Impact of salinity on the population dynamics of microorganisms in a membrane bioreactor treating produced water.

Biomass characteristics may change subject to a salinity increase when treating high strength wastewater. In this study, the impact of salinity in a membrane bioreactor (MBR) was investigated for the treatment of produced water (PW). MBR was operated as a pre-treatment prior to nanofiltration (NF) and reverse osmosis (RO).

Treatment of produced water originated from oil and gas production wells: a pilot study and cost analysis.

Produced water originated from oil and gas production wells was treated by a pilot-scale system including pre-treatment (chemical precipitation), pre-filtration, and post-filtration units. Pre-filtration unit consisted of sand filter, granulated activated carbon (GAC) filter, and ultrafiltration (UF) membrane. Post-filtration unit included reverse osmosis (RO) membrane unit.

Simultaneous removal of ammonium and suspended solids in multipurpose filters.

A multipurpose filter in which sand and clinoptilolite are used together as filter material is suggested for the simultaneous removal of suspended solids and ammonium in one single unit. The capacity of the clinoptilolite used was determined as 10.4 mg/g for 20 mg/l initial ammonium concentration.

A new approach for chemical oxygen demand (COD) measurement at high salinity and low organic matter samples.

Background, Aim, And Scope: Chemical oxygen demand (COD) is used as a discharge standard parameter in wastewater treatment plant design, environmental modelling and many other applications. Chloride interference is an important problem of COD measurement for wastewaters containing low organic matter and high chloride concentrations. In case of chloride concentrations up to 2,000 mg/L, mercury sulphate addition at a ratio of 10:1 (HgSO(4):Cl(-)) can adequately mask the interference.

Joint treatment of landfill leachate with municipal wastewater by submerged membrane bioreactor.

Young leachate was a high strength wastewater with regard to carbon and nitrogen matter, and up to now many researchers have focused on a number of treatment methods to treat the leachate. By using various treatment processes, joint treatment of leachate with domestic wastewater, resulted from same community, is one of the most significant methods because domestic wastewater has either larger mass or lower strength than leachate. In this study, a submerged membrane bioreactor (sMBR) was used for treatment of blending wastewater, including differential mixture ratios of domestic wastewater and leachate.

Stripping/flocculation/membrane bioreactor/reverse osmosis treatment of municipal landfill leachate.

This study presents a configuration for the complete treatment of landfill leachate with high organic and ammonium concentrations. Ammonia stripping is performed to overcome the ammonia toxicity to aerobic microorganisms. By coagulation-flocculation process, COD and suspended solids (SS) were removed 36 and 46%, respectively.

Adaptive neuro-fuzzy modeling of head loss in iron removal with rapid sand filtration.

Breakthrough and terminal head loss are the main parameters that determine the performance of rapid sand filters. Carman-Kozeny and Ergun equations can be applied to estimate head loss, but can only be applied to clean filter beds. Elaborated models are needed to predict head loss in dirty filters.

Modeling of submerged membrane bioreactor treating cheese whey wastewater by artificial neural network.

A submerged membrane bioreactor receiving cheese whey was modeled by artificial neural network and its performance over a period of 100 days at different solids retention times was evaluated with this robust tool. A cascade-forward network was used to model the membrane bioreactor and normalization was used as a preprocessing method. The network was fed with two subsets of operational data, with two-thirds being used for training and one-third for testing the performance of the artificial neural network.

Ozonation of aqueous solution of alpha endosulfan.

Ozonation of alpha endosulfan and the effects of some parameters such as pH, temperature and partial pressure on ozonation were investigated and the kinetic constants were calculated in this study. Alpha endosulfan solutions were ozonated in a lab-scale semi-batch reactor under variable experimental conditions. Increase in dissolved ozone concentration had a positive effect on oxidation rate.