cpi industrial gases

8/6/2019 CPI Industrial Gases

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Industrial GasesSome common industrial gases; their uses and applications

Group Head: Zubair Ahmed (CH-015)

Submitted to: Sir Asim

Course: CPI

Other group members:

o Noman (CH-008)

o Muhaamad Ali (CH-010)o Javaid (CH-012)o Ismail Khan (CH-017)

o Umain Aziz (CH-021)

o Asad (CH-053)

o Javaid Nawaz (CH-054)

o Numan Hussain (CH-060)o Noor Muhammad (CH-068)

o Munned Ali Mirza (CH-069)

o Arsalan (CH-0)


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Industrial gases:

Industrial gas is a group of gases that are commercially manufactured and sold for uses in other

applications. These gases are mainly used in an industrial processes, such as steelmaking, medical

applications, fertilizer, semiconductors, etc,. They may be both organic and inorganic, are produced by

extraction from the air by a process of separation or are produced by chemical synthesis, and will takevarious forms such as compressed, liquid, or solid.

Common industrial gases:

This list shows the most common gases sold by industrial gas companies. Many gas mixtures are also sold.

Important liquefied gases:

This list shows the most important liquefied gases.

liquid nitrogenliquid oxygen

liquid argon

liquid hydrogenliquid helium

LNGLiquefied petroleum gas

Industrial Gases Are Valued for Their Physical and Chemical Properties:Industrial gases are valued for one or more of the following properties:

Reactivity Inertness Coldness

These properties are utilized to produce specialty products, protect and maintain product quality, and

lower operating costs in steelmaking, metals manufacturing and fabrication, petroleum refining, chemicals

Air

Air gases -

bulk gasesproduced

from an

. AirSeparation

Unit

nitrogen (N2)oxygen (O2)

Noble gases

helium (He)

argon (Ar)krypton (Kr)

neon (Ne)

xenon (Xe)

Compound gases

ammonia (NH3)

carbon dioxide (CO2)carbon monoxide (CO)

hydrogen chloride

(HCl)nitrous oxide (N2O)

nitrogen trifluoride(NF3)

sulfur dioxide (SO2)sulfur hexafluoride

(SF6)

Hydrocarbon gases

methane (CH4)

acetylene (C2H2)ethane (C2H6)ethene (C2H4)

propane (C3H8)propene (C3H6)

butane (C4H10)butene (C4H8)

other

Elemental

gases

hydrogen(H2)

chlorine(Cl2)

fluorine

(F2)


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and pharmaceuticals manufacture, production of electronic equipment and components, the rubber and

plastics industries, food and beverage processing, glass manufacture, healthcare, pulp and paper and

environmental protection operations.

Gases Valued for Reactivity:

Oxygen (O2), in particular, is valued for its reactivity. Oxygen enrichment of air is used to increase the

amount of oxygen available for combustion or biological activity. This can increase reaction rates and lead

to greater throughput in existing equipment and smaller sizes for new equipment.

Another benefit of oxygen enrichment is a reduction in the amount of nitrogen and other gases passing

through a furnace or process. This results in less energy consumption, reduced environmental impact, and

reduced equipment size.

Oxygens reactivity is used in metals processing (steel, copper, lead, zinc), glass furnaces, cement kilns,

chemical manufacture, sewage treatment, pulp and paper manufacture, welding and cutting of metals,

and medical oxygen.

Hydrogen (H2), methane (CH4), and carbon monoxide (CO) are gases that react with oxygen and other

materials. These gases are often used as raw materials for chemical manufacturing processes.

Hydrogen is used in refineries to remove sulfur and to chemically restructure (reform) hydrocarbons. It isused to hydrogenate unstable, unsaturated hydrocarbons and fatty acids in animal and vegetable oils. It is

also used as a reducing agent in steel and zinc manufacture removing oxygen that would react with and

degrade the product.

Methane (CH4), generated by biological activity, is the primary component of natural gas. It is used as

a fuel and as a chemical raw material.

Carbon monoxide (CO) is co-produced with hydrogen by steam reforming plants using methane or other

hydrocarbons as feedstock. It is a raw material for making monomers and other chemical products.

Carbon Dioxide (CO2) does not react with oxygen, but will combine with other elements and compounds.

Thus its commercial uses include raw material for various chemical processes and neutralizing agent for

alkaline materials.

Gases Valued for Inertness:

Inertness is somewhat relative. Some industrial gases (helium, neon, argon, krypton and xenon) are

almost totally inert. Helium and argon are commercially available in relatively large quantities, neon,

krypton and xenon have much more limited availability. Many applications requiring an "inert gas" rely on

nitrogen or carbon dioxide, because they have very little reactivity under normal pressure and

temperature conditions and are much less expensive than the other "inert" gases. The naturally inert or

"noble" gases are members of "Group 18" of the Periodic Table. They have their outermost, or valence,

electron shell complete (with two electrons for helium and eight for the other gases). The "noble" gases

are all monatomic.

Nitrogen (N2) and Argon (Ar) are commonly used in the gaseous form to shield potentially reactive

materials from contact with oxygen. Nitrogen will react with oxygen at very high temperatures, as in

furnaces, but it is inert under most other circumstances. Argon, helium, neon, krypton and xenon are

"noble gases" that are extremely inert under all conditions.

Carbon Dioxide (CO2) is also used in some applications for its inertness, in particular for fire fighting. Both

portable fire extinguishers and total room fire extinguisher systems use carbon dioxide to extinguish

flames without damage to materials and without the risk of short circuiting electrical systems or damaging

electronic components.


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Applications based on inertness include blanketing of storage tanks and vessels that contain flammable

liquids or powders; blanketing of materials that would degrade in air, such as vegetable oil, spices, and

fragrances; maintaining controlled atmospheres for industrial activities such as growing silicon and

germanium crystals, manufacturing precision electronic devices, welding and soldering; preventing light

bulb filaments from burning; retarding evaporation of filaments with high molecular weight inert gases;

sparging (bubbling gas through liquids) to reduce the amount of oxygen or other gases dissolved in a

liquid; filling insulating spaces between multi-pane windows; and creating non-flammable lighter-than-air

devices such as balloons and dirigibles (using helium instead of hydrogen).

Liquefied Gases Valued as a Source of Intense Cold:

Liquid Nitrogen (LIN, LN) and Liquid Carbon Dioxide (LCO2) are valued because they combine intense

coldness with inertness. This combination is employed to rapidly chill and freeze food items (meat, fruit,

vegetables, baked goods, and dairy products). Rapid freezing results in very small ice crystals, less cellular

damage, and better-quality products after thawing.

The intense cold produced by these products can also be used to make normally soft and flexible materials

hard and rigid, allowing them to be ground, machined or fractured.

Applications and Uses of Common Industrial Gases:

Some of the most common industrial gases are listed below:

Oxygen Nitrogen Argon Neon, Krypton, Xenon Carbon Dioxide Hydrogen

OXYGEN (O2):

Multi-Industry Uses for Oxygen:

Oxygen is used with fuel gases in gas welding, gas cutting, oxygen scarfing, flame cleaning, flame

hardening, and flame straightening.

In gas cutting, the oxygen must be of high quality to ensure a high cutting speed and a clean cut.

Metals Manufacturing Uses for Oxygen:

The largest user of oxygen is the steel industry. Modern steelmaking relies heavily on the use of

oxygen to enrich air and increase combustion temperatures in blast furnaces and open hearth furnaces

as well as to replace coke with other combustible materials. During the steel making process,unwanted carbon combines with oxygen to form carbon oxides, which leave as gases. Oxygen is fed

into the steel bath through a special lance. Oxygen is used to allow greater use of scrap metal in

electric arc furnaces. Large quantities of oxygen are also used to make other metals, such as copper,

lead, and zinc.

Oxygen enrichment of combustion air, or oxygen injection through lances, is used to an increasing

extent in cupola furnaces, open-hearth furnaces, smelters for glass and mineral wool, and lime and

cement kilns, to enhance their capacity and reduce energy requirements. Smelting times and energy


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consumption can also be reduced by special oxy-oil or oxy-gas burners in electro-steel furnaces and

induction smelters for aluminum. A high thermal efficiency is achieved by these oxy-fuel burners,

which mix fuel and oxygen at the tip of the burner. As a result, rapid combustion occurs at

approximately 2800o

C (5072oF).

Chemicals, Pharmaceuticals and Petroleum Uses:

Oxygen is used as a raw material in many oxidation processes, including the manufacture of ethylene

oxide, propylene oxide, synthesis gas using partial oxidation of a wide range of hydrocarbons, ethylene

dichloride, hydrogen peroxide, nitric acid, vinyl chloride and phthalic acid.

Very large quantities of oxygen are used in coal gasification to generate a synthesis gas that can be

used as a chemical feedstock or precursor for more easily- transported and easily-used fuels.

Oxygen is used to enrich the air feed to catalytic cracking regenerators, which increases capacity of the

units. It is used in sulfur recovery units to achieve similar benefits. Oxygen is also used to regenerate

catalysts in refineries.

Oxygen is used to achieve more complete combustion and destruction of hazardous and waste

materials in incinerators.

Glass and Ceramics Industry Uses:

Conversion of combustion systems from air-fuel to oxy-fuel (and construction of new furnaces and

tanks around this technology) results in better control of heating patterns, higher furnace efficiencies

(lower fuel consumption) and reduction in particulate and NOx emissions.

Pulp and Paper Manufacturing Uses:

Oxygen is increasingly important as a bleaching chemical. In the manufacture of high-quality bleached

pulp, the lignin in the pulp must be removed in a bleaching process. Chlorine has been used for this

purpose but new processes using oxygen reduce water pollution. Oxygen plus caustic soda can replacehypochlorite and chlorine dioxide in the bleaching process, resulting in lower costs.

In a chemical pulp mill, oxygen added to the combustion air increases the production capacity of the

soda recovery boiler and the lime-reburning kiln. The use of oxygen in black liquor oxidation reduces

the discharge of sulfur pollutants into the atmosphere.

Health Care Uses:

In medicine, oxygen is used during surgery, intensive care treatment, inhalation therapy, etc. High

standards of purity and handling must be maintained.

Oxygen is typically supplied to hospitals though bulk liquid deliveries, then distributed to usage points.

It assists with respiratory problems, saving lives and increasing patient comfort.

Small portable air separation units are gaining wide use in home care. Larger scale units using which

also use non-cryogenic air separation technology, are being utilized in small and/or remote hospitals

where demand is high enough to make cylinder deliveries a logistical problem but where liquid

deliveries are unavailable or very costly. These units typically producing 90 to 93% purity oxygen, which

is adequate for most medical uses.

Environmental:


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In the biological treatment of waste-water, the use of oxygen instead of air permits increased capacity

in existing treatment plants. Injecting oxygen into sewers reduces hydrogen sulfide formation, which

results in reduced corrosion and odor.

Ozone is used for drinking water treatment, in particular when alternatives, such as chlorine, are

undesirable.

Miscellaneous Uses for Oxygen:

Oxygen has many uses in breathing apparatus, such as those for underwater work and refinery and

chemical plant self contained breathing apparatus.

Aquaculture, the cultivation of fish in ponds uses oxygenated water to allow ensure sufficient oxygen is

always present and to allow more fish to be raised or kept in a given size of pond or tank.

Liquid oxygen is used in liquid-fueled rockets as the oxidizer for fuels such as hydrogen and liquid

methane.

Interesting Facts and Information about Oxygen (O2):

y Oxygen (O2) is an active, life-sustaining component of the atmosphere; making up 20.94% by

volume or 23% by weight of the air we breathe. It is colorless, odorless and tasteless. Oxygen is

the most widely occurring element on Earth. Because it forms compounds with virtually all

chemical elements except the noble gases, most terrestrial oxygen is bound with other elements

in compounds such as silicates, oxides, and water. Oxygen is also dissolved in rivers, lakes, and

oceans. Molecular oxygen occurs almost entirely in the atmosphere.

y Oxygen is highly oxidizing (a general chemical term applying to any substance, like oxygen, that

accepts electrons from another substance during reaction). Oxygen reacts vigorously with

combustible materials, especially in its pure state, releasing heat in the reaction process. Many

reactions require the presence of water or are accelerated by a catalyst.

y Ozone (O3) is an allotropic form of oxygen that is more reactive than ordinary oxygen. Ozone is

formed in nature by electrical discharges or by irradiation with ultraviolet light. Commercial ozone

generators mimic these natural process to make large amounts for industrial and environmental

treatment processes or add a small amount of ozone to breathing air for its invigorating effect and

"fresh air" scent.

y Oxygen has a low boiling/ condensing point: -297.3F (-183C). The gas is approximately 1.1 times

heavier than air and is slightly soluble in water and alcohol. Below its boiling point, oxygen is a

pale blue liquid slightly heavier than water.

y Oxygen is the second-largest volume industrial gas. Aside from its chemical name O2, oxygen may

be referred to as GOX or GO when produced and delivered in gaseous form, or as LOX or LO when

in its cryogenic liquid form.

y Oxygen is produced in large quantities and at high purity as a gas or liquid by cryogenic

distillation and as a lower purity gas (typically about 93%) by adsorption technologies (pressure


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swing adsorption, abbreviated as PSA, or vacuum-pressure swing adsorption, abbreviated as VPSA

or more simply, VSA).

y Oxygen is valued for its reactivity. Oxygen is commonly used, with or instead of air, to increasethe amount of oxygen available for combustion or biological activity. This increases reaction rates

and leads to greater throughput in existing equipment and smaller sizes for new equipment.

y Oxygen has numerous uses in steelmaking and other metals refining and fabrication processes,

in chemicals, pharmaceuticals, petroleum processing, glass and ceramic manufacture, and pulp

and paper manufacture. It is used for environmental protection in municipal and industrial

effluent treatment plants and facilities. Oxygen has numerous uses in healthcare, both in

hospitals, outpatient treatment centers and home use. For some uses, such as effluent treatment

and pulp and paper bleaching, oxygen is converted to ozone (O3), an even more reactive form, to

enhance the rate of reaction and to ensure the fullest possible oxidation of undesired

compounds.

Nitrogen (N2):Multi-Industry Uses for Nitrogen:

The inert properties of nitrogen make it a good blanketing gas in many applications. Nitrogen blanketing is

used to protect flammable or explosive solids and liquids from contact with air. Certain chemicals, surfaces

of solids, and stored food products have properties that must be protected from degradation by the

effects of atmospheric oxygen and moisture. Protection is achieved by keeping these items in (under) a

nitrogen atmosphere. "Inerting" or "padding" are other terms used to describe displacement of air and

nitrogen blanketing.

"Sparging" with nitrogen is the bubbling of nitrogen gas through a liquid to remove unwanted volatile

components, including volatile organic compounds (VOC) which may be necessary to meet pollution

reduction regulations.Certain substances are difficult to pulverize or shred because they are tough or the materials will be

degraded by the heat generated by mechanical processes such as grinding. Liquid nitrogen can be used to

freeze soft or tough substances prior to their entering a size reduction process. Cold vaporized nitrogen

can be used to keep materials cool (and in an inert atmosphere) during grinding. Cryogenic grinding is

used in diverse applications, including production of finely ground pharmaceuticals, plastics and pigments;

and for shredding tires in recycling plants.

Metals Manufacturing Uses for Nitrogen:

Nitrogen is used to treat the melt in the manufacture of steel and other metals and as a shield gas in the

heat treatment of iron, steel and other metals. It is also used as a process gas, together with other gasesfor reduction of carbonization and nitriding.

Flash or fins on cast metal can be removed by cooling with liquid nitrogen, making them brittle,

allowing then to be broken off by mechanical action.

Manufacturing and Construction Uses:


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Nitrogen (and nitrogen mixed with CO2 and oxygen) is used in transport trucks and in Modified

Atmosphere Packaging (MAP) to extend the shelf life of packaged foods by preventing oxidation, mold,

insect infestation and moisture migration.

Health Care Uses:

Nitrogen is used as a shield gas in the packing of some medicines to prevent degradation by oxidation or

moisture adsorption.

Nitrogen is used to freeze blood, as well as viruses for vaccination. It is also used to freeze livestock

semen, which can then be stored for years. The quick freezing resulting from the intense cold minimizes

cell wall damage. Liquid nitrogen is also used in some MRI (Magnetic Resonance Imaging) devices to pre-

cool the low temperature magnets prior to using much more expensive liquid helium for final cooling.

Liquid nitrogen is used in cryo-surgery to destroy diseased tissue.

Miscellaneous Uses for Nitrogen:

Nitrogen is used directly as a coolant for severe environmental testing of many items, or as a refrigeration

source for chilling circulating dry air.

Interesting Facts and Information about Nitrogen (N2):

y Nitrogen (N2) is a colorless, odorless and tasteless gas that makes up 78.09% (by volume) of the

air we breathe. It is nonflammable and it will not support combustion.

y Nitrogen gas is slightly lighter than air and slightly soluble in water. It is commonly thought of and

used as an inert gas; but it is not truly inert. It forms nitric oxide and nitrogen dioxide with

oxygen, ammonia with hydrogen, and nitrogen sulfide with sulfur. Nitrogen compounds are

formed naturally through biological activity. Compounds are also formed at high temperature orat moderate temperature with the aid of catalysts. At high temperatures, nitrogen will combine

with active metals, such as lithium, magnesium and titanium to form nitrides. Nitrogen is

necessary for various biological processes, and is used as a fertilizer, usually in the form of

ammonia or ammonia-based compounds. Compounds formed with halogens and certain organic

compounds can be explosive.

y Nitrogen condenses at its boiling point, -195.8o C (-320.4o F), to a colorless liquid that is lighter

than water.

y More nitrogen is used by customers than any other industrial gas. It is used in a broad range of

industries, including chemicals, pharmaceuticals, petroleum processing, glass and ceramic

manufacture, steelmaking and other metals refining and fabrication processes, pulp and paper

manufacture, and healthcare. Aside from N2, nitrogen may be referred to as GAN or GN in its

gaseous form, and LIN or LN in its liquid form.

y Nitrogen is produced in large volumes in both gas and liquid form by cryogenic distillation; smaller

volumes may be produced as a gas by pressure swing adsorption (PSA) or diffusion separation

processes (permeation through specially designed hollow fibers). Cryogenic processes can

produce very pure nitrogen. Adsorption and diffusion processes are typically used to make lower

purity product in relatively small amounts. This is attractive to users when purity is not critical and


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alternatives (purchase of bulk liquid nitrogen, cylinders of high pressure nitrogen, or local

cryogenic production) are more expensive or impractical.

y Gaseous nitrogen is valued for inertness. It is used to shield potentially reactive materials from

contact with oxygen.

y Liquid nitrogen is valued for coldness as well as inertness. When liquid nitrogen is vaporized and

warmed to ambient temperature, it absorbs a large quantity of heat. The combination of

inertness and its intensely cold initial state makes liquid nitrogen an ideal coolant for certain

applications such as food freezing. Liquid nitrogen is also used to cool materials which are heat

sensitive or normally soft to allow machining or fracturing. Examples are used tires, plastics,

certain metals and even pharmaceuticals.

Carbon Dioxide (CO2):

Multi-Industry Uses for Carbon Dioxide (CO2):

Carbon dioxide in solid and in liquid form is used for refrigeration and cooling. It is used as an inert gas in

chemical processes, in the storage of carbon powder and in fire extinguishers.

Metals Industry:

Carbon dioxide is used in the manufacture of casting molds to enhance their hardness.

Manufacturing and Construction Uses:

Carbon dioxide is used on a large scale as a shield gas in MIG/MAG welding, where the gas protects the

weld puddle against oxidation by the surrounding air. A mixture of argon and carbon dioxide is commonlyused today to achieve a higher welding rate and reduce the need for post weld treatment.

Dry ice pellets are used to replace sandblasting when removing paint from surfaces. It aids in reducing the

cost of disposal and cleanup.

Chemicals, Pharmaceuticals and Petroleum Industry Uses:

Large quantities are used as a raw material in the chemical process industry, especially for methanol and

urea production.

Carbon dioxide is used in oil wells for oil extraction and maintain pressure within a formation.. When CO 2

is pumped into an oil well, it is partially dissolved into the oil, rendering it less viscous, allowing the oil to

be extracted more easily from the bedrock. Considerably more oil can be extracted from through thisprocess.

Rubber and Plastics Industry Uses:

Flash is removed from rubber objects by tumbling them with crushed dry ice in a rotating drum.

Food and Beverages Uses for Carbon Dioxide:


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Liquid or solid carbon dioxide is used for quick freezing, surface freezing, chilling and refrigeration in the

transport of foods. In cryogenic tunnel and spiral freezers, high pressure liquid CO2 is injected through

nozzles that convert it to a mixture of CO2 gas and dry ice "snow" that covers the surface of the food

product. As it sublimates (goes directly from solid to gas states) refrigeration is transferred to the product.

Carbon dioxide gas is used to carbonate soft drinks, beers and wine and to prevent fungal and bacterial

growth.

Liquid carbon dioxide is a good solvent for many organic compounds. It is used to de-caffeinate coffee.

It is used as an inert blanket, as a product-dispensing propellant and an extraction agent. It can also be

used to displace air during canning.

Supercritical CO2 extraction coupled with a fractional separation technique is used by producers of flavors

and fragrances to separate and purify volatile flavor and fragrances concentrates.

Cold sterilization can be carried out with a mixture of 90% carbon dioxide and 10% ethylene oxide, the

carbon dioxide has a stabilizing effect on the ethylene oxide and reduces the risk of explosion.

Health Care Uses:

Carbon dioxide is used as an additive to oxygen for medical use as a respiration stimulant.

Environmental Uses:

Used as a propellant in aerosol cans, it replaces more environmentally troublesome alternatives.

By using dry ice pellets to replace sandblasting when removing paint from surfaces, problems of residue

disposal are greatly reduced.

It is used to neutralize alkaline water.

Miscellaneous Uses for Carbon Dioxide (CO2):

Liquid carbon dioxide's solvent potential has been employed in some dry cleaning equipment as a

substitute for conventional solvents. This use is still experimental - some types of soil are more effectively

removed with traditional dry cleaning equipment, and the equipment is more expensive.

Yields of plant products grown in greenhouses can increase by 20% by enriching the air inside the

greenhouse with carbon dioxide. The target level for enrichment is typically a carbon dioxide

concentration of 1000 PPM (parts per million) - or about two and a half times the level present in the

atmosphere.

Interesting Facts and Information about Carbon Dioxide (CO2):

y Carbon dioxide (CO2) is a slightly toxic, odorless, colorless gas with a slightly pungent, acid taste.

Carbon dioxide is a small but important constituent of air. It is a necessary raw material for most

plants, which remove carbon dioxide from air using the process of photosynthesis.y A typical concentration of CO2 in air is about 0.038% or 380 ppm. The concentration of

atmospheric carbon dioxide rises and falls in a seasonal pattern over a range of about 6 ppmv. The

concentration of CO2 in air has also been steadily increasing from year to year for over 60 years.

The current rate of increase is about 2 ppm per year.


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y Carbon dioxide is formed by combustion and by biological processes. These include decomposition

of organic material, fermentation and digestion. As an example, exhaled air contains as much as

4% carbon dioxide, or about 100 times the amount of carbon dioxide which was breathed in.

y Large quantities of CO2 are produced by lime kilns, which burn limestone (primarily calcium

carbonate) to produce calcium oxide ( lime, used to make cement); and in the production of

magnesium from dolomite (calcium magnesium carbonate). Other industrial activities which

produce large amounts of carbon dioxide are ammonia production and hydrogen production from

natural gas or other hydrocarbon raw materials.

y The concentration of CO2 in air and in stack gases from simple combustion sources (heaters,

boilers, furnaces) is not high enough to make carbon dioxide recovery commercially feasible.

Producing carbon dioxide as a commercial product requires that it be recovered and purified from

a relatively high-volume, CO2-rich gas stream, generally a stream which is created as an

unavoidable byproduct of a large-scale chemical production process or some form of biological

process.

y In almost all cases, carbon dioxide which is captured and purified for commercial applications

would be vented to the atmosphere at the production point if it was not recoved for transport andbeneficial use at other locations.

y The most common operations from which commercially-produced carbon dioxide is recovered are

industrial plants which produce hydrogen or ammonia from natural gas, coal, or other

hydrocarbon feedstock, and large-volume fermentation operations in which plant products are

made into ethanol for human consumption, automotive fuel or industrial use. Breweries

producing beer from various grain products are a traditional source. Corn-to-ethanol plants have

been the most rapidly growing source of feed gas for CO2 recovery.

y CO2-rich natural gas reservoirs found in underground formations found primarily in the western

United States and in Canada are another source of recoverable carbon dioxide. CO2 from bothnatural and industrial sources is used to enhance production of oil from older wells by injecting

the carbon dioxide into appropriate underground formations. Carbon dioxide is used in

selectively, primarily in wells which will benefit not only from re-pressurization, but also from a

reduction in viscosity of the oil in the reservoir caused by a portion of the CO2 dissolving in the oil.

(The extent to which carbon dioxide will dissolve in the oil varies with the type of petroleum

present in the reservoir. If the viscosity reduction effect will be minimal, nitrogen, which is usually

less expensive, may be used as the pressurant instead.)

y Carbon dioxide will not burn or support combustion. Air with a carbon dioxide content of more

than 10% will extinguish an open flame, and, if breathed, can be life-threatening. Such

concentrations may build up in silos, digestion chambers, wells, sewers and the like. Caution must

be exercised when entering these types of confined spaces.

y CO2 gas is 1.5 times as heavy as air, thus if released to the air it will concentrate at low elevations.

Carbon dioxide will form "dry ice" at -78.5C (-109.3 F). One kg of dry ice has the cooling capacity

of 2 kg of ordinary ice. Gaseous or liquid carbon dioxide, stored under pressure, will form dry ice

through an auto-refrigeration process if rapidly depressurized.


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y Carbon dioxide is commercially available as high pressure cylinder gas, relatively low pressure

(about 300 psig or 20 bar) refrigerated liquid, or as dry ice. Large quantities are produced and

consumed at industrial sites making fertilizers, plastics and rubber.

y Carbon dioxide is a versatile material, being used in many processes and applications - each of

which takes advantage of one or more these characteristics: reactivity, inertness and/ or

coldness.

y Carbon dioxide is commonly used as a raw material for production of various chemicals; as aworking material in fire extinguishing systems; for carbonation of soft drinks; for freezing of food

products such as poultry, meats, vegetables and fruit; for chilling of meats prior to grinding; for

refrigeration and maintenance of ideal atmospheric conditions during transportation of food

products to market; for enhancement of oil recovery from oil wells; and for treatment of alkaline

water.

Hydrogen (H2):

Metals:

Hydrogen is mixed with inert gases to obtain a reducing atmosphere, which is required for many

applications in the metallurgical industry, such as heat treating steel and welding. It is often used in

annealing stainless steel alloys, magnetic steel alloys, sintering and copper brazing.

Hydrogen can be produced by dissociation of ammonia at about 1800F with the aid of a catalyst - which

results in a mix of 75% hydrogen and 25% mononuclear nitrogen (N rather than N2). The mix is used as a

protective atmosphere for applications such as brazing or bright annealing.

Chemicals, Pharmaceuticals and Petroleum:

Hydrogen is used in large quantities as a raw material in the chemical synthesis of ammonia, methanol,

hydrogen peroxide, polymers, and solvents.

In refineries, it is used to remove the sulfur that contained in crude oil. Hydrogen is catalytically combined

with various intermediate processing streams and is used, in conjunction with catalytic cracking

operations, to convert heavy and unsaturated compounds to lighter and more stable compounds.

The pharmaceutical industry uses hydrogen to manufacture vitamins and other pharmaceutical products.

Large quantities of hydrogen are used to purify gases (e.g. argon) that contain trace amounts of oxygen,

using catalytic combination of the oxygen and hydrogen followed by removal of the resulting water.

Glass and Ceramics:

In float glass manufacturing, hydrogen is required to prevent oxidation of the large tin bath.

Food and Beverages:

It is used to hydrogenate unsaturated fatty acids in animal and vegetable oils, producing solid fats for

margarine and other food products.

Electronics:


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Hydrogen is used as a carrier gas for such active trace elements as arsine and phospine, in the

manufacture of semi-conducting layers in integrated circuits.

Miscellaneous:

Generators in large power plants are often cooled with hydrogen, since the gas processes high thermal

conductivity and offers low friction resistance.

Liquid hydrogen is used as a rocket fuel.

The nuclear fuel industry uses hydrogen as a protective atmosphere in the fabrication of fuel rods.

Interesting Facts and Information about Hydrogen (H2):

y Hydrogen (H2) is a colorless, odorless, tasteless, flammable and nontoxic gas at atmospheric

temperatures and pressures. It is the most abundant element in the universe, but is almost absent

from the atmosphere as individual molecules in the upper atmosphere can gain high velocities

during collisions with heavier molecules, and become ejected from the atmosphere. It is still quiteabundant on Earth, but as part of compounds such as water.

y Hydrogen burns in air with a pale blue, almost invisible flame. Hydrogen is the lightest of all gases,

approximately one-fifteenth as heavy as air. Hydrogen ignites easily and forms, together with

oxygen or air, an explosive gas (oxy-hydrogen).

y Hydrogen has the highest combustion energy release per unit of weight of any commonly

occurring material. This property makes it the fuel of choice for upper stages of multi-stage

rockets.

y

Hydrogen has the lowest boiling point of any element except helium. When cooled to its boilingpoint, -252.76

oC (-422.93

oF) hydrogen becomes a transparent, odorless liquid that is only one-

fourteenth as heavy as water. Liquid hydrogen is not corrosive or particularly reactive. When

converted from liquid to gas, hydrogen expands approximately 840 times. Its low boiling point and

low density result in liquid hydrogen spills dispersing rapidly.

y The most common large-scale process for manufacturing hydrogen is steam reforming of

hydrocarbons, in particular, natural gas (mostly methane). Other methods used for hydrogen

production methods include generation by partial oxidation of coal or hydrocarbons, electrolysis

of water, recovery of byproduct hydrogen from electrolytic cells used to produce chlorine and

other products, and dissociation of ammonia. Hydrogen is recovered for internal use and sale

from various refinery and chemical streams, typically purge gas, tail gas, fuel gas or other

contaminated or low-valued streams. Purification methods include pressure swing adsorption

(PSA), cryogenic separation and membrane gas separation.

y Many hydrogen gas users purchase it as a liquid, which can be vaporized as needed, instead of

producing it on their own site. Liquefaction of gaseous hydrogen is a multi-stage process using

several refrigerants and compression/ expansion loops to produce extreme cold. As part of the

process, the hydrogen passes through "ortho/ para" conversion catalyst beds that convert most of

the "ortho" hydrogen to the "para" form. These two types of diatomic hydrogen have different


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energy states. In "ortho" hydrogen, which is the most common form at room temperature, the

nuclei have "anti-parallel" spins. In "para" hydrogen the nuclei have parallel spins. "Ortho"

hydrogen is less stable than "para" at liquid hydrogen temperatures. It spontaneously changes to

the "para" form, releasing energy, which vaporizes a portion of the liquid. By using a catalyst such

as hydrous ferric oxide to convert most of the hydrogen to the more stable form during the

liquefaction process, the liquid hydrogen product can be stored without excessive vent loss.

y Some industrial processes with relatively small hydrogen requirements may choose to produce

some or all of their needs using compact generators. In the past, ammonia dissociation was a

common technology choice. More recently, improvements in small packaged electrolytic and

hydrocarbon reforming systems have made these routes to small volume hydrogen production

increasingly attractive. In some cases these systems may be the sole source of hydrogen, while in

others they may be used to supplement and/or back-up other supply sources. Electrolytic

production techniques can produce high purity hydrogen at elevated pressure, eliminating the

need for supplemental compression. They can also produce high purity oxygen (at one-half the

hydrogen production rate). The latest generation of highly packaged hydrocarbon reforming

units, in particular those which employ an autothermal generation process, which operates at

relatively low-temperature and pressure, have made on-site hydrocarbon reforming a viable routeto hydrogen production at much lower production rates than were considered commercially

feasible just a few years ago.

y Much has been said about hydrogen being the "fuel of the future" due to its abundance and its

non-polluting combustion products. Less has been said about the fact that other forms of energy

must be used to produce the hydrogen which will be used as fuel. Most hydrogen is bound up in

compounds such as water or methane, and energy is required to break the hydrogen free from

these compounds, then separate, purify, compress and/ or liquefy the hydrogen for storage and

transportation to usage points. Widespread production, distribution and use of hydrogen will

require many innovations and investments to be made in efficient and environmentally-

acceptable production systems, transportation systems, storage systems and usage devices.

y Currently, there is a great deal of interest in hydrogen fuel cell technology development and

investigations into unconventional or specialized hydrogen storage systems. New technologies

and equipment developed to support these applications will undoubtedly find uses in industry as

well.

Rare Gases Applications and Uses for Neon (Ne), Krypton (Kr) and

Xenon (Xe):

Lighting:

Neon is commonly recognized as the gas that produces the glow in "neon" lights (which often contain

other gases as well). Neon's natural red color can be turned into a wide range of effective decorative

lighting colors by mixing neon with other gases, by using colored glass tubes or by depositing fluorescent

powder coatings inside the glass tubes. Neon is also used to produce a red glow in indicator lamps and

lasers.


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Krypton is used in halogen sealed beam headlights to increase light output by allowing thinner filaments

to be used with acceptable useful lifetimes. Krypton is also used in in lasers, in particular mixed with

fluorine to create an "excimer" mixture that is a precursor to a molecule which exists in the excited state

but not in the ground state. In excimer lasers, the gas mixture is pulsed to form short-lived excited

molecules which release energy by light emission as the constituents return to the ground state. Krypton-

fluorine excimer lasers produce high-power ultraviolet light used in eye surgery. Other applications are

sterilization of fluids and lithographic fabrication of semiconductors.

Xenon has a light spectrum that is much wider than neon or krypton and Xenon, with an overall bluish hue

that is perceived as being similar to "daylight". It is used in high-intensity aviation approach lights, in high-

efficiency incandescent bulbs for automotive and stage lighting uses, in plasma display panels, in

operating room and internal examination lighting, and in ultraviolet lasers.

Construction:

Argon and Krypton are used as a premium filler gases for high-efficiency dual-pane (and triple pane)

windows. Argon is about one-third heavier than nitrogen or dry air, and Krypton is twice as heavy as

Argon. They may be used individually or in a mixture.

These heavier filler gases minimize heat transmission by convective movement of the filler gas betweenthe panes of glass. The insulating value of the window (measured by R value) is roughly proportional to

the molecular weight of the filler gas, holding other possible construction differences such as the impact

of high efficiency (Low E) glass coatings and triple versus dual-pane construction constant. Noise

transmission through windows is also reduced as the molecular weight of the fil ler gas increases.

Argon is about 5 times as expensive as dry nitrogen, but so little is used in a window that the benefits of

using it are easily justified. Argon has become the preferred gas to use in most multi-paned windows.

Krypton costs much more than argon, often about 100 times as much for the same volume. This price

disparity is mainly due to the much lower concentration of Krypton than Argon in air. Only a small number

of air separation plants process enough air to make production of Krypton economically attractive.

Low Temperature Refrigeration:

Neon, with a boiling point lower than all the gases except helium and hydrogen, can be used as a very low

temperature refrigerant. On a volume basis, Neon has 3 times the refrigerating capacity of liquid

hydrogen and over 40 times the refrigerating capacity of liquid helium.

Interesting Facts and Information about the "Rare Gases":

y The so-called "rare" gases Neon (Ne), Krypton (Kr) and Xenon (Xe), are present in air in very low

concentrations. Like the other "noble" or "inert" gases, helium (He), argon (Ar) and radon (Rn),

Neon, Krypton and Xenon remain in the air because they do not combine with other materials to

form solid or liquid compounds. All of these gases are monatomic.

y Neon, Krypton and Xenon are valued for their light emitting properties when electrically charged.

Krypton and Xenon are also valued for their total inertness coupled with high molecular weight

(83.80 and 131.30, respectively). Krypton and Xenon are about two to three times as heavy as

argon (molecular weight 39.95) and approximately three to four times as heavy as nitrogen

(molecular weight 28.0) which is used as in inert gas in many applications, but is not a true inert

gas. These properties are put to good use in multi-pane windows to reduce heat loss due to


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Works Cited

http://www.uigi.com/gas_props_uses.html

http://www.search.com/industrial_gases

http://www.uigi.com/oxygen.html

http://www.uigi.com/nitrogen.html

http://www.uigi.com/argon.html

http://www.uigi.com/rare_gases.html

http://www.uigi.com/carbondioxide.html

http://www.uigi.com/hydrogen.html

http://nzic.org.nz/ChemProcesses/production/1K.pdf

www.acetylene.com


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cpi industrial gases

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