Dear Mr. Chowdhury,

I'm interested in giving you a quotation for this pneumatic conveying plant.

For that I need you inform:

- Horizontal distance

- Vertical distance

- Nr. of elbows and respective degrees (90º, 60º, 45º, 30º, etc)

- Temperature of ash

- Discharge method from the 8 hopers to the system

- Capacity and height of silo

It should be helpful if you could send me an isometric scheme.

Best Regards

Sousa Mendes (Tech. Mngr and Partner)

Aeraulica, Lda

Mail: aeraulica@net.sapo.pt ■

Dear , Prasenjit1971

From the info you stated in your thread, the following can be concluded.

From

Dust load 3 gr/m3 = 0.003 kg/m3

Dust generation 500 kg/hr

resulting in:

500/0.003 = 167800 m3/hr of gas = 2800 m3/min = 47 m3/sec

From

particle size = 73% below 5 microns

average suspension velocity of particles = approx. 0.4 m/sec

(assumed material density = 2200 kg/m3)

To collect the dust, a vacuum system is needed of very big proportions.

At a filter load of 0.8 m/min (because of the very fine particles, requiring low gas velocities and high efficiency filter material), the required filter area is approx. 2800/0.8 = 3500 m2

With a duct velocity of 2 m/sec (5 times the suspension velocity),

the duct area = 47/2 = 23.5 m2

In this evaluation, no oversize or safety factor is included.

The above figures to be divided over the 8 hoppers.

The filter system itself must also be of a special construction and design for efficient self cleaning.

The gas flow has to be generated by centrifugal fans.

From the filter receiver hoppers the dust has to be collected into blow tanks.

The pressure conveying from the blow tanks to the silo is then a pneumatic conveying system, that can be purchased from the market.

It can consist of 1 blower of approx 1m3/min at 1 bar(o) switched to one of the 8 blow tanks at a time, unloading that blow tank in approx 5 min on a 4 inch pipeline ( approx 2.1 m/sec velocity)

The 8 blow tanks are connected to the main conveying pipeline by valves.

The silo has te be equipped with a high efficiency filter and over-/under pressure safety valve,

NOTE: It is strongly advised to consult proven experts and manufacturers in this field, to prevent mistakes and loss of time and money.

The installation, you are referring to, is too big to do this by yourself, unless you have extensive experience and knowledge.

success

teus ■