condenser 1

[sar1281]

From
B.Saravanan,
Reg.No (1998304)
B.E (MECH. Engg pre final year)
M.N.Regional Engg. College
Allahabad-211004,
Uttar pradesh,
India.




Subject: -project work on condenser


Respected sir,
I wish to furnish the technical details pertaining to my scope of study on condenser performance

Condenser details

Steam side

S.no Details units value
1 steam from turbine exhaust kg/hr 442,182

2 Enthalpy of steam kcal/kg 580.87

3 steam saturation temperature degree 45.7
Celsius
4 Condenser heat load kcal/hr 237,240,875

5 moisture content 7.5%


Water side

s.no Details units value
1 circulating water flow cubic
meter/hr 29,100

2 circulating water inlet temperature degree 34
(Design) Celsius

3 circulating water outlet temperature degree 42.5
Celsius
4 velocity of water m/s 2

5 differential pressure across condenser ksc 0.5

6 Design condenser back pressure mm of 74.68
(OR)
Hg 0.1015
Condenser Construction details

Total number of tubes =19,661 nos.

Outer Diameter =25.4 mm

Thickness =1.24 mm

Material cupronickel ASTM-b-111-90/10

Type of condenser

Surface condenser, single shell, divided water box .two pass, perpendicular to turbo generator axis

Problem faced

During summer the cooling water temperature rises by 5 c from 34 c to 39 c .As a result of which the condenser vacuum drops to the threshold value which some times leads to load reduction .The scope of the project work involves reduction in circulating water inlet temperature from 39 c to 34 c during peak hours (1300 hrs to 2000 hrs). At present the problem is temporarily solved by starting the third cooling water pump (normally the cooling water pumps are in service)
In these regard I request you to kindly send me your valuable suggestions ,based on which I can carry out further studies .I vouch that the suggestions given by you will be solely used for my studies pertaining to this project work
I am eagerly awaiting an early reply
Thanking you,
Yours faithfully
B.Saravanan.

 

[MJCronin]

sar1281,

It sounds like your temperature increase, from 34C to 39C (93F to 102F)is quite modest for a winter to summer swing. This type of swing would be expected in a steam surface condenser with cooling provided from a cooling tower. Developing more backpressure on the turbine during summertime service should be expected, but not so much as to cause to cause the unit to trip offline:

Some important information that you left out:

- Location of Plant ? Tropics? What is ambient wet bulb?
- Type of Cooling Source ? Cooling Tower ? Ocean ?
- Total area of Condenser ?

What type of service is the steam surface condenser in ? Electric Power generation ? Process power ?

I also suggest that you refer to your uni as a "Steam Surface Condenser" to prevent confusion.

If your task is to somehow drop the summertime temperature of the cooling water below what is reasonable for a cooling tower, your boss needs an eduction in thermal cycles.

Hope that this helps ???!!!......................MJC

 

[packdad]

If your circ water heat sink is a cooling tower, you may be able to increase the tower efficiency by modifying the spray & fill pattern to achieve a better spray distribution (ie, eliminate dead zones). There are companies that will provide this type of analysis for you if you wish. You can email me for more information. (An engineer I work with recently coordinated this type of project for our plant.)

Other than that, I don't know what else to say! I assume a physical modification to the condenser is out of the question. Cleaning/inspecting the condenser might be in order if you suspect a change in performance over time due to fouling. Just remember that things DO get hotter in the summertime! Hard to change that if you deal with lakes, rivers, oceans, or cooling towers...