Electrochemical Carwash Wastewater Treatment by a new Flow Cell System

Nowadays water is an important issue and water scarcity is one of the main problems around theworld. One of the main ways to solve the problem is wastewater treatment. Water treatment has differentmethods, such as chemical processes, advanced oxidation, biological and enzymatic treatment [۱]. One ofthe most important methods of water treatment is electrocoagulation process. It is an electrochemicalmethod for the production of coagulants and removing colloidal material, metals, suspended solids,pesticides and also harmful microorganisms from water and wastewaters. In this method, a direct current isapplied to a sacrificial anode (mostly Fe or Al). This process (electrodissolution) increases the concentrationof the metal iones (Al۳+or Fe۳) in solution, and these ions are eventually converted to oxides and hydroxides[۲-۴]. This method has been used by many scientists in recent years due to its many advantages such ascheapness, availability and being safe for environment. In this research, wastewater treatment has beenperformed by designing a new flow system for carwash wastewater treatment. It consists of: (I) a columnfilled with activated carbon and sand in order to filtration of large and suspended particles of wastewater,(II) an tunable pump, (III) a tubular flow electrochemical rector consisting of iron cathode and aluminumanode which are connected to a DC power supply. This reactor is the main part of the package. (IV) acolumn after reactor filled with sand in order to remove of generated flocks. In this research, the effectivefactors such as current density, flow rate, electrolysis time and electrodes material, have been optimized.The ۸۸% reduction of COD obtained with this package during a single pass through the system. The treatedwastewater is odorless, colorless and clear and can be used in agricultures and industries.