201243262 六、發明說明： 【發明所屬之技術領域】 本發明涉及鍋爐煙氣餘熱吸收利用方面，特別涉及一種 用鋼爐煙氣餘熱加熱導熱油的系統。 【先前技術】 有機熱載體爐20世紀30年代始於美國，由美國道生化學 公司首創，習慣稱為道生爐，並逐步形成系列。其採用有 機熱載體作為傳輸熱能的中間載體，將燃料燃燒產生的熱 能藉由加熱爐受熱面將熱能傳遞給有機熱載體，使熱載體 被加熱至-定的溫度，然後用循環油泉將其送入用轨設 備’釋放熱能後之低溫有機熱載體再相加熱爐中重新被 加熱’如此往復循環，即可㈣有機熱載體加熱爐向外界 供熱之㈣。其有如下幾個其他種類鍋爐所無法取代之特 點：1、可在較低工作壓力下獲得較高溫度之熱介質；2、 液相循環供熱，無冷凝排放熱損失，供熱系統熱效率高； 3、由於運作控制方便、傳熱均句，戶斤以能滿足用熱系統 精確之處理溫度要求。因此在石&、化工、紡織、印染、 橡膠、製革、食品、木材加工等許多行業中得到了日益廣 泛之應用。同時正如前述之優點—可在較低之工作塵力下 獲得較高溫度之熱介質那樣，此等熱介質之溫度一般為 200°C至300°C，有的甚至更高。 … 鋼爐排放之煙氣中含有酸性氣體，煙溫高時其會以氣態 形式流經鋼爐各受熱面直至到脫硫塔襄被除去。當煙溫低 於某-溫度時，其會與煙氣中之水蒸汽結合成硫酸而= J62312.doc 201243262 換熱設備。低溫腐蝕通常出現在空氣預熱器之冷端以及給 水溫度低之省煤器令。當受熱面之溫度低於煙氣之露點 時，煙氣中之水蒸汽及煤燃燒後所生成之三氧化硫（僅為 硫燃料產物之很少一部分）結合成之硫酸會凝結在受熱面 上，嚴重腐蝕受熱面《為避免鍋爐尾部受熱面之酸露腐 蚀，通常鍋爐排煙溫度設計得較高，新鍋爐M(rc左右， 運作一段時間後往往會高達16〇t:，此部分煙氣之直接排 放造成了很大的能源浪費。 由於前文所述之鍋爐之排煙溫度通常在l4(rc至l6〇t>c左 右，而技術背景第一段提及之熱介質之溫度一般為2〇〇〇c 至300°C，直接的熱交換換熱技術不可能自14〇c>c至16(rc 之煙氣換熱給200°C至300°C之導熱油。因此要想回收此部 分低溫熱量來加熱處理所需之200«>c至3〇〇t導熱油，必須 重新佈置鍋爐之尾部受熱面。 【發明内容】 本發明所要解決之問題係提供一種用鍋爐煙氣餘熱加熱 導熱油之系統’克服現有技術中之上述問題。 本發明之用鍋爐煙氣餘熱加熱導熱油之系統包括按煙氣 流經方向設在煙道内之省煤器及空氣預熱器，亦包括導熱 油加熱器’設在所述煙道内省煤器之前方，所述導熱油加 熱器藉由循環管與用熱設備相連，循環管上設有循環泵。 本發明進一步包括煙氣餘熱回收利用裝置，所述煙氣餘 熱回收利用裝置包括藉由循環管道相連之吸熱段及放熱 段’吸熱段置於所述煙道内空氣預熱器之後方，放熱段置 162312.doc 201243262 於所述省煤器之進水管道上或置於所述空氣預熱 通道内。 器之進風 本發明所述煙氣餘熱回收利用裝置之工作介質常為高溫 強制循環水或自然循環蒸汽， 側， ’因此其傳熱係數遠高於煙氣201243262 VI. Description of the Invention: [Technical Field] The present invention relates to a waste heat absorption and utilization of boiler flue gas, and more particularly to a system for heating a heat transfer oil using residual heat of a steel furnace flue gas. [Prior Art] The organic heat carrier furnace started in the United States in the 1930s and was first created by the American Daosheng Chemical Company. It is used to be called the Daosheng Furnace and gradually formed a series. The organic heat carrier is used as an intermediate carrier for transmitting heat energy, and the heat energy generated by the combustion of the fuel transfers heat energy to the organic heat carrier through the heating surface of the heating furnace, so that the heat carrier is heated to a predetermined temperature, and then the oil is heated by a circulating oil spring. After being fed into the rail equipment, the low-temperature organic heat carrier after releasing the heat energy is reheated in the reheating furnace, so that (4) the organic heat carrier heating furnace supplies heat to the outside (4). It has the following characteristics that cannot be replaced by other types of boilers: 1. It can obtain higher temperature heat medium at lower working pressure; 2. Liquid phase circulating heat supply, no condensation heat loss, and high heat efficiency of heating system 3, due to the convenience of operation control, heat transfer, the household can meet the precise temperature requirements of the thermal system. Therefore, it has been widely used in many industries such as stone & chemical, textile, printing and dyeing, rubber, leather, food, wood processing. At the same time, as with the aforementioned advantages, the heat medium can be obtained at a lower working dust level, and the temperature of the heat medium is generally 200 ° C to 300 ° C, and some even higher. ... The flue gas discharged from the steel furnace contains acid gas. When the temperature of the flue gas is high, it will flow through the heated surfaces of the steel furnace until it reaches the desulfurization tower. When the temperature of the smoke is lower than a certain temperature, it will combine with the water vapor in the flue gas to form sulfuric acid = J62312.doc 201243262 heat exchange equipment. Low temperature corrosion typically occurs at the cold end of the air preheater and the economizer order where the feed water temperature is low. When the temperature of the heated surface is lower than the dew point of the flue gas, the water vapor in the flue gas and the sulfur trioxide formed by the combustion of the coal (only a small part of the sulfur fuel product) are combined to form a sulfuric acid which will condense on the heating surface. Severe corrosion heating surface "In order to avoid acid dew corrosion of the heating surface of the boiler tail, the boiler exhaust gas temperature is usually designed to be higher. The new boiler M (about rc, after operation for a period of time, often up to 16 〇t:, this part of the flue gas The direct discharge causes a great waste of energy. Since the exhaust temperature of the boiler described above is usually around l4 (rc to l6〇t > c), the temperature of the heat medium mentioned in the first paragraph of the technical background is generally 2 〇〇〇c to 300 °C, direct heat exchange heat transfer technology is not possible from 14〇c>c to 16 (rc heat exchange to 200 ° C to 300 ° C heat transfer oil. So to recycle this Part of the low-temperature heat to heat the 200«>c to 3〇〇t heat-conducting oil required for heat treatment, the rear heating surface of the boiler must be rearranged. SUMMARY OF THE INVENTION The problem to be solved by the present invention is to provide a waste heat of boiler flue gas. Heat transfer oil system 'overcoming the prior art The above problem. The system for heating the heat transfer oil with the waste heat of the boiler flue gas comprises the economizer and the air preheater disposed in the flue according to the direction of the flue gas flow, and the heat transfer oil heater is disposed in the flue. In front of the economizer, the heat transfer oil heater is connected to the heat device by a circulation pipe, and the circulation pipe is provided with a circulation pump. The invention further includes a flue gas waste heat recovery and utilization device, and the flue gas waste heat recovery device includes The heat absorbing section and the heat absorbing section connected by the circulation pipe are placed behind the air preheater in the flue, and the heat release section is disposed on the water inlet pipe of the economizer or placed on the water inlet pipe of the economizer. In the air preheating passage, the working medium of the flue gas waste heat recovery and utilization device of the present invention is often high temperature forced circulation water or natural circulation steam, side, so the heat transfer coefficient is much higher than that of the flue gas.
裝置可隨鍋爐負荷之變動隨意調節壁溫，使其始終高於煙 氣酸露點溫度，使設備免受酸露腐蝕之前提下最大程度地 回收排煙餘熱。 本發明當所述放熱段置於所述省煤器之進水管道上時， 所述省煤器之進水管道上進一步設有除氧器及高壓加熱 器’鍋爐給水依次流經所述放熱段、除氧器、高壓加熱器 後再流入所述省煤器。 本發明所述除氧器及高壓加熱器間相連之水管上設有給 水泵。 本發明所述高壓加熱器之進汽管與所述除氧器之進汽管 相連通’高壓加熱器之凝結水疏水管與除氧器相連接。 本發明進一步包括控制系統、兩個溫度感測器及多個流 量調節閥，所述溫度感測器及流量調節閥分別與控制系統 相連，其中一個溫度感測器設於所述吸熱段上，另一個溫 度感測器設於所述省煤器及空氣預熱器間之煙道上或者所 述省煤器之出水管上，其中一路鍋爐給水經第一流量調節 閥流入除氧器，另一路鍋爐給水經第二流量調節閥及放熱 段流入除氧器，第三流量調節閥設在所述高壓加熱器之進 汽管上。 162312.doc 201243262 本發明當所述放熱段置於所述空氣預熱器之進風通道内 時’進一步包括控制系統、溫度感測器及流量調節風門， 所述溫度感測器及流量調節風門分別與控制系統相連，所 述溫度感測器設於所述吸熱段上，流量調節風門設在所述 空氣預熱器之進風通道内’且按進風方向置於放熱段之前 方。 本發明進一步包括油氣分離器，設在所述導熱油加熱器 與用熱設備間之循環管上。 本發明所述油氣分離器進一步與一膨脹槽相連，所述膨 脹槽與注油泵相連。 藉由以上技術方案，本發明之用鋼爐煙氣餘熱加熱導熱 油之系統，充分利用煙氣餘熱，藉由改變鍋爐尾部受熱面 佈置順序，在保證原鍋爐效率與出力之同時，降低鍋爐排 煙溫度，回收鋼爐煙氣部分餘熱，並用其回收之熱量加熱 熱載體一導熱油，可應用於石油、化工、紡織、印染、橡 膠、製革、食品、木材加工等許多行業。且在保證煙氣流 經之所有設備免受酸露腐蝕之前提下，最大程度地回收煙 氣餘熱，提昇了能源之可利用品質，提高了鍋爐排煙品 質，使熱能利用形式多樣化。 【實施方式】 本發明之用鍋爐煙氣餘熱加熱導熱油的系統包括按煙氣 流經方向設在煙道内之省煤器及空氣預熱器，亦包括設在 煙道内省煤器前方之導熱油加熱器，導熱油加熱器藉由循 環管與用熱設備相連’循環管上設有循環系。 162312.doc 201243262 如圖1所示，煙道丨内按煙氣流經方向依次設置：導熱油 力=器2、省煤器3及空氣預熱器4,導熱油加熱器2藉由'循 %官道與用熱設備19相連，且在循環管道上設有循環泵12 來驅動熱載體於導熱油加熱器中之循環。鍋爐尾部煙道【 中之煙氣將部分熱量傳給導熱油加熱器2中之熱載體（熱載 體包括（但不限於）導熱油’以下同）’熱載體由循環果⑵區 動，在用熱設備19中放出熱量，且循環重複加熱、放熱之 此過程。用熱設備19可以應用於石油、化工、紡織、印 染、橡膠、製革、食品、木材加工等許多行業巾。本發明 將導熱油加熱器2置於省煤器3前方，吸收進入省煤器之煙 氣餘熱，此處煙氣溫度高、熱量高，因此，可充分利用鍋 爐煙道内之煙氣餘熱。 導熱油加熱器2與用熱設備19之間的循環管道上進一步 設有油氣分離器18，油氣分離器18之一個進油管與膨脹槽 之出油管相連，膨脹槽17之進油管與注油㈣相連膨 脹槽17亦與-儲油槽15相連。儲油槽此仙為設備停運 檢修時儲存導熱油；注料16之作用為注人新油、排放舊 油；膨脹槽17為導熱油加熱後受熱膨脹緩衝之用；油氣分 離器18之作用為分離導熱油中可能混有之水分，改良導熱 油傳熱效果。 由於導熱油加熱器之置人會導致進人省煤器及其後方空 氣預熱器之煙溫變低’可能會影響省煤器、空氣預熱器等 設備之使用。因此’本發明之—個較佳實施例在空氣預熱 器4後方加設-個煙氣餘熱回收利用裝置，所述煙氣餘熱 1623I2.doc 201243262 回收利用裝置可回收部分煙氣餘熱回饋給省煤器或空氣預 熱器’對省煤器或空氣預熱器之熱量進行補償。 在其中一個更優之實施例中，煙氣餘熱回收利用裝置包 括藉由循環管道相連之吸熱段5及放熱段6，吸熱段5置於 空氣預熱器後方之煙道内，吸收部分煙氣餘熱，煙氣餘熱 回收裝置之放熱段6置於省煤器3之進水管道上。煙氣流過 吸熱段5後進入脫硫除塵設備進行處理。 本實施例中，省煤器3之進水管道上亦設有除氧器14、 給水泵7及高壓加熱器u，鍋爐給水分兩路進入除氧器 14，其中一路經由第一流量調節閥21直接流入除氧器μ， 另一路經由第二流量調節閥9流經煙氣餘熱回收利用裝置 之放熱段6吸熱後再流入除氧器14 ;鍋爐給水自除氧器14 流出經過給水泵7後流入高壓加熱器丨丨，經高壓加熱器1 i 加熱後再進入省煤器3。且高壓加熱器丨丨之進汽管與除氧 器14之進汽管相連通，且在高壓加熱器丨丨之進汽管上設有 第三流量調節閥13，高壓加熱器丨丨之凝結水疏水管與除氧 器14相連。高壓加熱器及除氧器共用一個熱汽源，熱汽源 部分汽體直接進入除氧器14，部分汽體藉由高壓加熱器j j 加熱锅爐給水’散熱後之氣體變成冷凝水經由高壓加熱器 11與除氧器14之間的凝結水疏水管流入除氧器丨4。 本發明系統進—步包括控制系統、兩個溫度感測器8、 10及多個流量調節閥9、n、21，所述溫度感測器及流量 調節閥分別與控制系統相連；溫度感測器8位於煙氣餘熱 回收利用裝置吸熱段5上量測設備之壁面溫度，溫度感測 162312.doc 201243262 器10位於省煤器3與空氣預熱器4之間的煙道中或省煤器之 出水官上，藉由調節流量調節閥9及流量調節閥2丨，在保 證進入除氧器14水量不變之條件下，調節進入放熱段6内 之水量來控制所需熱量，藉此避免煙氣餘熱回收利用裝置 吸熱段5爻酸露腐蝕，最大程度地回收排煙餘熱。 導熱油加熱器2吸收煙道内煙氣餘熱來加熱導熱油，具 體之吸熱量根據煙氣之酸露點溫度計算來決定；假設原鍋 爐系統空氣預熱器4之出口排煙溫度為Tl，酸露點溫度為 I，為保證煙氣餘熱回收利用裝置吸熱段5不受酸露腐 蝕’此時吸熱段5與煙氣接觸之壁面溫度應比丁2高，留 10°c之安全裕量，同時煙氣之溫度與吸熱段5之壁面溫度 應留有一疋之傳熱溫差，才能保證煙氣餘熱回收利用裝置 爻熱面之佈置經濟合理，因此此時之煙氣餘熱回收利用裝 置排煙溫度為T2+10°c之安全裕量+約i 5 之傳熱溫差，記 為丁3，可計异出原鋼爐系統之節能溫降空間為丁1_丁3，由於 煙氣餘熱回收利用裝置用來間接補償省煤器3之換熱損 失，並沒有對外提供熱量，因此真正回收之節能量為導熱 油加熱器2之對外供熱，顯然導熱油加熱器2之進出口煙氣 溫降不能大於TrT3，如此才能保證原鍋爐熱力系統儘可 能地不受加裝本發明設備之影響。 導熱/由加熱器2之進出口油溫溫差一般設計為3 〇，以 此選擇合適之導熱油循環流量來將吸收之熱量傳遞給用熱 設備19 ;導熱油加熱器2吸收煙氣部分熱量造成省煤器3、 空氣預熱器4吸收量之減少’吾人在省煤器3之進水管上安 162312.doc 201243262 裝一個高壓加熱器1 l ’藉由熱力計算，調整鍋爐給水溫 度，使得省煤器3出口煙溫及水溫與原系統接近或略高於 原系統，此使得省煤器3、空氣預熱器4不受接入導熱油加 熱器之影響。 接入高壓加熱器11之熱源用汽為去除氧器14之抽汽，此 部分抽汽源為用於加熱進除氧器14之鍋爐給水；現用來做 高壓加熱器11熱源’因此若要保證總抽汽熱量不變，必須 尋找一加熱進除氧器14補給水之替代熱源。鍋爐之排煙溫 度為140°C至160°C，加熱之補給水溫度通常為2(Tc，若煙 氣直接與銷爐補給水換熱’則換熱器壁面溫度接近煙氣酸 露點溫度’可能造成換熱設備之酸露腐蝕，本實施例藉由 煙氣餘熱回收裝置解決此問題。吸熱段5置於煙道中吸收 熱量傳遞給工作介質，工作介質再在放熱段6傳遞給2〇。〇 之鍋爐補給水，工作介質工作機制通常為高溫強制循環水 或自然循環蒸汽，因此其傳熱係數遠高於煙氣側，使得壁 面溫度由工作介質侧溫度決定，因此，可藉由控制工作介 負之溫度來控制吸熱段5免受酸露腐蝕。 如圖2所示，本發明用鍋爐煙氣餘熱加熱導熱油的系統 之另一實施例，其中與上述實施例區別在於：煙氣餘熱回 收利用裝置之放熱段6置於空氣預熱器4之進風通道内，煙 氣餘熱回收利用裝置主要用來加熱空氣預熱器之進風風 皿在本實把例中，省煤器之進水管上可設有低壓加熱器 或其他。本實施例之控制系統與一個溫度感測器8及一個 抓量調郎門20相連，溫度感；則器8設在吸熱段上測試壁 162312.doc 201243262 面溫度，流量調節風門2〇設在空氣預熱器4之進風通道 内，並按進風方向置於放熱段6之前方，以此調節吸熱段 之吸熱量。本實施例煙氣餘熱回收裝置吸收之熱量僅加熱 進入空*1預熱器之送風，補償空氣預熱器換熱量之減少。 【圖式簡單說明】 圖1為本發明之用鍋爐煙氣餘熱加熱導熱油之系統之一 具體實施例的示意圖。 圖2為本發明之用鍋爐煙氣餘熱加熱導熱油之系統之另 一實施例的示意圖。 【主要元件符號說明】 1 煙道 2 導熱油加熱器 3 省煤器 4 空氣預熱器 5 吸熱段 6 放熱段 7 給水泵 8 溫度感測器 9 第二流量調節閥 10 溫度感測器 11 高虔加熱器 12 循環泵 13 第三流量調節閥 14 除氧器 1623I2.doc • 11 - 201243262 15 儲油槽 16 注油果 17 膨脹槽 18 油氣分離器 19 用熱設備 20 流量調節風門 21 第一流量調節閥 162312.doc -12-The device can adjust the wall temperature arbitrarily with the change of boiler load, so that it is always higher than the temperature of the flue gas dew point, so that the equipment can be recovered to the maximum extent of waste heat before the acid dew corrosion. In the present invention, when the heat release section is placed on the water inlet pipe of the economizer, the water inlet pipe of the economizer is further provided with a deaerator and a high pressure heater, and the boiler feed water sequentially flows through the heat release. The section, the deaerator, and the high pressure heater then flow into the economizer. A water pump is arranged on the water pipe connected between the deaerator and the high pressure heater of the present invention. The inlet pipe of the high pressure heater of the present invention is in communication with the inlet pipe of the deaerator. The condensate drain pipe of the high pressure heater is connected to the deaerator. The invention further includes a control system, two temperature sensors and a plurality of flow regulating valves, wherein the temperature sensor and the flow regulating valve are respectively connected to the control system, wherein a temperature sensor is disposed on the heat absorption section, Another temperature sensor is disposed on the flue between the economizer and the air preheater or on the outlet pipe of the economizer, wherein one of the boiler feed water flows into the deaerator through the first flow regulating valve, and the other path The boiler feed water flows into the deaerator through the second flow regulating valve and the heat release section, and the third flow regulating valve is disposed on the steam inlet pipe of the high pressure heater. 162312.doc 201243262 The invention further includes a control system, a temperature sensor and a flow regulating damper when the heat releasing section is placed in the air inlet passage of the air preheater, the temperature sensor and the flow regulating damper Connected to the control system respectively, the temperature sensor is disposed on the heat absorption section, and the flow regulating damper is disposed in the air inlet passage of the air preheater and placed in front of the heat release section in the air inlet direction. The invention further includes an oil and gas separator disposed on the circulation pipe between the heat transfer oil heater and the heat device. The oil and gas separator of the present invention is further connected to an expansion tank which is connected to the oil pump. According to the above technical solution, the system for heating the heat-conducting oil by using the residual heat of the steel furnace flue gas of the invention fully utilizes the waste heat of the flue gas, and reduces the boiler row by ensuring the efficiency and output of the original boiler while changing the order of the heating surface of the boiler tail. The temperature of the smoke recovers part of the residual heat of the flue gas of the steel furnace, and heats the heat carrier and the heat transfer oil with the heat recovered therefrom, and can be applied to many industries such as petroleum, chemical, textile, printing and dyeing, rubber, leather, food, wood processing and the like. And to ensure that all the equipment of the flue gas flow is protected from acid dew corrosion, the waste heat of the flue gas is recovered to the greatest extent, the energy quality of the energy is improved, the quality of the boiler exhaust is improved, and the form of heat utilization is diversified. [Embodiment] The system for heating heat transfer oil by using boiler flue gas waste heat includes the economizer and air preheater disposed in the flue according to the direction of the flue gas flow, and the heat transfer oil disposed in front of the economizer in the flue. The heater and the heat transfer oil heater are connected to the heat device by a circulation pipe. The circulation pipe is provided with a circulation system. 162312.doc 201243262 As shown in Figure 1, the flue gas is arranged in the direction according to the direction of the flue gas flow: heat transfer oil = 2, economizer 3 and air preheater 4, heat transfer oil heater 2 by '% by cycle The official road is connected to the heat device 19, and a circulation pump 12 is provided on the circulation pipe to drive the circulation of the heat carrier in the heat transfer oil heater. Boiler tail flue [the flue gas in the boiler transfers part of the heat to the heat carrier in the heat transfer oil heater 2 (the heat carrier includes (but is not limited to) the heat transfer oil 'below the same)) The heat carrier is moved by the circulating fruit (2), in use The heat is released from the heat device 19, and the process of heating and exothermic is repeated in a cycle. The thermal equipment 19 can be applied to many industrial towels such as petroleum, chemical, textile, printing, rubber, leather, food, wood processing, and the like. The heat exchanger oil heater 2 is placed in front of the economizer 3 to absorb the residual heat of the flue gas entering the economizer, where the flue gas temperature is high and the heat is high, so that the residual heat of the flue gas in the flue of the boiler can be fully utilized. An oil and gas separator 18 is further disposed on the circulation pipe between the heat transfer oil heater 2 and the heat utilization device 19. One of the oil inlet pipes 18 is connected to the oil discharge pipe of the expansion tank, and the oil inlet pipe of the expansion tank 17 is connected to the oil injection pipe (four). The expansion tank 17 is also connected to the oil reservoir 15. The oil storage tank stores the heat transfer oil when the equipment is shut down for maintenance; the effect of the injection 16 is to inject new oil and discharge the old oil; the expansion tank 17 is used for heating expansion buffer after the heat transfer oil is heated; the function of the oil separator 18 is Separating the moisture that may be mixed in the heat transfer oil improves the heat transfer effect of the heat transfer oil. Due to the placement of the heat transfer oil heater, the temperature of the smoke entering the economizer and the air preheater behind it may become low, which may affect the use of economizers, air preheaters and the like. Therefore, a preferred embodiment of the present invention adds a flue gas waste heat recovery device behind the air preheater 4, and the flue gas waste heat 1623I2.doc 201243262 recycling device can recover part of the flue gas waste heat feedback to the province. The coal or air preheater 'compensates for the heat of the economizer or air preheater. In a preferred embodiment, the flue gas waste heat recovery device comprises a heat absorption section 5 and a heat release section 6 connected by a circulation pipe, and the heat absorption section 5 is placed in the flue gas behind the air preheater to absorb part of the flue gas waste heat. The exothermic section 6 of the flue gas waste heat recovery device is placed on the water inlet pipe of the economizer 3. After the smoke flows through the heat absorption section 5, it enters the desulfurization and dust removal equipment for processing. In this embodiment, the water removal pipe of the economizer 3 is also provided with a deaerator 14, a feed water pump 7 and a high pressure heater u, and the boiler feeds two water into the deaerator 14, one of which passes through the first flow regulating valve. 21 directly flows into the deaerator μ, and the other path flows through the second flow regulating valve 9 through the exothermic section 6 of the flue gas waste heat recovery device and then flows into the deaerator 14; the boiler feed water flows out of the deaerator 14 through the feed pump 7 After flowing into the high pressure heater, it is heated by the high pressure heater 1 i and then enters the economizer 3. The inlet pipe of the high-pressure heater is connected to the inlet pipe of the deaerator 14, and the third flow regulating valve 13 is arranged on the inlet pipe of the high-pressure heater, and the high-pressure heater is condensed. The water drain pipe is connected to the deaerator 14. The high-pressure heater and the deaerator share a hot steam source, and part of the steam source directly enters the deaerator 14 , and some of the vapors heat the boiler feed water by the high-pressure heater jj. The heat-dissipated gas becomes condensed water and is heated by high pressure. The condensate drain pipe between the device 11 and the deaerator 14 flows into the deaerator 丨4. The system further comprises a control system, two temperature sensors 8, 10 and a plurality of flow regulating valves 9, n, 21, wherein the temperature sensor and the flow regulating valve are respectively connected to the control system; temperature sensing The device 8 is located at the wall surface temperature of the measuring device on the heat absorption section 5 of the flue gas waste heat recovery and utilization device, and the temperature sensing 162312.doc 201243262 10 is located in the flue between the economizer 3 and the air preheater 4 or the economizer In the water discharge official, by adjusting the flow regulating valve 9 and the flow regulating valve 2丨, the amount of water entering the heat releasing section 6 is adjusted to control the required amount of heat while ensuring the amount of water entering the deaerator 14 to thereby control the required heat, thereby avoiding the smoke. The waste heat recovery unit of the gas waste heat recovery unit is corroded by the bismuth acid dew, and the waste heat of the exhaust gas is recovered to the utmost extent. The heat transfer oil heater 2 absorbs the waste heat of the flue gas in the flue to heat the heat transfer oil, and the specific heat absorption is determined according to the acid dew point temperature calculation of the flue gas; assuming that the exhaust temperature of the outlet of the original boiler system air preheater 4 is Tl, the acid dew point The temperature is I, in order to ensure that the endothermic section of the flue gas waste heat recovery and utilization device is not corroded by acid dew. At this time, the wall surface temperature of the endothermic section 5 in contact with the flue gas should be higher than that of Ding 2, leaving a safety margin of 10 ° C, while the smoke The temperature of the gas and the wall surface temperature of the heat absorption section 5 should have a heat transfer temperature difference to ensure that the arrangement of the hot surface of the flue gas waste heat recovery device is economical and reasonable. Therefore, the exhaust gas temperature of the flue gas waste heat recovery and utilization device at this time is T2. The safety margin of +10 °c + the heat transfer temperature difference of about i 5 is recorded as D3, and the energy-saving temperature drop space of the original steel furnace system can be counted as D-1, which is used for the flue gas waste heat recovery and utilization device. Indirectly compensated for the heat loss of the economizer 3, and no external heat is supplied. Therefore, the energy consumption of the real recovery is the external heat supply of the heat transfer oil heater 2. It is obvious that the temperature of the inlet and outlet of the heat transfer oil heater 2 cannot be greater than TrT3. In order to protect Original boiler thermodynamic system as possible to not affect the installation of the apparatus of the present invention. Heat conduction / the temperature difference between the inlet and outlet of the heater 2 is generally designed to be 3 〇, so as to select a suitable heat transfer oil circulation flow to transfer the absorbed heat to the heat device 19; the heat transfer oil heater 2 absorbs part of the heat of the smoke Economizer 3, air preheater 4 reduction of the amount of absorption 'Our people in the economizer 3 inlet pipe 162312.doc 201243262 installed a high-pressure heater 1 l 'by thermal calculation, adjust the boiler feed water temperature, so that the province The flue gas temperature and water temperature at the exit of the coal 3 are close to or slightly higher than the original system, which makes the economizer 3 and the air preheater 4 unaffected by the heat transfer oil heater. The heat source steam connected to the high-pressure heater 11 is the steam extraction of the oxygen removal device 14. The part of the steam extraction source is the boiler feed water for heating into the deaerator 14; now used to make the high-pressure heater 11 heat source' The total extraction steam heat is constant, and an alternative heat source for heating the deaerator 14 feed water must be sought. The exhaust temperature of the boiler is 140 ° C to 160 ° C, and the temperature of the heated make-up water is usually 2 (Tc, if the flue gas directly exchanges heat with the feed water of the pin furnace), the wall temperature of the heat exchanger is close to the temperature of the flue gas dew point. This problem may be caused by the acid dew corrosion of the heat exchange equipment. In this embodiment, the problem is solved by the flue gas waste heat recovery device. The heat absorption section 5 is placed in the flue to absorb heat and transferred to the working medium, and the working medium is transferred to the heat release section 6 to the crucible. Boiler feed water, the working medium working mechanism is usually high temperature forced circulation water or natural circulation steam, so its heat transfer coefficient is much higher than the flue gas side, so that the wall temperature is determined by the temperature of the working medium side, so it can be controlled by the work. Dividing the temperature to control the heat absorption section 5 from acid dew corrosion. As shown in Fig. 2, another embodiment of the system for heating the heat transfer oil with boiler flue gas waste heat, wherein the difference from the above embodiment is: flue gas waste heat The exothermic section 6 of the recycling device is placed in the air inlet passage of the air preheater 4, and the flue gas waste heat recovery and utilization device is mainly used to heat the air preheater of the air preheater in the present example, saving coal The inlet pipe of the device may be provided with a low-pressure heater or the like. The control system of the embodiment is connected with a temperature sensor 8 and a grasping and adjusting door 20, and the temperature is sensed; then the device 8 is set on the heat-absorbing section to test the wall. 162312.doc 201243262 The surface temperature and flow regulating damper 2 is disposed in the air inlet passage of the air preheater 4, and is placed in front of the heat release section 6 in the air inlet direction to adjust the heat absorption amount of the heat absorption section. The heat absorbed by the flue gas waste heat recovery device only heats the air supplied into the air preheater to compensate for the decrease of the heat exchange amount of the air preheater. [Fig. 1] The heat transfer oil for the waste heat of the boiler flue gas of the present invention is used. BRIEF DESCRIPTION OF THE DRAWINGS Figure 2 is a schematic view of another embodiment of a system for heating a heat transfer oil using boiler flue gas waste heat according to the present invention. [Main component symbol description] 1 Flue 2 heat transfer oil heater 3 provinces Coal 4 air preheater 5 heat absorption section 6 heat release section 7 feed water pump 8 temperature sensor 9 second flow regulating valve 10 temperature sensor 11 sorghum heater 12 circulation pump 13 third flow regulating valve 14 Is 1623I2.doc • 11 - 201243262 15 17 oil reservoir 16 expander 18 oiling fruit oil separator tank 19 with the flow regulating device 20 heat flow damper 21 of the first adjusting valve 162312.doc -12-