Abstract: Systems and methods of collecting, treating, and recycling oilfield drilling fluids, used oilfield water, and other wastewater are disclosed. A separator may be used to separate a fluid mixture into one or more liquids and one or more solids. Water, oil, or other liquids may be recovered from the separator and further processed by aeration, filtration, and/or pasteurization, making them suitable for reuse in oilfield drilling and/or fracking operations or other industrial applications, such as truck or equipment washing. Sludge from the separator may be dried to produce dried solids, which may also be used for various applications, such as road base.