【正文】 22 AP001)。In the PLC program the outgoing signal to control valve (00QHM01AA003 for boiler 10 and 00QHM02AA003 for boiler 20) is minimized to 5 % to ensure the minimum water flow.在PLC程序中，向控制閥(鍋爐10的為00QHM01AA003，鍋爐20的為00QHM02AA003) 發(fā)出的信號最小值為5%，以保證最低流量。For deaerating (venting) during startup sequence the boiler, there is a valve on the steam outlet (00QHF12 AA001 for boiler 10 and 00QHF22 AA001 for boiler 20), which opens when the boiler pressure is below the set open limit and closes when the pressure reaches the set close limit. The venting pipe connects with the safety valves blowoff pipe. During standby operation the valves are closed.在啟動順序中，鍋爐排廢氣：蒸汽出口處有一個閥門(00QHF12 AA001用于鍋爐10，00QHF22 AA001用于鍋爐20)，當(dāng)鍋爐壓力低于設(shè)定的開啟限值時閥門開啟，當(dāng)鍋爐壓力達到設(shè)定的關(guān)閉限值時閥門關(guān)閉。對“最低壓力”的控制就可避免這一連鎖反應(yīng)。排污罐內(nèi)的水位是恒定的。 Na3PO4:磷酸鈉：Cold start:冷啟動：At cold start of boilers, dosing of trisodium phosphate (Na3PO4) is done directly to the respective boiler by the dosing pump (00QCC10 AP001 for boiler 10 and 00QCC20AP001 for boiler 20) in order to increase conductivity and pH and to minimize the startup time. The valves (00QCC11/21 AA001) are manually operated to switch dosing from one boiler to another if one of the dosing pumps fail. 鍋爐冷啟動時，電解質(zhì)加藥泵(00QCC10 AP001用于鍋爐10，00QCC20AP001用于鍋爐20) 會直接向兩鍋爐內(nèi)添加Na3PO4溶液，以增加爐水電導(dǎo)率和PH值，并盡量減少設(shè)備啟動時間。The following samples can be extracted:需采樣的位置如下：Water from feed water tank (cooler 00QUB30KC001)除氧器給水（冷卻器00QUB30KC001）Water from boiler 10 (cooler 00QUB11KC001), from inner vessel鍋爐（10）爐水(冷卻器 00QUB11KC001)， 內(nèi)筒取樣。Before each of the actuators, there are shutoff ball valves, which links the stainless steel pipes with plastic pipes connected to the actuators.制動器前有兩個截流球閥，一頭連接著不銹鋼管，另一頭連接著塑料管（塑料管與制動器連接）。這兩個水泵水平安裝在底座上，各按100%流量設(shè)計。 Circulation pumps循環(huán)泵There are two circulation pumps (00QHM11/12 AP001 and 00QHM21/22 AP001) for each boiler, horizontally mounted on a base plate, each designed for 100% of the flow.One pump is in operation, while the other is standby. 兩個鍋爐上各有兩個循環(huán)泵(00QHM11/12 AP001 和 00QHM21/22 AP001)，水平安裝在底座上，各按流量的100%設(shè)計。 Makeup water pumps補水泵There are two makeup water pumps (00QHC11AP001 and 00QHC12AP001) for this system, each designed for 100% of the flow.本系統(tǒng)配有兩個補水泵(00QHC11AP001 和 00QHC12AP001)。Normally both boilers are chosen for operation, which mean that they work in parallel. Serial operation is not possible, although a sequential operation can be achieved by setting the pressure set points for the respective boiler with some difference.正常情況下，兩臺鍋爐是獨立工作，也就是說，它們是協(xié)同工作的，相互之間不發(fā)生干擾，即使是通過設(shè)定兩臺鍋爐各自不同的壓力設(shè)定點以達到協(xié)同工作的目的也是不允許的。停止和運行可通過設(shè)定控制板上的電站運行開關(guān)（0或1）來選擇。See section for more details.。See section for more details. 。The function of the pumps is to pump feed water from the feed water tank to the respective boiler, as described above. 給水泵的作用是分別把給水從給水泵里泵入各自的鍋爐內(nèi)，如上所述。The spraytype deaerator releases the dissolved gases in the ining water by reducing it to a fine spray. The counter current flow of steam from the feed water tank heats the water to near the steam saturation temperature and removes nearly all traces of oxygen. In the feed water tank a steam cushion prevents it from recontamination with oxygen.除氧器通過把水通過噴嘴霧化的方式出去其中的溶解氣體。? Compressed / Instrument Air System (QHP)壓縮空氣/儀表空氣系統(tǒng)Compressed air (instrument air) is used for operation of the pneumatic actuators: 氣動裝置運行需要使用儀用壓縮空氣。A level switch (00QCC10/20CL101) stops the dosing pumps at low level.加藥泵低液位時，液位開關(guān)關(guān)閉加藥泵。 Dosing System (QCC, QCF) 加藥系統(tǒng)(QCC, QCF) N2H4:聯(lián)氨：Hydrazine (N2H4) is added to the feed water tank by a dosing pump (00QCF10 AP001) fitted on the hydrazine dosing tank (00QCF10 BB001). The purpose of this is to maintain a hydrazine excess in the feed water tank. Dosing is done manually and the hydrazine excess is checked manually thru sample cooler for feed water tank. 安裝在化學(xué)加藥罐(00QCF10 BB001)上的加藥泵(00QCF10 AP001)負責(zé)將聯(lián)氨投放到除氧器內(nèi)，以維持濕保護時除氧器內(nèi)過量聯(lián)氨。流量變送器(00QHF40 CF001)向PLC發(fā)送與蒸汽流量對應(yīng)的420mA信號。各閥設(shè)計流量均大于最大排放量的50%。For removing precipitated solids(sludge),the blow down valve (00QHE01 AA001/AA002 for boiler 10 and 00QHE11 AA001/AA002 for boiler 20), will open manually and blow water from the bottom of the boiler to the blow down tank.當(dāng)排除鍋爐內(nèi)的沉淀物(污泥)時，手動開啟排污閥(鍋爐10的為00QHE01 AA001/AA002，鍋爐20的為 00QHE11 AA001/AA002)后，爐水會從鍋爐底部被排到排污罐里。The forced circulation system ensures a fast startup and shutdown. The constant mixing of water also eliminates the risk for a salt concentration at the surface, which otherwise would occur.強制循環(huán)系統(tǒng)可保證鍋爐快速調(diào)整功率。As long as the load does not exceed the power set point (max. allowed powered), it is the boilers’ steam pressure that is controlled. 只要載荷不超過功率設(shè)定點（允許的最大功率）就可控制鍋爐的蒸汽壓力。每個三相電極(三相電極00QHA10 AH101供鍋爐10所用 ，00QHA20 AH101供鍋爐20所用)包含若干個安在單電極盤上的金屬電極棒，并被固定在內(nèi)筒上方。During standby operation the feed water pump fills the boiler between two water volume set points.設(shè)備運行期間，給水泵的給水量處于兩個水量設(shè)定值之間。The steam is lead to the bottom of the tank and passed through spreader pipes which create a circulation and thus a good mixing in the tank. 除氧蒸汽通過除氧器內(nèi)擴散器管道從除氧器底部進入除氧器，這樣有利于蒸汽與水的充分混合。During standby or if the boiler pressure is below a set value the feed water control valve (00QHG11/12 AA006) is closed before a pump is started and the opening of the valve is reduced to a set value to remove the risk for cavitations in the pump due to high flow.在設(shè)備備用期間或當(dāng)鍋爐壓力低于設(shè)定值時，開啟另一個泵之前，給水控制閥(00QHG11/12 AA006)將關(guān)閉，同時閥門的開度會調(diào)整到一個設(shè)定值，以避免給水泵帶來的汽蝕危險。The feed water tank’s pressure, and indirect its temperature, is maintained by regulating the control valve (00QHF30 AA004) for the steam from the boilers to the feed water tank.通過調(diào)節(jié)鍋爐供給除氧器蒸汽的調(diào)節(jié)閥，可保持除氧器的壓力及對應(yīng)的溫度。這些工作將由安裝在鍋爐和除氧器內(nèi)的380V低壓電氣元件（備用加熱器）完成。?2General Description of the System系統(tǒng)一般說明 System系統(tǒng)說明? water System (QHG)鍋爐給水系統(tǒng)（QHG系統(tǒng)）Makeup water, demineralized water (QHC) is fed to the feed water tank (00QHJ10 BB010) by makeup water pumps to