Recovery optimization of membrane processes for treatment of produced water with high silica content

Abstract

2011) Recovery optimization of membrane processes for treatment of produced water with high silica content, Desalination and Water Treatment,[297][298][299][300][301][302][303][304][305][306][307][308][309] To link to this article: http://dx. A B S T R A C TDisc tube (DT) and spiral wound (SW) configurations of nanofiltration (NF) and reverse osmosis (RO) processes were tested at pilot-scale using a two-pass configuration to treat produced water obtained from natural gas wells. First pass NF membranes were used to remove divalent cations from produced water. Permeate from the first pass NF membranes were used as feed to second pass RO membranes after increasing the pH to 10.0 to enhance silica solubility. To reduce the fouling potential on NF and RO membranes dissolved air floatation (DAF), ceramic ultrafiltration (UF), MYCELX cartridges, and organoclay filters were tested as pretreatment alternatives. Pretreatment processes were effective for turbidity and oil and grease removal but were not efficient in retaining organic matter, primarily protein-like and polysaccharide-like material, which eventually fouled the first pass NF membranes. The second pass RO membranes were scaled predominantly by silica. The overall feed water recovery of the two-pass NF-RO system was limited to less than 70%. Although the application of a two-pass configuration met the discharge limits for most of the contaminants in produced water, a more stringent pretreatment process for selective removal of organics and silica is essential to operate the membrane systems at recoveries greater than 85%. If treated appropriately, produced water can be employed as a true water resource to augment existing surface water streams and creeks.

Polymeric membranes for produced water treatment: an overview of fouling behavior and its control

“…Biofouling in the membrane processes consists of two major steps: attachment (bioadhesion and bioadsorption) and growth (multiplication). The properties of the microorganism, the solution, and the membrane surface morphology control the bioadhesion, whereas micronutrient availability controls the biofilm growth (Ivnitsky et al 2005, Subramani et al 2011, Guo et al 2012. Like colloidal fouling, the RO membrane with rough surface is more likely to form biofilm during PW treatment than the smooth membrane surface of NF (Alzahrani et al 2013c).…”

A Tale of Two Foulants: The Coupling of Organic Fouling and Mineral Scaling in Membrane Desalination

“…While each of these studies alone does not provide sufficient evidence that electrocoagulation is effective in simultaneously removing organic matter and silica, they might motivate future studies to investigate its efficiency when both constituents are present. Ho et al 174 and Subramani et al 175 both studied various pretreatment options, including coagulation, ultrafiltration, organoclay filters, and MYCLEX cartridges, which showed varied removal of organic matter but low removal (<15%) of silica. A thorough search of the literature failed to find a promising treatment process proven to remove >50% of both organic matter and silica.…”

Silica treatment technologies in reverse osmosis for industrial desalination: A review

“…However, alkali feeding conditions are liable to cause the scale formation by hardness and metal ions such as iron and manganese. Hence, the main design feature is the multiple pretreatment processes to achieve extreme reduction of the hardness and metal ions [66].…”