When you're drowning you don't think, 'I would be incredibly pleased if someone would notice I'm drowning and come and rescue me.' You just scream.” (the Great Poet John Lennon)

 

THE HEEBIE JEEBIE BLUES

Blow Down Line: The pipe that removes a small portion of recycled fluid from a circulating system for the purpose of preventing the build up of Heebie-Jeebies.

Where the disposed Heebie Jeebies go depends upon the system.

Liquid fluids that are blown into sewer become part of waste water treatment and management. Some gaseous bleed off may be sent to the fuel gas system, burned off in a flare, or otherwise incinerated.

Blow Down Valve: The valve that is manually or automatically opened and closed on a routine basis for the purpose of removing Heebie Jeebies from a circulating system.

Drift Losses: A Cooling Water System loss of water inventory caused by water particles getting through the mist eliminator and thence being blown into the sky.

Evaporative/Evaporation Losses: The intentional loss of water in a Cooling Water System due to evaporation of water into water vapor.

Evaporation accounts for 80% of the temperature drop between the hot water entering a Cooling Tower and the cold water that exits it.

PTOA Readers and Students must understand that the above statement DOES NOT MEAN that 80% of the water entering the Cooling Tower is evaporated.

The evaporation of 1% of the water in a Cooling Water System will reduce the temperature of the remaining water by 10 °F (5.6 °C).

Ergo, a Cooling Water System that has 5% Evaporative Losses will decrease the temperature of the remaining water 50 °F.

Heebie Jeebies: The totally non-scientific name Your Mentor uses to identify any and all bad factors that eventually accumulate in a recycling gas or liquid system.

"Heebie Jeebies happen" and must be removed from the system via Blow Down Lines or slip streams.

Make Up and Make Up Lines: Fresh fluids (gas or liquid) that must be restored to a circulating system to make up for the removal of fluids due to blow down and other system losses.

Make Up Lines for circulating gas systems flow into the circulating gas stream at the compressor suction.

Make Up Lines for circulating liquids systems flow into the circulating liquid stream at the pump suction.

 

NATURALLY COOL, MAN!

Counter Flow (of Air and Water): Air flows upward and water flows downward.

The term 'Counter Flow' is also used to describe flow through shell and tube heat exchangers wherein a hot process stream flows from left to right while a cold process stream flows from right to left...or vice versa.

Cross Flow (of Air and Water): Air flows sideways (left to right or right to left) and water flows downward.

Induced (Mechanical) Draft: The flow of air caused by a strategically placed fan pulling air through a piece of process industry equipment.

Cooling towers that use mechanical draft use induction fans.

Fin Fans with induced draft have the fan placed above the encased finned tubes.

Forced (Mechanical) Draft: The flow of air caused by a strategically placed fan pushing air through a piece of process industry equipment.

Fin fans with forced draft have the fan placed below the encased finned tubes.

Hyperbolic Cooling Tower: A Cooling Tower specifically shaped to influence the natural draft of air to cool very large volumes of cooling water.

In lieu of a fan deck, the Hyperbolic Cooling Tower has a structure shaped like a tall hourglass that creates sufficient velocity for expanding hot air to rise up and up and eventually out of the tower.

Mechanical Draft: A way too fancy term that means creating the movement of air by use of a fan.

Depending on the placement of the fan, the flow of air will be pulled into the process equipment (induction fan) or pushed into the process equipment (forced air fan).

Natural Draft: Movement of air caused by convection, not a fan. Convection is caused by the change in density between cold fluids that are more dense and therefore more heavy than hotter fluids.

Otherwise stated, movement of air caused by the fact that hot air expands and rises (because the particles want to get away from each other and are therefore less dense) and cold air groups back together and flows to the bottom (because it is heavier, more dense).

 

NOT WASTED!

(BFW) Economizers: A piece of waste heat recovery equipment that  preheats BFW via having the BFW make several passes through a coil inserted into boiler's stack.

Hot flue gases indirectly heat the BFW and are cooled down prior to exiting the stack.

(Process Stream) Preheaters: Process stream lines that are indirectly heated by flue gases because these process stream lines are intentionally piped to run through the  convection section of a firebox or duct.

The temperature of the flue gases is reduced after their heat is indirectly transferred into the process fluid that flows through the Preheater.

Waste Heat Recovery Equipment: Process Industry Equipment that economically transfers the heat in a process stream that would otherwise be wasted into a process stream or steam generator that needs to be warmer to continue successful processing.

Waste Heat Recovery Systems:  Individual pieces of  Waste Heat Recovery Equipment connected together in a system that simultaneously cools a gas stream via indirectly transferring the heat of the gas stream into a process stream that needs to be heated.

 

WASTE HEAT RECOVERY SYSTEMS 

Process Gas Cooler: The piece of waste heat recovery equipment that indirectly transfers the heat from a once-through (single pass) flowing hot process gas into BFW to generate saturated steam in a WHB.

The Process Gas Cooler functions like a mud drum in a Package Boiler.

Waste Heat Boiler (WHB): A piece of waste heat recovery equipment composed of a Process Gas Cooler, a Steam Drum, and attached pipes that function like risers and downcomers even though none of the equipment may be labelled as stated in this definition.

A WHB generates saturated steam from BFW that is vaporized by the indirect heat transfer from a hot process gas stream.

 

SYN FULL

Reaction Furnace: A piece of process industry equipment that makes Syngas and functionally is a cross between a fired heater and a reactor.

The tubes in the firebox are stuffed with catalyst that converts light hydrocarbons like methane and water (in the form of steam) into Syngas as long as enough heat is supplied for this highly endothermic reaction.

The Reaction Furnace is also one of the three parts of a Steam Reformer.

Syngas: A gas made in a Reaction Furnace that is the first processing step to produce high-purity hydrogen gas or many man-made petrochemicals.

Syngas is a gaseous mixture of hydrogen gas (H2), carbon dioxide (CO2), and carbon monoxide (CO).

 

REFORMED ... NOW WHAT?

Duct: The elongated channel in a Steam Reformer through which flue gases indirectly transfer heat into a variety of waste heat recovery  equipment such as process stream preheaters and steam superheaters.

Steam Reformer: The process industry equipment required to make Syngas and also recover the waste heat from the flue gases that are generated in the process of supplying sufficient heat required for the highly endothermic Syngas-making reactions.

The three components of a Steam Reformer are:

• Reaction Furnace
• Duct
• Stack

_______________________________________

This concludes the Focus Study on Temperature-Decreasing Process Equipment and Temperature-Changing Process Equipment!

Onto the next Focus Study!

HEAT TRANSFER!

©2015 PTOA Segment 00056
PTOA Process Industry Jargon Recap 2-6

You need to login or register to bookmark/favorite this content.