Thermal and mechanical evaluation of the stability of recycled poly(ethylene terephthalate) applied as sand control agent in petroleum wells

Evaluation of chemical and mechanical resistance of virgin and recycled poly (ethylene terephthalate) and poly(methylene oxide) when applied as gravel pack in petroleum wells

“…The conclusions of the previous work [1] were reinforced by the results obtained in the short term exposure tests, i.e., the new proposed use for recycled PET aggregates value to this material, since, as a sand control agent, there is no necessity of any additional treatment, besides the conventional recycling process [19][20][21] . That also improves PET recycling attractiveness in general, contributing to environment preservation.…”

“…After characterization, polymer samples (PET vir , PET rec and PMO) were placed inside individual cells made of steel N316 and Hastelloy C276, prototypes developed by PETROBRAS [1] . Each cell, with capacity for 443 mL each, was filled with 300 g of the polymeric samples and the respective liquid medium.…”

“…The mechanical strength of the polymeric gravel pack was evaluated using an API permeability cell [1] , according to API standards for granular agents applied in gravel packing operations [9,10] . A thin layer of polymer grains was disposed in the cell and then compressed at 13.8 MPa and 70 °C simulating the confinement stress over a gravel pack system observed in oil wells.…”

“…A previous work [1] , where PET and PMO were exposed to seawater and petroleum environments, already has shown the good potential for those polymers as gravel packs. Nevertheless, an exposition of these polymers, to more aggressive media which simulates conditions that polymers would have to face when used for gravel packing oil producers or water injection wells, is still needed.…”

“…One of those new proposed applications is in oil well building, where conventional polymers, as poly(ethylene terephthalate) (PET) and poly(methylene oxide) (PMO) can find new unexpected uses as, for example, granular materials (gravel) in underground sand filters (gravel packs). Moreover, even recycled PET has the necessary characteristics to be used in the same way, once its properties were found to be similar to the virgin material, potentially opening a new front for polymer recycling [1] . Is important to notice that the main Brazilian oil fields are composed by mechanically fragile sandstone formations [2,3] , meaning that all the wells installed in those fields need to be equipped with some kind of sand control system to prevent the contamination of the oil production with sand.…”