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This research investigated a novel electrochemical process for producing a ferric iron coagulant for use in treating flowback and produced water from hydraulic fracturing and oil production operations. The electrolytic coagulant generation system uses an electrochemical cell to produce acid and base from oilfield brine solutions. The acid is used to dissolve scrap iron to provide a Fe 3+ coagulating agent, and the base is used to neutralize the treated water. The costs for generating the ferric iron coagulant were determined as a function of current density and feed water salinity. The process was shown to be effective for removing colloidal bentonite particles from brine solutions. The process has several advantages over conventional electrocoagulation using iron anodes, including: the ability to treat anoxic waters, elimination of electrode fouling, lower cost for the coagulant, and the ability to deliver Fe 3+ doses greater than 1 mM, since it is not limited by the amount of dissolved oxygen required to oxidize ferrous to ferric iron.

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The primary goal of this research was to investigate several water treatment unit operations for converting RO concentrate produced from treated municipal wastewater into potable water. The secondary goal was to evaluate the use of an electrochemical cell for producing the reagents needed to operate a fluidized bed crystallization reactor (FBCR), regenerate ion exchange media, and produce a ferric iron coagulating agent. The effectiveness of the pretreatment processes to prevent membrane fouling were evaluated for conventional and high-efficiency reverse osmosis (HERO). Fluidized bed crystallization removed 93 to >97% of hardness ions, 42% of silica, and 6.5% of total organic carbon. Membrane fouling during HERO was lower than that for conventional RO for pretreatment using fluidized bed crystallization and ion exchange. However, conventional RO with ferric iron coagulation following fluidized bed crystallization and ion exchange showed the least membrane fouling and increased recovery in the second stage RO by 470%. The use of an electrochemical cell for generating the reagents needed for the pretreatment processes was evaluated. Energy costs for operating the electrochemical cell for making acid, base, and ferric iron coagulant were 4.1 kWh per m3 of RO concentrate. The use of electrochemically generated reagents combined with fluidized bed crystallization produces no waste solutions from the pretreatment processes.

Background: Hepatic cirrhosis is an important cause of morbidity and mortality in the intensive care unit (ICU). Objective: To determine the precipitating factors, presenting complaints, course of the disease and predictors of mortality in patients with liver cirrhosis admitted to the ICU. Methods: This retrospective study was conducted mat Multidisciplinary ICU at tertiary care hospital from April 2013 to March 2014. A total of 107 patients diagnosed with liver cirrhosis were admitted to the ICU. Of these, 17 were discharged against medical advice. The remaining 90 patients were included in the study. Their case notes were examined for data such as severity of disease, precipitating events and their course in the ICU. The survivors were followed up telephonically to assess survival at six months. Results: There were 30 survivors and 60 nonsurvivors. The stage of cirrhosis (based on modified Child-Pugh criteria) had significant association with hospital mortality and disease outcome. Mortality was significantly higher in patients presenting with sepsis and septic shock (P=0.022) and hepatic encephalopathy (P=0.007). Interventions such as mechanical ventilatory support (P=0.002), inotropes (P=0.001) and vasopressors (P=0.048), variceal banding (P=0.005), need for transfusion of fresh frozen plasma (P=0.001) and packed cell transfusion (P=0.036) showed significant association with clinical outcome. Conclusion: Overall mortality rate of patients admitted in the ICU with liver cirrhosis is high (66.7%). Mortality rate is higher in those with Stage C cirrhosis, sepsis and septic shock and hepatic failure. Among the patients who survive, one third may not survive beyond six months after hospital discharge.