LAUSR

The expansion of shale gas production requires characterization and correct management of the residues generated by the activity, due to their high polluting potential. This work is a literature data consolidation on the physical–chemical characterization of the effluents generated in the production stage. Comparison of effluent characterization with the limits established in the Brazilian legislation revealed that the oil and grease, barium, toluene, and xylene (m, p) content in the raw effluent exceed the limits for disposal into water bodies, reaching values 29 and 633 times above the limits for oil and grease and barium content, respectively. The values of total dissolved solids, nitrate, sulfate, aluminum, arsenic, barium, chlorides, chromium, copper, iron, lithium, manganese, nickel, phosphorus, lead, antimony, selenium, zinc, benzene, toluene, ethylbenzene, xylene (m, p, o), and styrene exceed the quality standards of Class 2 water bodies from at least 2 times to 1225 times (toluene) and 4527 times (barium). A comparison between the effluent treatment technologies used in the shale gas production activity supports the proposition of a combination of processes that could efficiently remove contaminants considered most relevant, consisting of oil/water separator tanks or hydrocyclones, coagulation/flocculation and flotation, biological treatment or advanced oxidation processes, chemical precipitation, direct osmosis, and UV disinfection, if necessary.