火力发电厂设计毕业论文

300MW火电机组机务部分局部初步设计

排污冷却器的计算：补充水温tma=20℃,取排污冷却器端差为8℃，

?????则 hma?hma?hb1?28?4.1864?hh1?117.2192

锅炉连续排污系统计算

?h1??bh1???由排污冷却器热平衡式 ?ma(h?m?)?) b1ahma?1(b??1? hb?1hb???b?117.2192??ma11

??b1?1??ma0.00485?742.64?0.98?117.2192?0.015187 =267.63KJ/Kg

0.00485?0.98?0.015187 =

??hb??1?28?4.1864?hma 于是 hma??1?8?4.1864 =hb =267.63-33.49

=234.14KJ/Kg

二、计算汽轮机各段抽汽量?Dj和凝汽流量Dc

1、由高压加热器H1热平衡计算求?1 (见图3-1)

?1? =?fw(hw1?hw2)

q1?h1.043862(1137.5?1029.1)

(3133.05?1131.8)?0.99 (图3-1) =0.05711

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毕业设计（论文）

2、由高压加热器H2热平衡计算求?2 (见图3-2) ?fw?2??sg1(hsg1?hs2)?h??s1(hs1?hs2)?h ?2?q2?h (图3-2) =

1.043862?(1029.1?825.48)?0.004429(3394.45?1029.1)?0.99?0.05711(1131.8?1029.1)?0.99(3049.3?1029.1)?0.99

=0.09819

H2的疏水?s2

?s2??1??2??sg1=0.05711＋0.09819＋0.004429=0.159729 再热蒸汽量?rh

?rh?1??1??2=1-0.05711－0.09819＝0.8447 3、由高压加热器H3热平衡计算求?3 (见图3-3)

已知给水在给水泵中的焓升为

pu?4?hw4?741.3?715.5?25.8 ?hw?hw?fw?3??sg2(hsg2?hs3)?h??s2(hs2?hs3)?h (图3-3) ?3?

q3?h

?1.043862?(825.48?741.3)?0.004053(3535.66?825.48)?0.99?0.159729?(1029.1?825.48)

(3343?825.48)?0.99 =0.01797

H3的疏水?s3

?s3??s2??3??sg2?0.159729?0.01797?0.004503＝0.181752

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300MW火电机组机务部分局部初步设计

4、由高压加热器H4热平衡计算求?4

?除氧器出口水量?fw 如图除氧器物质平衡,求凝结进水量?c? ?fw??4??sg3??s3??f??c??(?fw??sg3??f??s3)??4 ?c =(1.043862-0.013233-0.005484-0.181752)-?4=0.843394-?4

除氧器的热平衡式 (见图3-4)

?4??fwhw4/?h??fhf??sg3hsg3?0.8256hw5h4?hw5

=（1.043862?701.86/0.99-0.005484?2776.4

-0.013233?3028.44-0.843394610.65-0.1817 52?825.48）/（3163.2－610.65）

=0.00772 ??0.843394?0.00772?0.835674 故 ?c (图3-4)

5、由低压加热器H5热平衡计算求?5 (见图3-5)

?5???50.835674?(610.65?530)?c ?q5?h(3045.9?623.2)?0.99 =0.0281 (图3-5)

6、由低压加热器H6热平衡计算求?6 (见图3-6)

?6???6??5(hs5?hs6)?h?c

q6?h =

0.835674?(530?376.94)?0.0281(623.2?540.6)?0.99

0.99?(2935.1?540.6) (图3-6) =0.05299

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毕业设计（论文）

H6疏水

?s6??5??6?0.05299?0.0281?0.08109

7、由低压加热器H7热平衡计算求?7 (见图3-7)

?7???7??s6(hs6?hs7)?h?c

q7?h =

0.835674?(376.94?223)/0.99?0.08109(540.6?38732)

(2721.6?387.2) (图3-7) =0.05034 H7的疏水

?s7??s6??7?0.08019?0.05034?0.13143

8、由低压加热器H8、轴封冷却器SG和凝汽器热井构成一整体的热平衡计算求?8

(见图3-8)

(图3-8)

热井的物质平衡 ?1~7??1??2??3??4??5??6??7

=0.05711＋0.09819＋0.01797＋0.00772＋0.0281＋0.05299＋0.05034

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