Treated Timber Cooling Tower

The basic principle is that the constant vaporization of a portion of the liquid in the reboiler produces a two-phase mixture with an average density lower than the liquid being fed to the reboiler. The heavier column of liquid on the reboiler inlet side then pushes the lighter material out of the reboiler causing circulation. […]

The amount and type of dissolved and/or suspended solids in the stream which may deposit on the tube wall.   The susceptibility to thermal decomposition which will form a thermal barrier on the tube walls.   The velocity of the fluid.   The temperature of the fluid   The fouling resistance specified for a particular […]

Typical overall heat transfer coefficients are given below. These “typical” heat transfer coefficients can be used to estimate the performance of a heat exchanger. Typical heat transfer coefficients are normally published as a range of an “all-in” numbers which includes the inside and outside heat transfer coefficients, the...

For heat exchanger sizing purposes, the cooling water inlet temperature is usually taken as the maximum summer temperature. However, the cooling water outlet temperature can be varied. Theoretically there is an optimum cooling water flow rate (and corresponding cooling water outlet temperature) for each exchanger design. Clearly, there is a maximum...

The first step in preparing a heat exchanger design is assembly of the required data. The minimum requirements for basic data are as follows: Process Fluid Design Flow Rates This is normally the maximum flow rate for the process fluid at full flowsheet rates. However, there may be temporary higher rates during start up or […]

The calculations carried out to design heat exchangers are far from exact. In fact Perry’s refers to the design of heat exchangers as being an art as much as a science. These days almost all heat exchanger designs are carried out using software specifically written for the purpose. The most accepted software used for heat […]

  Shell and tube exchangers can be designed for almost any service. All other exchanger types are compared to shell and tube.   Hairpin type exchangers are a good choice when one fluid is at a very high pressure.   Hairpin exchangers are a good choice when there is a large difference in temperature between […]

Air cooled heat exchangers use ambient air for cooling and condensing. They are typically used in locations where there is a shortage of cooling water. Air-cooled heat exchangers are usually used when the heat exchanger outlet temperature is at least 20°F above the maximum expected ambient air temperature. They can be designed for closer approach...