We are operating a 940 TPD wet process rotary kiln using industrial waste materials such as calcium carbide sludge and limestone. Our plant is located in  India.We are using high chloride and high sulfur sludge resulting in kiln backend draft increase and kiln ring formation in the pre burning zone of the kiln. However, performance of kiln ESP is satisfactory and meeting our pollution norms. We are interested to know from you whether there is any solution to prevent/remove the kiln rings and reduce kiln draft.