Re: Cement Transport Checks
Dear James,
To comment the proposed solutions and compare the new installations with your existing installation, the following, additional, information is necessary:
1)the compressor type (roots type blower or screw compressor with internal compression)
You mention “blower” (maximum pressure 0.8 to 1.0 bar, which could explain the larger pipe diameter)
2)Feeder system
Double pressure tank system or screw-feeder (FK pump)
3)What is the conveying length (horizontal and vertical) of the existing installation, what is the conveyed product,airflow and pressure?
A compressor should deliver oil free compressed air to a pneumatic conveying system.
The type of compressor (isochoric or adiabatic compressing principle) determines the energy consumption.
The choice of the compressor (Aerzen or Fuller or other) has to be made by yourself, based on quality, price, service and references.
Awaiting the additional information
Best regards
Teus. ■
Teus
Re: Cement Transport Checks
Existing system is same run almost - mill 1.
Feeder is screw pump FL type
Data is
Existing System Data
Existing Pipeline :
250NB Schedule 40
Existing Pneumatic Conveying Equipment
Cement Pump - Fuller
Installed Motor: 150kW (Full Load Current = 340amps)
Blower - FULLER KOVAKO. C-608. S.S.
Right hand discharge
Installed motor: 285kW (Full Load Current = 602amps)
Rated Normal. Pressure - 30 PSIG. - 2900 CFM.
Maximum Pressure - 40 PSIG. - 344 BHP.
Existing Cement Conveying Data
Cement Pumping case for approximately same line :-
108tph GP 3300 Blaine to Silo
Pressure Readings:
At pump discharge - average reading 15psi, variation 15 to 20psi pressure
Pump motor amps - 189 to 211amps
Existing Flyash Blend Conveying Data
Cement/Flyash Blend Data for calibration purposes
100tph GP plus 20tph fly ash = 120tph to FA Bin
Pressure Readings
At pump discharge - variation 14 to 16psi
Blower Motor amps = 436 amps
Pump amps = 187amps ■
Re: Cement Transport Checks
Hi Teus
Blower will be rotary vane or screw type
Feeder is screw pump type
Exist mill pipe run is almost the same as new line - data has been sent in last post.
Cheers
James ■
Re: Cement Transport Checks
Hi James,
Does it mean that on the existing pipeline that;
108 tons/hr cement is achieved on the 143m+43m 10"pipeline at 15 psi
and that ;
120 tons/hr FAB is achieved on the 107m+34m 10"pipeline at 15 psi
Br
Teus ■
Teus
Re: Cement Transport Checks
Hi Teus
Yes it does......but GP is higher and further - but lower rate...surges a bit - last leg is vertical up silo wall.
Cheers
James ■
Re: Cement Transport Checks
Teus,
GP is 134m h and 49m vertical
FAB is 107 horiz and 23m vertical
Cheers
James ■
Re: Cement Transport Checks
Hi james,
I run the various installations through the computer and summarized the results in a word-file, which is attached as a zip-file to this message.
I hope that I understood your description right.
It is recommendable to investigate the performance of the existing installations thoroughly and base the design of the new installations on the derived pneumatic conveying properties of the cement and fly ash blend (I followed that procedure)
Then take into account the necessary air velocities (as low as possible) and pressure limitations of the FK pumps.
(Take in mind that a FK pump consumes approx 0.7 kW/ton conveyed)
Certainly a job for an experienced expert.
success
teus
Attachments
existing installation rj morrish (ZIP)
■
Teus
Re: Cement Transport Checks
Hi Teus
Thanks for that
The offers that our consultant has received is for 300mm line and 2 compressors (unknown capaicty)
Your screen shots show a low velocity at the start - I do not know what a minimum should be. Perhaps this is the reason for 2 compressors being selected....this will then result in higher velocities all round.
Cheers
James ■
Re: Cement Transport Checks
James,
If I recall correctly, the blowers at Callide Power Plants Lurgi Bag Filter plant were Aerzen (the unit was a Hurll Nu-Way effort).
As the plant should have been operational for a few years now maybe they could provide some feedback for you?
Don’t know about Fuller.
Regards,
Lyle ■
Re: Cement Transport Checks
Thanks Lyle,
I will give them a call.
The other supplier claims that their compressor to be very robust but we have had some unexpected failures that have occured at the wrong time and led a few $$$ lost. One was a cracked bore thru the water jacket. I am not so sure of their claim
Cheers
James ■
Re: Cement Transport Checks
Hi James,
When using a FK-pump system, the number of compressors is irrelevant for the system..
Or it must be for backup purposes. And even then it is easy to rent an oil filled, mobile screw compressor as used on a building site.
When using a double kettle system, one compressor could deliver air to the tanks and the other serves as a booster.
The minimum air velocity at a certain location in the pipeline should be 1.5 to 2 times the local suspension velocity.
As the air density in the beginning of the pipeline is high, due to the higher pressure, the local air velocity can be lower. The expansion of the convey air along the pipe line automatically increases the air velocity.
To prevent a too high air velocity (with the related too high energy losses) the pipeline diameter is stepped up.(not always done)
The consultant should make clear how the system, he offers, is designed.
Often, a consultant keeps that for himself for commercial reasons (you could compare with competitors and thereby revealing knowledge) but you will find out anyway when the system is built, although it might be too late then.
I have experience with Aerzen oil free screw compressors with internal compression and vane compressors.
The Aerzen compressors are to prefer over vane compressors as the latter are not oil free and more vulnerable to dirt.
An Aerzen compressor in pneumatic conveying is just a compressor block with a drive motor. (no auxiliary equipment around it)
Take care
teus ■
Teus
Cement transport checks
Hi All,
We are proposing a transport system for
HE cement 3800blaine - 100t/hr
Fly Ash Blend FAB cement - 200tph - 3350 Blaine GP x 75% and +5000 Blaine fly ash 25%
GP cement - 3350 Blaine 140t/h down to 4300 Blaine at 100t/hr
Runs are all in one line to 3 silos/bins
FAb/HE Bins - 107m horiz, 23m vertical and 4 bends (located side by side)
GP silo - located after FAB/HE . total 134m horiz and 49m vertical and 8 bends ie larger/higher silo.
Some have suggested a 300mm line and 2 blowers.
Considering that we have a 250mm line for 150tph for same silos on other mill, this seems like a large step up.
Would appreciate any comments.
Also....running with 2 blowers does not seem a reliable solution. What are peoples experience on the Aerzen compressors cf Fuller compressor
We have limited real estate on exist small silos to fit larger venting filters.
Cheers
James ■