scholarly journals Performance of Ultrafiltration–Ozone Combined System for Produced Water Treatment

2019 ◽  
Author(s):  
Nita Aryanti ◽  
Tutuk Djoko Kusworo ◽  
Wiharyanto Oktiawan ◽  
Dyah Hesti Wardhani
Keyword(s):  
Oil Content ◽  
Produced Water ◽  
Post Treatment ◽  
Separation Performance ◽  
Significant Finding ◽  
Oil And Grease ◽  
Combined System ◽  
Flux Profile ◽  
Benzene Toluene ◽  
Pre Treatment

Oil exploration waste, also called produced water, contains hazardous pollutants, such as benzene; benzene, toluene, and xylene (BTX); naphthalene, phenanthrene, and dibenzothiophene (NDP); polyaromatic hydrocarbons (PAHs); and phenol. Produced water is characterized by high chemical oxygen demand (COD) and oil content, which exceed the standard limits of regulation. In this study, the combination of ultrafiltration (UF) and ozone pre-treatment and post-treatment were applied for treatment of produced water to minimize its environmental impact. Produced water and membrane were characterized, and their ultrafiltration performance for removal of oil content, benzene, toluene, xylene, and COD. Two commercial Polyethersulfone membranes, with molecular-weight cut-off values of 10 and 20 kDa, were used. The membrane flux profile illustrated that ozone pre-treatment had higher normalized flux than UF only. Separation performance was evaluated based on flux profile and removal of COD, oil and grease content, toluene, and xylene. Significant finding was found where the combination of UF with ozone pre-treatment and post-treatment could significantly eliminate COD, oil content, toluene, and xylene. The rejection of these components was found higher than conventional process, which was in the range of 80 % to 99 %. In addition, almost oil and grease can be removed by using this combined system. Permeate quality of this system confirmed the acceptable level as water discharge.

Volume reduction of produced water generated from natural gas production process using membrane technology

2000 ◽  
Vol 41 (10-11) ◽  
pp. 117-123 ◽  
Author(s):  
C. Visvanathan ◽  
P. Svenstrup ◽  
P. Ariyamethee
Keyword(s):  
Natural Gas ◽  
Produced Water ◽  
Hollow Fibre ◽  
Gas Production ◽  
Oil And Grease ◽  
Natural Gas Production ◽  
Pre Treatment ◽  
Selection Of ◽  
Spiral Wound

This paper presents a case study of a natural gas production site covering various technical issues related to selection of an appropriate Reverse Osmosis (RO) system. The long-term field experience indicates the necessity of the selection of appropriate pretreatment systems for fouling-free RO operational conditions. The produced water has a variety of impurities such as oil and grease, process chemicals used for corrosion and scaling control, and dehydration of natural gas, etc. This situation leads to a complicated and extremely difficult task for a membrane specialist to design RO systems, especially the pre-treatment section. Here as part of the pretreatment selection, two types of UF membrane modules viz. spiral wound and hollow fibre, with MWCO of 8000 and 50,000 Dalton respectively, were tested in parallel with NF membranes of the spiral wound type with MWCO 200 Dalton. The UF permeate is used as feed for RO compatibility testing. Both configurations of UF failed to be compatible, due to irreversible fouling of the RO membrane. The NF membrane, however, showed interesting results, due to membrane stability in terms of cleaning and fouling. The NF plant with 50% capacity gave a recovery of 75% and the RO plant gave a recovery of 60% versus the expected 92–95%. The long-term tests have indicated that the reminder of the membranes could be installed to achieve full capacity of the plant. This study also demonstrates the importance of selection of proper pre-treatment set-up for the RO system design.

Methods for Determination of Oil and Grease Contents in Wastewater from the Petroleum Industry

2016 ◽  
Vol 10 (4) ◽  
pp. 437-444 ◽  
Author(s):  
Ilma Cirne ◽  
◽  
Jaime Boaventura ◽  
Yuri Guedes ◽  
Elizabete Lucas ◽  
...  
Keyword(s):  
Oil Content ◽  
Produced Water ◽  
Petroleum Industry ◽  
Infrared Spectrometry ◽  
Residual Oil ◽  
Oil And Grease ◽  
Oil Concentration

Infrared spectrometry and spectrofluorimetry methods were correlated in the measurement of oil concentration in produced water. Furthermore, we compared colorimetry and gravimetry techniques. Adsorption experiments were performed in synthetic oily wastewaters by polymer compounds based on poly(hydroxyethyl acrylamide and polypropylene. The residual oil content was used in the techniques correlation.

scholarly journals Performance, Energy and Cost of Produced Water Treatment by Chemical and Electrochemical Coagulation

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3426
Author(s):  
Chia Miang Khor ◽  
Jinwen Wang ◽  
Minghua Li ◽  
Bruce A. Oettel ◽  
Richard B. Kaner ◽  
...  
Keyword(s):  
Energy Demand ◽  
Oil And Gas ◽  
Produced Water ◽  
Reaction Times ◽  
Oxygen Demand ◽  
Separation Performance ◽  
Oil And Grease ◽  
Water Separation ◽  
Chemical Coagulation ◽  
Water Matrix

The separation performance, energy demand, and operating costs of electro-coagulation (EC) are compared to conventional chemical coagulation for oil–water separation using a simulated oil- and gas-produced water matrix. An iron-based chemical coagulant and sacrificial iron electrodes are evaluated. Effluent turbidity, chemical oxygen demand (COD), total organic carbon (TOC), and oil and grease (O&G) removal were determined for various coagulant concentrations and reaction times and current densities. Chemical coagulation produced superior turbidity removal when scaled by the total iron dose. At lower iron doses (<500 mg/L), chemical coagulation yielded better COD, turbidity, and O&G removal. However, chemical coagulation was unable to effectively remove contaminants to meet the offshore discharge limit of 29 ppm O&G. At higher iron doses, EC was more effective at removing COD and O&G. The energy consumption of EC was found to be much higher even when factoring in the energy of production, transporting, and mixing of chemical coagulants, but the overall cost of EC was approximately half the cost of chemical coagulation, and more effective at O&G removal.

Cytoprotective Effect of Tocotrienol-Rich Fraction and α-Tocopherol Vitamin E Isoforms Against Glutamate-Induced Cell Death in Neuronal Cells

2014 ◽  
Vol 84 (3-4) ◽  
pp. 0140-0151 ◽  
Author(s):  
Thilaga Rati Selvaraju ◽  
Huzwah Khaza’ai ◽  
Sharmili Vidyadaran ◽  
Mohd Sokhini Abd Mutalib ◽  
Vasudevan Ramachandran ◽  
...  
Keyword(s):  
Vitamin E ◽  
Cell Viability ◽  
Neuronal Cells ◽  
Positive Control ◽  
Post Treatment ◽  
Mitochondrial Activity ◽  
Before And After ◽  
Pre Treatment ◽  
Tocotrienol Rich Fraction ◽  
Major Mediator

Glutamate is the major mediator of excitatory signals in the mammalian central nervous system. Extreme amounts of glutamate in the extracellular spaces can lead to numerous neurodegenerative diseases. We aimed to clarify the potential of the following vitamin E isomers, tocotrienol-rich fraction (TRF) and α-tocopherol (α-TCP), as potent neuroprotective agents against glutamate-induced injury in neuronal SK-N-SH cells. Cells were treated before and after glutamate injury (pre- and post-treatment, respectively) with 100 - 300 ng/ml TRF/α-TCP. Exposure to 120 mM glutamate significantly reduced cell viability to 76 % and 79 % in the pre- and post-treatment studies, respectively; however, pre- and post-treatment with TRF/α-TCP attenuated the cytotoxic effect of glutamate. Compared to the positive control (glutamate-injured cells not treated with TRF/α-TCP), pre-treatment with 100, 200, and 300 ng/ml TRF significantly improved cell viability following glutamate injury to 95.2 %, 95.0 %, and 95.6 %, respectively (p < 0.05).The isomers not only conferred neuroprotection by enhancing mitochondrial activity and depleting free radical production, but also increased cell viability and recovery upon glutamate insult. Our results suggest that vitamin E has potent antioxidant potential for protecting against glutamate injury and recovering glutamate-injured neuronal cells. Our findings also indicate that both TRF and α-TCP could play key roles as anti-apoptotic agents with neuroprotective properties.

CONTRACEPTION BY AN INJECTABLE LONG-ACTING OESTROGEN-PROGESTOGEN AGENT. III

1972 ◽  
Vol 69 (1) ◽  
pp. 67-76
Author(s):  
Rolf Plesner
Keyword(s):  
Treatment Period ◽  
Treatment Cycle ◽  
Post Treatment ◽  
Mixed Phase ◽  
Discontinuation Of Treatment ◽  
Phase Type ◽  
Secretory Type ◽  
Pre Treatment ◽  
Long Acting ◽  
Fertile Women

ABSTRACT Twenty-two fertile women were treated cyclically in from 4–30 cycles (mean 15.5) with a total of 341 injections of Deladroxate®, an injectable, long-acting oestrogen-progestogen. The injections were administered on the 8th (7th–9th) day of each cycle. Before treatment, the last pre-treatment cycle was controlled by means of daily recordings of the basal body temperature (BBT), urinary excretion of pregnanediol and total pituitary gonadotrophins at certain intervals, and by endometrial biopsies obtained late in the cycle. The effects of Deladroxate® on ovulation, on pituitary gonadotrophic function, and on the endometrium were controlled by the above mentioned parameters during cycles 1, 3, and 6, and all assessments were repeated after discontinuation of treatment. During treatment, there was a statistically significant fall in gonadotrophin excretion values (as compared with the pre-treatment values), and the fall was found to be gradually progressive during treatment. After discontinuation of treatment, there seemed to be a tendency towards an increase in the excretion values. Suppression of ovulation as determined by means of the pregnanediol excretion during treatment, was effective in nearly all of the treatment cycles checked. The fall in pregnanediol excretion was also gradually progressive during treatment, while there was a slight increase in excretion values in the post-treatment period. During treatment, 79 BBT curves were recorded. Nearly 50 % were monophasic, indicating anovulatory cycles, 17 curves were biphasic, but with the rise in temperature occurring at non-characteristic times in the cycles, 18 curves were classified as thermogenic because of a rise in temperature occurring within 24 hours after the injection, and 5 curves were not assessable. During the first month after discontinuation of treatment, 8 out of 10 recorded curves were monophasic. Out of 53 endometrial biopsies obtained around the 23rd day of the cycle, 31 were of the mixed phase type, but showing a predominance of proliferative patterns, 15 were of the secretory type, and 7 were purely proliferative. Out of 15 biopsies obtained in the post-treatment period, only two were of the mixed phase type, 12 were proliferative and one was purely secretory.

Pre-treatment and post-treatment visual functions in congenital myopia alone versus congenital myopia complicated by amblyopia

2018 ◽  
Vol 75 (4) ◽  
pp. 44-48
Author(s):  
A. Mukhina ◽  
◽  
I. Boichuk ◽  
L. Zhuravliova ◽  
◽  
...  
Keyword(s):  
Post Treatment ◽  
Visual Functions ◽  
Pre Treatment

scholarly journals Relationship between metamorphopsia and inner retinal microstructure following intravitreal ranibizumab injection for branch retinal vein occlusion

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yoshimi Sugiura ◽  
Fumiki Okamoto ◽  
Tomoya Murakami ◽  
Shohei Morikawa ◽  
Takahiro Hiraoka ◽  
...  
Keyword(s):  
Macular Edema ◽  
Retinal Vein Occlusion ◽  
Branch Retinal Vein Occlusion ◽  
Post Treatment ◽  
Intravitreal Ranibizumab ◽  
Vein Occlusion ◽  
Treatment Naïve ◽  
Pre Treatment ◽  
Number Of Injections

AbstractTo evaluate the effects of intravitreal ranibizumab injection (IVR) on metamorphopsia in patients with branch retinal vein occlusion (BRVO), and to assess the relationship between metamorphopsia and inner retinal microstructure and other factors. Thirty-three treatment-naïve eyes of 33 patients with macular edema caused by BRVO with at least 12 months of follow-up were included. The degree of metamorphopsia was quantified using the M-CHARTS. Retinal microstructure was assessed with spectral-domain optical coherence tomography. Disorganization of the retinal inner layers (DRIL) at the first month after resolution of the macular edema (early DRIL) and at 12 months after treatment (after DRIL) was studied. Central retinal thickness (CRT), and status of the external limiting membrane as well as ellipsoid zone were also evaluated. IVR treatment significantly improved best-corrected visual acuity (BCVA) and CRT, but the mean metamorphopsia score did not improve even after 12 months. Post-treatment metamorphopsia scores showed a significant correlation with pre-treatment metamorphopsia scores (P < 0.005), the extent of early DRIL (P < 0.05) and after DRIL (P < 0.05), and the number of injections (P < 0.05). Multivariate analysis revealed that the post-treatment mean metamorphopsia score was significantly correlated with the pre-treatment mean metamorphopsia score (P < 0.05). IVR treatment significantly improved BCVA and CRT, but not metamorphopsia. Post-treatment metamorphopsia scores were significantly associated with pre-treatment metamorphopsia scores, the extent of DRIL, and the number of injections. Prognostic factor of metamorphopsia was the degree of pre-treatment metamorphopsia.

scholarly journals Comparison of Selected Immune and Hematological Parameters and Their Impact on Survival in Patients with HPV-Related and HPV-Unrelated Oropharyngeal Cancer

Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3256
Author(s):  
Adam Brewczyński ◽  
Beata Jabłońska ◽  
Agnieszka Maria Mazurek ◽  
Jolanta Mrochem-Kwarciak ◽  
Sławomir Mrowiec ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Oropharyngeal Cancer ◽  
Hematological Parameters ◽  
White Blood Cells ◽  
Post Treatment ◽  
Neutrophil Lymphocyte Ratio ◽  
Lymphocyte Ratio ◽  
Hpv Status ◽  
Pre Treatment ◽  
The Impact

Several immune and hematological parameters are associated with survival in patients with oropharyngeal cancer (OPC). The aim of the study was to analyze selected immune and hematological parameters of patients with HPV-related (HPV+) and HPV-unrelated (HPV-) OPC, before and after radiotherapy/chemoradiotherapy (RT/CRT) and to assess the impact of these parameters on survival. One hundred twenty seven patients with HPV+ and HPV− OPC, treated with RT alone or concurrent chemoradiotherapy (CRT), were included. Patients were divided according to HPV status. Confirmation of HPV etiology was obtained from FFPE (Formalin-Fixed, Paraffin-Embedded) tissue samples and/or extracellular circulating HPV DNA was determined. The pre-treatment and post-treatment laboratory blood parameters were compared in both groups. The neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), and systemic immune inflammation (SII) index were calculated. The impact of these parameters on overall (OS) and disease-free (DFS) survival was analyzed. In HPV+ patients, a high pre-treatment white blood cells (WBC) count (>8.33 /mm3), NLR (>2.13), SII (>448.60) significantly correlated with reduced OS, whereas high NLR (>2.29), SII (>462.58) significantly correlated with reduced DFS. A higher pre-treatment NLR and SII were significant poor prognostic factors for both OS and DFS in the HPV+ group. These associations were not apparent in HPV− patients. There are different pre-treatment and post-treatment immune and hematological prognostic factors for OS and DFS in HPV+ and HPV− patients. The immune ratios could be considered valuable biomarkers for risk stratification and differentiation for HPV− and HPV+ OPC patients.

scholarly journals Prognostic Relevance of Neutrophil to Lymphocyte Ratio (NLR) in Luminal Breast Cancer: A Retrospective Analysis in the Neoadjuvant Setting

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1685
Author(s):  
Antonino Grassadonia ◽  
Vincenzo Graziano ◽  
Laura Iezzi ◽  
Patrizia Vici ◽  
Maddalena Barba ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Disease Free Survival ◽  
Post Treatment ◽  
Neutrophil To Lymphocyte Ratio ◽  
Luminal Breast Cancer ◽  
Luminal A ◽  
Luminal B ◽  
Lymphocyte Ratio ◽  
Cell Counts ◽  
Pre Treatment

The neutrophil to lymphocyte ratio (NLR) is a promising predictive and prognostic factor in breast cancer. We investigated its ability to predict disease-free survival (DFS) and overall survival (OS) in patients with luminal A- or luminal B-HER2-negative breast cancer who received neoadjuvant chemotherapy (NACT). Pre-treatment complete blood cell counts from 168 consecutive patients with luminal breast cancer were evaluated to assess NLR. The study population was stratified into NLRlow or NLRhigh according to a cut-off value established by receiving operator curve (ROC) analysis. Data on additional pre- and post-treatment clinical-pathological characteristics were also collected. Kaplan–Meier curves, log-rank tests, and Cox proportional hazards models were used for statistical analyses. Patients with pre-treatment NLRlow showed a significantly shorter DFS (HR: 6.97, 95% CI: 1.65–10.55, p = 0.002) and OS (HR: 7.79, 95% CI: 1.25–15.07, p = 0.021) compared to those with NLRhigh. Non-ductal histology, luminal B subtype, and post-treatment Ki67 ≥ 14% were also associated with worse DFS (p = 0.016, p = 0.002, and p = 0.001, respectively). In a multivariate analysis, luminal B subtype, post-treatment Ki67 ≥ 14%, and NLRlow remained independent prognostic factors for DFS, while only post-treatment Ki67 ≥ 14% and NLRlow affected OS. The present study provides evidence that pre-treatment NLRlow helps identify women at higher risk of recurrence and death among patients affected by luminal breast cancer treated with NACT.

Outcomes of surgical and/or medical treatment in patients with prolactinomas during long-term follow-up: a retrospective single-centre study

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Gamze Akkus ◽  
Barış Karagun ◽  
Hilal Nur Yaldız ◽  
Mehtap Evran ◽  
Murat Sert ◽  
...  
Keyword(s):  
Medical Treatment ◽  
Tumour Size ◽  
Optic Chiasm ◽  
Initial Therapy ◽  
Post Treatment ◽  
Surgical Removal ◽  
Average Dose ◽  
Single Centre Study ◽  
Pre Treatment

AbstractObjectivesProlactinoma is the most common cause of pituitary tumours. Current medical guidelines recommend dopamine agonists (cabergoline or bromocriptine) as the initial therapy for prolactinoma. However, surgical removal can also be considered in selected cases, such as patients with macroadenomas with local complications (bleeding or optic chiasm pressure) or those not responding to medical treatment.MethodsThe present retrospective study included patients with prolactinomas (n=43; female, 24; male, 19) who were primarily managed with medical (n=32) or surgical (n=11) treatment.ResultsMacroadenoma (n=29.67%) was commonly detected in both genders (female, 54%; male, 84%). Moreover, the mean pre-treatment prolactin levels were similar in both genders (female, 683.3 ± 1347 ng/mL; male, 685.4 ± 805 ng/mL; p=0.226). Surgically treated patients had a greater reduction in tumour size (27.7 ± 17.9 mm pre-treatment vs. 8.72 ± 14.2 mm post-treatment) than non-surgically treated ones (12.5 ± 7.5 mm pre-treatment vs. 4.1 ± 4.2 mm post-treatment; p=0.00). However, the decrease in prolactin levels was similar between the two patient groups (p=0.108). During the follow-up period (10.6 ± 7.0 years), the average cabergoline dose of the patients was 1.42 ± 1.47 mcg/week.ConclusionsAlthough a surgical approach was considered for selected cases of prolactinoma, the average dose used for medical treatment was highly inadequate for the patients in the present study.

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