Develop a simple equation to calculate the heat loss due to flue gases in boiler

Devise simplified equation  to calculate the heat loss with exhaust gases in the

boiler that burns heavy fuel oilSalah Salem Ali

Efficiency And Test Senior Engineer Al-HISWA Thermal Power Station -Aden

ssa8027@gmail.com

• This paper had come as a result of practical demand that is finding simple and quick equation, with enough accuracy to calculate the heat loss with exhaust gases (q2) in the boiler, and also count the efficiency (ηg) of the boiler , so that it to be facilitated the specialist researcher to find out (q2), and thus (ηg) immediately without going to the long equations.

Abstract

INTRODUCTION •One of the popular equations to

calculate the heat loss with flue gasses q2 ( russian standard ) is:

Look how it is so long .

•But by the developed simplifiedequation we can get the heat loss with flue gasses (q2) by this simple equation:

2

26fg fg cat t

q

How was the access to this equation?

By indirect method to find the efficiency of :boilers

Multiply each end by :

Putting these values in the previous equation we get the final version of the simplified equation to find the percentage of boiler heat loss with exhaust

gases :

• This extracted equation had been tested and compared its results with the reference test after installation the boiler of AL-HISWA POWER STATION-Aden by the manufacturing authority by hand account method, and also with the tests after the over haul maintenance which had been done by computer application. The comparison results were excellent, so that the error rate in finding out q2 is( -1.91 % max only one time, and maximum error rate of finding out (ηg) is (-0.1%), and sometimes the error for q2 & ηg was zero .

Comparison with the results of reference tests of boiler no.1 Al-Hiswa thermal station – Aden 1986

Comparison with the results of reference tests of boiler no. 2 - Al_Hiswa thermal station-1987

maintenance Comparison with the results of after overall test of boiler no. 3 Al_Hiswa thermal station

2005

No

Data The results

q2 ˬ % ηg ˬ %

Da, t/h tf.g. c0 tc.aˬ C

0 αfg q5ˬ % Test result

By equation

error rate %ˬ

Test result

By equation

error rate %ˬ

Comparison with the results of reference tests of boiler no. 1 - Al_hiswa thermal station - Aden 1986

1 157.4 145 40 1.3 0.64 5.25 5.25 0.0 94.11 94.11 0.0

2 140 145 45 1.384 0.72 5.3 5.32 0.38 93.98 93.96 -0.02

3 123.3 144 40 1.372 0.82 5.42 5.49 1.29 93.76 93.69 -0.07

4 98 135 43 1.44 1.03 5.07 5.10 0.59 93.9 93.87 -0.03

5 96.1 131.5 36.2 1.411 1.05 5.1 5.17 1.37 93.85 93.78 -0.07

6 93.1 132.3 36 1.34 1.08 4.93 4.96 0.61 93.99 93.96 -0.03

7 88.6 137 37.4 1.376 1.14 5.24 5.29 0. 95 93.62 93.57 -0.05

Comparison with the results of reference tests of boiler no. 2 - Al_hiswa thermal station – 1987

1 156.2 142 40 1.195 0.65 4.75 4.69 -1.26 94.6 94.66 0.06

2 156.3 141.5 40 1.208 0.65 4.77 4.72 -1.05 94.58 94.63 0.05

3 139.2 143 40 1.235 0.73 4.93 4.89 -0.81 94.34 94.38 0.04

4 119.7 139 40 1.222 0.84 4.7 4.65 -1.06 94.46 94.51 0.05

5 117.8 139.5 40 1.271 0.86 4.87 4.86 -0.21 94.27 94.28 0.01

6 100.3 140 34 1.359 1.0 5.46 5.54 1.47 93.54 93.46 -0.08

7 78 137 45 1.396 1.3 4.94 4.94 0.0 93.76 93.76 0.0

8 75.6 130 38 1.457 1.33 5.07 5.16 1.78 93.6 93.51 -0.09

Comparison with the results of after overall maintenance test boiler no. 3- Al_hiswa thermal station 2005

1 160.1 144 39 1.4 0.65 5.76 5.65 -1.91 93.59 93.7 0.1

2 160 145 36 1.52 0.65 6.43 6.37 -0.93 92.92 92.98 0.06

3 140.1 146 36 1.50 0.74 6.42 6.35 -1.09 92.84 92.91 0.08

4 140 148 36 1.51 0.75 6.57 6.50 -1.07 92.68 92.75 0.08

5 120.1 149 36 1.53 0.87 6.7 6.65 -0.75 92.43 92.48 0.05

6 120 150 36 1.55 0.87 6.84 6.8 -0.58 92.3 92.34 0.04

7 100.1 152 37 1.74 1.04 7.67 7.7 0.39 91.29 91.26 -0.02

8 100 152 37 1.79 1.04 7.86 7.92 0.76 91.1 91.04 -0.06