Evaluation of electrowet coalescer in series with PVDF-HFP electrospun fiber membranes for separation of water from ULSD

Water in diesel fuel is a significant issue in the petrochemical industries as it causes diesel engine corrosion and maintenance problems. Efficient removal of water from diesel fuel is necessary to protect the diesel engine. In this work, water drop emulsions of drop sizes in 2-80 µm size range in ultra low sulfur diesel fuel were pre-coalesced by flow through an electrowet coalescer prior to flowing through flat and tubular electrospun PVDF-HFP fiber membranes. Experimental results showed the separation efficiencies of 90-95% for membranes alone improved significantly to greater than 99% when the water drops were pre-coalesced by the electrowet coalescer. The power required to operate the electrowet coalesce and flow through the membranes was less than the power required flow through the membranes without the electrowet coalescer to achieve similar separation efficiency.