A major steel plant on the east coast of Sweden has recently installed a new rolling mill. In conjunction with this, they've introduced the principle of 100% recycling of both the process water and slag resulting from the cooling process. As part of their effort to implement this, they've installed a DynaSand filtration plant.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/swedish-steel-plant-goes-green-and-avoids-clogging-continuous-sand-filters
[2] http://admin.indiaenvironmentportal.org.in/category/author/steve-minett
[3] http://admin.indiaenvironmentportal.org.in/category/journal/everything-about-water
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/wastewater-recycling
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/sweden