You cannot exceed the MAWP for the tanker tub which is normally 2 bar g. If you intend to supplement the airflow once the discharge has started you ought to convey more powder up to the top of the silo. Your air inlet connection will have to match the threaded connection on the vehicle tank: not difficult but definitely not 8". Using 8" line downstream will simply slow down the air. ■

Dear skientzy,

Unloading a cement bulk truck on an 8” pipeline and 60 m up, with the support of a 28 m3/min booster is very well doable.

According to a preliminary calculation, a capacity up to 80 to 100 tons/hr must be possible.

Velocities were a bit high.

For a proper calculation, some extra information is required.

-Bulk truck volume

-Maximum allowable tank pressure

-Bulk truck cement content

-Bulk truck compressor data (displacement and maximum pressure)

-Bulk truck outlet pipe size

The filter on top of the silo needs to be designed for the full airflow

A over- and under pressure safety valve must be mounted on to of the silo

Two level testers must be installed (1 high level and 1 high/high level)

High level gives an alarm

High/high level closes a valve in the pipeline.

have a nice day

Teus ■

Dear skientzy,

The maximum pressure in your system is limited by the bulk truck blower of 12 psi # 0.84 bar.

Using only the 500 cfm blower (0.236 m3/sec), the 8”pipeline will choke.

Using only the 700 cfm blower (0.33 m3/sec), the 8”pipeline will result in approx. 36 tons/hr at 0.84 bar with sedimentation.

Below a pressure of 0.45 bar there is no sedimentation, which means that the pipeline can be purged.

Using the 500 cfm blower (0.236 m3/sec) with the booster of 1000 cfm (0.47 m3/sec) results in approx. 48 tons/hr at 0.84 bar

Using the 700 cfm blower (0.33 m3/sec) with the booster of 1000 cfm (0.47 m3/sec) results in approx. 48 tons/hr at 0.84 bar

Attached a possible setup of the installation.

success

Teus

Attachments

bulktrucksilobooster (PDF)

■

The booster point pressure will be balanced by truck pressure and conveying quantity. Cement will not choke in 20" pipe bore as it may change smoothly between dense phase and dilute phase, especially in vertical pipes.

Place the truck as close as possible to the mixing point helps enlarging the discharging capacity. ■

Dear shenjie,

How much air would you use for the 20" pipe for what capacity and pressure?

Is the difference between the bulk truck outlet of 4"or 5" and the pipe of 20" not a too great difference?

I am curious

have a nice day ■

Originally Posted by Teus Tuinenburg

Dear shenjie,

How much air would you use for the 20" pipe for what capacity and pressure?

Is the difference between the bulk truck outlet of 4"or 5" and the pipe of 20" not a too great difference?

I am curious

have a nice day

Sorry it was 8" in stead of 20" ■

Hello Gentlemen,

When you consider this system @ 8" internal diameter you must consider the pipe bends and their life as it will be very costly to repair the back sections when they wear.

We have experience with many systems such as this and it is without doubt that you need a wear protected bend and section after each piece.

You will also need to consider the coupling and any reducer sections of pipe.

If you want any help with this contact me directly as we can help you in your design. ■

Dear TREVORH,

I have witnessed many cement conveying installations in the past 19 years, which have conveyed millions of tons and can state that the wear in pipelines, diverters, branches and standard mild steel 1.5D bends is minimal.

In case of a leak, it is in most cases enough to weld a box over the hole and continue for years.

The worst place where you can have a leak is where a poorly closing valve wears the valve seat and the adjacent flange. By the time you notice that leak, there is some work to do.

Success

Teus ■

Please check what kind of surplus compressor you have there. Is it really a compressor or a blower? In case it is a compressor take good precautions to separate any water or oil out of your compressor air in case it is an oil injected screw compressor. Please mind you that you potentially use more power with such a compressor over a dry single stage screw compressor or a blower.

Good luck, ■