Cooling water systems passes

Cooling Water System. A list of cooling duties will be available at this point so the cost estimate for this system can be factored or estimated based on a similar operating system. For a more definitive estimate based on initial or detailed layout, it is probably best to use a contractor or consultant skilled in these designs. If a cooling tower is involved, the groundwork will already have been set. This basis can be passed along on specification sheets provided in the Appendix to a vendor for quotes. 

In a steam electric power plant, cooling water is utilized to absorb heat that is liberated from the steam when it is condensed to water in the condensers. The cooling water is withdrawn from a water source, passed through the system, and returned directly to the water source. Shock (intermittent) chlorination is employed in many cases to minimize the biofouling of heat transfer surfaces. Continuous chlorination is used only in special situations. Based on 308 data, approximately 65% of the existing steam electric power plants have once-through cooling water systems. 

The tank is initially filled to its 40% level with the pure reactant B at a concentration C o- Cooling water is passed through a cooling coil immersed in the reactor and reactant A is slowly added to the perfectly stirred vessel. Write the equations describing the system. Without solving the equations, try to sketch the profiles of (feed flow rate) and (concentration of A in the reactor), and C g (concentration of B in the reactor) with time. 

The temperature of the cooled water can at best approach the wet-bulb temperature of the air. Practically, the engineer usually designs on the basis that the water will be 8-13°F (4.5-7°C) above the wet-bulb temperature.12 Since this is an open system, and oxygen is picked up with each pass through the system, corrosion and the growth of micro-organisms within the system are facilitated. For this reason, pretreatment of the water is necessaiy. 

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