ABSTRACT
This chapter provides an overview of produced water (PW) characteristics and treatment technologies. PW constituents are numerous and typically include oil and grease, suspended solids, dissolved solids, heavy metals, radioactive materials, bacteria, dissolved gases, and many other chemicals. These constituents influence the selection of treatment technologies, govern the scope of PW management process, and determine the impacts of various factors on PW treatment practices, particularly in onshore and offshore (oil and gas) production facilities. PW from treatment processes can be reinjected into reservoir, beneficially reused, and/or safely disposed in accordance with prevailing (local) regulations. PW treatment technologies typically focus on removal of residual oil (and grease), suspended solids, dissolved solids, and other contaminants. Treatment technologies for PW management include a pretreatment step (e.g., crude oil separator), primary treatment (e.g., desander, skim tanks, plate pack interceptors, American Petroleum Institute (API) separator, and/or liquid–liquid or solid–liquid hydrocyclone), secondary treatment (e.g., induced gas flotation and dissolved gas flotation), and the tertiary/advanced treatment step (e.g., dual media filters, cartridge filters, and membranes). Treating PW for beneficial reuse has gained significant attention, leading to various emerging technologies that are briefly discussed (e.g., biological treatment technologies, capacitance deionization, humidification dehumidification, mechanical vapor recompression, and crystallization). The basic mechanisms of each technology and their respective uses for PW treatment are discussed, along with their advantages, disadvantages, and waste streams generated. Thus, this chapter provides an overview of current and emerging technologies for treating PW to facilitate their safe disposal, reinjection, and beneficial reuse.
