Polmon Instruments Interview Questions, Process, and Tips

There are several types of heat exchangers including shell and tube, plate and frame, and air-cooled.

• Shell and tube heat exchangers are the most common type and consist of a shell with tubes running through it.

• Plate and frame heat exchangers use thin plates to transfer heat between fluids.

• Air-cooled heat exchangers use air as the cooling medium instead of water or other liquids.

• Other types include double pipe, spiral,

Distillation is a process of separating components of a mixture based on their boiling points.

• The mixture is heated to vaporize the component with the lowest boiling point

• The vapor is then condensed and collected as a separate liquid

• This process is repeated for each component with a higher boiling point

• Examples include the production of ethanol from fermented grains and the purification of water

Carnot's cycle is a theoretical thermodynamic cycle that describes the most efficient heat engine possible.

• It consists of four reversible processes: isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression.

• It operates between two heat reservoirs at different temperatures.

• The efficiency of the cycle is given by the ratio of the temperature difference between the two reservoirs to the ...read more

Refrigeration cycle is a process of removing heat from a space or substance and transferring it to another space or substance.

• The cycle consists of four main components: compressor, condenser, expansion valve, and evaporator.

• The refrigerant is compressed by the compressor and then condensed in the condenser, releasing heat.

• The high-pressure liquid refrigerant then passes through the expansion valve, where it expands an...read more

Distillation is a process of separating components of a mixture based on their boiling points. There are several types of distillation.

• Simple distillation: used for separating components with a large difference in boiling points

• Fractional distillation: used for separating components with closer boiling points

• Steam distillation: used for separating heat-sensitive compounds

• Vacuum distillation: used for separating compone...read more

Enthalpy is the heat content of a system while entropy is the measure of disorder or randomness in a system.

• Enthalpy is a thermodynamic property that describes the amount of heat released or absorbed during a process.

• Entropy is a measure of the degree of randomness or disorder in a system.

• Enthalpy and entropy are related through the Gibbs free energy equation.

• Enthalpy is usually denoted by the symbol H while entropy is...read more

Boiling point is the temperature at which a liquid turns into a gas.

• Boiling point is a physical property of a substance.

• It is the temperature at which the vapor pressure of the liquid equals the atmospheric pressure.

• Water boils at 100°C or 212°F at standard atmospheric pressure.

• Boiling point can be affected by pressure changes.

• Substances with higher boiling points require more energy to boil than those with lower boili

Unit operation refers to a single step in a process, while unit process involves a series of steps to achieve a specific goal.

• Unit operation is a single step in a process, such as filtration or distillation.

• Unit process involves a series of unit operations to achieve a specific goal, such as producing a certain chemical compound.

• Unit process is a more complex and comprehensive process than unit operation.

• Unit operation...read more

Vapor pressure is the pressure exerted by the vapor of a substance in equilibrium with its liquid or solid phase.

• Vapor pressure increases with temperature

• Substances with high vapor pressure evaporate easily

• Vapor pressure is used in distillation and evaporation processes

• Vapor pressure can be measured using a variety of techniques