Dust and noise are two main working environment problems in beneficiation plant. Although the auxiliary equipment like dust collectors are not main mining machine in plant, they are equally important. There are many good measures to deal with dust and noise problems and widly used in many plants such as iron ore processing plant, gold mining euqipments , coal plant etc.

1.Dust collection

The dust removal and dust collecting systems are very similar to a normal dry classification circuit. Dry classification is in fact a dust removal system where the max size of the dust is controlled by a classifier (or ventilation criteria), See figure 1

Figure 1. dust collection system

Primary recovery of dust is normally done in a cyclonedust collector taking the major part. The final recollection is done in a wet scrubber or a fabric filter. Wet scrubber has an advantage over fabric filter when the dust is combustible. In all other cases the dry fabric filtration is more effective as no sludge handling is required (being the case with wet scrubbers).

2.Noise control

There are 4 main ways to reduce the noise levels for processing systems including crushers, ball mills and vibrating screens.

2.1.Optimum operation

Mass flow equipment like jaw crushers and screens are normally lower in noise when they are operated under optimum conditions and the material flow is absorbing part of the noise (e.g. choke fed cone crushers). Reduced circulating loads also lead to reduced noise levels.

2.2.Internal polymers

The use of polymers as mill liners, screening media and wear protection in material handling systems (chutes and transfer points) have a dramatic effect on noise reduction. For grinding mills a rubber lining can reduce the noise level up to 10 dB(A) compared to a steel lining. See fig2.

2.3.External polymers

Using polymers as dust sealing enclosures of cone crushers, screens,belt conveyors, chutes, transfer points etc. will give a noise reduction of approx. 5-10 dB (A). The difference for a screen with steel wire deck and rubber deck is shown fig3.

Figure 3. difference for a screen with steel wire deck and rubber deck

2.4.Noise reduction walls

Enclosure is an effective way of reducing noise. Enclosure can be more or less extensive (enclosure of drive or machine or both). With a total enclosure noise levels can drop by 10-15 dB (A).