Safety vent diameter

Based on these studies, certain safety precautions have been suggested. For example, a venting diameter of 2.35-2.85 inch was suggested for an existing ABS copolymerization reactor in case of double... 

The D-cell was the first cell available within this range. It is rated at 2.5 Ah at the lOh rate. It is 61 mm in height and 34 min in diameter. The construction of this cell is similar to that of standard cylindrical nickel-cadmium cells. It is sealed, has a safety vent, makes use of a cylindrical spiral-wound plate design for high energy density and low internal impedance, and can be charged and discharged in any orientation. 

Credit for additional height of the flame center for multiple valve installations may be taken by clustering the safety valve discharge pipes to the atmosphere. The following procedure should be used for determining equivalent diameter and exit velocity to be used in the flame center calculation. Diameter and velocity are based on the total acmal area of the clustered vents. 

Gas-Fired water heaters are also made more efficient by a variety of designs that increase the recov-ei y efficiency. These can be better flue baffles multiple, smaller-diameter flues submerged combustion chambers and improved combustion chamber geometry. All of these methods increase the heat transfer from the flame and flue gases to the water in the tank. Because natural draft systems rely on the buoyancy of combustion products, there is a limit to the recovery efficiency. If too much heat is removed from the flue gases, the water heater won t vent properly. Another problem, if the flue gases are too cool, is that the water vapor in the combustion products will condense in the venting system. This will lead to corrosion in the chimney and possible safety problems. 

Flares are an attempt to deliberately burn the flammable safety relief and/or process vents from a plant. The height of the stack is important to the safety of the surroundings and personnel, and the diameter is important to provide sufficient flow velocity to allow the vapors/ gases to leave the top of the stack at sufficient velocities to pro ide good mixing and dilution after ignition at the flare tip by pilot flames. 

C and the reaction considered fast at this temperature. Nevertheless, for the safety analysis, an accumulation of 10% is considered realistic. The industrial charge is 4000 kg of final reaction mass in a 4 m3 glass-lined reactor. This vessel is protected against overpressure by a safety valve with a set pressure of 0.3 bar g. The total empty volume of the vessel is 5.5 m3. The vent line has an internal diameter of 50mm and the maximum allowed working pressure of the reactor is 0.3 bar (g). 

A safety factor is, therefore, usually applied to the calculated vent area, the calculated vent area being multiplied by the safety factor which ranges between 1 and 2. The choice of the safety factor depends on the individual situation. A figure of 2 is often used due to uncertainties in the two-phase flow calculations. As a minimum, the calculated vent discharge pipe diameter should be increased to the next available standard pipe size and never reduced. 

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