WO2014048089A1 - 自然循环间接式烟气再热器 - Google Patents

自然循环间接式烟气再热器 Download PDF

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Publication number
WO2014048089A1
WO2014048089A1 PCT/CN2013/072586 CN2013072586W WO2014048089A1 WO 2014048089 A1 WO2014048089 A1 WO 2014048089A1 CN 2013072586 W CN2013072586 W CN 2013072586W WO 2014048089 A1 WO2014048089 A1 WO 2014048089A1
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Prior art keywords
heat
section
flue gas
temperature
flue
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PCT/CN2013/072586
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English (en)
French (fr)
Inventor
钱学略
Original Assignee
上海伏波环保设备有限公司
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Publication date
Priority claimed from CN 201220497055 external-priority patent/CN202813409U/zh
Priority claimed from CN201210364365.3A external-priority patent/CN103672936B/zh
Application filed by 上海伏波环保设备有限公司 filed Critical 上海伏波环保设备有限公司
Priority to DE112013004744.6T priority Critical patent/DE112013004744B4/de
Priority to KR1020157008908A priority patent/KR101668969B1/ko
Priority to JP2015533411A priority patent/JP5898382B2/ja
Publication of WO2014048089A1 publication Critical patent/WO2014048089A1/zh
Priority to US14/669,010 priority patent/US9291348B2/en

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Classifications

    • 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
    • F23J15/08—Arrangements of devices for treating smoke or fumes of heaters
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D19/00—Regenerative heat-exchange apparatus in which the intermediate heat-transfer medium or body is moved successively into contact with each heat-exchange medium
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F27/00—Control arrangements or safety devices specially adapted for heat-exchange or heat-transfer apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F27/00—Control arrangements or safety devices specially adapted for heat-exchange or heat-transfer apparatus
    • F28F27/02—Control arrangements or safety devices specially adapted for heat-exchange or heat-transfer apparatus for controlling the distribution of heat-exchange media between different channels
    • 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

Definitions

  • the invention relates to the field of re-heating of net flue gas after wet desulfurization, in particular to a natural circulation indirect flue gas reheater. Background technique
  • the flue gas of the boiler contains sulfur dioxide, which will cause acid rain and cause serious environmental pollution.
  • sulfur dioxide treatment of thermal power plants has attracted wide attention.
  • domestic power plants have now adopted effective devices for sulfur dioxide treatment.
  • the most widely used desulfurization method in China is flue gas wet desulfurization, especially limestone (or lime)-gypsum wet desulfurization.
  • Limestone (or lime) - Gypsum wet desulfurization is the use of limestone (or lime) as an absorbent to scrub the sulfur dioxide in the flue gas to form calcium sulfite, and then react with the added air to form gypsum, remove sulfur dioxide, purify the flue gas. .
  • the entire reaction process is carried out in a desulfurization absorption tower, and the reaction temperature is generally about 50 °C.
  • the permanent gas-gas heat exchanger (GGH) in the limestone (or lime)-gypsum wet desulfurization system the specific role of the gas-gas heat exchanger: First, the heat of the flue gas entering the desulfurization tower is absorbed, and the desulfurization tower is lowered into the desulfurization tower.
  • the flue gas temperature optimizes the operating conditions of the desulfurization tower; the second is to use the absorbed flue gas heat to heat the net flue gas behind the desulfurization absorber tower, increase the exhaust gas temperature (generally required not less than 80 ° C), and reduce the flue Corrosion of low-temperature wet flue gas with bacon, and at the same time, the flue gas at the exit of the chimney has sufficient elevation to improve the environmental quality of the surrounding atmosphere.
  • the GGH device process currently applied on the market is shown in Figure 1.
  • the flue gas before the desulfurization tower 1 and the net flue gas after the desulfurization tower are directly exchanged by the rotary heat exchanger 4, and the endothermic net flue gas enters the chimney 5
  • the high temperature flue 2 is arranged vertically parallel to the low temperature flue 3 (net flue gas flue).
  • the rotary heat exchanger Due to the limitations of the structure of the rotary heat exchanger, its sealing performance is not good, and it is easy to leak during the operation process, causing the sulfur dioxide to escape, so that the desulfurization efficiency is reduced, and even the emission is not up to standard, the rotary heat exchanger
  • the structure is shown in Figure 2.
  • the flue gas contains sulfur dioxide, which forms sulfuric acid with the water vapor in the flue gas when the flue gas temperature is lower than a certain temperature, which will corrode the equipment, so whether it is the cooling of the upstream side of the desulfurization absorber tower
  • the heater is also a heater on the downstream side, and there is a problem of acid dew corrosion.
  • the corrosion of the GGH components and the blockage of the heat exchange components will reduce the availability of the wet desulfurization system and increase the maintenance cost of the GGH. Therefore, some wet desulfurization systems choose not to install GGH, and direct wet bacon runs, but it will produce problems of smoke and rain and white smoke.
  • Japan's low-temperature electric dust removal technology also solves the problem of wet chimney after desulfurization to some extent.
  • the system has three parts: "heat recovery device + electric precipitator + reheater", heat recovery unit (MGGH-H/E) Between the air preheater and the inlet end of the electrostatic precipitator, the reheater (MGGH-R/E) is placed on the flue between the wet desulfurization and the chimney.
  • the technology works by using thermal media. (usually an aqueous medium) and the flue gas exchange heat through the heat recovery unit and the reheater, so that the operating temperature of the electric precipitator is lowered from the normal low temperature state (130 to 140 ° C) to a low temperature state (90 to 100).
  • Chinese patent ZL200610169891.9 discloses an evaporative cooling flue gas heater, which is also a heat exchanger replacing the conventional GGH, which connects the original flue gas heat exchanger and the net flue gas heat exchanger through the steam chamber, and uses a vacuum pump.
  • a vacuum pump To control the internal pressure of the heat exchanger to adjust the wall temperature, but since the original flue gas heat exchange tube and the net flue gas heat exchange tube are directly connected through the steam chamber, the circulation of the medium cannot be smoothly performed, and the wall temperature control is performed by the vacuum pump.
  • the pressure sensor is not accurate, which causes the control system to work effectively, resulting in unstable operation of the entire system. Summary of the invention
  • an object of the present invention is to provide a natural circulation indirect flue gas reheater capable of heating desulfurized net flue gas on the basis of avoiding acid dew corrosion and not affecting desulfurization efficiency. Without the addition of a power device, the above problems existing in the prior art are overcome.
  • the present invention provides a natural circulation indirect flue gas reheater comprising a heat absorption section disposed in a flue and a first heat release section, and a heating condensate placed outside the flue.
  • a second heat release section and a control system the heat absorption section is placed in a high temperature flue in front of the desulfurization tower, the first heat release section is placed in the low temperature flue behind the desulfurization tower, the first exothermic section, and the second The heat release section is respectively connected to the heat absorption section through a circulation pipe, wherein the circulation pipe is provided with a heat transfer medium; and a flow regulating valve is disposed on the condensed water pipe entering the second heat release section, the first heat release section A temperature sensor is disposed on the heat absorption section, and the flow regulating valve and the temperature sensor are connected to the control system.
  • the heat transfer medium is deoxidized water.
  • the second heat release section, the first heat release section and the heat absorption section are arranged one above the other in the vertical direction.
  • the high temperature flue and the low temperature flue are arranged in parallel in a horizontal direction.
  • the wall surface temperature of the heat absorption section is 20 ° C or more below the acid dew point temperature.
  • the natural circulation indirect flue gas reheater of the present invention has the following beneficial effects: it uses the heat of the flue gas before desulfurization to indirectly heat the flue gas after desulfurization, which is different from the direct desulfurization of the conventional GGH. Flue gas and flue gas heat exchange after desulfurization to heat the flue gas after desulfurization, solve the problems of corrosion and leakage of the original GGH system, and change the instability of the traditional GGH system. At the same time, the waste heat of the flue gas is further recovered, the temperature of the flue gas of the desulfurization tower is lowered, and the effect of energy saving and water saving of the desulfurization system is realized.
  • the heat transfer medium in the indirect flue gas reheater naturally circulates, and the indirect heat exchange of high-temperature flue gas and low-temperature flue gas can be realized without adding power equipment, and the control system is reasonable and effective;
  • the control system of the present invention combines the signal provided by the temperature sensor to control the flow of condensed water entering the second heat release section, thereby controlling the wall temperature of the heat absorption section and the net flue gas temperature of the outlet of the first heat release section, not only to achieve control
  • the purpose of wall temperature and smoke temperature is also to effectively recycle excess heat.
  • Figure 1 shows a schematic diagram of the traditional GGH process.
  • Figure 2 shows a schematic of a rotary heat exchanger.
  • Figure 3 shows a schematic diagram of the natural circulation indirect flue gas reheater of the present invention.
  • FIG. 4 is a schematic flow chart showing an embodiment of the natural circulation indirect flue gas reheater of the present invention. Component label description
  • the present invention provides a natural circulation indirect flue gas reheater comprising a heat absorption section 6 and a first heat release section 7 disposed in the flue, and a heating condensate outside the flue.
  • the second heat release section 8 and the control system 12 the heat absorption section 6 is placed in the high temperature flue 2 in front of the desulfurization tower 1, and the first heat release section 7 is placed in the low temperature flue 3 behind the desulfurization tower 1, first
  • the heat release section 7 and the second heat release section 8 are respectively connected to the heat absorption section 6 through the circulation pipes 9, 10, and the heat transfer medium is arranged in the circulation pipe; the flow is provided on the condensed water pipe 13 entering the second heat release section 8.
  • the regulating valve 11, the first heat releasing section 7 and the heat absorbing section 6 are respectively provided with a temperature sensor 14, and the flow regulating valve 11 and the temperature sensor 14 are connected to the control system 12.
  • the invention utilizes the waste heat of the flue gas before desulfurization to indirectly heat the net flue gas after desulfurization, prevents the smoke temperature after desulfurization from being too low, and generates problems such as smoke and rain and white smoke, and effectively reduces the inlet flue temperature of the desulfurization tower, thereby obtaining energy saving of the desulfurization tower.
  • the condensed water pipe may be a condensed water conveying pipe in the boiler make-up water system. Therefore, the above control system 12 achieves the purpose of controlling the wall temperature and the smoke temperature by adjusting the heat release amount of the second heat releasing section 8, and the second heat releasing section 8 During the control process, part of the heat is also absorbed. This part of the heat is used to heat the condensate and raise the boiler. The temperature of the make-up water allows the heat to be used effectively.
  • the high-temperature flue 2 in front of the desulfurization tower 1 and the low-temperature flue 3 behind the desulfurization tower are arranged in parallel in the horizontal direction, so that the The second heat release section 8, the first heat release section 7 and the heat absorption section 6 are arranged one above the other in the vertical direction.
  • This vertical direction arrangement better satisfies the circulation of the heat transfer medium under its own weight.
  • the heat transfer medium is deoxygenated water.
  • the above-mentioned circulation pipes 9, 10 are constituted by a riser pipe and a down pipe which are connected to the heat absorption section 6 and the first heat release section 7 and the second heat release section 8.
  • the invention Compared with the traditional GGH technology, the invention has three technical advantages. First, the invention focuses on recovering the flue gas residual heat before desulfurization to indirectly heat the desulfurized net flue gas, avoiding leakage and corrosion occurring in the conventional GGH technology. Second, through further research on low temperature acid dew corrosion, the wall temperature of the indirect flue gas reheater is allowed to be lowered to a lower temperature than the flue gas dew point temperature. Further, if traditional GGH technology is used The temperature of the desulfurization tower is generally maintained above the acid dew point temperature.
  • the wall temperature of the rear end indirect flue gas reheater is strictly controlled to 20 ° C below the acid dew point, that is, generally stated In the "first safe zone", it means that at least another low temperature waste heat corresponding to the temperature drop of the flue gas of 20 ° C can be utilized; third, the invention enters the desulfurization tower after indirect flue gas heat exchange The flue gas temperature is further reduced, so that the desulfurization system has the effect of saving energy and water.
  • the flue gas with higher temperature discharged from the precipitator enters the endothermic section 6 of the indirect flue gas reheater through the high temperature flue 2, and after releasing some heat through the endothermic section 6, it enters the desulfurization tower 1, in the desulfurization tower 1 After the reaction is carried out, it enters the first heat release section 7 through the low temperature flue 3, is heated by the first heat release section 7, and then enters the chimney 5 and is discharged from the chimney 5.
  • the indirect heat exchange of the indirect flue gas reheater directly exchanges heat with the GGH rotary heat exchanger.
  • the indirect heat exchange has no leakage characteristics, and the wall temperature of the indirect flue gas reheater of the present invention can be kept constant, and the wall surface temperature and the flue gas temperature have only a small gradient temperature drop, and the indirect flue gas reheats.
  • the wall temperature of the endothermic section of the device is above 20 °C (first safety zone) below the acid dew point temperature, the exhaust gas temperature is only about 15 °C higher than the wall temperature of the indirect flue gas reheater endothermic section.
  • the wall temperature can be kept constant when the net flue gas flow after desulfurization passes through the exothermic section of the indirect flue gas heat exchanger.
  • the flue gas releases heat to the heat transfer medium in the heat absorption section when passing through the heat absorption section 6.
  • the heat transfer medium is generally deoxidized water, and the heat transfer medium absorbs heat and the lift generated by the density difference passes through the circulation pipes 9, 10
  • the riser tube enters the first heat release section 7 and the second heat release section 8, and releases heat in the first heat release section 7 and the second heat release section 8 and then returns to the suction through the downcomers in the circulation pipes 9, 10.
  • the hot section 6, thus completing a cycle requires no external power throughout the cycle, and the circulation of the heat transfer medium is a natural cycle.
  • the net flue gas from the desulfurization tower is heated by the heat transfer medium, and then enters the chimney to be smoothly discharged, and the temperature sensor 14 is disposed on the first heat release section 7 and the heat absorption section 6, and the temperature is set.
  • the sensor transmits a signal to the control system 12, and when the temperature is lower than the set value, the control system 12 controls the opening degree of the flow regulating valve 11, reduces the opening degree thereof, and reduces the amount of condensed water entering the second heat releasing section 8,
  • the wall temperature of the first heat release section 7 and the heat absorption section 6 is raised, and the control system 11 keeps the wall surface temperature at a reasonable value so that the wall surface temperature of the heat absorption section is 20 ° C or more below the acid dew point temperature, thereby ensuring the wall surface. No serious corrosion will occur.
  • the natural circulation indirect flue gas reheater of the present invention can be used alone or in parallel.
  • the natural circulation indirect flue gas reheater of the present invention uses the residual heat of the flue gas before desulfurization to indirectly heat the net flue gas after desulfurization, preventing the flue temperature from being too low after desulfurization to generate smoke and rain and white smoke.
  • the heat absorption section and the heat release section of the invention are directly connected by the circulation pipe, and the heat transfer medium in the circulation pipe automatically flows without adding power
  • the control system adjusts the heat release of the second heat release section to adjust the heat absorption of the heat absorption section to ensure that the equipment avoids acid dew corrosion, and the application of the control system more precisely controls the smoking temperature, not only to control the wall temperature and the smoke temperature
  • the purpose is also to effectively recycle excess heat. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

Abstract

提供了一种自然循环间接式烟气再热器，其包括置于烟道内的吸热段和第一放热段、置于烟道外加热冷凝水的第二放热段以及控制系统，吸热段置于脱硫塔前方的高温烟道中，第一放热段置于脱硫塔后方的低温烟道中，第一放热段、第二放热段分别通过循环管与吸热段相连，循环管内设有传热介质；在进入第二放热段的冷凝水管道上设有流量调节阀，第一放热段和吸热段上均设有温度传感器，流量调节阀、温度传感器均与控制系统相连。采用回收脱硫前烟气的热量来间接加热脱硫后净烟气，解决了原有GGH系统得腐蚀、泄露等问题，改变了传统GGH系统的不稳定性。

Description

自然循环间接式烟气再热器 技术领域
本发明涉及湿法脱硫后净烟气再加热领域，特别是涉及一种自然循环间接式烟 气再热器。 背景技术
锅炉的烟气中含有二氧化硫， 直接排放会形成酸雨， 造成严重的环境污染； 尤 其是火电厂的二氧化硫治理工作已引起了广泛关注,国内电厂现都已采用有效装置 进行二氧化硫治理工作。 国内目前应用最多的脱硫方式是烟气湿法脱硫， 特别是石 灰石 (或石灰) -石膏湿法脱硫。 石灰石 (或石灰) -石膏湿法脱硫是以石灰石 (或石灰)作 吸收剂洗涤烟气中的二氧化硫生成亚硫酸钙，再与加入的空气进行氧化反应最后生 成石膏， 脱除二氧化硫， 净化烟气。 整个反应过程均在脱硫吸收塔内完成， 反应温 度一般为 50°C左右。
在石灰石 (或石灰) -石膏湿法脱硫系统中常设气-气换热器 (简称 GGH), 气 -气换 热器的具体作用： 一是吸收进入脱硫塔的烟气热量， 降低进入脱硫塔的烟气温度， 优化脱硫塔的运行工况； 二是利用吸收的烟气热量来加热脱硫吸收塔后方的净烟 气， 提高排烟温度 (一般要求不低于 80°C)， 减轻烟道和烟肉的低温湿烟气的腐蚀， 同时使烟囱出口的烟气有足够的抬升高度， 从而改善周围大气的环境质量。
目前市场上应用的 GGH装置流程如图 1所示， 进脱硫塔 1前的烟气与脱硫塔 后的净烟气通过回转式换热器 4直接换热， 吸热的净烟气进入烟囱 5， 高温烟道 2 与低温烟道 3 (净烟气烟道） 是垂直平行布置。 在传统 GGH运行过程中， 由于回 转式换热器结构的局限性， 其密封性能不好， 在运行过程中易发生泄漏造成二氧化 硫逃逸， 使得脱硫效率降低， 甚至排放不达标， 回转式换热器结构见图 2。 另一方 面， 如前述的烟气中含有二氧化硫， 它与烟气中的水蒸汽在烟气温度低于某一温度 时会形成硫酸， 会腐蚀设备， 因此无论是脱硫吸收塔上游侧的降温换热器还是下游 侧的加热器， 都存在酸露腐蚀的问题。 并且安装 GGH后， 由于 GGH部件的腐蚀 和换热元件的堵塞会降低湿法脱硫系统的可用率， 增加 GGH的维修费用。 因此， 一些湿法脱硫系统选择不安装 GGH， 直接湿烟肉运行， 但就会产生烟雨下洗和白 烟问题。 日本的低温电除尘技术也在一定程度上解决了脱硫后湿烟囱的问题，其系统有 "热回收器 +电除尘器 +再加热器"三部分组成， 热回收器 (MGGH-H/E)布置在空气预 热器之后和电除尘器的入口端之间， 再加热器 (MGGH-R/E)布置在湿法脱硫后与烟 囱之间的烟道上， 该技术的工作原理是采用热媒体（一般为水介质）与烟气通过热 回收器、 再加热器进行热交换， 使进入电除尘器的运行温度由通常的低温状态 ( 130〜140°C )下降到低低温状态（90〜100°C )， 并使脱硫后的烟温由通常的 50°C 提升到 90°C左右， 从而达到烟气余热利用降低能耗、 提高除尘与脱硫效率、 节省 脱硫用水、缓解电除尘下游设备腐蚀等问题。但该技术中热媒介在系统中运行需要 热泵来传送， 需要消耗大量能量来辅助系统运行， 造成运行成本有较大提高。
中国专利 ZL200610169891.9公开一种蒸发冷却烟气加热器， 其也为一种替代 传统 GGH的换热器， 其将原烟气换热器和净烟气换热器通过汽室相连， 运用真空 泵来控制换热器内部压力以调节壁温，但是由于原烟气换热管和净烟气换热管直接 通过汽室连接， 介质的循环并不能顺利进行， 而且通过真空泵来进行壁温控制， 在 实际实施过程中会遇到压力传感器测压不准而导致控制系统不能有效工作，导致整 个系统运行不稳定。 发明内容
鉴于以上所述现有技术的缺点，本发明的目的在于提供一种自然循环间接式烟 气再热器， 其可在避免酸露腐蚀以及不影响脱硫效率的基础上加热脱硫后的净烟 气， 且不用添加动力设备， 克服现有技术中存在的上述问题。
为实现上述目的及其他相关目的， 本发明提供一种自然循环间接式烟气再热 器， 其包括置于烟道内的吸热段和第一放热段、置于烟道外加热冷凝水的第二放热 段以及控制系统， 所述吸热段置于脱硫塔前方的高温烟道中， 所述第一放热段置于 脱硫塔后方的低温烟道中， 所述第一放热段、第二放热段分别通过循环管与吸热段 相连， 所述循环管内设有传热介质； 在进入所述第二放热段的冷凝水管道上设有流 量调节阀， 所述第一放热段和吸热段上均设有温度传感器， 所述流量调节阀、温度 传感器均与控制系统相连。
优选的， 所述传热介质为除氧水。
优选的，所述第二放热段、第一放热段和吸热段按竖直方向依次上下排列设置。 优选的， 所述高温烟道和低温烟道按水平方向平行设置。 优选的， 所述吸热段的壁面温度在酸露点温度以下 20°C以上。
如上所述， 本发明的自然循环间接式烟气再热器， 具有以下有益效果： 其采用 回收脱硫前烟气的热量来间接加热脱硫后净烟气， 其不同于传统 GGH的直接用脱 硫前烟气和脱硫后净烟气换热的方式来加热脱硫后净烟气， 解决了原有 GGH系统 的腐蚀、 泄漏等问题， 改变了传统 GGH系统的不稳定性。 同时又更进一步深度地 回收了烟气的余热， 降低脱硫塔进口烟温， 实现脱硫系统节能节水的效果。 也不同 于日本的低温电除尘技术， 本间接式烟气再热器中传热介质自然循环， 无需添加动 力设备即可实现高温烟气和低温烟气的间接换热， 并且控制系统合理有效； 本发明 中的控制系统结合温度传感器提供的信号来控制进入第二放热段的冷凝水流量，以 此来控制吸热段的壁温和第一放热段的出口净烟气温度，不仅达到控制壁温和烟温 的目的， 也将多余的热量进行了有效的回收利用。 附图说明
图 1显示为传统 GGH流程示意图。
图 2显示为回转式换热器示意图。
图 3显示为本发明的自然循环间接式烟气再热器示意图。
图 4显示为本发明的自然循环间接式烟气再热器实施例流程示意图。 元件标号说明
1 脱硫塔
2 高温烟道
3 低温烟道
4 回转式换热器
5 烟囱
6 吸热段
7 第一放热段
8 第二放热段
9、 10 循环管
11 流量调节阀
12 控制系统 13 冷凝水管道
14 温度传感器 具体实施方式
以下由特定的具体实施例说明本发明的实施方式，熟悉此技术的人士可由本说 明书所揭露的内容轻易地了解本发明的其他优点及功效。
请参阅图 1至图 4。 须知， 本说明书所附图式所绘示的结构、 比例、 大小等， 均仅用以配合说明书所揭示的内容， 以供熟悉此技术的人士了解与阅读， 并非用以 限定本发明可实施的限定条件， 故不具技术上的实质意义， 任何结构的修饰、 比例 关系的改变或大小的调整， 在不影响本发明所能产生的功效及所能达成的目的下， 均应仍落在本发明所揭示的技术内容得能涵盖的范围内。 同时， 本说明书中所引用 的如"上"、 "下"、 "左"、 "右"、 "中间 "及"一"等的用语， 亦仅为便于叙述的明了， 而非用以限定本发明可实施的范围， 其相对关系的改变或调整， 在无实质变更技术 内容下， 当亦视为本发明可实施的范畴。
如图 3及图 4所示， 本发明提供一种自然循环间接式烟气再热器， 其包括置于 烟道内的吸热段 6和第一放热段 7、 置于烟道外加热冷凝水的第二放热段 8以及控 制系统 12， 吸热段 6置于脱硫塔 1前方的高温烟道 2中， 第一放热段 7置于脱硫 塔 1后方的低温烟道 3中， 第一放热段 7、 第二放热段 8分别通过循环管 9、 10与 吸热段 6相连， 循环管内设有传热介质； 在进入第二放热段 8的冷凝水管道 13上 设有流量调节阀 11， 第一放热段 7和吸热段 6上均设有温度传感器 14， 流量调节 阀 11、 温度传感器 14均与控制系统 12相连。 本发明利用脱硫前烟气的余热来间 接加热脱硫后的净烟气， 防止脱硫后烟温过低而生成烟雨下洗和白烟等问题， 同时 有效降低脱硫塔进口烟温， 得到脱硫塔节能节水的效果； 同时本发明的吸热段和放 热段通过循环管直接相连， 循环管内的传热介质自动流动， 无需添加动力设备； 并 且通过控制系统调节第二放热段的放热量来调节吸热段的吸热量，确保设备避免酸 露腐蚀，控制系统的应用更精确地控制吸烟温度，不仅达到控制壁温和烟温的目的， 也将多余的热量进行了有效的回收利用。
上述冷凝水管道可以是锅炉补给水系统中的冷凝水输送管道， 因此， 上述控制 系统 12通过调节第二放热段 8的放热量来达到控制壁温和烟温的目的， 第二放热 段 8在控制过程中同时也吸收了部分热量， 这部分热量用来加热冷凝水， 提高锅炉 补给水的温度， 使得热量得以有效利用。
为更好的实现传热介质在循环管内完成自循环， 见图 4所示， 上述脱硫塔 1前 方的高温烟道 2和脱硫塔后方的低温烟道 3按水平方向平行设置，这样可以满足将 上述第二放热段 8、 第一放热段 7和吸热段 6按竖直方向依次上下排列设置， 这种 竖直方向的设置更好地满足传热介质在自重下完成循环。优选的， 上述传热介质为 除氧水。
上述循环管 9、 10由连接吸热段 6和第一放热段 7、 第二放热段 8的上升管和 下降管构成。
本发明与传统 GGH技术相比， 有三个技术优势， 第一， 本发明着眼于回收脱 硫前烟气余热来间接地加热脱硫后的净烟气， 避免了传统 GGH技术中所出现的泄 漏， 腐蚀等问题； 第二， 通过对低温酸露腐蚀的进一步研究， 本间接式烟气再热器 壁面温度允许降低至一个比烟气酸露点温度更低的温度水平， 进一步说， 如果采用 传统 GGH技术， 脱硫塔烟温一般维系在酸露点温度以上， 但是， 如果使用本发明 提供的技术， 将后端间接式烟气再热器的壁面温度严格控制在酸露点以下 20°C， 即通常所述的 "第一安全区 "内，它意味着至少又有与烟气 20°C温降相对应的低温余 热能够为人们所利用； 第三， 本发明经间接式烟气换热后进入脱硫塔的烟气温度进 一步降低， 使得脱硫系统得到了节能节水的效果。
本发明自然循环间接式烟气再热器的工作原理如下：
从除尘器排出的具有较高温度的烟气，通过高温烟道 2进入间接式烟气再热器 的吸热段 6， 经过吸热段 6释放部分热量后进入脱硫塔 1， 在脱硫塔 1内进行反应 后通过低温烟道 3进入第一放热段 7， 经过第一放热段 7被加热后进入烟囱 5， 从 烟囱 5排出。
在烟气依次被引至间接式烟气再热器的吸热段 6和第一放热段 7时，间接式烟 气再热器的间接换热与 GGH的回转式换热器直接换热相比， 间接式换热具有无泄 漏特性， 且本发明的间接式烟气再热器的壁面温度可保持恒定， 且壁面温度和烟气 温度只有较小梯度温降， 间接式烟气再热器的吸热段壁面温度在酸露点温度以下 20°C以上 （第一安全区） 时， 排烟温度仅比间接式烟气再热器吸热段的壁温高出 15°C左右， 与此同时， 脱硫后的净烟气流经间接式烟气换热器的放热段时， 壁面温 度亦能保证恒定。 烟气在经过吸热段 6时将热量释放给吸热段中的传热介质，传热介质一般为除 氧水， 传热介质吸收热量后因密度差产生的升力通过循环管 9、 10中的上升管进入 第一放热段 7和第二放热段 8中，在第一放热段 7和第二放热段 8中释放热量后通 过循环管 9、 10中的下降管回到吸热段 6， 由此完成一个循环， 在整个循环过程中 无需外部动力， 传热介质的循环为自然循环。 在第一放热段 7中， 从脱硫塔出来的 净烟气被传热介质加热， 然后进入烟囱顺利排出， 在第一放热段 7和吸热段 6上均 设有温度传感器 14， 温度传感器将信号传递给控制系统 12， 在温度低于设定值时， 控制系统 12控制流量调节阀 11的开度， 将其开度减小， 使进入第二放热段 8的冷 凝水量减少， 使第一放热段 7和吸热段 6的壁温上升， 控制系统 11使壁面温度始 终保持在一个合理值， 使吸热段的壁面温度在酸露点温度以下 20°C以上， 从而保 证壁面不会发生严重腐蚀现象。
本发明的自然循环间接式烟气再热器， 可单独使用， 也可以并联使用。
综上所述， 本发明的自然循环间接式烟气再热器， 利用脱硫前烟气的余热来间 接加热脱硫后的净烟气， 防止脱硫后烟温过低而生成烟雨下洗和白烟等问题， 同时 有效降低脱硫塔进口烟温， 得到脱硫塔节能节水的效果； 同时本发明的吸热段和放 热段通过循环管直接相连， 循环管内的传热介质自动流动， 无需添加动力设备； 并 且通过控制系统调节第二放热段的放热量来调节吸热段的吸热量，确保设备避免酸 露腐蚀，控制系统的应用更精确地控制吸烟温度，不仅达到控制壁温和烟温的目的， 也将多余的热量进行了有效的回收利用。所以， 本发明有效克服了现有技术中的种 种缺点而具高度产业利用价值。
上述实施例仅例示性说明本发明的原理及其功效， 而非用于限制本发明。任何 熟悉此技术的人士皆可在不违背本发明的精神及范畴下，对上述实施例进行修饰或 改变。 因此， 举凡所属技术领域中具有通常知识者在未脱离本发明所揭示的精神与 技术思想下所完成的一切等效修饰或改变， 仍应由本发明的权利要求所涵盖。

Claims

权利要求书 、 一种自然循环间接式烟气再热器，其特征在于，包括置于烟道内的吸热段（6) 和第一放热段（7)、 置于烟道外加热冷凝水的第二放热段（8) 以及控制系统
( 12)， 所述吸热段（6)置于脱硫塔前方的高温烟道（2) 中， 所述第一放热 段 （7) 置于脱硫塔后方的低温烟道 （3) 中， 所述第一放热段 （7)、 第二放 热段 （8) 分别通过循环管 （9、 10) 与吸热段 （6) 相连， 所述循环管 （9、 10) 内设有传热介质； 在进入所述第二放热段的冷凝水管道 （13 ) 上设有流 量调节阀（ 11 )，所述第一放热段（7)和吸热段（6)上均设有温度传感器（14)， 所述流量调节阀 （11 )、 温度传感器 （14) 均与控制系统 （12) 相连。 、 根据权利要求 1所述的自然循环间接式烟气再热器， 其特征在于： 所述传热 介质为除氧水。 、 根据权利要求 1所述的自然循环间接式烟气再热器， 其特征在于： 所述第二 放热段（8)、 第一放热段（7)和吸热段（6)按竖直方向依次上下排列设置。 、 根据权利要求 1所述的自然循环间接式烟气再热器， 其特征在于： 所述高温 烟道 （2) 和低温烟道 （3) 按水平方向平行设置。 、 根据权利要求 1所述的自然循环间接式烟气再热器， 其特征在于： 所述吸热 段 （6) 的壁面温度在酸露点温度以下 20°C以上。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108786365A (zh) * 2018-08-03 2018-11-13 周裕 烟囱白汽处理装置及方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9657943B2 (en) 2014-12-16 2017-05-23 Great River Energy Method and system for reheating flue gas using waste heat to maintain dry chimney stack operation
CN114870582A (zh) * 2022-06-06 2022-08-09 连云港虹洋热电有限公司 一种垃圾焚烧发电用蒸汽锅炉尾气脱硫系统

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4705101A (en) * 1979-10-04 1987-11-10 Heat Exchanger Industries, Inc. Flue gas reheat apparatus
CN1045168A (zh) * 1989-01-24 1990-09-05 阿尔斯特罗姆公司 循环流化床锅炉中再热蒸汽温度控制系统和方法
CN1995823A (zh) * 2006-12-30 2007-07-11 中国科学院电工研究所 蒸发冷却烟气加热器
CN202274502U (zh) * 2011-09-30 2012-06-13 上海伏波环保设备有限公司 利用锅炉机组抽汽来加热脱硫后净烟气的系统

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS521734A (en) * 1975-06-24 1977-01-07 Sasakura Eng Co Ltd Heat recovering method
CH617983A5 (en) * 1977-04-01 1980-06-30 Sulzer Ag Open gas turbine system which is combined with a steam circuit
US4649034A (en) * 1985-06-14 1987-03-10 Conoco Inc. Catalyzed flue gas desulfurization
US5282429A (en) * 1989-08-09 1994-02-01 Chubu Electric Power Company Inc. Method and system for handling exhaust gas in a boiler
US5509461A (en) * 1993-12-02 1996-04-23 The Babcock & Wilcox Company Gas-gas heater protection system and method
JP2000161647A (ja) * 1998-12-01 2000-06-16 Babcock Hitachi Kk 排ガス処理装置とガス再加熱器
JP3776641B2 (ja) * 1999-09-29 2006-05-17 バブコック日立株式会社 ガスガス熱交換装置
JP5350996B2 (ja) * 2009-11-25 2013-11-27 バブコック日立株式会社 酸素燃焼システムの排ガス処理装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4705101A (en) * 1979-10-04 1987-11-10 Heat Exchanger Industries, Inc. Flue gas reheat apparatus
CN1045168A (zh) * 1989-01-24 1990-09-05 阿尔斯特罗姆公司 循环流化床锅炉中再热蒸汽温度控制系统和方法
CN1995823A (zh) * 2006-12-30 2007-07-11 中国科学院电工研究所 蒸发冷却烟气加热器
CN202274502U (zh) * 2011-09-30 2012-06-13 上海伏波环保设备有限公司 利用锅炉机组抽汽来加热脱硫后净烟气的系统

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108786365A (zh) * 2018-08-03 2018-11-13 周裕 烟囱白汽处理装置及方法

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