Chemical Process Engineering and Troubleshooting

Generally we think that cooling tower is Heat transfer equipment, but the actual thing is cooling tower is work on mass transfer and result is Heat transfer. As we know Cooling towers are a very important part of many chemical plants. The primary task of a cooling tower is to reject heat into the atmosphere. They represent a relatively inexpensive and dependable means of removing low-grade heat from cooling water. Hot water from heat exchangers is sent to the cooling tower. The water exits the cooling tower and is sent back to the exchangers or to other units for further cooling. Some of the Applications are listed below.. Oil refineries, Petrochemical industries Chemical Industries, Thermal Power plans, HVAC system for cooling buildings... Working Principle: Humidification Operation : This operation is concerned with the interphase transfer of mass and of energy which result when a gas is brought into contact with a pure liquid in which it

as we all know that without utilities plants can not run.. so it is very important to study the utilities used in the chemical plants, mostly in the heat exchanger or any heating and cooling equipment selection of utilities plays important role... So firstly what is Utilities?? Utility is inseparable part of process plant It is not counted directly as a product, which leaves company premises. But ignoring them may have significant effect on overall profit Input and Output from Process Plant Hear some of the utilities are listed .. Steam  Cooling water  Air  Refrigerant  Brine   Hot oil   Hydrogen   Inert gas (Nitrogen, Helium, Argon)  Electricity etc...  Now commonly as a cooling utility we have 2 option available  1. Cooling Water 2. Cooling Air.. So now thing is how to select from this two? so for that comparison is given below.. Cooling Water  Higher Heat Transfer co-efficient compared air. Highest temperature

So many times industries come across problems associated with thermal expansion in Heat Exchanger, and they have to trade off between four aspects of Heat Exchanger Design.. 1. Allowance for Thermal Expansion 2. Efficient Heat transfer 3. Ease of Cleaning 4. Mechanical Robustness  As shown in the figure how floating head exchangers are work.. The tube side flow enters from the bottom of the tube head.  Generally we take cold fluid on Tube side and Hot fluid on Shell side.  Inside the exchanger we have pass partition plate which forces the total  flow only through bottom half of the tubes.  Now if you have noticed that one of the end of heat exhcanger is open. so the question is Why one of the end must be kept open to float? so the reason is Thermal expansion, more preciously the differential rate of thermal expansion between tube and shell. As higher the temp, and heat transfer takes place between shell and tube side fluid there must be chances for Thermal Expans