Common Process Utilities:

(Thermodynamics-II Lab)

Submitted to:

Dr. Shah Muhammad

Submitted By:

Muhammad Usman (2008-Chem-02-B)

Date: 11February, 2011

Department of Chemical Engineering

University of Engineering & Technology, Lahore

Pipe color code: Blue

1. Compressed air:

Compressed air is supplied in industrial sites for two main uses.

1. Plant air: For general use2. Instrument air: for control systems

Both of these duties require pressurized air at typically at 6-7 bars. Plant air does not always need to be dried, but it is always filtered to prevent dust contaminating tools using it.

Instrument air is dried to prevent condensation and water gathering in the distribution systems and control mechanisms.

Often for convenience, plant air and instrument air with suitable treatment share the same Compressor.

The instrument air should be free from solids, oil, noxious gases and any corrosive materials. The solids contents should be less than 0.1 gm/Nm3with particle sizes less than 3µm.

2. Inert gases:

Several industrial gases are used as general utility for inerting purposes. The main inert gas used in industry is Nitrogen, but Argon & Carbon-Dioxide are also used. Other inert gases include helium, Krypton, Xenon and Neon but they have very specialized applications.

Inert gases are used for Purging and Blanketing. Purging is done to exclude air prior to start up, or to drive out hydrocarbons on shutdown etc.

3. Fuel:

It can be solid (coal etc), Liquid (Oils), and Gaseous Fuels (Natural Gas).

4. Water:

Water is the most widely used process utilities. Almost all plants use water in some form. Water is classified into different uses based on the type & amount of impurities present in it.

1. Process water: Water used by industries to produce a product or affect a process is known as process water.

2. Potable water: Potable water is the drinking water. It contains the impurities that are safe for human health.

3. Cooling water: Water at low temperature used to remove heat from process equipments like coolers etc.

4. hot water:

Pipe color code: Nitrogen/inert gas: light blue +

yellowCO2: Black

Pipe color code : Yellow + white

Water at high temperature used to heat within process systems is known as hot water.

5. Fire water: Water used for extinguishing fire in emergency fire lines in known as fire water.

6. Boiler feed water: It has fewer amounts of impurities that can cause corrosion within Boiler vessel and equipments using that water. Some special compounds are also added into it in order to get specific properties e.g. Anti-Foaming Agents

7. Waste water: It contains a lot of impurities and effluents.

5. Steam: 1. Low pressure steam

2. High pressure steam

3. Exhaust steam

6. Electricity:

It may be purchased or self generated.

7. Natural gas

8. Manufactured gas

9. Refrigerants:

Refrigerants are used to lower the temperature below ambient

within the process. Common refrigerants are chloro floro carbons, air and Methane.

Pipe color code:Cooling water return: light green + dark greenCooling water supply: Dark green + light greenProcess water: Black + BlueUtility water: Dark green + WhitePotable water: Blue + whiteFire water: red Waste water: Green + BlackRaw water: Green

Pipe color code: Silver

Pipe color code: Red

Pipe color code: Yellow

Pipe color code: Blue

10.Thermal Fluids:

Steam is commonly used for heating purposes but at very high temperatures and pressures heating with

Steam becomes un-economical & hence other fluids are needed that can heat the process fluids without

any appreciable change in properties & decomposition.

Commonly used thermal fluids are

1. Dow-Therm

2. Syl-Therm

3. Dow-Frost

4. Dow-cal Pipe color code: Red