Abstract: A method and apparatus for improving mixing of fluids has at least two static mixing stages connected in series with a bypass valve connected in parallel across each but the last of the mixing units. The capacity of each downstream mixing unit should be such that its minimum flow requirements overlap the opening point for the check valve of the preceding mixing unit. Pressure drops exceeding predetermined limits cause the bypass valves to open allowing fluid flow therethrough thereby preventing further pressure drop through the mixing unit.

Abstract: The invention is a method for isolating a sample of oilfield production without shearing the sample, which includes a multistep method of using a chamber to isolate a sample of fluid from a flowline by transferring the sample from the flowline without a significant pressure drop. This involves placing a valved isolation chamber in fluid communication with a sampling port of an oilfield production flowline, the isolation chamber consists of a closed vessel, a first entry port into the vessel, and a first exit port out of the vessel controlled by a first valve. The sampling port valve is opened while the first valve of the isolation chamber is closed to permit pressure within the isolation chamber to equalize with pressure within the flowline. The first valve is then opened to permit oilfield production to pass from the flowline through the sampling port and the first entry port into the isolation chamber and out of the first valve.