 30 by coupling means 31, followed by means 40 for condensing the processing medium 2.
  • All the means 10, 20, and 40 are consecutively interconnected by a conduit or pipe arrangement 60 having conduit or pipe sections 61, 62, 63, 64 and 65.
  • the first pipe section 61 defines a fluidic connection between the means 10 for providing the processing medium 2 and the means 20 for expanding the processing medium 2.
  • the second pipe section 62 gives a fluidic connection between the means 20 for expanding the processing medium 2 and the means 40 for condensing the processing medium 2.
  • the third and fourth pipe sections 63 and 64 establish a fluidic connection between the means 40 for expanding the processing medium 2 and the means 10 for providing the processing medium 2 - with a pump 50 connected therebetween - and thereby closing the processing cycle.
  • the pump 50 between the pipe sections 63 and 64 is configured to drive the processing medium 2 within the conduit arrangement 60.
  • the means 10 for providing the processing medium 2 may comprise at an upstream side a preheater 11 connected by a fifth pipe section 65 to an evaporator 12 which forms also a part of the means 10 for providing the processing medium 2.
  • the preheater 11 and the evaporator 12 may be formed as a single and integrated component.
  • conduits 13, 14 and 15 the evaporator 12 and the preheater 11 are coupled to an external heat source 16, which can be formed by an external heat exchange medium.
  • this particular arrangement in general coincides with the setup of a conventional energy conversion system 1' as shown in figure 10 .
  • the energy conversion system 1 according to the present invention shown in figure 1 additionally comprises means 70 for continuously introducing processing medium 2 in a non-vapor state and/or in a cooled state which comprises at least one injector 71 or sprayer 71 in the embodiment shown in figure 1 .
  • an injector 71 or a sprayer 71 is just an option which is mandatory.
  • a simple junction may be sufficient without any spray dispersion functionality or the like.
  • the injector 71 or sprayer 71 can be arranged such that introduction of the processing medium 2 in said non-vapor state and/or in said cooled state is achieved either at a first junction 81 at a downstream side of the means 20 for expanding the processing medium 2 and at an upstream side of the means 40 for condensing the processing medium 2. Therefore, in figure 1 the first junction 81 is situated within the second pipe section 62.
  • a second junction 82 might be used for continuously introducing the processing medium 2 in said non-vapor state and/or in said cooled state which is situated within a neighborhood of an entry or in the entry of the means 40 for condensing the processing medium 2, i.e. the condenser 40.
  • the condenser 40 as such is equipped with pipe sections 43, 44, and 45 for being connected to an external heat sink 46, for instance to a further and external heat exchange medium.
  • the energy conversion system 1 according to the present invention as shown in figure 1 is capable of continuously introducing the processing medium 2 in a non-vapor state and/or in a cooled state into the expanded processing medium 2 in said vapor state to be condensed in order to achieve desuperheating of the expanded processing medium 2 without the burden of conventional desuperheating processes and means to thereby achieve a higher degree of efficiency with reduced size and costs of the underlying processes and means.
  • FIGS 2 and 3 describe in a similar manner preferred embodiments of the energy conversion system 1 according to the present invention and exemplify in a more concrete manner how the continuous introduction of the processing medium 2 in said non-vapor state and/or in said cooled state may be achieved by means of a feedback process and structure.
  • Both embodiments are based on a configuration where the means 70 for continuously introducing the processing medium 2 in said non-vapor state and/or in said cooled state with its injector 71 or sprayer 71 is connected to the downstream sides of the means 20 for expanding the processing medium 2 in the second pipe section 62.
  • this is not mandatory.
  • a conduit 73 of the means 70 for continuously introducing the processing medium 2 in said non-vapor state and/or in said cooled state derives from the fourth pipe section 64 after the pump 50 at branch 74.
  • a control valve 76 is provided for controlling the operation of continuously introducing the processing medium 2 in said non-vapor state and/or in said cooled state.
  • said conduit 73 derives from the third pipe section 63 before the pump 50 at branch 75.
  • an optional pump 77 may be provided in the conduit 73 before the valve 76 under such circumstances.
  • figures 4 to 6 show diagrams 90 describing the temperature-entropy relationship of wet, dry and isentropic processing media 2, respectively, within particular ORC processes.
  • each diagram 90 to each abscissa 91 the entropy S and to each ordinate 92 the temperature T of the underlying processing medium 2 are applied thereby explaining the phase relationship by means of a temperature-entropy diagram.
  • the liquid-vapor or two-phase region borderline 93 divides the entire thermodynamic region into a two-phase region 101 of the liquid-vapor coexistence region below the bell shaped curve 93 and the single-phase regions 102 and 103 of the liquid phase and of the vapor phase, respectively.
  • the hatched area 94 with its boundary represents schematically the region for the ORC process.
  • the circle area 95 corresponds to an exemplary region of states of the processing medium 2 at the end of the expansion process.
  • FIGS 7 to 9 schematically depict aspects of desuperheating processes in a conventional condenser tube 41' of a conventional means 40' for condensing a processing medium 2, in a condenser tube 41 formed according to the present invention, and in a conventional condenser tube 41' modified according to the present invention by retrofit with inventive means for desuperheating by continuously introducing processing medium 2 in a non-vapor and/or in a cooled state, respectively.
  • the respective traces p', p represent the course of the respective pressure within the condenser tubes 41', 41 along the cubes' elongations 99', 99.
  • the diagram shows conventional phases 96', 97', and 98' for achieving desuperheating, condensation, and subcooling or supercooling, respectively.
  • the means 40 for condensing the processing medium 2 according to the present invention and its condenser pipe 41 show a phase 96 for desuperheating which corresponds to a fraction of the entire elongation 99 of the condenser pipe 41 which is below 10% thereof. Consequently, the entire elongation 99 of the condenser pipe 41 according to the present invention can be reduced when compared to the elongation 99' of the conventional condenser pipe 41'.
  • a conventional means 40' for condensing the processing medium 2 which has been modified by adopting means 70 with an injector 71 or sprayer 71 for continuously introducing processing medium 2 in said non-vapor state and/or in said cooled state.
  • This can be seen as a retrofit measure for an existing conventional condenser pipe 41'.
  • the fraction of the entire elongation 99' necessary for desuperheating and thus corresponding to the phase fraction 96 shown in figure 9 are remarkably reduced when compared to the situation shown in figure 7 and also indicated in figure 9 by a dotted line.
  • the condensation pressure is reduced from the pressure p' to p leading to an increasing power output of the expander.
  • the degree of efficiency is increased due to the provided means of the present invention enabling a continuous introduction of the processing medium 2 in a non-vapor and/or in a cooled state for enhancing the desuperheating process.
  • the present invention concerns the technical field of power engineering and energy management. In particular aspects of increasing the effectiveness and decreasing the costs in regard to ORC systems are concerned.
  • the efficiency of the cycle process underlying the ORC arrangement and a reduction of the investment costs can be achieved.
  • the improvements are not strictly related to a turbine or the provision of any other expansion machine.
  • the improvements are also independent from the processing medium involved, being a dry or arid medium or an isentropic medium, and also from the underlying concept of the power plant in question.
  • the means and methods for injection or spray desuperheating at an upstream side or at the entry of a condensing process or means yields and improved heat transfer.
  • lowering the condensation pressure is a benefit, thereby increasing efficiency and performance of the underlying expansion process and machine.
  • the proposed technology according to the present invention may reduce the amount of heat transfer surfaces of the involved condensers, thereby reducing the overall costs of the apparatus.
  • the standard ORC process is a Rankine process in its simplest form and comprises as shown in figure 10 a pre-heater 11, an evaporator 12, and a condenser 40 as heat exchanging means, a turbine 20 or a general expansion machine, and a pump 50. These aspects have a high degree of similarity to former times' steam power plants.
  • Working or processing media 2 for the ORC technology can be characterized according to their entropy-temperature diagrams as shown in connection with figures 4 to 6 .
  • Such processing media 2 can be classified as being (i) dry or arid media, for instance R22, (ii) wet media, for instance water or isopentane, and (iii) and isentropic media, for instance R245fa.
  • the two-phase region 101 is situated below the bell shaped curve 93 and in this region the steam or vapor phase and the liquid phase coexist.
  • the hatched area 94 schematically indicates the ORC cycle process performed by the apparatus 1' as shown in figure 10 .
  • the state after the expansion is indicated by the circle 95.
  • the expansion after the turbine or general expansion machine 20 ends with superheated vapor in the region indicated by the circle 95.
  • the endpoint of the expansion process may be located directly within the wet vapor or wet steam region, i.e. within the two-phase region 101.
  • the saturated vapor or steam curve 93 is isentropic, thereby corresponding to a constant entropy.
  • the expansion ends directly on the saturated vapor or steam curve 93.
  • an efficient means and process for desuperheating are proposed. This is achieved by using - in a continuous manner and after the expansion process and before or at the beginning of or within/during condensation - the introduction of the processing medium 2 in a non-vapor and/or in a cooled state, for instance by injecting, spraying or the like and/or by using the processing medium 2 in form of a liquid, a mist, a state of a dispersed fluid or the like.
  • the inventive method for desuperheating will be referred to in the following as injection cooling.
  • the proposed means and method according to the present invention use desuperheating by continuously introducing the processing medium 2 in a non-vapor state and/or in a cooled state in order to improve the ORC process.
  • a conventional horizontal condenser pipe 41' underlying the conventional condenser 40' is used.
  • the superheated vapor 2 first of all is desuperheated before it can condense in the two-phase region at constant temperature.
  • the liquid 2 as such may also be used in a subcooled or supercooled state. This takes place majorly at the end of the condenser 40', i.e. in the neighborhood of its exit and in the region of the liquid phase.
  • injection cooling according to the present invention may also be used in apparatuses and plants which already exist, i.e. in the sense of a retrofitting measure.
  • the condensation pressure can be lowered as indicated in figure 9 .
  • FIGS 2 and 3 more explicitly show embodiments of the present invention being integrated in the ORC process.
  • Means and processes for injection cooling as such are already known in the prior art. However, they are used for temperature regulation and reduction of specific enthalpy after adiabatic restriction or throttling or in a temporary manner only.
  • the present invention suggests a continuous injection cooling, i.e. a continuous introduction of the processing medium 2 in a non-vapor state and/or in a cooled state, and in particular after a polytropic expansion with extraction of work, wherein in contrast to the conventional case the saturation region cannot be reached due to pure physical reasons despite the polytropic reduction of pressure. Therefore, negative properties of the still superheated processing fluid or medium 2 regarding the heat transfer capabilities within the condenser 40 can be avoided according to the present invention yielding remarkably improved properties with the saturated fluid or processing medium 2.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)
EP16191160.7A 2016-09-28 2016-09-28 Energieumwandlungsverfahren und -system Withdrawn EP3301269A1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP16191160.7A EP3301269A1 (de) 2016-09-28 2016-09-28 Energieumwandlungsverfahren und -system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP16191160.7A EP3301269A1 (de) 2016-09-28 2016-09-28 Energieumwandlungsverfahren und -system

Publications (1)

Publication Number Publication Date
EP3301269A1 true EP3301269A1 (de) 2018-04-04

Family

ID=57211250

Family Applications (1)

Application Number Title Priority Date Filing Date
EP16191160.7A Withdrawn EP3301269A1 (de) 2016-09-28 2016-09-28 Energieumwandlungsverfahren und -system

Country Status (1)

Country Link
EP (1) EP3301269A1 (de)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4693086A (en) * 1984-10-15 1987-09-15 Hitachi, Ltd. Steam turbine plant having a turbine bypass system
US4847525A (en) * 1986-05-27 1989-07-11 Solmecs Corporation, N.V. Methods and systems for magnetohydrodynamic power conversion
US5570579A (en) * 1991-07-11 1996-11-05 High Speed Tech Oy Ltd. Method and apparatus for improving the efficiency of a small-size power plant based on the ORC process
US20070245733A1 (en) * 2005-10-05 2007-10-25 Tas Ltd. Power recovery and energy conversion systems and methods of using same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4693086A (en) * 1984-10-15 1987-09-15 Hitachi, Ltd. Steam turbine plant having a turbine bypass system
US4847525A (en) * 1986-05-27 1989-07-11 Solmecs Corporation, N.V. Methods and systems for magnetohydrodynamic power conversion
US5570579A (en) * 1991-07-11 1996-11-05 High Speed Tech Oy Ltd. Method and apparatus for improving the efficiency of a small-size power plant based on the ORC process
US20070245733A1 (en) * 2005-10-05 2007-10-25 Tas Ltd. Power recovery and energy conversion systems and methods of using same

Similar Documents

Publication Publication Date Title
US8166761B2 (en) Method and system for generating power from a heat source
CN1993536B (zh) 用于执行热力学循环的方法和装置
Yoon et al. Performance characteristics of a high-efficiency R717 OTEC power cycle
RU2561221C2 (ru) Система прямого испарения и способ для систем с циклом ренкина на органическом теплоносителе
CN111022137B (zh) 基于有机朗肯循环和有机闪蒸循环的余热回收系统及方法
US20140000261A1 (en) Triple expansion waste heat recovery system and method
CN104141582B (zh) 高压液体做功式有机朗肯循环发电系统
US20170002695A1 (en) Organic rankine binary cycle power generation system
CN105209724A (zh) 具有三级膨胀的容积式能量回收系统
Ma et al. Principle investigation on advanced absorption power generation cycles
KR101683714B1 (ko) 초임계 이산화탄소 랭킨 사이클을 이용한 지열 발전 시스템
US8474262B2 (en) Advanced tandem organic rankine cycle
KR20180102379A (ko) 초임계 랭킨 사이클 기반의 열기관 및 이 열기관의 동작방법
EP3301269A1 (de) Energieumwandlungsverfahren und -system
US9739179B2 (en) Working fluid for a device, device and method for converting heat into mechanical energy
Özdemir et al. Energy and exergy analysis of an organic Rankine Cycle Using different working Fluids from Waste Heat Recovery
US8739535B2 (en) Fluid feedback pump to improve cold start performance of organic rankine cycle plants
US11802494B2 (en) Optimized cascade organic Rankine cycle
CN208749417U (zh) 双热源有机朗肯循环发电系统
RU2686541C1 (ru) Парогазовая установка
Tuo Thermodynamic and Economic Analysis of Reheat Transcritical Organic Rankine Power Cycle Using a Low Temperature Geothermal Heat Source
Yazdi Comparing the efficiency of two different models of combined parallel flash binary cycles
Lefebvre et al. Carnot cycle in practice: compensating inefficiencies of ORC expanders through thermal regeneration
RU2606847C1 (ru) Способ преобразования низкопотенциальной тепловой энергии
Yazdi INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY INVESTIGATION OF DIFFERENT MODELS OF COMBINED PARALLEL FLASH BINARY CYCLES

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20171212

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

17Q First examination report despatched

Effective date: 20180504

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20190918