Dust Suppression for Conveyors and Transfer Points
The movement of conveying crushed stone, coal, or sand, stirs up and creates a dust cloud, which can be suppressed by spraying water as a fine mist or fog. Adding finely sprayed water to the mineral at transfer points and hoppers can prevent the generation and spread of excess dust. The dust cloud can also be lessened or prevented from forming at all by adhering the dust to the mineral being processed with a small amount of sprayed water.
For this dust suppression to be effective, it is crucial to get the right sized droplet to do the job effectively. In most applications, droplets should be 1 to 5 times the size of the dust that is being controlled. If the drops are too small, they will be unable to envelop the dust particles. Conversely, drops which are too large form an air barrier around themselves, preventing the dust from gaining direct contact and encapsulation.
Selecting a Conveyor Washing Nozzle:
If you wish to reuse water, you should select a nozzle with a free passage that is large relative to the flow rate, such as the low flow, Hollow Cone spiral L series which produces the correct size droplet and are cost-effective, durable, and ideal for transfer points.
Clog-resistant MaxiPass nozzles offer unparalleled free passage for liquids with large particulates or soft solids and provide a Full Cone spray with several spray angles.
Large free passage TFXP spiral nozzles, which are also for liquids with large particulates or soft solids, are a durable one piece construction, very efficient, create fine atomization, and come in a wide variety of flow rates.
You may also consider Flat Fan nozzles that are designed to spray a moving conveyor belt with an even coating. BETE’s NF series nozzles are a durable one-piece construction, clog resistant, and can spray at angles from 0° to 120°. For extra wide angles, the FF series nozzles have the same features as the NF and can spray up to 145° via a deflected angle design. The NFD series produce a Flat Fan spray up to 120° and add a dovetail feature on the base of the tip so that the spray pattern is guaranteed to be oriented correctly when removing and replacing the tips.
Stubby NFS nozzles are as short as possible, spray a variety of fan angles, and come in standard connections of straight threads, either NPSM or BSPP. High impact SPN nozzles are a heavy one-piece deflected-fan construction with low spray angles for maximum force transmission.
All of BETE’s nozzles are machined by professionals to ISO 9001 quality standards.
Most nozzles come in standard materials of Brass, 303 Stainless Steel, and 316 Stainless Steel although some can be manufactured from PVC, PTFE, or other materials. Our experienced engineers can help determine which nozzle is best for your application. For typical dust control applications, Brass is the most economical choice.
Dust suppression on conveyors is commonly used in the mining and quarrying industries or anywhere a dust-prone material is moved automatically. Dust control via water spray is also used in the transfer of coal, though water addition is limited so as to minimize net heat output on firing.
Typical operating conditions for this application are listed for each nozzle