Processing of Iraqi Attapulgite For Using as Drilling Muds: A Comparison Study

Clay mineral processing is in charge on quality, quantity and functional properties of final produced clay. In this work, Iraqi attapulgite (Palygorskite) clay was processed with dry sieving, dispersing agent and wet sieving processes to make it suitable in oil and gas wells drilling fluids preparation. Yield of clay (quality) and yield of process (quantity) were taken as preferring criteria in choosing the proper process of Iraqi attapulgite clay preparation. XRD and FESEM tests were used for mineralogical and morphological identification respectively. OFITE viscometer was used to measure the rheological properties of the drilling fluids prepared with the produced attapulgite from the investigated processes. The results of this work showed that dry sieving process was failed in attapulgite separation. Moreover, dry grinding was a destructive process of the attapulgite crystalline structure which reduced the rheological properties up to 80%. The results showed that the dispersing agents process produces attapulgite clay with higher quality (101.94 and 89.87 barrle/ton) with fresh and salt water respectively and at low quantity of about 7%. While wet sieving process produces attapulgite clay with quality equals to (94.21 and 79.93barrel/ton) with fresh and salt water respectively and quantity reaching 40%. It follows that wet sieving was the recommended process in preparing Iraqi attapulgite to be suitable for oil and gas wells drilling fluid