scholarly journals Treatment of Oil Wastewater Containing High Salinity with Ultrafıltratıon (UF) and Reverse Osmosıs (RO)

The high salinity oil wastewaters contained high salt, chloride, total hydrocarbon concentrations with COD and TSS. In order to treat this wastewater a sequential UF and RO ractor system was used. Before membrane treatment the oil was floated with an API oil separator. The effects of increasing fluxes ( 12 L/h, 30 L/h and 50 l /h) and pressures (4 bar , 8 bar and 16 bar ) on the removals of pollutant parametres were studied in the UF. The influence of the main operating parameters suh as operating pressure (15, 35 and 50 bar), temperature (25, 40 and 55 °C) and feed flowrate (7, 14, 28 L/min, were studied in RO. The maximum salt , chloride, total hydrocarbon, COD,dis-COD, and TSS yields were 90%, 91%, 89%, 89%, 89% and 90%, respectively, at a flux of 60 L/m2.h and at a pressure of 16 bar in UF, respectively. The maximum RO yields in the permeate were around 99% for the pollutant parameters given above at afed flowrate of 28 L/min at 24 bar pressure.

2007 ◽  
Vol 56 (8) ◽  
pp. 161-168 ◽  
Author(s):  
A.R.A. Razak ◽  
Z. Ujang ◽  
H. Ozaki

Endocrine disrupting chemicals (EDCs) are the focus of current environmental issues, as they can cause adverse health effects to animals and human, subsequent to endocrine function. The objective of this study was to remove a specific compound of EDCs (i.e. pentachlorophenol, C6OCL5Na, molecular weight of 288 g/mol) using low pressure reverse osmosis membrane (LPROM). A cross flow module of LPROM was used to observe the effects of operating parameters, i.e. pH, operating pressure and temperature. The design of the experiment was based on MINITABTM software, and the analysis of results was conducted by factorial analysis. It was found that the rejection of pentachlorophenol was higher than 80% at a recovery rate of 60 to 70%. The rejection was subjected to increase with the increase of pH. The flux was observed to be increased with the increase of operating pressure and temperature. This study also investigated the interaction effects between operating parameters involved.


2011 ◽  
Vol 418-420 ◽  
pp. 90-93 ◽  
Author(s):  
Lin Ji ◽  
Ying Liu ◽  
Yu Feng Zhang ◽  
Xun Dao Liu

Taking reverse osmosis (RO) technology for the treatment of high salt containing oil waste water as the example, this study investigated the relationship between the pressure and the permeate flux, the stability of the membrane module and the membrane cleaning cycle. The results show the feasibility of RO technology for the treatment of high salt containing oil waste water.


Author(s):  
Leonid S. Bobe ◽  
Nikolay A. Salnikov

Analysis and calculation have been conducted of the process of low-pressure reverse osmosis in the membrane apparatus of the system for recycling hygiene water for the space station. The paper describes the physics of the reverse osmosis treatment and determines the motive force of the process, which is the difference of effective pressures (operating pressure minus osmotic pressure) in the solution near the surface of the membrane and in the purified water. It is demonstrated that the membrane scrubbing action is accompanied by diffusion outflow of the cleaning agent components away from the membrane. The mass transfer coefficient and the difference of concentrations (and, accordingly, the difference of osmotic pressures) in the boundary layer of the pressure channel can be determined using an extended analogy between mass transfer and heat transfer. A procedure has been proposed and proven in an experiment for calculating the throughput of a reverse osmosis apparatus purifying the hygiene water obtained through the use of a cleaning agent used in sanitation and housekeeping procedures on Earth. Key words: life support system, hygiene water, water processing, low-pressure reverse osmosis, space station.


Membranes ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 61
Author(s):  
Thomas J. Ainscough ◽  
Darren L. Oatley-Radcliffe ◽  
Andrew R. Barron

Groundwater contamination by chlorinated hydrocarbons represents a particularly difficult separation to achieve and very little is published on the subject. In this paper, we explore the potential for the removal of chlorinated volatile and non-volatile organics from a site in Bedfordshire UK. The compounds of interest include trichloroethylene (TCE), tetrachloroethylene (PCE), cis-1,2-dichloroethylene (DCE), 2,2-dichloropropane (DCP) and vinyl chloride (VC). The separations were first tested in the laboratory. Microfiltration membranes were of no use in this separation. Nanofiltration membranes performed well and rejections of 70–93% were observed for synthetic solutions and up to 100% for real groundwater samples. Site trials were limited by space and power availability, which resulted in a maximum operating pressure of only 3 bar. Under these conditions, the nanofiltration membrane removed organic materials, but failed to remove VOCs to any significant extent. Initial results with a reverse osmosis membrane were positive, with 93% removal of the VOCs. However, subsequent samples taken demonstrated little removal. Several hypotheses were presented to explain this behavior and the most likely cause of the issue was fouling leading to adsorption of the VOCs onto the membrane and allowing passage through the membrane matrix.


2020 ◽  
pp. 249-258
Author(s):  
Costin Mircea ◽  
Florin Nenciu ◽  
Valentin Vlǎdut ◽  
Gheorghe Voicu ◽  
Iuliana Gageanu ◽  
...  

Rotary seed sorters used for wheat processing show some functional advantages in eliminating persistent contaminants, especially due to the more aggressive treatment applied to the processed material. The objective of this paper was to design a new constructive subassembly that would increase the performance of rotary sorters used for extracting various contaminants from seeds. By testing a pilot stand that reproduces the operation of a professional equipment and developing mathematical models that fits the main operating parameters, it was possible to identify the new characteristics needed to improve cylindrical sieves and to optimize the functioning of this equipment.


2020 ◽  
Author(s):  
Mengyan Hu ◽  
Yinyao Lin ◽  
Xuejiao Men ◽  
Qiang Zhu ◽  
Danli Lu ◽  
...  

Abstract Background: High salt diet (HSD) is one of the major risk factors for acute ischemic stroke (AIS). As a potential mechanism, surplus salt intake primes macrophage towards a proinflammatory phenotype. The study investigated whether HSD could blunt efferocytosis of macrophage after ischemic stroke, which was a vital process that alleviated post stroke neuroinflammation. Besides, the underlying mechanism was explored.Methods: Wild type male C57/Bl6 mice were fed with fodder containing 8% sodium chloride for 4 weeks and subjected to transient middle cerebral occlusion (tMCAO). Disease severity, macrophage polarization as well as their efferocytic activities were evaluated. In in vitro study, bone marrow derived macrophages were cultured and the impact of high salinity environment on their efferocytic capacity, as well as their expression of phagocytic molecules were analyzed. The relationship of sodium concentration, macrophage phenotype, and disease severity in AIS patients with ischemic stroke was explored. Results: HSD-fed-mice displayed increased infarct volume and aggravated neurological deficiency. Mice fed with HSD suffered exacerbated neural inflammation as higher level of inflammatory mediators and immune cells infiltration were documented. Polarization shift towards pro-inflammatory phenotype impaired efferocytosis of infiltrated macrophages within stroke lesion in HSD-fed-mice were detected. As was uncovered by PCR array, macrophage expression of triggering receptor expressed on myeloid cells 2 (TREM2), a receptor relevant with phagocytosis, was down regulated in high salt environment. Enhancing TREM2 signaling restored the efferocytosis capacity and cellular inflammatory resolution of macrophages in high salinity environment. In AIS patients, high concentration of urine sodium was correlated with lower expression of TREM2 and detrimental stroke outcomes.Conclusions: HSD blunted efferocytic capacity of macrophages through down regulating the expression of TREM2, thus impeded inflammatory resolution after ischemic stroke. Enhancing TREM2 signaling in monocyte/macrophage could be a promising therapeutic strategy to enhance efferocytosis and promote post-stroke inflammatory resolution.


2013 ◽  
Vol 68 (9) ◽  
pp. 1994-1999 ◽  
Author(s):  
Muhammad Umar ◽  
Felicity Roddick ◽  
Linhua Fan

The UVC/H2O2 process was studied at laboratory scale for the treatment of one moderate (conductivity ∼8 mS/cm) and two high salinity (∼23 mS/cm) municipal wastewater reverse osmosis concentrate (ROC) samples with varying organic and inorganic characteristics. The process efficiency was characterized in terms of reduction of dissolved organic carbon (DOC), chemical oxygen demand (COD), colour and absorbance at 254 nm (A254), and the improvement of biodegradability. The reduction of colour and A254 was significantly greater than for DOC and COD for all samples due to the greater breakdown of humic compounds, as confirmed by fluorescence excitation-emission matrix spectra. Fairly small differences in the reduction of DOC (26–38%) and COD (25–37%) were observed for all samples, suggesting that the salinity of the ROC did not have a significant impact on the UVC/H2O2 treatment under the test conditions. The biodegradability of the treated ROC samples improved markedly (approximately 2-fold) after 60 min UVC/H2O2 treatment. This study indicates the potential of UVC/H2O2 treatment followed by biological processes for treating high-salinity concentrate, and the robustness of the process where the characteristics of the secondary effluent (influent to RO) and thus resultant ROC vary significantly.


2018 ◽  
Vol 67 (3) ◽  
pp. 211-217 ◽  
Author(s):  
Vo Huu Cong

Abstract This research aims to provide an overview of the seawater encroachment threat on agriculture in lowland areas and potential solutions for better practices. It was found that the Mekong river delta experiences severe impacts from climate change with more than 75% of provinces affected by seawater intrusion, of which Kien Giang, Ca Mau and Ben Tre provinces are the most influenced with 70% affected areas. The salinity of river water was observed in the range of 15–30 g/L in 2015; meanwhile, the strongest tolerated rice species reached ceiling values of 3–4 g/L. Emerging challenges were identified due to the uncertain upstream hydrological regime coupled with high levels of tide, field evaporation and water withdrawal. The development strategies of affected provinces are given on the modification of rice tolerant capacity, and modification to aquaculture in areas with high salinity, in which water purification is in urgent demand. Desalination technologies have been proposed with various innovations which are still not practical on a large scale. The desalination of seawater and brackish water by reverse osmosis, nano-filtration, electro-dialysis, ion-exchange resins, electrochemical processes and thermal distillation has been applied to agriculture. The advance reverse osmosis shows most potential because of its advances in treating performance, cost effectiveness and effective rejection of brine.


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