Alkali Effect on Alkali-Surfactant-Polymer (ASP) Flooding Enhanced Oil Recovery Performance: Two Large-Scale Field Tests’ Evidence

Table 13

Injection water comparison.

Block	Ca^2+, mg/L	Mg^2+, mg/L	Cl, mg/L	, mg/L	, mg/L	, mg/L	K^+ + Na^+, mg/L	TDS, mg/L	pH
SASP	37.17	10.33	832.8	2226.39	289.66	NA	1549.83	4968.18	7.97
WASP	40.1	12.2	895.1	3065.2	63.1	6	1718.4	5800.1	8.4