Dear Sirs,

please contact our agency VAC air Technology AT Sout Africa

by warren@vacair.co.za

phone 0027 11 4727311

May be they can help you

With best regards

VSR Industrietechnik GmbH

47198 Duisburg

Germany

Export Manager

W. Schlabach ■

Hi!

You are not alone with your problem. Many people and companies are loking for solutions to resolve this problem, and only few of them are lucky.

You have very high rate of loading, but widespread kind of cargo and many similar systems for this task were designed.

Basically the construction of dust extraction system depends on the type of your shiploader. Maybe if you can give more information about your shiploaders' design, i will advace you about companies that can really help you.

Best regards. ■

Hugo,

In Australia, all iron ore shiploaders depend on water addition (dust suppression) with a final application at the end of the boom. When the system is well designed and moisture is raised to 4% or 5%, this method is more successful than dust collection.

Once the material has reached the end of the boom, especially at 10,000 t/h, you have no chance of catching the dust.

Michael Reid. ■

Hugo,

Dust extraction doesn't work except where there are enclosures, i.e., transfer chutes, screens etc.

Dust suppression is a process of gradually adding water and maintaining the moisture level from the mine to the port. Trying to add it all in one go causes blockages and mess. Stacking, reclaiming and shiploading are the dustiest operations.

The ports I have direct experience of are Port Hedland and Finucane Island (BHP Billiton), Dampier, Cape Lambert and East Intercourse Island (RioTinto).

I can send contact names by email if you like.

Regards,

Michael Reid. ■

Dust suppression system well used for stacking, but if we are talking about cape size vessels loading: Isn't it means that we have to put abt 4,000 tonnes of water per each 100,000 tonnes of loaded weight? ■

Dust suppression system well used for stacking, but if we are talking about cape size vessels loading: Isn't it means that we have to add abt 4,000 tonnes of water per each 100,000 tonnes of loaded weight? ■

Run of mine ore has an inherent moisture content (sometimes as high as 7% if mined below the water table). The trick with dust suppression is to maintain that at 4% or 5% all the way through processing, stockpiling and reclaiming. It is not necessary to add 4% all in one go. That would be a disaster.

Michael Reid. ■

Hi

Our company supplies equipment of dust suppression system by wetting agent + water spraying.

We have just finished the equipments of 4 ship unloader for Arcelor in France

WWW.ramenvironnement.com

ram@ramenvironnement.com

Contact : Mr Deniel : +33 2 38 46 31 10

GG ■

Several years ago I did a modelling exercise on dust control during shiploading. It was not iron ore, but a dense material that needed to be kept dry.

At that stage, there was nothing available commercially that could control the problem.

I offer a few comments on the process of loading.

The falling orestream entrains air both within itself and as a boundary layer, which causes dusting. This effect has been described by various researchers and is summarised in this paper:

Cooper P, Arnold P C. Air Entrainment and Dust Generation from a Falling Stream of Bulk Material. Kona Powder and Particle No. 13 (1995)

The falling orestream acts like a pump, circulating a load of dust within the hold. If the hold were a piece of fixed plant, one could install baffles to encourage settling. But this is not possible with ship's holds. However, hold geometry can have an effect, and this is described in:

Jünemann R, Holzhauer R. The Reduction of Dust Emissions in Bulk Handling Installations. Bulk Solids Handling, Volume 12, No. 2 May 1992.

The interaction of cross winds with the circulating load of dust in the hold is significant. I doubt that an extraction system alone could cope with it.

In the case of iron ore, I tend to agree with Michael's comments above, which reflect a broader view I have expressed here before and will continue to espouse. Water control throughout the whole process is critical to the end result. ■

I was reflecting on this subject and it occurred to me that this might be one potential application for the use of a foam suppressant.

The concept has been around for a while and I have never seen it used, but in this particular application, if the foam was of suitable consistency and you could fill the hold with it, it might just work. Loading visibility is a first obvious problem.

I leave it to you to hunt it down if you think it worthwhile. ■

Horrors!

First of all, you would have to get sufficient volume of foam and then keep replenishing it, I imagine. You would need to get agreement from customer, ship owner etc. Might have trouble with wind. Probably very expensive.

Seen it used in iron ore conveying, not impressed.

Michael Reid. ■

>>Seen it used in iron ore conveying, not impressed.

LOL! I was not too impressed with the concept when it was first presented to me. I am interested to hear that you have observed it. I wonder if it was a mutual colleague that was the instigator.

I don't know about the costs of foam, but I suspect that a the cost of a cubic meter of foam is insignificantly small in comparison with the cost of a cubic metre of iron ore.

The replenishment rate should be mainly determined by the effects of cross winds I think. And that would be a function of the foam consistency.

Foam could potentially counteract the in-hold circulation that is a key to dust emissions at loading.

Approvals should not be a problem for a single trial.

If it went pear shaped, and large chunks of foam drifted across the harbour, then maybe it could be passed off as an artistic endeavour.

You have to float a few 'out there' ideas or it gets too boring. ■

Dear Sirs,

We have pleasure to inform you that we are manufacturing speciality

chemicals for various industrial applications. We have Dust

Suppression products range 'DUSTRON' for the DUST SUPPRESSION in

mining operation for haulage road in open cast mines and for the bulk

material handling systems.

We have a Memorandum of understanding (MOU) with Central Mining

Research Institute (CMRI) Dhanbad, India which is a part of Council

of Scientific & Industrial Research Govt. of India. CMRI is the world

recognised Institute for the research in the field of mining

operation.

The following products are approved and accepted by the Indian Mining

Industries since last 10 years for better environmental and mining

conditions.

1. DUSTRON PC Compound: For the open cast mines haul road where the

dust emission is because of HEAVY EARTH MOVERS of high capacity

trucks Dozzer, Tippler etc. DUSTRON PC is used for various class of

mines in India for dust suppression in the mines as under.

(1) Iron Ore Mines

(2) Zinc Mines

(3) Lime Stone Mines

(4) Copper/Chromite Mines

2.DUSTRON PC COAL : For the open cast mines haul road of collieries,

railway sidings and coal jetty's road of the ports.

3.DUSTRON PC LIGNITE : For the haulage roads of lignite open cast mines.

4.DUSTRON XT : This product is used for the dust suppression of bulk

material handling system where at the transfer point crusher house,

dumper platform dust emission is heavy, so along with water spray

DUSTRON XT is used to control dust emission.

5.DUSTRON XT COAL : For bulk material handling system of conveyors,

dumper platform, wagon tipplers of open cast/ under ground mines,

Thermal power plants and coal jetty on the port trust.

All the above products are used in Indian mining industries to control

dust for better environment & working conditions which produce no. of

advantages.

We hope that you might be consuming some product for similar

application. "Using DUSTRON RANGE OF PRODUCT SAVINGS IN WATER is 40%"

with other benefits.

If you find any interest we shall send you the detail literature for

your reference along with quotation.

We request you to send us your e-mail address to contact you on net.

E-mail: nrd@juno.com

We ensure you to provide you best services and technical back-up to

your mines for dust suppression applications.

Awaiting for your valued inquiry.

Thanking you,

Yours faithfully

For N R D Industries

DIPALI SHAH. ■