鍋爐水循環(huán)和水處理外文翻譯

1、<p><b>　　中文3822字</b></p><p>　　附錄 專業(yè)外文資料翻譯</p><p><b>　　一.英文資料</b></p><p>　　Boiler Circulation＆Water Treatment</p><p>　　An adequate fl

2、ow of water and water-steam mixture is necessary for steam generation and control of tube metal temperatures in all the circuits of a steam-generating unit. At supercritical pressures, this flow is produced mechanically

3、by means of pumps. At subcritical pressures, circulation is produced either naturally by the action of the force of gravity, by pumps, or by a combination of the two.</p><p>　　Fig-1 Simple natural-circulat

4、ion circuit (diagrammatic) </p><p>　　including primary steam separator in drum</p><p>　　The force of gravity available to produce flow in natural circulation comes from the difference between th

5、e densities (1b/cuft) of the fluids in the downcomer (downflow) and riser (upflow) portions of the circuit (Fig-1). Maximum pumping effect occurs if the fluid in the downcomers is water at or slightly below saturation te

6、mperature and free of steam bubbles. Heat-absorbing rises at saturation temperature convey to the boiler drum a water-steam mixture of less density than that of the water in </p><p>　　The flow in the various

7、 circuits of boiler units designed for forced circulation at subcritical pressures, is produced by mechanical pumps. There are two general types of forced-circulation systems, a “once-through ” system and a “recirculatin

8、g” system.</p><p>　　The “once-through” force-circulation type receives water from the feed supply, pumping it to the inlet of the heat-absorbing circuits. Fluid heating and steam generation take place along

9、the length of the circuit until evaporation is complete. Further progress through the heated circuits results in superheating the vapor. Conventionally this type of force circulation requires no steam-and-water drum. A m

10、odification of the “once-through” type evaporates to partial dryness(90%quality) removeing th</p><p>　　The “recirculation” forced-circulation-type unit has water supplied to the heat-absorbing circuits throu

11、gh a separate circulating pump. The water pumped is considerably in excess of the steam produced and, like a natural-circulation boiler, a steam-and-water drum is required for steam separation. The separated water togeth

12、er with feedwater from the feed pump is returned through downcomer circuits to the circulating pump for another “round trip.”</p><p>　　In the recirculating type of forced circulation there is a net thermal l

13、oss for the boil unit because of the separate circulating pump. While practically all the energy required to drive the pumps reappears in the water as added enthalpy, this energy originally came from the fuel at a conver

14、sion-to-useful-energy factor of less than 1.0. If an electric motor drive is used, the net energy lost, referred to the fuel input in a plant with 33%thermal efficiency, is about twice the energy supplied to </p>

15、<p>　　Natural circulation</p><p>　　In a natural-circulation system, circulation increases with increased heat input (and increased steam output) until a point of maximum fluid flow is reached. Beyond th

16、is point, any further increase in heat absorption results in a flow decrease. The from of the curve, shown in Fig-2, is produced by two opposing forces, An increase in downcomers and risers as the heat absorption increas

17、es. At the same time, the friction and other flow losses in both downcomers and risers also increase. When the ra</p><p>　　When design conditions are limited to the rising portion of the circulation curve, a

18、 natural-circulation boiler tends to be self-compensating for the numerous variations in heat-absorption conditions encountered in an operating unit. These include sudden overloads, change in heat-absorbing-surface clean

19、liness, nonuniform fuel bed or burner conditions,and even the inability to forecast precisely actual conditions over the operating lifetime.</p><p>　　Fig-2 typical relationship between circulation in a bo

20、iler circuit (at a given pressure) and amount of steam steam produced(scale arbitraiy)</p><p>　　No similar compensating effect is inherent in a forced-circulation unit operating at subcritical pressures, sin

21、ce a large part of the total resistance of the riser circuits, much greater than the natural circulation effect, is caused by flow-distribution devices required at the circuit inlets. Under these conditions, because of t

22、he disproportionately large resistance of the distributors, an increase in heat absorption to an individual circuit or group of circuits causes only a slight change in t</p><p>　　The method of producing flow

23、 in boiler circuits, whether natural or mechanical, has virtually no bearing on the effectiveness of heat-absorbing surfaces as long as the inside surface is werred at all times by the water in a water-steam mixture of s

24、uitable quality to maintain nucleate boiling. Provided this fundamental requirement is met, the water-film resistance to heat flow is negligibly small, and the overall heat conductance depends on gas-side and tube-wall r

25、esistances. Within the nucleate </p><p>　　With either type of circulation, any departure from the nucleate boiling regime requires special consideration of the forced-convection stearn-film heat transfer coe

26、fficient and its relation to permissible metal temperatures.</p><p>　　Forced or natural circulation</p><p>　　Under certain conditions forced circulation can be usefully applied to steam generati

27、on. Mechanical means to move the fluid within the circuits are employed for boilers designed to operate above or near the critical pressure (3208.2psia.) There are instances, also, in the process and waste-heat fields wh

28、ere temperature control or consolidating heat pickup from widely separated points can be economically effected by the use of pumps. The condition where forced circulation can be applied to advant</p><p>　　Na

29、tural circulation is most effectively emploved when large changes in density usually restricted to subcritical pressure designs where thereis a considerable difference in density between steam and water. At pressures abo

30、ve 2900 psi a natural-circulation system becomes increasingly large and costly,and a pump may be more economical to assure positive flow.</p><p>　　The forced-circulation principle, however, is equally operab

31、le in both the supercritical and subcritical pressure ranges. The selection of the identifying name “Universal-Pressure” boiler reflects the broad applicability of the once-through forced-circulation principle. Its choic

32、e,as opposed to the retention of natural circulation in the subcritical range, is essentially determined by the economics of the installation.</p><p>　　Fig-3 Densities of steam and water at saturated steam

33、 temperature</p><p>　　for pressures from atmospheric to critical</p><p>　　The differential in densities of steam and water for the range of 14.7 to 3208.2 psia is noted in Fig-3. A substantial d

34、ifferential persists well up toward the critical pressure. As long as the maximum effectiveness off this differential is maintained by the efficient separation of the steam from the water in the circnlating system, as wi

35、th the use of cyclone steam separator, mechanical aid to circulation is not essential.</p><p>　　Internal Treatment of Water</p><p>　　There are numerous chemicals ,some called boiler compounds, o

36、n the market and recommended for “internal” water softening and other treatment. Their duty is to stabilize hardness agents, prevent scaling or residual make deposits easily removable. Such chemicals are also used for n

37、eutralization of residual hardness in systems after external treatment. Chemicals of this nature are introduced at a more or less constent rate in dissolved state into feed tanks or systems. The most frequently used che&

38、lt;/p><p>　　The most effective method of introducing internal treatment compounds to ensure a reasonable degree of quantity control is by means of dosage apparatus consisting of one or more containers having ma

39、nual or motor driven agitators and a dosage pump. </p><p>　　As a general rule internal treatment alone, for waters of much more than 5°（UK）（７０p.p.m）hardness is not recommended because system and make-up

40、 quantities and water composition may become critical and precipitated sludge and salts are liable to increase density of water and solidification of sludge with consequent propensity to foaming and priming in steam plan

41、t and circulation complications.</p><p>　　Internal treatment is generally used within limits for smallish systems, say up to 23MW or as residual treatment and to raise pH value to a requisite amount.</p&g

42、t;<p>　　External Treatment of Water</p><p>　　External softening of system and make-up water is the more effective and comprehensive method of water treatment for any size of plant and network and it c

43、an suit most water characteristics. Nowadays external treatment involves the principle of ion-exchange, which ensures water of virtually zero hardness.</p><p>　　The ion-exchange process can be described as f

44、ollows. Molecules of dissolved salts are dissociated in from of free electrically charged ions in liquid solution. In the forch field they tend to be attracted to opposite charges: positive cations to the negative cathod

45、es and negative anions to the positive anode. Ion-exchange materials are insoluble artificial resins to which activated chemical groups with tied dissociable ions, are attached. Ion exchangers are classified in accordanc

46、e with dissoci</p><p>　　Base exchange water treatment </p><p>　　In the base exchange process, raw water containing calcium and magnesium salts passes through a bed of cation synthetic resin acti

47、vated by sodium base. Calcium and magnesium salts are exchanged for quantitatively equivalent salts of sodium (sodiumbicarbonate) and soft water.</p><p>　　This neutral ion exchange does not change the salt c

48、ontent of free and tied carbonic acid remain constant. Water softened by the base exchange process is free of calcium and magnesium hardness agents. Sodium bicarbonate is dissolved in water and deposits are prevented. Th

49、ere is a tendency for dissociation of sodium bicarbonate at temperatures above 110℃ resulting in some part-tied and tied carbon dioxide being released as aggressive agent.</p><p>　　When the active exchange m

50、aterial ceases to be effective due to saturation by calcium and magnesium, its softening power is regenerated by flushing with solution of brine. The high concentration of sodium ions in the brine replaces calcium and ma

51、gnesium chlorides in the exchange material and reactivates it. Calciumn and magnesium chlorides are flushed out with brine to sewage.</p><p>　　There is no practical limit to regeneration and exchane material

52、 does not become exhausted. In the case of such mechanical impurities as iron content above 0.3mg/1 or manganese over 0.2mg/1 being introduced by raw water, the exchange material can become contaminated thus experiencing

53、 reduced capacity. If such impure waters are involved, introduction of a special pre-filter is good practice ; foreign bodies cannot be dislodged from the exchanger bed in the course of regeneration and frequent rene<

54、/p><p>　　The base exchange softener consists of a specially lined steel cylinder, half filled exchange material and provided with suitable connections. The plant can be fully automatic with frequency of regene

55、ration dictated by pre-determined quantity of water passing through or by presence of hardness indicated by test. Adjustment of water quantity is seldom required and chemicals other than salt are not necessary. Paralleli

56、ng of two interconnected units allows alternate regeneration and therefore cont</p><p>　　Ion-exchange demineralization</p><p>　　Feed water for modern high pressure plant must be of such quality

57、as to have all salts and dissolved silica acid neutralised. With generation of steam, salts should remain as sediment and condensate virtually becomes distilled water. </p><p>　　Much progress in development

58、of methods of water treatment is due to evolution of insoluble artificial resins for the process of ion-exchange in order to render water to a degree of purity required for modern plant. In the demineralization process w

59、ater is passed through such beds of granulated exchangers in series, to achieve purity of 5～20p.p.m.total dissolved solids.</p><p>　　In the cation exchanger, cations in water (calcium,magnesium,sodium and po

60、tassium) are exchanged for hydrogen ions, forming free acids from water dissolved salts. In the second series connected anion exchange container,the abovemention ed acid water loses the free acids leaving silica and carb

61、on dioxide. Water is then fully deminerelised.</p><p>　　Treatment offering full demineralisation is employed in most power stations and also for manufacturing processes requiring optimum purity of water. Com

62、plete demineralization of fill and make-up is not necessary for small and medium sized installations; fully treated water or condensate possibly available from associated or adjacent boiler plant and power stations, prov

63、es to be most satisfactory for district heating systems. </p><p><b>　　二.中文翻譯</b></p><p><b>　　鍋爐水循環(huán)和水處理</b></p><p>　　為了產(chǎn)生蒸汽和控制蒸汽發(fā)生設(shè)備中所有回路的管壁溫度，需要充足的水和汽水混合物。在超

64、臨界壓力下，流量是利用水泵機(jī)械地產(chǎn)生地。在低于臨界壓力時(shí)，水循環(huán)或者由重力作用自然地產(chǎn)生，或者由水泵來產(chǎn)生，或者既利用重力作用又利用水泵來產(chǎn)生。</p><p>　　圖－1 簡(jiǎn)單的自然循環(huán)回路示意圖（圖中示出汽包中的一次汽水分離器）</p><p>　　在自然循環(huán)中，可用產(chǎn)生流量地重力，即來自回路中地下降管（下流）中地流體密度（1h/ft³）與上升管（上流）中地流體密度之差（

65、圖－1）。如果下降管中地流體是飽和溫度的水，或是溫度稍低于飽和溫度的水，并且水中不含有氣泡時(shí)，則有最大的泵水效果。在飽和溫度下，吸收熱量的上升管將密度比下降管中的水密度小的汽水混合物送到汽包中去。這個(gè)密度之差便產(chǎn)生了水循環(huán)可以利用的力。</p><p>　　為了在亞臨界壓力下進(jìn)行強(qiáng)迫循環(huán)而設(shè)計(jì)的鍋爐設(shè)備，其各個(gè)回路的流量都是用機(jī)械泵產(chǎn)生的。強(qiáng)迫循環(huán)系統(tǒng)有兩種普遍采用的形式：直流系統(tǒng)和再循環(huán)系統(tǒng)。</p>

66、;<p>　　在直流式強(qiáng)迫循環(huán)中，將給水設(shè)備供采的水，泵到受熱面回路的進(jìn)口。流體沿著同路的長(zhǎng)度被加熱．并產(chǎn)生蒸汽，一直到蒸發(fā)過程完成，然后再流過加熱回路，使蒸汽過熱。按照習(xí)慣，這種形式的強(qiáng)迫循環(huán)不需要用汽水包。直流的一種改進(jìn)形式是將水蒸發(fā)到部分干度(90％的干度)，再在汽水分離器中除去多余的水。</p><p>　　再循環(huán)式強(qiáng)迫循環(huán)設(shè)備足用另外裝置的循環(huán)泵將水送到受熱面回路中去。由泵送進(jìn)回路的水量大

67、大超過產(chǎn)生蒸汽所用的水量，并且和自然循環(huán)鍋爐一樣，也需要有一個(gè)汽包作為汽水分離之用。分離出來的水與給水泵送來的水匯合后經(jīng)下降管回路回到循環(huán)泵中去，作另一次“來回旅行”。</p><p>　　在強(qiáng)迫循環(huán)的再循環(huán)形式中．由于這另外裝置的循環(huán)泵而造成了鍋爐設(shè)備的凈熱損失。實(shí)際上，雖然所有需用于驅(qū)動(dòng)泵的能量在水中以增加焓的形式再現(xiàn)，但是，這能量最初來自于轉(zhuǎn)換為有用功系數(shù)小于1.0的燃料。如果用電動(dòng)泵的話，按照一個(gè)熱效率為

68、33％的電廠所輸入燃科的熱量采計(jì)算，則其凈能量的損失約為供給水泵電動(dòng)機(jī)能量的兩倍。</p><p><b>　　自然循環(huán) </b></p><p>　　在自然循環(huán)系統(tǒng)中，循環(huán)量隨著所供給熱員的增加而增加(蒸汽出力也增加)，并一直增加到最大的循環(huán)流體流量點(diǎn)才停止。超過這一點(diǎn)，吸熱量的任何進(jìn)一步增長(zhǎng)，其結(jié)果都會(huì)使循環(huán)流量減少。在圖－2中所示的曲線形狀是由兩個(gè)相對(duì)的力形成

69、的。由于吸熱且的增加，下降管和上升管中的流體密度之差U及管內(nèi)的流速也隨之加大。與此同時(shí)，下降瞥和上升瞥中的摩擦損失和其他流動(dòng)損失也增加了。當(dāng)這些損失的增加牢大于由于密度之差所得的力，則循環(huán)流量率開始下降，這些損失的增加主要是由于上升回路中比窖的增加所造成的。因此，將所有的回路都設(shè)計(jì)在圖－2中曲線的上升部分才是適當(dāng)?shù)?，也即設(shè)計(jì)在曲線頂點(diǎn)的左側(cè)運(yùn)行。</p><p>　　圖－2 在既定壓力下，鍋爐回路中的循環(huán)量和

70、產(chǎn)生蒸</p><p>　　汽量的典型怪吸曲線（坐標(biāo)尺度示任意選擇的）</p><p>　　當(dāng)設(shè)汁條件限制在循環(huán)曲線的上升部分時(shí)，自然循環(huán)鍋爐對(duì)于運(yùn)行設(shè)備所遇到的各種吸熱條件的變化都有自身補(bǔ)償?shù)内厔?shì)。這些變化包括突然過負(fù)荷、受熱向表面清潔度的變化、不均勻的爐床或不均勻的噴燃器的條件，甚至在運(yùn)行壽命期間所不能正確預(yù)料的實(shí)際條件。</p><p>　　在亞臨界壓力下，運(yùn)

71、行中的強(qiáng)迫循環(huán)鍋爐不具備類似的補(bǔ)償作用，因?yàn)樯仙芈房傋枇χ械囊淮蟛糠质窃宦愤M(jìn)口處所需要的流量分配設(shè)施造成的，這個(gè)阻力比自然循環(huán)的組力大得多。在這種情況下，由于流量分配設(shè)施的不均衡阻力大．因此．個(gè)別回路內(nèi)或一組回路內(nèi)的吸熱量的增加，僅僅使流速率稍有變化。</p><p>　　在鍋爐回路中產(chǎn)生流動(dòng)的方法．無論是自然方法，或是機(jī)械方法，實(shí)際上，只要管子的內(nèi)表面始終被具有維持核態(tài)沸騰的合適于度的汽水混合物中的水所潤(rùn)濕．

72、就不會(huì)對(duì)受熱面的效率有所影響。只要符合于基本要求，水膜對(duì)熱流的阻人是小得可以忽略不計(jì)的。并且，總熱導(dǎo)取決于爐煙側(cè)的管壁的熱阻。在核態(tài)沸騰狀況下，不管循環(huán)流量是由自然方式產(chǎn)生的，還是由水泵產(chǎn)生的，鍋爐爐膛受熱面上或者鍋爐對(duì)流受熱面上每平方英尺所吸收的熱量基本上相等。無論采用兩種循環(huán)方式個(gè)的哪一種，任何偏離核態(tài)沸騰方式都要求對(duì)強(qiáng)迫對(duì)流蒸汽膜的熱傳導(dǎo)系數(shù)和它對(duì)金屬允許溫度的關(guān)系予以特別考慮。</p><p><b

73、>　　強(qiáng)迫循環(huán)或自然循環(huán)</b></p><p>　　在某些情況下，強(qiáng)迫循環(huán)用于產(chǎn)生蒸汽是有益的。為了在高于或近于臨界壓力(3208.2psia)下運(yùn)行而設(shè)計(jì)的銘爐可采用機(jī)械方式使流體在回路中流動(dòng)。在工藝過程和余熱利用領(lǐng)域內(nèi)也有這樣的情況：由分散的各點(diǎn)進(jìn)行溫度控制或匯集熱的采用都會(huì)由于泵的使用而使其經(jīng)濟(jì)性受到影響。</p><p>　　對(duì)自然循環(huán)能量有效利用的場(chǎng)合就是在由

74、于吸熱的結(jié)果而導(dǎo)致密度有足夠變化的時(shí)候，所以，自然循環(huán)一般限于在低于臨界壓力的設(shè)計(jì)中使用。在這種情況下，蒸汽和水的密度有很大的差異。在壓力高于2900psia時(shí)，自然循環(huán)系統(tǒng)不斷增大,而且價(jià)格昂貴,采用泵可能較為經(jīng)濟(jì)。但是，強(qiáng)迫循環(huán)的原理在起臨界和亞臨界兩個(gè)壓力范圍內(nèi)同樣適用。選用與“通用壓力”這一名稱相符合的鍋爐．反映了直流強(qiáng)迫循環(huán)原理的泛適用性。與在亞臨界壓力范圍內(nèi)保留自然循環(huán)相反，選用強(qiáng)迫循環(huán)主要決定于設(shè)備的經(jīng)濟(jì)性。</p&

75、gt;<p>　　自然循環(huán)在接近于臨界于力的很高壓力下是有效的。自然循環(huán)僅僅依賴于下降管中流體(水)的平均密度與受熱管中流體(蒸汽和水的混合物)的平均密度之差。下降管中的水是來自省煤器的欠熱給水與汽包分離出來的邊和水的混合物，因此這水是欠熱的。爐膛管子中的流體是汽和水的混合物，其密度比下陣營(yíng)中水的密度低，密度之差提供了泵水的壓力，甚至在接近于臨界壓力的很高的壓力下，自然循環(huán)仍然保持有高的有效的循環(huán)壓頭．如圖－3所示。<

76、;/p><p>　　圖－3 壓力對(duì)下降管及上升管內(nèi)的密度的影響</p><p>　　只要在循環(huán)系統(tǒng)中有有效的汽水分離來維持這一差異的最大效果，如采用旋風(fēng)分離器，則可不必借助于機(jī)械來循環(huán)。</p><p><b>　　爐內(nèi)水處理</b></p><p>　　市場(chǎng)上有眾多的化學(xué)藥品，有的被稱作“鍋爐拋光劑”，并被推薦作為“爐

77、內(nèi)”水軟化和其它處理用。它們的作用是穩(wěn)定硬度劑，防止結(jié)水垢或使沉積物易于除掉。這類化學(xué)藥品還用于外部處理后系統(tǒng)中殘余硬度的中和。這種性質(zhì)的化學(xué)藥品是以溶解狀態(tài)，以及近乎恒定的流率供入給水箱或系統(tǒng)中。最常見的化學(xué)藥品是磷酸鹽，磷酸三鈉是最知名的化學(xué)藥品。它與鈣鹽和鎂鹽反應(yīng)產(chǎn)生非溶性磷酸鈣和磷酸鎂。其它的內(nèi)部處理藥劑是氫氧化鈣、鈣酸鈉、氫氧化鈉、丹寧酸和胺。</p><p>　　在投入爐內(nèi)處理化合物的過程中，能保證控

78、制適量程度的最有效方法是采用定量器，它由一個(gè)或多個(gè)帶有人工或機(jī)械驅(qū)動(dòng)的攪拌器的容器和一個(gè)定量泵組成。</p><p>　　一般來說。對(duì)于硬度超過5°（英國(guó)）(70p.p.m)的水，不推薦單獨(dú)使用爐內(nèi)處理。這是因?yàn)橄到y(tǒng)和補(bǔ)水量及水的成分會(huì)變成危險(xiǎn)狀態(tài)，析出的泥渣和鹽容易增加水的密度和泥渣的固化度，同時(shí)隨之在產(chǎn)汽裝置內(nèi)有起泡和蒸濺的傾向，導(dǎo)致水循環(huán)困難。</p><p>　　爐內(nèi)水處

79、理一般限于小型裝置，比如說達(dá)到2～3MW，或作為殘余處理，以及將PH值提高到某一需求值。</p><p><b>　　外部水處理</b></p><p>　　對(duì)于各種規(guī)模的裝置和管網(wǎng)來說，系統(tǒng)中和補(bǔ)充水的外部軟化是更加有效和廣泛使用的水處理方法，它能適合大多數(shù)水質(zhì)。目前外部處理牽涉到離子交換原理，它能確保有硬度為零的水。</p><p>　　離

80、子交換過程可描述如下：溶解的鹽分子在液體溶液中離解成自由荷電離子，在力場(chǎng)中離子被相反電荷所吸引，陽(yáng)離子吸向陰極，陰離子吸向陽(yáng)極。離子交換器是非溶解的人造樹脂，帶有結(jié)合的可離解離子的化學(xué)基團(tuán)附著在樹脂上。按照活性基團(tuán)的離解特性，離子交換劑可分為強(qiáng)活性，中等活性和弱活性三類。</p><p><b>　　陽(yáng)離子交換處理</b></p><p>　　在陽(yáng)離子交換過程中，含鈣

81、鹽和鎂鹽的原水流經(jīng)由鈉鹽基活化的陽(yáng)離子合成樹脂床。鈣鹽和鎂鹽交換成數(shù)量上相當(dāng)?shù)奶妓釟溻c和軟水。</p><p>　　這種中性離子交換并不改變水中的含鹽量和PH值，從而使自由的和結(jié)合的碳酸含量保持不變。由陽(yáng)離子交換過程所軟化的水不含鈣和鎂硬度劑。碳酸氫鈉溶于水，并防止了沉淀。在高于110℃的情況下，碳酸氫鈉可能會(huì)分解，產(chǎn)生部分結(jié)合和全部結(jié)合的二氧化碳，作為腐蝕劑釋放出來。</p><p>　

82、　當(dāng)活性材料由于鈣和鎂的飽和而失敗時(shí)，通過鹽溶液沖洗，使其軟化基能得到再生。鹽溶液中的高濃度鈉離子取代了交換劑中的氯化鈣和氯化鎂，并使其再活化。氯化鈣和氯化鎂隨鹽溶液排入下水道。</p><p>　　對(duì)在生沒有實(shí)際上的限制，交換劑不會(huì)耗盡。在原水中帶有的諸如含鐵量超過0.3mg/L或含錳量超過0.2mg/L的機(jī)械雜質(zhì)的情況下，交換劑可能被污染，從而降低交換能力。如果碰到這種不干凈的水，最好采用預(yù)過濾器。雜質(zhì)在再生

83、過程中不可能從交換器床取出，并且交換劑的經(jīng)常更換成為必要。</p><p>　　陽(yáng)離子交換軟化器由特殊襯里的鋼制圓筒和半滿交換劑組成，并配以適當(dāng)?shù)倪B接口。這種裝置能完全自動(dòng)化，其再生周率由預(yù)定的流通水量，或由測(cè)試所得的硬度來決定。很少需要調(diào)節(jié)水量，除了鹽之外，不需要其它化學(xué)藥品。由兩組設(shè)備相互并聯(lián)，可使其交替再生，從而使過程連續(xù)進(jìn)行。</p><p><b>　　離子交換除礦質(zhì)作

84、用</b></p><p>　　現(xiàn)代高壓裝置的供水的質(zhì)量應(yīng)該是所有的鹽類和溶解硅酸均要被中和。生產(chǎn)蒸汽時(shí)，鹽類應(yīng)保留為沉積物，凝結(jié)水實(shí)際上變成了蒸餾水。</p><p>　　水處理方法發(fā)展的很大進(jìn)步時(shí)由于非溶性人造樹脂的演變。離子交換過程使用樹脂時(shí)為了使得水能達(dá)到現(xiàn)代裝置所要求得純度。在脫礦質(zhì)過程中，水流經(jīng)串聯(lián)得顆粒床交換器，以達(dá)到總?cè)芙夤腆w為5～20p.p.m得純度。<

85、/p><p>　　在陽(yáng)離子交換器里，水中得陽(yáng)離子（鈣、鎂、鈉、鉀）預(yù)氫離子交換，由水溶得鹽生成自由酸。在與陰離子交換器相連接得第二列中，上述酸水失去了自由酸，剩下硅和二氧化碳。這時(shí)，水被完全除鹽。</p><p>　　高度軟化得處理方法用于大多數(shù)電站和需要最佳水純度得制造工藝。對(duì)中小型裝置來說，填充水和補(bǔ)給水不必完全軟化。全部處理過的水，或從附屬和相鄰鍋爐房，或從電站可以獲得的凝結(jié)水，證明最適