Oil based drilling fluid waste: an overview on environmentally persistent pollutants.

Operational discharges of spent drilling fluid, produced water, and accumulated drill cuttings from oil and gas industry are a continuous point source of environmental pollution. To meet the strict environmental standard for waste disposal, oil and gas industry is facing a numerous challenges in technological development to ensure a clean and safe environment. Oil and gas industry generates a large amount of spent drilling fluid, produced water, and drill cuttings, which are very different in every drilling operation in terms of composition and characterisation. This review article highlights the knowledge gap in identifying the different sources of waste streams in combined drilling waste. This paper also emphasises how different chemicals turn into environmentally significant pollutants after serving great performance in oil and gas drilling operations. For instance, oil based drilling fluid performs excellent in deeper drilling and drilling in the harsh geological conditions, but ended with (produces) a significant amount of persistent toxic pollutants in the environment. This review paper provides an overview on the basic concepts of drilling fluids and their functions, sources and characterisation of drilling wastes, and highlights some environmentally significant elements including different minerals present in drilling waste stream

The crystallinity and thermal degradation behaviour of polyamide 6/oil based mud fillers (PA6/OBMFs) nanocomposites.

The crystallinity and thermal degradation behaviours of Polyamide 6/Oil Based Mud Fillers (PA6/OBMFs) nanocomposites have been investigated using DSC and TGA. TGA indicates the onset decomposition temperature of D1/2 (half-decomposition) is 16º C higher for PA6 with 10.0 wt.% of OBMFs than that of PA6, whereas the lowest onset decomposition temperature difference among the nanocomposites and neat PA6 is 8º C for PA6 with 7.5 wt.% of OBMFs. However PA6 with 5.0 wt. % OBMFs nanocomposite has taken the longest time (1minute 36 seconds more than neat PA6) to reach D1/2. It can be deduced in this study that PA6 with 5.0 wt. % OBMFs nanocomposite provided the maximum heat resistant property whereas PA6 with 7.5 wt. % OBMFs nanocomposite showed the maximum heat absorbance property among different nanocomposites and PA6 with 10.0 wt. % exhibited the maximum thermal stability. There is a sigmoidal curve generated based on the TIF and wt% filler content value which shows three significant points at intersections of 50% TIF line which are highlighted as exfoliation (4.2 wt.%), intercalation (6.8 wt.%) and agglomeration (9.0 wt.%) points. These TIF values explained the investigated heat resistant, heat capacity and thermal stability properties of PA6/OBMFs nanocomposites illustrating the ratio of TIF and MAF is the key measure which can be considered as an effective approach to identify the nanomorphology of PA6/OBMFs nanocomposites