scholarly journals A Pilot Study of an Electromagnetic Field for Control of Reverse Osmosis Membrane Fouling and Scaling During Brackish Groundwater Desalination

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1015 ◽  
Author(s):  
Wenbin Jiang ◽  
Xuesong Xu ◽  
Lu Lin ◽  
Huiyao Wang ◽  
Randall Shaw ◽  
...  

This study investigated the effects of an electromagnetic field (EMF) on control of membrane fouling and scaling during desalination of brackish groundwater using a pilot reverse osmosis (RO) skid. The groundwater was primarily CaSO4 type with a total dissolved solids concentration of 5850 mg/L and hardness of 2500 mg/L as CaCO3. Two EMF devices were installed in the pipeline before a cartridge filter and in the RO feed inlet to induce an electric signal of ±150 kHz to the groundwater. The effects of EMF on membrane scaling were evaluated under accelerated conditions, i.e., without pH adjustment and addition of antiscalant. Two-phase experiments were conducted: Phase 1 (376 h) with the EMF devices turned on after 150 h baseline operation; and Phase 2 (753 h) with the EMF devices turned on from the beginning of testing. The EMF significantly reduced membrane scaling and improved RO performance by 38.3% and 14.3% in terms of normalized water permeability decline rate after 150 h and 370 h operation, respectively. Membrane autopsy results indicated that the fouling layer formed under the influence of EMF was loose with a low density and was easily removed by hydraulic flushing.

Desalination ◽  
2016 ◽  
Vol 395 ◽  
pp. 41-45 ◽  
Author(s):  
Mohammad Rouina ◽  
Hamid-Reza Kariminia ◽  
Seyyed Abbas Mousavi ◽  
Eshaq Shahryari

1975 ◽  
Vol 10 (1) ◽  
pp. 101-109
Author(s):  
H. Kirk Johnston ◽  
H.S. Lim

Abstract The suitability of reverse osmosis as a renovation technique for the treatment of municipal wastewaters has been assessed. Cellulose acetate membranes capable of 70% and 90% NaCl rejections were employed in both laboratory and pilot plant studies to evaluate the efficiency of this technique in removing the residual precipitant chemicals generally employed in phosphorus removal programs (iron chloride, alum, and lime) and the nutrients (phosphates, nitrates and ammonia) characteristic of municipal wastewaters. Secondary sewage and raw sewage as well as prepared nutrient solutions were employed in the course of this program. Both laboratory and pilot plant studies indicated consistently outstanding removal efficiencies for the species examined, almost independent of the nature of the waste solutions being treated. Permeation of the purified effluent was subject to significant reductions due to membrane fouling. This characteristic was most pronounced for the more permeable (less selective) membranes. Routine chemical and physical cleanings enable satisfactory flux levels to be maintained, thereby suggesting that reverse osmosis may become a viable municipal waste treatment technique.


2016 ◽  
Vol 60 (1) ◽  
pp. 46-52 ◽  
Author(s):  
Nalini Gupta ◽  
John Crossley ◽  
Nick Dudding ◽  
John H.F. Smith

Objective: The cytomorphological criteria of malignant endometrial lesions in cervical samples are less well described than those of cervical lesions. We wished to investigate if there were features in SurePath™ liquid-based cytology samples that would facilitate more accurate differentiation between benign and malignant endometrial cells. Study Design: This was a two-phase study, with a review of all SurePath™ samples reported as endometrial adenocarcinoma (n = 42) evaluating 12 cytological features in the first phase. In phase 2 (test set), all initial cases plus an additional 83 cases were reviewed using these 12 cytological features to predict the outcome. Results: Out of 12 cytological features evaluated in phase 1 (training set), nuclear chromatin pattern, apoptotic bodies and tingible body macrophages were found to be the most significant features determining malignant histological outcome. These 12 cytological features were re-evaluated in phase 2 (n = 125). Of 125 cases, 54 had a benign and 71 had a malignant or premalignant histological outcome, with a positive predictive value of 56.8%. Conclusion: Granular nuclear chromatin, tingible body macrophages and apoptosis in the background are the most significant factors in determining whether endometrial cells present in cervical samples represent malignancy or are benign. Using these features, relatively accurate predictions of endometrial pathology can be made.


Blood ◽  
2003 ◽  
Vol 102 (7) ◽  
pp. 2684-2691 ◽  
Author(s):  
Sergio Giralt ◽  
William Bensinger ◽  
Mark Goodman ◽  
Donald Podoloff ◽  
Janet Eary ◽  
...  

Abstract Holmium-166 1, 4, 7, 10-tetraazcyclododecane-1, 4, 7, 10-tetramethylenephosphonate (166Ho-DOTMP) is a radiotherapeutic that localizes specifically to the skeleton and can deliver high-dose radiation to the bone and bone marrow. In patients with multiple myeloma undergoing autologous hematopoietic stem cell transplantation two phase 1/2 dose-escalation studies of high-dose 166Ho-DOTMP plus melphalan were conducted. Patients received a 30 mCi (1.110 Gbq) tracer dose of 166Ho-DOTMP to assess skeletal uptake and to calculate a patient-specific therapeutic dose to deliver a nominal radiation dose of 20, 30, or 40 Gy to the bone marrow. A total of 83 patients received a therapeutic dose of 166Ho-DOTMP followed by autologous hematopoietic stem cell transplantation 6 to 10 days later. Of the patients, 81 had rapid and sustained hematologic recovery, and 2 died from infection before day 60. No grades 3 to 4 nonhematologic toxicities were reported within the first 60 days. There were 27 patients who experienced grades 2 to 3 hemorrhagic cystitis, only 1 of whom had received continuous bladder irrigation. There were 7 patients who experienced complications considered to be caused by severe thrombotic microangiopathy (TMA). No cases of severe TMA were reported in patients receiving in 166Ho-DOMTP doses lower than 30 Gy. Approximately 30% of patients experienced grades 2 to 4 renal toxicity, usually at doses targeting more than 40 Gy to the bone marrow. Complete remission was achieved in 29 (35%) of evaluable patients. With a minimum follow-up of 23 months, the median survival had not been reached and the median event-free survival was 22 months. 166Ho-DOTMP is a promising therapy for patients with multiple myeloma and merits further evaluation. (Blood. 2003;102:2684-2691)


2011 ◽  
Vol 110-116 ◽  
pp. 3997-4003 ◽  
Author(s):  
Jirapat Wanitwattanakosol ◽  
Apichat Sopadang

—In this paper, a conceptual framework to apply many techniques for implementing lean in the high-variety low-volume (HVLV) environment is presented. Lean production has increasingly being implemented as a potential solution for many organizations. Anyway, the lean formula is applicable directly only to the make-to-stock business, but the make-to-order (MTO) product environment has to adapt lean manufacturing principle. The method of this paper has a two-phase quantitative framework to transform small and medium enterprises (SMEs) to be lean. Phase 1 has three interrelated components: (1) re-engineering an organization by using the power of computer simulation combined with business process. (2) Value stream mapping (VSM) is used to create a map of both value and waste in a given process. This tool has also a main drawback for job shop facility because many value streams are composed of hundreds of industrial parts and products. (3) Integrative supplier relationship is one of the most critical factors to maintain an advantage in the increasing levels of competition. Phase 2 performs a just in time production schedule by using ant colony optimization technique combines with a simulation tool. The aims of this paper are to develop a suitable lean manufacturing system for SMEs and to study the performance of the system for improving effectiveness. The result shows how to combine lean concept with simulation optimization, the step of this framework to obtain the optimization solution.


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