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LIME DUST
Industrial applications
The main use of Lime Dust is in the construction industry, either as a building material in its own right or limestone aggregate for roadbuilding or as an ingredient of cement or as the starting material for the preparation of builder's lime by burning in a kiln.
Lime Dust is also used in the purification of iron from iron ore in a blast furnace.
Lime Dust is also used in the oil industry in drilling fluids as a formation bridging and filtercake sealing agent and may also be used as a weighting material to increase the density of drilling fluids to control downhole pressures.
Lime Dust is also one of the main sources used in growing Seacrete or Biorock.
Precipitated lime dust, pre-dispersed in slurry form, is also now widely used as filler material for latex gloves with the aim of achieving maximum saving in material and production costs.
Lime Dust is widely used as an extender in paints, in particular matte emulsion paint where typically 30% by weight of the paint is either chalk or marble.
Lime Dust is also widely used as a filler in plastics. Some typical examples include around 15 to 20% loading of chalk in unplasticized polyvinyl chloride (uPVC) drain pipe, 5 to 15% loading of stearate coated chalk or marble in uPVC window profile. PVC cables can use lime dust at loadings of up to 70 phr (parts per hundred parts of resin) to improve mechanical properties (tensile strength and elongation) and electrical properties (volume resistivity).Polypropelyne compounds are often filled with lime dust to increase rigidity, a requirement that becomes important at high use temperatures. It also routinely used as a filler in thermosetting resins (Sheet and Bulk moulding compounds) and has also been mixed with ABS and other ingredients, to form some types of compression molded "clay" Poker chips.
Fine ground lime dust is an essential ingredient in the microporous film used in babies' diapers and some building films as the pores are nucleated around the lime dust particles during the manufacture of the film by biaxial stretching.
Lime Dust is also used in a wide range of trade and do it yourself adhesives, sealants, and decorating fillers. Ceramic tile adhesives typically contain 70 to 80% limestone. Decorating crack fillers contain similar levels of marble or dolomite. It is also mixed with putty in setting stained glass windows, and as a resist to prevent glass from sticking to kiln shelves when firing glazes and paints at high temperature.
Lime Dust is known as whiting in ceramics/glazing applications, where it is used as a common ingredient for many glazes in its white powdered form. When a glaze containing this material is fired in a kiln, the whiting acts as a flux material in the glaze.
Ground Lime Dust (GLD) or Precipitated Lime Dust (PLD) is used as a filler in paper. GLD and PLD are cheaper than wood fiber, so adding it to paper is cost efficient for the paper industry. Printing and writing paper can be made of 10 - 20% lime dust.
would counter the acid in the stream from acid rain and save the trout that had ceased to spawn, it did increase the amounts of aluminium ions in the area of the brook that was not treated with the limestone. This shows that lime dust can be added to neutralize the effects of acid rain in river ecosystems. Currently lime dust is used to neutralize acidic conditions in both soil and water. Since the 1970s, such liming has been practiced on a large scale in Philippines to mitigate acidification and several thousand lakes and streams are limed repeatedly.