The production of hazardous gases such as CO2 and H2S impose high risks to offshore operations, with lethal impacts on personnel, along with special equipment required and environmental challenges. Hydrocarbon productions require that part of this gas could disperse on the atmosphere, so a comprehensive risk analysis is necessary to evaluate the gas disposal event. Computational Fluid Dynamic (CFD) can be used to effective study how the wind and environment can interfere with the gas dissipation in the air. In this work, a specific analysis was necessary to produce a gas well with up to 80% CO2 fluid composition. A CFD Gas Dispersion Analysis evaluated the turbulent airflow over and offshore drilling vessel perimeter to map the flammability levels and hazardous gases concentration zones, depending on winds speeds, wind directions, and well gas flowrates. Parallel processing was applied in order to reduce the computing time for simulation of 52 cases on gas release on burner booms and relief lines, and 56 cases for leak analysis on the process plant. The results permitted defining using 3D maps the concentration levels of hazardous gases on the rig expected on each scenario condition, as well as the coverage area outside the vessel affected by the gas release.

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exercise in participants, heterogeneity of exercise, and the small number of studies included.In 2017, a meta-analysis including 21 RCTs (N55,540) focused on exercise interventions for fall reduction. 3 The trials included nursing home adults (65 years old and older, mean age 82.6 years old, 81% female). Interventions included exercise alone (strength, balance, endurance, or walking) or exercise combined with two or more other interventions including medication review, education, home visit, environmental modification, or staff education. The intervention duration was between 4 and 48 weeks. Outcome measures included the rates of falls and number of fallers and were assessed by nursing home staff or medical records. Overall, exercise interventions reduced the rate of falls (18 trials, N55,047; RR 0.81; 95% CI, 0.68-0.97). Exercise combined with other interventions also resulted in a significant decrease in the rate of falls (14 trials, N54,100; RR 0.6; 95% CI, 0.52-0.72) and the number of fallers (14 trials, N54,100; RR 0.85; 95% CI, 0.77-0.95). Compared with control group interventions, all exercise interventions and exercise alone did not reduce the number of fallers, and exercise alone did not reduce the rate of falls. Limitations were similar to the previous study.

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Hydrate formation in production and control lines has been a serious issue in the oil industry, especially in the deepwater offshore market. This article focuses on a compact temporary plant designed to be assembled on offshore rigs for heating and injecting high flow rate water to break hydrates. Hydrates are formed under determined conditions (high pressure at low temperature) in which natural gas hydrocarbon molecules are trapped in ice molecules, forming crystal structures and plugging or choking lines, causing operational problems. When preventive solutions, such as chemical inhibitors or thermal insulation, do not work, the formed hydrate must be broken or dissociated to set the lines free. One option is active heating, in which hot fluid is circulated to increase the temperature and break the hydrate ice structures. Consequently, a compact plant, with combined direct and indirect heating, was designed to deliver a customized solution for an offshore rig. Drill or salt water pumps were used to supply cold water at 12 bpm at 25 °C, and two steam generators were used to inject steam into the flow, mixing inline and delivering water at 49 °C at the mud tanks. This tank water was pumped through mud pumps at 12 bpm, passing through four steam heat exchangers (SHE) to deliver water at a final temperature of 90 °C. The total process used six steam generators and four SHE to heat water from 25 to 90 °C at 12 bpm. The compact design for the high flow rate injection plant was only possible with combined and independent processes. Direct heating by steam injection was used inline downstream from the drill water pump to preheat the water to 49 °C while feeding the mud tank. Indirect heating used four SHE downstream of the mud pump to deliver water at 90 °C at the seabed.