When kiln hood draft is made negative i.e. from -0.2 mmwg to -0.5 mm wg , what should happen to the cooler vent fan power and preheater ID fan power.
Er.Hussaini
I'll Try !
The Answer to this lies on the fact that how did make the change from -0.2 to -0.5 . Let me guess you have two option you either increase PH ID fan speed if it is Speed control which inturn increases -ve pressure ( so ID fan power will increase ) or you might have reduced vent fan speed/decreased resistance by opening damper to shift null point which also increases -ve pressure i.e -0.2 to -0.5 in this vent fan power should decrease. What are the other probablities??
I hope i have answered!!
Er.Raza Hussaini
Asst.Manager
B.tech.,(Chemical engg)
babli
Thank You sir very much for ur answer
Kumar
Generally the kiln hood draft is controlled in auto by increasing or decreasing the cooler vent fan speed.As you have increased the hood draft from -2 to -5 it means either vent fan has to increase its speed or open damper to maintain it.hence fan load will increase a little bit.whereas a marginal reduction or no change will take place in your PH fan load as this much reduction in its air quantity will be compensated by the little increased ingress of false air from the kiln seals or from the PH.