My destiny depends on me, depends on me.
I've changed my vocabulary.
From now I'm standing on what I believe.
There is no limit to what I decree.
I know my words,
my words have power, power, power, power!

("My Words Have Power," Karen Clark Sheard, 2015)

 

PTOA Segment 72: Why is this Dude Smiling?

Breeching Area (of a Firebox): The area above the highest row of finned convection tubes and below the stack.

The breeching section funnels the combustion products and flue gases into the stack.

Bridgewall (of a Cabin-style Firebox): The sloped roof that extends from the firebox to the convection section and thereby creates the "cabin looking" firebox structure.

Convection Section (of a Firebox): The area of a firebox above the radiant section; the convection section starts when heat travels in convection waves instead of radiated beams, ergo heat is transferred via convection.

EPA Clean Air Act: One of the United States federal laws that limit how much environmental damage can occur while upgrading feedstocks into consumer products.

The CAA gives direction to the state environmental agencies regarding how much air pollution the industrial complex is allowed to generate and how compliance to the permitted levels is to be achieved.

Compliance to permitted emission levels is a factor Process Operators and Control Board Operators must consider while determining optimal operating conditions.

Finned Convection Tubes (in a Firebox): The tubes in the convection section of a fired heater that are finned for the purpose of increasing the surface area for conduction heat transfer.

Efficient heater designs preheat the process fluid in the finned convection tubes prior to flowing into the radiant section of the firebox.

Radiant Tubes (in a Firebox): The tubes in the firebox that have their external temperature increased by beams of radiated heat from the burners.

Radiant Section (of a Firebox): The lower section of a firebox where heat is transferred to the refractory walls and heater tubes via beams of heat radiating in all directions from the burners.

Shock Bank/Crossover Tubes (in a Firebox): The lowest layer of convection section tubes that are exposed to both radiant heat transfer and convection heat transfer.

Soot: A particulate with an unburned carbon core that is coated with sulfates, nitrates, metals, and toxics.

Soot impairs heat transfer when it settles on the fins of convection section tubes and impairs breathing when released into the atmosphere.

Stack: The chimney of a fired heater/package boiler/reaction furnace which drafts combustion products and flue gases upward and out of the combustion equipment.

Stack Damper: A metal plate located in the stack whose position can be adjusted by Process Operators to establish draft and otherwise control the flow of combustion products and flue gases up and out of the stack.

 

PTOA Segment 73: Not Too Much ... Not Too Little ... Just Right!

Acid Gas: A gas that will cause the generation of acid rain.

In the process industries, the combustion process generates sulfur dioxide (SO₂) and oxides of nitrogen (NO_x), both of which are acid gases.

Acid Rain:  Mild concentrations of sulfuric acid (H₂SO₄) and nitric acid (HNO₃) that are created when acid gases (SO₂ and NO_x) react in the atmosphere with water, oxygen, and other chemicals.

Combustion Products: The desired product of the combustion reaction is radiated heat.

The heat is generated via the "combustion reaction" which burns the reactants of hydrocarbon fuel and oxygen into water vapor (H₂O) and carbon dioxide (CO₂).

Undesirable carbon monoxide (CO) is generated as a byproduct of the combustion reaction when an insufficient amount of oxygen reactant has been supplied for the reaction.

Undesirable oxides of nitrogen and sulfur (acid gases NO_x and SO_x) are formed when the nitrogen component in air and the sulfur component in the hydrocarbon fuel mix with excess oxygen that was not consumed during the generation of heat via the desired combustion reaction.

Completed Combustion Reaction: A combustion reaction that uses hydrocarbon fuel and exactly the right amount of oxygen to generate only heat, carbon dioxide (CO₂), and water vapor (H₂O) and no carbon monoxide (CO), oxides of sulfur (SO_x), or oxides of nitrogen (NO_x).

Completed Combustion Reaction Products: Heat, water vapor, and carbon dioxide (CO₂).

Flue Gases: Gases that are drafted up the stack that include mostly heated but non-reacted nitrogen and oxygen from air (N₂,O₂), and some carbon monoxide (CO), and oxides of nitrogen and sulfur (NO_x,SO_x).

Ground Level Ozone: The bad kind of ozone that does not protect the earth from radiation but rather becomes an air pollutant that causes respiratory problems and aggravates asthma.

Ground level ozone forms when light hydrocarbons, carbon monoxide (CO) and  oxides of nitrogen (NO_x) come into contact with sunlight.

Since the earth needs sunlight, one of the most effective ways to stop the creation of ground level ozone is to stop the amount of light hydrocarbons, carbon monoxide, and nitrogen oxides that are emitted from industrial processes.

Oxides of Nitrogen (NO_x): The "x" in NO_x translates into how many oxygen atoms are chemically bonded to the single Nitrogen atom.

The chemical formula for "Nitric Oxide" is NO; a single atom of Oxygen is bonded to a single atom of Nitrogen.

The chemical formula for "Nitrogen Dioxide" is NO₂; two atoms of Oxygen are bonded to a single atom of Nitrogen.

These two forms of NOx will form when nitrogen and oxygen are heated at high temperatures, which exactly describes the environment in a firebox.

Sulfur Dioxide (SO₂): An air pollutant that forms when the sulfur contained in combusted hydrocarbon fuels combines with excess oxygen while both of these reactants are in a hot environment ... like a fired heater!

SO₂ is an acid gas that will form acid rain and also contributes to the formation of ground level ozone.

Smog: A form of air pollution that initiates respiratory problems in the youngest and oldest human beings and exacerbates pre-existing problems of emphysema, bronchitis, or asthma in all humans.

Smog includes ground level ozone that is generated via reacting NO_x, SO_x, CO, and light hydrocarbons with sunlight.

The photo to the right shows smog blanketing the Bird's Nest Stadium that was built for the 2008 Beijing Summer Olympics.

 

©2015 PTOA Segment 00092
PTOA Process Industry Jargon Recap 3-4

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