why IBD Vent is kept at higher elevation than CBD ?
Answer Posted / shahnawaz ahmad
Intermittent blowdown better known as bottom blowdown or mud drum blowdown is done to remove undissolved solids from the mud drum of a boiler or from the bottom of the shell of a fire tube boiler. Some boilers operated at high pressure with super clean water dont need this very often. The pipe from the mud drum goes to a tank the purpose of which is to reduce the pressure to atmospheric and to reject heat so that the water/mud mixture is cool enough not to damage the sewer lines or whatever fixtures it flows to. This tank is the intermittent blowdown tank or the atmospheric blowdown tank since it is vented to atmosphere.
The continuous blowdown tank is a flash tank used to collect heat from the water that is continuously drawn from the steam drum in order to control the dissolved solids. As water is boiled off to steam in the steam drum anything that will not evaporate is left behind and this will increase the concentration of dissolved solids in the boiler water. This is bad because the solids will precipitate out and form scale which must be removed chemically and water with high solids concentration will start to foam which will cause level control problems and will also result in material carrying over with the steam resulting in deposits in the superheater tubes and headers. To control this some of the high concentration boiler water is drawn off and replaced with lower concentration feed water.
This flows to a tank at a lower pressure than that in the drum and some of the water flashes to steam, which can be used to heat feedwater or what have you. The liquid left over can be used in a heat exchanger to heat make-up water or it can flow through a standby boiler to keep it warm and to maintain the chemicals in the water or to the circulating water in a cooling tower or to the atmospheric blow down tank.
| Is This Answer Correct ? | 5 Yes | 1 No |
Post New Answer View All Answers
procedure of how to generate power in solar plant.
what is the trip circuit supervision in an electrical meaning?
explain how the third harmonic content of the magnetising current affects transformer design
How to calculate power press toneage
can u please tell me how to calculate the concrete quantity for a under reamed pile? r=300mm,depth=3m for a cylinder and for bulb l=.750mm,width=.525
dear sir i have completed one year post diploma certificate in thermal power engineering from national power training institute durgapur ...plz suggest me for power sector job
our 125 kva DG does not start in AUTO mode works normally in MANUAL mode please give me a solution.....
LAPT working in alternator / generator
How We Calibrate the vaccum transmitter?
We have Demin Closed cooling water system with expansion tank for cooling oil system. Expansion tank having N2 bladder. Whenever N2 bladder bursts out, Closed cooling water circuit pressure drops and make-up happening, eventhough there is no leaks. And how Circuit pressure drops?
why is the in steam turbine axial displacement of active side thrust pad is positive and non active side thrust pad is negative.
some one can tell me how residual type excitation is provided through transformers to an AC generator without any battery or PMG&excitor
what is the basic use of power plant in equipment
What is difference between secondary Air & Tertiary Air and Their use.?
how to differentiate between "ALL fuel lost" and "All Fuel Lost" in Boiler MFT condition?