A large amount of wastewater in the form of oil-in-water is generated in different industries such as olive mills, metal processing and offshore oil and gas. The wastewater treatment equipment market was worth >€1 billion in 2010. All the industries face the same problems: to separate emulsified oil from water in a cost-effective way and to handle large volumes of oily waste in an economical way. Among available technologies membrane processes exhibit undisputable advantages over the conventional approaches, especially in treatment of highly emulsified oily wastewater.
The O-WaR project aims to develop an integrated process able to efficiently remove emulsified oil from wastewater, to reuse treated water, to recover by-products in wastewater and to reduce volumes of oily waste for disposal. Our solution consists of a SiC membrane coated with an anti-fouling layer, an Induced Gas Flotation (IGF) unit for membrane concentrate treatment and a NF/RO unit for purification of SiC permeate and/or valuable by-products recovery from wastewater.
The O-WaR technology will be able to remove >99% of oil, solids and chemical oxygen demand, making treated oily wastewaters to easily meet discharge or reuse requirements, and produce <2% oily waste for off-site disposal, greatly reducing waste disposal cost. In the case of olive mill wastewater (OMW) treatment the O-WaR technology can effectively recover valuable by-products in OMW and create high values (up to €700/kg of recovered small phenolics for functional food, nutraceuticals and cosmeceuticals) for the industry. With the O-WaR technology we expect an annual profit of €1.4 million generated in an OMW treatment plant (20,000 m3/year capacity) and a total annual OPEX savings of €0.17 million for a metal processing factory with 20,000 m3/year wastewater produced compared to using a conventional technology. Also, the SMEs in this project are predicted to have a market opportunity of €11.7 million in first 5 years post project.
“An integrated membrane process for oily wastewater treatment, water re-use and valuable by-products recovery – O-WaR«; EU Research for SME (FP7-SME-2013; Project nummer 605641), 2014-2015.
Aquateam COWIs assignment
The aims of the project was to develop an integrated process for removal emulsified oil from wastewater, to reuse treated water, to recover by-products in wastewater, to reduce volumes of oily waste for disposal and to improve the quality of discharged wastewater.
Research was aimed for the benefit of specific group (Small and Medium Enterprises) related to treatment wastewater in the rural areas with limited access to proper methods wastewater treatment.
Pilot scale testing of oily wastewater (olive mill wastewater and steel wastewater) were carried out. Pretreatment by coagulation and flotation (DAF Nikuni system). Treatment by SiC (silicon carbide) ceramic membrane system (ultra/nanofiltration), membrane pore size 0.04 µm.