Methods and systems for treatment of wastewater. In some embodiments, the system may comprise one or more modules such as an electrochemical module, an electrocoagulation module, a flotation module, an evaporation module, and an ultrafiltration module. One or more detection modules may also be provided to analyze the concentration of one or more wastewater components in the wastewater. Data from such modules may be used to adjust one or more operational parameters or conditions in the treatment system. The system may also comprise one or more features designed to minimize adverse effects on the environment, such as avoiding adding chemicals to the stream, extracting salt or other chemicals for re-use, and/or use of carbon dioxide gas from on-site combustion processes.