Water separation method and apparatus

A method of treating fractionated water from an oil and gas well, the method comprising:

• providing a fractionated water stream produced via hydraulic fracturing of an oil and gas well;
• straining the fractionated water stream with a plurality of straining filter banks;
• diffusing a filtered stream through a plurality of diffusive membrane banks;
• detecting the total dissolved solids level at the outlet of each of the plurality of membrane banks using a membrane sensor;
• and
• selectively disengaging at least one of the plurality of membrane banks if the total dissolved solids level ranges from about 20,000 ppm to about 40,000 ppm to produce a blended water stream, and
• mixing a bypassing fractionated water feed with at least one permeated water stream produced by the plurality of membrane banks to produce a blended water stream, wherein the membrane controller is programmed to selectively disengage at least one of the plurality of membrane banks to produce a blended water stream having a total dissolved solids level ranging from about 20,000 ppm to about 30,000 ppm.

A system for treating fractionated water from an oil and gas well, the system comprising:

• a filter system, a diffusive membrane system, a plurality of membrane sensors, and at least one membrane controller, wherein the filter system is fluidly connected to the diffusive membrane system,
• wherein the fractionated water comprises water having a total dissolved solids level ranging from about 30,000 ppm to about 100,000 ppm,
• wherein the filter system comprises a plurality of straining filter banks,
• wherein the plurality of straining filter banks each comprise a plurality of bag filters,
• wherein the diffusive membrane system comprises a plurality of membrane banks each having an inlet and an outlet, wherein the plurality of membrane banks each comprise a plurality of reverse osmosis membranes,
• wherein the plurality of membrane sensors are positioned at the outlet of each of the plurality of membrane banks, and the plurality of membrane sensors are configured to detect the total dissolved solids level at the outlet of each of the plurality of membrane banks,
• wherein the at least one membrane controller is programmed to selectively disengage and isolate at least one of the plurality of membrane banks from fluid communication with the system upon detection if the total dissolved solids level at the outlet of one or more of the membrane banks is above about 20,000 ppm,
• further comprising a connection configured to mix a bypassing fractionated water feed bypass with an at least one permeated water stream from the plurality of membrane banks to produce a blended water stream, wherein the membrane controller is programmed to selectively disengage at least one of the plurality of membrane banks to produce a blended water stream having a total dissolved solids level ranging from about 20,000 ppm to about 30,000 ppm.