Compact wastewater concentrator and contaminant scrubber

A process for removing contaminants from flowback water from a natural gas well, the process using a wastewater concentrator including a gas inlet, a gas outlet, a concentrating section between the gas inlet and the gas outlet, the concentrating section having a narrowed portion, the process comprising:

• mixing a reagent with liquid flowback water from a natural gas well, the reagent reacting with a soluble chemical compound in the liquid flowback water to form an insoluble chemical compound;
• combining a gas and the liquid flowback water in the concentrating section to form a mixture of gas and entrained liquid flowback water, the entrained liquid flowback water including the insoluble chemical compound;
• directing the combined gas and entrained liquid flowback water into a demister where at least some of the entrained liquid flowback water is removed from the gas and collected in a sump of the demister;
• removing a portion of the liquid flowback water in the sump of the demister and sending the portion of the liquid flowback water to a settling tank where suspended solids and insoluble chemical compounds in the liquid flowback water separate from liquid portions of the liquid wastewater;
• removing the separated solid portion from the settling tank and returning the separated liquid portion to the demister sump.