A dewatering treatment for oily sludge using geotextile filters

It is well known that waste from the petroleum industry has a high environmental impact. Conventional systems for oil-water separation are used to mitigate the contamination potential of the effluents. The oily slurry formed on the bottom of these separation systems has high concentration of contaminants making the disposal of this slurry is an environmentally hazardous practice. Normally it is disposed of in tanks or landfills after removal from an industrial plant. The present work presents an alternative treatment for this oil slurry to mitigate the environmental impacts and reduce the cost of disposal. Basically, the technique consists of using drying beds with geotextile filters to reduce the water content in the slurry and obtain a less contaminated effluent. Some laboratory tests were carried out to simulate the drying system. Four types of filters were analyzed: two non-woven geotextiles, one woven geotextile and a sand filter.