Kerosene lamp

The kerosene lamp (widely known in Britain as a paraffin lamp) is a type of lighting device that uses kerosene (British "paraffin", as distinct from paraffin wax or paraffin oil) as a fuel. Kerosene lamps have a wick or mantle as light source, protected by a glass chimney or globe; lamps may be used on a table, or hand-held lanterns may used for portable lighting. There are three types of kerosene lamp: flat wick, central draught (tubular round wick), and mantle lamp. Kerosene lanterns meant for portable use a flat wick and are made in dead flame, hot blast, and cold blast variants.

Pressurized kerosene lamps have a gas generator and gas mantle; these are known as Petromax, Tilley lamps, or Coleman lamps, among other manufacturers. They produce more light per unit of fuel than wick-type lamps, but are more complex and expensive in construction, and more complex to operate. A hand-pump pressurizes air, which forces liquid fuel from a reservoir into a gas generator. Vapor from the gas generator burns, heating a mantle to incandescence and also providing heat to the gas generator.

The first description of a simple lamp using crude mineral oil was provided by al-Razi (Rhazes) in 9th century Baghdad, who referred to it as the "naffatah" in his Kitab al-Asrar (Book of Secrets).[1] In 1846 Abraham Pineo Gesner invented a substitute for whale oil for lighting, distilled from coal. Later made from petroleum, kerosene became a popular lighting fuel. Modern versions of the kerosene lamp were later constructed by the Polish inventor Ignacy Łukasiewicz in 1853 Lviv.

Kerosene lamps are widely used for lighting in rural areas of Africa and Asia where electricity is not distributed, or is too costly. Kerosene lamps consume an estimated 77 billion litres of fuel per year, equivalent to 1.3 million barrels of oil per day,[2] comparable to annual U.S. jet fuel consumption of 76 billion litres per year.[3]
Flat wick lamp A flat-wick lamp is a simple type of kerosene lamp, which burns kerosene drawn up through a wick by capillary action. If this type of lamp is broken it can easily start a fire. A flat-wick lamp has a fuel tank (fount), with the lamp burner attached. Attached to the fuel tank, four prongs hold the glass chimney, which acts to prevent the flame from being blown out and enhances a thermally induced draft. The glass chimney needs a "throat," or slight constriction, to create the proper draft for complete combustion of the fuel; the draft carries more air (oxygen) past the flame, helping to produce a smokeless light which is brighter than an open flame would produce.

The lamp burner has a flat wick, usually made of cotton. The lower part of the wick dips into the fount and absorbs the kerosene; the top part of the wick extends out of the wick tube of the lamp burner, which includes a wick-adjustment mechanism. Adjusting how much of the wick extends above the wick tube controls the flame. The wick tube surrounds the wick, and ensures that the correct amount of air reaches the lamp burner. Adjustment is usually done by means of a small knob operating a cric, which is a toothed, metal sprocket bearing against the wick. If the wick is too high, and extends beyond the burner cone at the top of the wick tube, the lamp will produce smoke and soot (unburned carbon). When the lamp is lit, the kerosene that the wick has absorbed burns and produces a clear, bright, yellow flame. As the kerosene burns, capillary action in the wick draws more kerosene up from the fuel tank. All kerosene flat wick lamps use the dead flame burner design, where the flame is fed cold air from below and hot air exits above.

Central draft (tubular round wick) lamp Main article: Argand lamp
 
"Central-draught" tubular wick kerosene lampA central draught lamp, or Argand lamp, works in the same manner as the flat wick lamp. The burner is equipped with a tall glass chimney, of around 12 inches tall or taller, to provide the powerful draft this lamp requires to burn properly. The burner uses a wick, usually made of cotton, that is made of a wide, flat wick rolled into a tube, the seam of which is then stitched together to form the complete wick. The tubular wick is then mounted into a "carrier," which is some form of a toothed rack that engages into the gears of the wick-raising mechanism of the burner and allows the wick to be raised and lowered. The wick rides in between the inner and outer wick tubes; the inner wick tube (central draft tube) provides the "central draft" or draft that supplies air to the flame spreader. When the lamp is lit, the central draft tube supplies air to the flame spreader that spreads out the flame into a ring of fire and allows the lamp to burn cleanly.

Mantle lamp Main article: Gas mantle
A variation on the "central draught" lamp is the mantle lamp. The mantle is a roughly pear-shaped mesh made of fabric placed over the burner. The Mantle typically contains thorium or other rare-earth salts; on first use the cloth burns away and the rare-earth salts are converted to oxides, leaving a very fragile structure which incandesces (glows brightly) upon exposure to the heat of the burner flame. Mantle lamps are considerably brighter than flat- or round-wick lamps, produce a whiter light and generate more heat. Mantle lamps typically use fuel faster than a flat wick lamp, but slower than a center-draugh round wick as they depend on a small flame heating a mantle, rather than having all the light coming from the flame itself.

Mantle lamps are nearly always bright enough to benefit from a lampshade and a few mantle lamps may be enough to heat a small building in cold weather. Mantle lamps, because of the higher temperature at which they operate, do not produce much odor, except when first lit or extinguished. Like flat- and round-wick lamps, they can be adjusted for brightness; however caution must be used because if set too high the lamp chimney and the mantle can become covered with black areas of soot. A lamp set too high will burn off its soot harmlessly if quickly turned down, but if not caught soon enough the soot itself can ignite and a "runaway lamp" condition can result.

One popular model of mantle lamp uses only a wick and is unpressurized.

Pressurized mantle lamps contain a gas generator and require preheating the generator before lighting. An air pump is used to deliver fuel under pressure to the gas generator.

Large fixed pressurized kerosene mantle lamps were used in lighthouse beacons for navigation of ships, brighter and with lower fuel consumption than oil lamps used before.[4]

Kerosene lantern 
Dead flameA kerosene lantern, also known as a "barn lantern" or "hurricane lantern," is a flat-wick lamp made for portable and outdoor use. They are made of soldered or crimped-together sheet metal stampings, with tin-plated sheet steel being the most common material, followed by brass and copper. There are three types: Dead flame, hot blast, and cold blast. Both hot blast and cold blast designs are called tubular lanterns and are safer than dead flame lamps as tipping over a tubular lantern cuts off the oxygen flow to the burner and will extinguish the flame within seconds.[5]

Dead flame The earliest portable kerosene "glass globe" lanterns, of the 1850s and 60s, were of the dead-flame type meaning that it had an open wick, but the airflow to the flame was strictly controlled in an upward motion by a combination of vents at the bottom of the burner and an open topped chimney. This had the effect of removing side-to-side drafts and thus significantly reducing or even eliminating the flickering that can occur with an exposed flame.

Later lanterns such as the Hot Blast and Cold Blast lanterns took this airflow control even further by partially enclosing the wick in a "deflector" or "burner cone" and channeling the airflow through that restricted area creating a brighter and even more stable flame.

Hot blast 
Hot-blast 
Cold-blast

The hot-blast design, also known as a "tubular lantern" due to the metal tubes used in its construction, was invented by John Irwin and patented on January 12, 1868. The hot-blast design collected hot air from above the globe and fed it through metal side tubes to the burner, to make the flame burn brighter.

Cold blast The cold-blast design is similar to the hot-blast, except that cold fresh air is drawn in from around the top of the globe and is then fed though the metal side tubes to the flame, making it burn brighter. This design produces a brighter light than the hot blast design, because the fresh air that is fed to the flame has plenty of oxygen to support the combustion process.

 

Operation and maintenance Lighting a flat-wick lamp requires filling the fuel tank (fount) with fuel and allowing time for the wick to absorb the fuel. The wick is trimmed straight across with a pair of sharp scissors before lighting. With the glass chimney lifted off the lamp, the wick is turned up and lighted with a match or other lighter. The wick is turned down if smoke develops, and the lamp chimney lowered. After a few minutes warm-up the lamp can be turned to full brightness. Extinguishing the lamp is done by turning down the wick and blowing out the flame, or by turning the wick down below the top of the wick tube. Most non branded burners are not designed to be turned down to extinguish the wick and should be blown out. The generic or non branded burner may be designed to load multiple size wicks and have too much space in the wick tube. Turning down the wick in this type of burner could lead to a hot or lit wick dropped in the fuel tank (fount).

Mantle lamps, and other lamps that use the "central-draught" tubular wick burner are lit in a similar fashion. The wick on a mantle lamp or "central-draught" tubular wick lamp is trimmed only with a special wick cleaner to remove the carbon off the top of the wick and to leave a smooth surface on the top of it.

Maintenance can be performed on the burner by inspecting the wick tube, making sure the wick moving mechanism works freely, moving the tongs holding the glass chimney for a snug fit, and cleaning and inspecting the glass chimney. The burner should fit snug with the burner collar and the fuel tank should be inspected for leaks and damage.

Fuels Generic lamp oil is available clear or in a choice of several colors and in scented and unscented forms. Although more expensive, Lamp oil is highly refined and burns more cleanly and with less odor than kerosene. "Water clear" K-1 kerosene is the next grade of preferred fuel for kerosene wick lamps. In some locations they sell Red kerosene which is dyed red and is slightly less expensive than K-1 kerosene, as no motor-fuel taxes are collected on it. Red dyed kerosene is not recommended as the dye will gradually clog the lantern wick causing odor and reduced performance. "Klean-Heat" brand is another highly refined fuel cleaner-burning, nicer-smelling[citation needed] kerosene substitute, sold at many hardware stores during winter. Citronella oil is a citronella-scented lamp oil; some brands also have lemongrass oil in them and they are used for their insect repellent properties. Citronella and lemongrass fuels should only be used outdoors.

Kerosene wick lamps should only be operated with kerosene or lamp oil, but alternative fuels are used in an emergency. Such fuels may produce additional smoke and odor and may not be usable indoors. Tractor vaporizing oil is made from kerosene with some additive to make a motor fuel for tractors. No. 1 diesel fuel (also called winter diesel) is about the same as kerosene but with the additives to make it a motor fuel. Jet A jet-engine fuel is essentially kerosene with a few additives.

Any liquid with a low flash point presents a high risk of fire or explosion if used in a kerosene wick lamp. Such liquids are DANGEROUS and should NEVER be used in a Kerosene lamp or lantern. Examples include:

Charcoal lighter fluid
Gasoline (petrol)
Naphtha, white gas or coleman fuel
mineral spirits, paint thinner, white spirit (Stoddard solvent)
other hydrocarbon solvents such as turpentine, benzene, xylene, toluene, acetone, camphene, lacquer thinner
denatured alcohol.
Contamination of lamp fuel with even a small amount of gasoline results in a lower flash point and higher vapor pressure for the fuel, with potentially dangerous consequences. Vapors from spilled fuel may ignite; vapor trapped above liquid fuel may lead to excess pressure and fires. Kerosene lamps are still extensively used in areas without electrical lighting; the cost and dangers of combustion lighting are a continuing concern in many countries.[6]

Performance Wick-type lamps have the lowest light output, and pressurized lamps have higher output; the range is from 20 to 100 lumens. A kerosene lamp producing 37 lumens for 4 hours per day will consume about 3 litres of kerosene per month.[7]