中低温地热工质梯级利用ORC磁悬浮发电***Medium and low temperature geothermal working medium cascade utilization ORC maglev power generation system
技术领域Technical field
本发明涉及地热能发电技术领域,尤其涉及中低温地热工质梯级利用ORC磁悬浮发电***。The invention relates to the technical field of geothermal energy power generation, in particular to an ORC magnetic levitation power generation system using a cascade of medium and low temperature geothermal working fluids.
背景技术Background technique
随着化石能源的逐渐枯竭,地热能因其储量丰富、分布广泛、稳定性好、不受季节、环境、气候、昼夜等外界因素干扰等优点成为未来绿色能源利用中颇具竞争力的一员。我国地热能储量丰富,年可开采量折合相当于标准煤26亿吨,其中超过70%可开采资源属于中低温地热资源。但是,中低温地热资源作为低品位能源,开发利用难度大,目前主要以直接热利用为主,如温泉、供暖等。部分地区采用有机朗肯循环(ORC),利用低沸点的有机工质进行中低温地热汽轮机发电,但是电效率低下(不足10%)制约着中低温地热发电利用的推广。中低温地热资源发电效率低下(不足10%)制约着其发电利用的推广。With the gradual depletion of fossil energy, geothermal energy has become a competitive player in the future use of green energy due to its abundant reserves, wide distribution, good stability, and freedom from interference from external factors such as seasons, environment, climate, day and night. my country is rich in geothermal energy reserves, with an annual mineable amount equivalent to 2.6 billion tons of standard coal, of which more than 70% of the mineable resources belong to medium and low temperature geothermal resources. However, as a low-grade energy source, the development and utilization of medium and low temperature geothermal resources is difficult. At present, direct heat utilization is mainly used, such as hot springs and heating. Organic Rankine Cycle (ORC) is used in some areas to use low-boiling organic working fluids for low- and medium-temperature geothermal turbine power generation, but the low electrical efficiency (less than 10%) restricts the promotion of medium and low-temperature geothermal power generation. The low power generation efficiency (less than 10%) of medium and low temperature geothermal resources restricts the promotion of its power generation utilization.
因此,现有技术还有待于改进和发展。Therefore, the existing technology needs to be improved and developed.
发明内容Summary of the invention
鉴于上述现有技术的不足,本发明的目的在于提供中低温地热工质梯级利用ORC磁悬浮发电***,旨在解决现有利用中低温地热发电效率低下的问题。In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide an ORC magnetic levitation power generation system using a cascade of medium and low temperature geothermal working fluids, aiming to solve the problem of low efficiency of the existing medium and low temperature geothermal power generation.
本发明为解决上述技术问题所采用的技术方案如下:The technical solutions adopted by the present invention to solve the above technical problems are as follows:
中低温地热工质梯级利用ORC磁悬浮发电***,其中,包括:The medium and low temperature geothermal working medium cascade use ORC magnetic levitation power generation system, which includes:
ORC发电机组,包括一级ORC发电机组以及二级ORC发电机组;ORC generator set, including the first level ORC generator set and the second level ORC generator set;
所述一级ORC发电机组包括,用于对第一工质加压的第一循环泵,用于蒸发第一工质的一级蒸发器,与所述一级蒸发器连接的一级发电机,与所述一级发电机连接的用于蒸发第二工质的二级蒸发器;The one-stage ORC generator set includes a first circulating pump for pressurizing a first working fluid, a first-stage evaporator for evaporating the first working fluid, and a first-stage generator connected to the first-stage evaporator , A secondary evaporator for evaporating a second working fluid connected to the primary generator;
所述二级ORC发电机组包括,用于对第二工质加压的第二循环泵,所述二级蒸发器,与所述二级蒸发器连接的二级发电机,与所述二级发电机连接的第一冷凝器。The two-stage ORC generator set includes a second circulating pump for pressurizing a second working fluid, the two-stage evaporator, a two-stage generator connected to the two-stage evaporator, and the second The first condenser connected to the generator.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述一级ORC发电机组还包括,用于给经与二级蒸发器换热降温后的第一工质进行第二级降温的吸收式制冷装置。The medium and low temperature geothermal working medium cascade use ORC magnetic levitation power generation system, wherein, the first-stage ORC generator set further includes a second-stage cooling for the first working medium after heat exchange with the secondary evaporator and cooling The absorption refrigeration unit.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述吸收式制冷装置包括:In the medium and low temperature geothermal working medium cascade utilization ORC magnetic levitation power generation system, wherein the absorption refrigeration device includes:
用于第三工质浓缩的发生器,与所述发生器连接的第二冷凝器、与所述二级蒸发器连接 的第三冷凝器以及与所述第三冷凝器连接的吸收器;A generator for concentrating the third working fluid, a second condenser connected to the generator, a third condenser connected to the secondary evaporator, and an absorber connected to the third condenser;
所述发生器第一出口与所述第二冷凝器第一入口连接,所述第二冷凝器第一出口与所述第三冷凝器的第一入口连接,所述第三冷凝器的第一出口与所述吸收器第一入口连接;The first outlet of the generator is connected with the first inlet of the second condenser, the first outlet of the second condenser is connected with the first inlet of the third condenser, and the first inlet of the third condenser is connected. The outlet is connected with the first inlet of the absorber;
所述二级蒸发器第一出口与所述第三冷凝器第二入口连接;所述第三冷凝器第二出口经所述第一循环泵与所述一级蒸发器入口连接;The first outlet of the two-stage evaporator is connected with the second inlet of the third condenser; the second outlet of the third condenser is connected with the inlet of the first-stage evaporator through the first circulating pump;
所述吸收器第一出口与所述发生器入口连接,所述发生器第二出口与所述吸收器第二入口连接。The first outlet of the absorber is connected with the inlet of the generator, and the second outlet of the generator is connected with the second inlet of the absorber.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述一级发电机以及所述二级发电机均为磁悬浮透平发电机。In the medium and low temperature geothermal working medium cascade utilization ORC maglev power generation system, wherein the first-stage generator and the second-stage generator are both magnetic levitation turbine generators.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述第一工质的沸点高于所述第二工质的沸点。The medium and low temperature geothermal working fluid cascade utilizes ORC magnetic levitation power generation system, wherein the boiling point of the first working fluid is higher than the boiling point of the second working fluid.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述第二工质为R123或R124。The medium and low temperature geothermal working fluid cascade utilizes ORC magnetic levitation power generation system, wherein the second working fluid is R123 or R124.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述第二冷凝器与所述第三冷凝器之间设置有节流阀。The medium and low temperature geothermal working medium cascade use ORC magnetic levitation power generation system, wherein a throttle valve is arranged between the second condenser and the third condenser.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述吸收器出口与发生器之间设置有第三循环泵。The medium and low temperature geothermal working medium cascade uses ORC magnetic levitation power generation system, wherein a third circulation pump is arranged between the outlet of the absorber and the generator.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述第三工质为二元工质。The medium and low temperature geothermal working fluid cascade utilizes ORC magnetic levitation power generation system, wherein the third working fluid is a binary working fluid.
所述的中低温地热工质梯级利用ORC磁悬浮发电***,其中,所述第三工质为溴化锂溶液。The medium and low temperature geothermal working medium cascade uses the ORC magnetic levitation power generation system, wherein the third working medium is a lithium bromide solution.
有益效果:本发明所提供的中低温地热工质梯级利用ORC磁悬浮发电***,通过工质以及地热能梯级利用有效提高了中低温地热热量利用效率,提升了地热发电总量。Beneficial effects: The medium and low temperature geothermal working medium cascade utilization ORC magnetic levitation power generation system provided by the present invention effectively improves the medium and low temperature geothermal heat utilization efficiency through the working medium and the geothermal energy cascade utilization, and increases the total amount of geothermal power generation.
附图说明Description of the drawings
图1是本发明实施实例提供的第一种中低温地热工质梯级利用ORC磁悬浮发电***框图。Fig. 1 is a block diagram of a first medium-low temperature geothermal working medium cascade utilization ORC magnetic levitation power generation system provided by an embodiment of the present invention.
图2是本发明实施实例提供的第二种中低温地热工质梯级利用ORC磁悬浮发电***框图。Fig. 2 is a block diagram of a second medium-low temperature geothermal working medium cascade utilization ORC magnetic levitation power generation system provided by an embodiment of the present invention.
具体实施方式Detailed ways
为使本发明的目的、技术方案及优点更加清楚、明确,以下参照附图并举实施例对本发明进一步详细说明。应当理解,此处所描述的具体实施例仅仅用以解释本发明,并不用于限定本发明。In order to make the objectives, technical solutions and advantages of the present invention clearer and clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention.
如图1所示,本发明公开的中低温地热工质梯级利用ORC磁悬浮发电***,所述ORC发电机组包括两组即一级ORC发电机组和二级ORC发电机组,其中,所述一级ORC发电机组包括一级蒸发器10、与所述一级蒸发器10连接的一级发电机101、与所述一级发电机101连接的二级蒸发器20,所述一级发电机101为磁悬浮透平发电机,与所述二级蒸发器20以及所述一级蒸发器10连接的第一循环泵102。As shown in Fig. 1, the medium and low temperature geothermal working medium cascade use ORC magnetic levitation power generation system disclosed by the present invention, the ORC generator set includes two groups, namely a first-stage ORC generator set and a second-stage ORC generator set, wherein the first-stage ORC The generator set includes a primary evaporator 10, a primary generator 101 connected to the primary evaporator 10, and a secondary evaporator 20 connected to the primary generator 101. The primary generator 101 is a magnetic suspension A turbo generator, a first circulating pump 102 connected to the two-stage evaporator 20 and the one-stage evaporator 10.
具体来说,所述一级ORC发电机组发电过程涉及一级有机朗肯循环,即中低温地热水经过一级蒸发器10,使经过一级蒸发器的第一工质吸收热量后蒸发,形成高温高压蒸汽,高温高压蒸汽进入一级磁悬浮透平发电机101中膨胀做功带动一级磁悬浮发电机发电,一级磁悬浮发电机出口乏汽随后进入二级蒸发器20冷凝并为二级有机朗肯循环提供热量,冷凝后液态工质通过第一循环泵102,回到一级蒸发器10。Specifically, the power generation process of the first-stage ORC generator set involves a first-stage organic Rankine cycle, that is, the medium and low-temperature geothermal water passes through the first-stage evaporator 10, so that the first working fluid passing through the first-stage evaporator absorbs heat and evaporates. High-temperature and high-pressure steam is formed. The high-temperature and high-pressure steam enters the first-stage maglev turbine generator 101 to expand and do work to drive the first-stage maglev generator to generate electricity. The exhaust steam at the outlet of the first-stage maglev generator then enters the second-stage evaporator 20 to condense and become a second-stage organic The Ken cycle provides heat, and the liquid working fluid after condensation passes through the first circulating pump 102 and returns to the first-stage evaporator 10.
所述二级ORC发电机组包括,所述二级蒸发器20,与所述二级蒸发器20连接的二级发电机201,分别与所述二级蒸发器20以及所述二级发电机201连接的第一冷凝器202;所述二级发电机201为磁悬浮透平发电机。The two-stage ORC generator set includes, the two-stage evaporator 20, a two-stage generator 201 connected to the two-stage evaporator 20, and the two-stage evaporator 20 and the two-stage generator 201 respectively. The first condenser 202 is connected; the secondary generator 201 is a magnetic levitation turbine generator.
具体来说,所述二级有机朗肯循环,即第二有机工质在所述二级蒸发器20中吸收从一级磁悬浮发电机101出口排出乏汽中的热能蒸发为第二有机工质蒸汽,随后具有较高温度和压力的第二有机工质蒸汽进入二级磁悬浮发电机201中膨胀做功带动二级磁悬浮发电机发电,二级磁悬浮发电机201出口乏汽进入第一冷凝器202中冷凝最终冷凝后液态第二有机工质,通过第二工质泵203回到所述二级蒸发器20中。通过增设二级ORC发电机组,使一级ORC发电机组中发电后的蒸汽再次利用,提高了热量的利用效率。Specifically, the second organic Rankine cycle, that is, the second organic working medium absorbs the heat energy in the exhaust steam discharged from the outlet of the primary magnetic levitation generator 101 in the second evaporator 20 and evaporates into the second organic working medium The steam, and then the second organic working fluid steam with higher temperature and pressure enters the secondary magnetic levitation generator 201 to expand and do work to drive the secondary magnetic levitation generator to generate electricity. The exhaust steam at the outlet of the secondary magnetic levitation generator 201 enters the first condenser 202 After condensing and finally condensing, the liquid second organic working fluid is returned to the secondary evaporator 20 through the second working fluid pump 203. By adding a two-stage ORC generator set, the steam generated in the first-stage ORC generator set can be reused, which improves the efficiency of heat utilization.
请参阅图2,在一些实施方式中,为了提高热量的利用率,在一级ORC发电机组中增加一个吸收式制冷装置,为所述经过与二级蒸发器换热降温后的第一工质进行二次降温。所述吸收式制冷装置包括依次循环连接的第三冷凝器30、吸收器303、第三循环泵304、发生器40、第二冷凝器301、以及节流阀302。所述发生器包括用于蒸汽排出的第一出口,用于浓缩后的工质浓缩液排出的第二出口,用于稀释后的液态工质进入的入口。所述第二冷凝器为水冷冷凝器,其包括工质管路以及冷水管路,所述工质管路包括第一入口和第一出口。所述第三冷凝器包括用于第一工质的流通的第一工质管道,用于第三工质蒸汽的流通的第三工质管道,所述第三工质管道,包括第一入口和第一出口,所述第一工质管道包括第二入口和第二出口。所述吸收器包括供从第三冷凝器冷凝后的液态工质进入的第一入口,供从所述发生器浓缩后的浓缩液进入的第二入口。Referring to Figure 2, in some embodiments, in order to improve the utilization rate of heat, an absorption refrigeration device is added to the first-stage ORC generator set, which is the first working fluid after heat exchange and cooling with the second-stage evaporator Perform a second cooling. The absorption refrigeration device includes a third condenser 30, an absorber 303, a third circulating pump 304, a generator 40, a second condenser 301, and a throttle valve 302 that are cyclically connected in sequence. The generator includes a first outlet for discharging steam, a second outlet for discharging concentrated working fluid, and an inlet for diluting liquid working fluid. The second condenser is a water-cooled condenser, which includes a working fluid pipeline and a cold water pipeline, and the working fluid pipeline includes a first inlet and a first outlet. The third condenser includes a first working fluid pipeline for the circulation of a first working fluid, a third working fluid pipeline for the circulation of a third working fluid steam, and the third working fluid pipeline includes a first inlet And a first outlet, the first working fluid pipeline includes a second inlet and a second outlet. The absorber includes a first inlet for the liquid working fluid condensed from the third condenser to enter, and a second inlet for the concentrated liquid concentrated from the generator to enter.
所述发生器40的第一出口与所述第二冷凝器301第一入口连接,所述发生器40的第二 出口与所述吸收器303的第二入口连接;所述第二冷凝器301第一出口通过节流阀302与所述第三冷凝器的第一入口连接,所述第三冷凝器30的第一出口与所述吸收器303第一入口连接;所述吸收器303的出口通过第三循环泵304与所述发生器40的入口连接;The first outlet of the generator 40 is connected to the first inlet of the second condenser 301, and the second outlet of the generator 40 is connected to the second inlet of the absorber 303; the second condenser 301 The first outlet is connected to the first inlet of the third condenser through a throttle valve 302, and the first outlet of the third condenser 30 is connected to the first inlet of the absorber 303; the outlet of the absorber 303 Connect with the inlet of the generator 40 through the third circulating pump 304;
所述二级蒸发器20的第一工质出口与所述第三冷凝器第二入口连接;所述第三冷凝器第二出口经所述第一循环泵102与所述一级蒸发器10的入口连接。需要说明的是上述所述的“第一”、“第二”、“出口”、“入口”仅用于表述的方便,并不具有特殊含义,也不用于限定。The first working fluid outlet of the two-stage evaporator 20 is connected to the second inlet of the third condenser; the second outlet of the third condenser is connected to the first-stage evaporator 10 via the first circulating pump 102 The entrance connection. It should be noted that the above-mentioned “first”, “second”, “outlet”, and “entry” are only used for convenience of expression, and do not have special meanings, nor are they used for limitation.
具体来说,从一级蒸发器10中排出的具有余温的地热水通入发生器40,将发生器40中的二元工质浓缩(所述二元工质为两种不同沸点工质的混合溶液,例如溴化锂溶液),二元工质在发生器40中分离,低沸点的工质气化后进入第二冷凝器301,剩余高浓度的二元工质浓缩液通入吸收器303中。低沸点的工质蒸汽在第二冷凝器301中液化,液化后的低沸点工质经节流阀302降压后通入所述第三冷凝器30,此时第三冷凝器30中的压力低于所述低沸点工质的饱和压力而蒸发吸热,冷却一级ORC循环中经与二级蒸发器换热降温后的第一工质。随后低沸点工质蒸汽被送入所述吸收器303中,在吸收器303中与所述高浓度浓缩液混合,混合后的溶液经第三循环泵304加压后被送到所述发生器40。通过增设吸收式制冷装置,不但使一级ORC循环中的第一工质做功前后的温差增大,还能利用从一级蒸发器排出的地热水的余热,提高了地热发电的发电功率和地热能的利用效率。Specifically, the geothermal water with residual temperature discharged from the primary evaporator 10 is passed into the generator 40, and the binary working fluid in the generator 40 is concentrated (the binary working fluid is two working fluids with different boiling points). The binary working medium is separated in the generator 40, the low-boiling working medium is gasified and then enters the second condenser 301, and the remaining high-concentration binary working medium concentrate is passed to the absorber 303 in. The low boiling point working fluid vapor is liquefied in the second condenser 301, and the liquefied low boiling point working fluid is reduced in pressure by the throttle valve 302 and then passed into the third condenser 30. At this time, the pressure in the third condenser 30 It evaporates and absorbs heat below the saturation pressure of the low boiling point working fluid, and cools the first working fluid after heat exchange with the secondary evaporator in the first-stage ORC cycle to cool down. Then the low boiling point working fluid vapor is sent to the absorber 303, where it is mixed with the high-concentration concentrated liquid in the absorber 303, and the mixed solution is pressurized by the third circulation pump 304 and then sent to the generator 40. By adding an absorption refrigeration device, not only the temperature difference before and after the first working fluid in the first-stage ORC cycle is increased, but also the waste heat of the geothermal water discharged from the first-stage evaporator can be used to increase the power and power of geothermal power generation. Utilization efficiency of geothermal energy.
需要说明的是上述三个循环之间并非孤立运行,而是相互耦合、相互联系。所述二级蒸发器不仅是一级有机朗肯循环的冷凝器,同时也是二级有机朗肯循环的蒸发器,通过二级蒸发器将传统发电机***中本该传递到大气环境中的具有余温乏汽的热量继续用于发电,提高中低温地热能的利用率,进而提高发电效率,增加发电量。吸收式制冷循环可以使吸收式制冷循环产生的冷量用于降低有机朗肯循环的冷凝温度和冷凝压力,从而增大磁悬浮发电机进出口两端的温差和压差,提高发电机的发电功率,进而增加发电量以及提高中低温地热能的利用效率。It should be noted that the above three cycles do not operate in isolation, but are coupled and interconnected with each other. The two-stage evaporator is not only the condenser of the first-stage organic Rankine cycle, but also the evaporator of the second-stage organic Rankine cycle. Through the second-stage evaporator, the traditional generator system is transferred to the atmosphere. The heat of the waste steam will continue to be used for power generation to increase the utilization rate of medium and low temperature geothermal energy, thereby improving power generation efficiency and increasing power generation. The absorption refrigeration cycle can use the cold energy generated by the absorption refrigeration cycle to reduce the condensation temperature and condensation pressure of the organic Rankine cycle, thereby increasing the temperature and pressure difference between the inlet and outlet of the magnetic levitation generator, and increasing the power generation of the generator. This will increase power generation and improve the efficiency of low- and medium-temperature geothermal energy utilization.
综上所述,本发明提供了一种中低温地热工质梯级利用ORC磁悬浮发电***,所述中低温地热工质梯级利用ORC磁悬浮发电***,其包括ORC发电机组,以及吸收式制冷装置,所述ORC发电机组包括一级ORC发电机组和二级ORC发电机组。本发明中中低温地热水依次经过一级有机朗肯循环的蒸发器和吸收式制冷的发生器。其中吸收式制冷发生器利用从一级有机郎肯循环的蒸发器排放的具有余温地热水中获得的热量用于吸收式制冷来提升发电循环效率,实现了地热能的梯级利用。In summary, the present invention provides a medium-low temperature geothermal working medium cascade using ORC maglev power generation system, which includes an ORC generator set and an absorption refrigeration device. The ORC generator set includes a primary ORC generator set and a secondary ORC generator set. In the present invention, the medium and low temperature geothermal water sequentially passes through the evaporator of the first-stage organic Rankine cycle and the generator of absorption refrigeration. Among them, the absorption refrigeration generator uses the heat obtained from the hot water with residual temperature discharged from the evaporator of the first-stage organic Rankine cycle for absorption refrigeration to improve the efficiency of the power generation cycle and realize the cascade utilization of geothermal energy.
本发明中的透平发电机并非传统的汽轮发电机,而是磁悬浮汽轮发电机,在本文中简称 磁悬浮发电机。磁悬浮发电机采用的是磁悬浮轴承,转子与轴承之间不相互接触,因此机械摩擦小,发电机的转速高,从而提高发电效率。The turbo-generator in the present invention is not a traditional steam turbine generator, but a magnetic levitation turbine generator, which is referred to as a magnetic levitation generator in this text. The magnetic levitation generator uses magnetic levitation bearings, and the rotor and the bearing do not contact each other, so the mechanical friction is small and the generator speed is high, thereby improving the power generation efficiency.
应当理解的是,本发明的应用不限于上述的举例,对本领域普通技术人员来说,可以根据上述说明加以改进或变换,所有这些改进和变换都应属于本发明所附权利要求的保护范围。It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or changes can be made based on the above description, and all these improvements and changes should fall within the protection scope of the appended claims of the present invention.