Study on Opencast Coal Mine Haul Road Dust Suppression using Guargum Grafted Polyacrylamide

Abstract

Vehicle movement over haul road is the major source of fugitive dust emission from opencast coal mines which adversely affect the environment. Water spraying is the most common practice for controlling fugitive dust generationfrom haul road. In this work, an innovative polymer was synthesised to study its effectiveness as a dust suppressing agent. Guargum grafted polyacrylamide (GG-g-PAM) polymer was synthesised by free radical polymerisation technique using Ceric Ammonium Nitrate (CAN) initiator. Haul road dust sample was collected from a mine and characterised by sieve analysis and Energy Dispersive X-ray (EDX) analysis. An experiment was carried out at controlled environment in the oven to measure the moisture retention efficiency of the dust applying the synthesised polymerat different temperatures 25°C, 35°C and 45°C. For this purpose, 0.1 weight percentage of GG-g-PAM was mixed with water. The solution was sprayed over 20g dust sample (below 10 mesh size) in a petri dish. The same experiment was repeated with only water as the dust suppressant to compare with the effectiveness of GG-g-PAM. The experiments showed that application of GG-g-PAM polymer solution instead of only water helps to increasing moisture retention capacity of haul road dust by 12.9% after 8 h at 25°C, 14.7% after 8 h at 35 °C, and 25.4% after 2 h at 45°C. It is also observed that application of GG-g-PAM polymer solution helped in reducing the dust generation by 36% after 8 h at 25°C, 32% at 35°C after 6 h, and 65% after 2 h at 45 °C. This shows that during scorching summer when the temperature is, in general, above 40°C, GG-g-PAM solution has potential for suppression of haul road dust in opencast coal mines effectively.