Biological Treatment of Synthetic Oilfield-Produced Water in Activated Sludge Using a Consortium of Endogenous Bacteria Isolated from A Tropical Area

Abstract

The aim of this study was to investigate the biological treatment of synthetic oilfield-produced water in activated sludge in an attempt to remove the organic compounds using endogenous bacteria; we also hope to determine the biokinetic coefficients. The activated sludge was operated with various hydraulic retention times (HRT=20 hours, 12 hours, 8 hours), solid retention times (SRT=25 days, 20 days, 15 days, 10 days), and substrate concentrations (500 mg L -1 to 1,100 mg L -1 ). The endogenous bacterial strains, which were isolated from existing wastewater treatment facilities, were identified as Pseudomonas sp., Enterobacter sp., Bacillus sp1., and Bacillus sp2. It was observed that the highest COD removals were obtained in reactors A (80.7%) and B (82.4%), which had high SRTs (25 days and 20 days) and HRT (20 hours). At shorter SRTs (15 days and 20 days), the concentration of the COD effluent did not comply with the Indonesian regulations for oilfield-produced water quality standards, which means that these SRTs were not recommended as appropriate operational conditions. Furthermore, the results showed that the yield (Y), decay coefficient (kd), maximum specific growth rate (k), and saturation constant (K s ) were 0.533 mg MLVSS mg -1 COD, 0.167 day -1 , 0.985 day -1 , and 255.46 mg COD L -1 , respectively. These biokinetic coefficients (obtained from the Y and K s values) indicated that although the strains of bacteria can grow well in the reactor, they had low affinities to the substrate, which caused the concentration of the COD effluent to be relatively high.

Antifouling Property of Oppositely Charged Titania Nanosheet Assembled on Thin Film Composite Reverse Osmosis Membrane for Highly Concentrated Oily Saline Water Treatment

“…However, with the increasing oil concentration in the oily saline feedwater, the amount of emulsifier was not sufficient to provide full coverage on the oil droplets, resulting in destabilization and partial coalescence of the oil droplets. Consequently, the average oil droplet particle size was increased [ 38 ]. Apart from this reason, the oil droplet size distribution is also known to be influenced by the presence of NaCl.…”

“…The synthetic oily saline solution was prepared by mixing the salt solution with crude oil [ 38 ]. The water was prepared by mixing crude oil in the range of 1000–10,000 ppm and SDS at the ratio of 9:1.…”

Biological-Based Produced Water Treatment Using Microalgae: Challenges and Efficiency

“…Kardena et al [45] investigated the biological treatment of the synthetic oil field PW in activated sludge to remove organic compounds and determine biokinetic coefficients. The isolated endogenous bacterial strains Pseudomonas sp., Enterobacter sp., Bacillus sp1., and Bacillus sp2.…”

Artificial produced water as a medium to grow Chlorella sp. for biodiesel production

“…was Walne media. The artificial produced water used in this study refered to the characteristics of produced water from an Indonesian oil field, located in Balikpapan [11]. The chemicals used to make artificial produced wastewater were crude oil, NH4Cl, phenol, KNO3, KH2PO4 and Na2S.…”