Crematory
Encyclopedia
A crematory is a machine in which cremation
takes place. Crematories are usually found in funeral homes, cemeteries, or in stand-alone facilities. A facility which houses the actual cremator units is referred to as a crematorium.
, any cremation which took place was on an outdoor, open pyre. With firewood, and to a lesser extent, coal being the only available fuel options and the low energy efficiency inherent in such a configuration, it is no surprise that cremation enjoyed very minimal popularity in densely populated areas up until furnace technology developed during the Industrial Revolution could be applied to cremation to make it more practical in an urbanizing world.
, who together with colleagues founded the Cremation Society of England in 1874. The first crematoria in Europe were built in 1878 in Woking
, Surrey
, England (see Woking Crematorium
) and Gotha
, Germany
, the first in North America
, the LeMoyne Crematory
, in 1876 by Dr. Francis Julius LeMoyne in Washington, Pennsylvania
. The second cremation in the United States
was that of Charles F. Winslow in Salt Lake City, Utah
on 31 July 1877. The first cremation in Britain took place on 26 March 1886 at Woking. Newer crematories now have a feature called 'hot hearth crematory' which is a 2 chamber technology which allows the body to burn in the upper chamber and the lower chamber to allow heat to be carried thru the bottom to keep the top chamber hot.
Cremation
was declared as legal in England and Wales when Dr. William Price was prosecuted for cremating his son; formal legislation followed later with the passing of the Cremation Act of 1902 (this Act did not extend to Ireland
), which imposed procedural requirements before a cremation could occur and restricted the practice to authorised places. Some of the various Protestant churches came to accept cremation, with the rationale being, "God can resurrect a bowl of ashes just as conveniently as he can resurrect a bowl of dust." The 1908 Catholic Encyclopedia was critical about these efforts, referring to them as a "sinister movement" and associating them with Freemasonry
, although it said that "there is nothing directly opposed to any dogma of the Church in the practice of cremation." In 1963, Pope Paul VI
lifted the ban on cremation, and in 1966 allowed Catholic priests to officiate at cremation ceremonies.
Australia
also started to establish modern cremation movements and societies. Australians had their first purpose-built modern crematorium and chapel in the West Terrace Cemetery in the South Australia
n capital of Adelaide
in 1901. This small building, resembling the buildings at Woking, remained largely unchanged from its 19th-century style and was in full operation until the late 1950s. The oldest operating crematorium in Australia is at Rookwood, in Sydney
which opened in 1925.
, most cremation in industrialized nations takes place within enclosed furnaces designed to maximize utilization of the thermal energy consumed while minimizing the emission of smoke and odors.
which requires a very large amount of thermal energy.
A 68 kg body which contains 65% water will require 100 MJ
of thermal energy before any combustion will take place. 100 MJ
is approximately equivalent to 3 m3 (105 ft3) of natural gas
, or 3 liters of fuel oil
(0.8 US gallons). Additional energy is necessary to make up for the heat capacity
("preheating") of the furnace, fuel burned for emissions control, and heat losses through the insulation and in the flue gases.
As a result, cremators are most often heated by burners fueled by natural gas. LPG
(propane/butane) or fuel oil may be used where natural gas is not available. These burners can range in power from 150 kW (0.5 MMBTU/h) to over 800 kW (1.5 MMBTU/h).
Cremators heated by electricity
also exist in India, where electric heating elements bring about cremation without the direct application of flame to the body.
Coal, coke, and wood were used in the past, heating the chambers from below (like a cooking pot). This resulted in an indirect heat and prevented mixing of ash from the fuel with ash from the body. The term retort
when applied to cremation furnaces originally referred to this design.
There has been interest, mainly in developing nations, to develop a cremator heated by concentrated solar energy.
ceramic brick designed to withstand the high temperatures.
The primary chamber contains the body - one at a time usually contained in some type of combustible casket or container. This chamber has at least one burner to provide the heat which vaporizes the water content of the body and aids in combustion of the organic portion. A large door exists to load the body container. Temperature in the primary chamber is typically between 760 to 1150 °C
(1400 to 2100 °F
). Higher temperatures speed cremation but consume more energy, generate more oxides of nitrogen
, and accelerate spalling of the furnace's refractory lining.
The secondary chamber may be at the rear or above the primary chamber. A secondary burner(s) fires into this chamber, oxidizing any organic material which passes from the primary chamber. This acts as a method of pollution control to eliminate the emission of odors and smoke. The secondary chamber typically operates at a temperature greater than 900°C (1650°F).
networks has arisen in recent years. Such heat recovery efforts have been viewed in both a positive and negative light by the public.
In addition, filtration systems (baghouses
) are being applied to crematoria in many countries. Activated carbon
adsorption is being considered for mercury
abatement (as a result of dental amalgam). Much of this technology is borrowed from the waste incineration industry on a scaled-down basis. With the rise in the use of cremation in Western nations where amalgam has been used liberally in dental restorations, mercury has been a growing concern.
The time to carry out a cremation can vary from 70 minutes to approximately 200 minutes. Cremators used to run on timers (some still do) and one would have to determine the weight of the body therefore calculating how long the body has to be cremated for and set the timers accordingly. Other types of cremators merely have a start and a stop function for the cremation, displayed on the user interface. The end of the cremation must be judged by the operator who in turn stops the cremation process.
Cremation
Cremation is the process of reducing bodies to basic chemical compounds such as gasses and bone fragments. This is accomplished through high-temperature burning, vaporization and oxidation....
takes place. Crematories are usually found in funeral homes, cemeteries, or in stand-alone facilities. A facility which houses the actual cremator units is referred to as a crematorium.
History
Prior to the Industrial RevolutionIndustrial Revolution
The Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times...
, any cremation which took place was on an outdoor, open pyre. With firewood, and to a lesser extent, coal being the only available fuel options and the low energy efficiency inherent in such a configuration, it is no surprise that cremation enjoyed very minimal popularity in densely populated areas up until furnace technology developed during the Industrial Revolution could be applied to cremation to make it more practical in an urbanizing world.
The first modern crematory
In 1873, Paduan Professor Brunetti presented a cremation chamber at the Vienna Exposition. In Britain, the movement found the support of Queen Victoria's surgeon, Sir Henry ThompsonSir Henry Thompson, 1st Baronet
Sir Henry Thompson, 1st Baronet FRCS , British surgeon and polymath, was born at Framlingham, Suffolk.-Medical career:...
, who together with colleagues founded the Cremation Society of England in 1874. The first crematoria in Europe were built in 1878 in Woking
Woking
Woking is a large town and civil parish that shares its name with the surrounding local government district, located in the west of Surrey, UK. It is part of the Greater London Urban Area and the London commuter belt, with frequent trains and a journey time of 24 minutes to Waterloo station....
, Surrey
Surrey
Surrey is a county in the South East of England and is one of the Home Counties. The county borders Greater London, Kent, East Sussex, West Sussex, Hampshire and Berkshire. The historic county town is Guildford. Surrey County Council sits at Kingston upon Thames, although this has been part of...
, England (see Woking Crematorium
Woking Crematorium
Woking Crematorium is a crematorium in Woking, a large town in the west of Surrey, England. Established in 1878, it was the first custom-built crematorium in the United Kingdom and is closely linked to the history of cremation in this country.-Location:...
) and Gotha
Gotha (town)
Gotha is a town in Thuringia, within the central core of Germany. It is the capital of the district of Gotha.- History :The town has existed at least since the 8th century, when it was mentioned in a document signed by Charlemagne as Villa Gotaha . Its importance derives from having been chosen in...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, the first in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, the LeMoyne Crematory
LeMoyne Crematory
The LeMoyne Crematory was the first crematory in the United States. Francis Julius LeMoyne had it built in 1876, with the first cremation in world history being preformed on December 6, 1876....
, in 1876 by Dr. Francis Julius LeMoyne in Washington, Pennsylvania
Washington, Pennsylvania
Washington is a city in and the county seat of Washington County, Pennsylvania, United States, within the Pittsburgh Metro Area in the southwestern part of the state...
. The second cremation in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
was that of Charles F. Winslow in Salt Lake City, Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
on 31 July 1877. The first cremation in Britain took place on 26 March 1886 at Woking. Newer crematories now have a feature called 'hot hearth crematory' which is a 2 chamber technology which allows the body to burn in the upper chamber and the lower chamber to allow heat to be carried thru the bottom to keep the top chamber hot.
Cremation
Cremation
Cremation is the process of reducing bodies to basic chemical compounds such as gasses and bone fragments. This is accomplished through high-temperature burning, vaporization and oxidation....
was declared as legal in England and Wales when Dr. William Price was prosecuted for cremating his son; formal legislation followed later with the passing of the Cremation Act of 1902 (this Act did not extend to Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
), which imposed procedural requirements before a cremation could occur and restricted the practice to authorised places. Some of the various Protestant churches came to accept cremation, with the rationale being, "God can resurrect a bowl of ashes just as conveniently as he can resurrect a bowl of dust." The 1908 Catholic Encyclopedia was critical about these efforts, referring to them as a "sinister movement" and associating them with Freemasonry
Freemasonry
Freemasonry is a fraternal organisation that arose from obscure origins in the late 16th to early 17th century. Freemasonry now exists in various forms all over the world, with a membership estimated at around six million, including approximately 150,000 under the jurisdictions of the Grand Lodge...
, although it said that "there is nothing directly opposed to any dogma of the Church in the practice of cremation." In 1963, Pope Paul VI
Pope Paul VI
Paul VI , born Giovanni Battista Enrico Antonio Maria Montini , reigned as Pope of the Catholic Church from 21 June 1963 until his death on 6 August 1978. Succeeding Pope John XXIII, who had convened the Second Vatican Council, he decided to continue it...
lifted the ban on cremation, and in 1966 allowed Catholic priests to officiate at cremation ceremonies.
Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
also started to establish modern cremation movements and societies. Australians had their first purpose-built modern crematorium and chapel in the West Terrace Cemetery in the South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
n capital of Adelaide
Adelaide
Adelaide is the capital city of South Australia and the fifth-largest city in Australia. Adelaide has an estimated population of more than 1.2 million...
in 1901. This small building, resembling the buildings at Woking, remained largely unchanged from its 19th-century style and was in full operation until the late 1950s. The oldest operating crematorium in Australia is at Rookwood, in Sydney
Sydney
Sydney is the most populous city in Australia and the state capital of New South Wales. Sydney is located on Australia's south-east coast of the Tasman Sea. As of June 2010, the greater metropolitan area had an approximate population of 4.6 million people...
which opened in 1925.
Technology
While open outdoor pyres were used in the past and are often still used in many areas of the world today, notably IndiaIndia
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, most cremation in industrialized nations takes place within enclosed furnaces designed to maximize utilization of the thermal energy consumed while minimizing the emission of smoke and odors.
Thermodynamics
A human body usually contains a negative caloric value, meaning that energy is required to combust it. This is a result of the high water content; all water must be vaporizedLatent heat
Latent heat is the heat released or absorbed by a chemical substance or a thermodynamic system during a process that occurs without a change in temperature. A typical example is a change of state of matter, meaning a phase transition such as the melting of ice or the boiling of water. The term was...
which requires a very large amount of thermal energy.
A 68 kg body which contains 65% water will require 100 MJ
Orders of magnitude (energy)
This list compares various energies in joules , organized by order of magnitude.-SI multiples:-See also:*Conversion of units of energy*Energies per unit mass*List of energy topics*Metric system*TNT equivalent*Scientific notation-Notes:...
of thermal energy before any combustion will take place. 100 MJ
is approximately equivalent to 3 m3 (105 ft3) of natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
, or 3 liters of fuel oil
Fuel oil
Fuel oil is a fraction obtained from petroleum distillation, either as a distillate or a residue. Broadly speaking, fuel oil is any liquid petroleum product that is burned in a furnace or boiler for the generation of heat or used in an engine for the generation of power, except oils having a flash...
(0.8 US gallons). Additional energy is necessary to make up for the heat capacity
Heat capacity
Heat capacity , or thermal capacity, is the measurable physical quantity that characterizes the amount of heat required to change a substance's temperature by a given amount...
("preheating") of the furnace, fuel burned for emissions control, and heat losses through the insulation and in the flue gases.
As a result, cremators are most often heated by burners fueled by natural gas. LPG
LPG
LPG may stand for:* Liquefied petroleum gas* Laboratoire de Planetologie, Grenoble, France* Landwirtschaftliche Produktionsgenossenschaft * Llanfairpwll railway station, Wales; National Rail station code LPG.* LPG...
(propane/butane) or fuel oil may be used where natural gas is not available. These burners can range in power from 150 kW (0.5 MMBTU/h) to over 800 kW (1.5 MMBTU/h).
Cremators heated by electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
also exist in India, where electric heating elements bring about cremation without the direct application of flame to the body.
Coal, coke, and wood were used in the past, heating the chambers from below (like a cooking pot). This resulted in an indirect heat and prevented mixing of ash from the fuel with ash from the body. The term retort
Retort
In a chemistry laboratory, a retort is a glassware device used for distillation or dry distillation of substances. It consists of a spherical vessel with a long downward-pointing neck. The liquid to be distilled is placed in the vessel and heated...
when applied to cremation furnaces originally referred to this design.
There has been interest, mainly in developing nations, to develop a cremator heated by concentrated solar energy.
Combustion System
A typical unit contains a primary and secondary combustion chamber. These chambers are lined with a refractoryRefractory
A refractory material is one that retains its strength at high temperatures. ASTM C71 defines refractories as "non-metallic materials having those chemical and physical properties that make them applicable for structures, or as components of systems, that are exposed to environments above...
ceramic brick designed to withstand the high temperatures.
The primary chamber contains the body - one at a time usually contained in some type of combustible casket or container. This chamber has at least one burner to provide the heat which vaporizes the water content of the body and aids in combustion of the organic portion. A large door exists to load the body container. Temperature in the primary chamber is typically between 760 to 1150 °C
Celsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
(1400 to 2100 °F
Fahrenheit
Fahrenheit is the temperature scale proposed in 1724 by, and named after, the German physicist Daniel Gabriel Fahrenheit . Within this scale, the freezing of water into ice is defined at 32 degrees, while the boiling point of water is defined to be 212 degrees...
). Higher temperatures speed cremation but consume more energy, generate more oxides of nitrogen
Nitrogen oxide
Nitrogen oxide can refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:* Nitric oxide, also known as nitrogen monoxide, , nitrogen oxide* Nitrogen dioxide , nitrogen oxide...
, and accelerate spalling of the furnace's refractory lining.
The secondary chamber may be at the rear or above the primary chamber. A secondary burner(s) fires into this chamber, oxidizing any organic material which passes from the primary chamber. This acts as a method of pollution control to eliminate the emission of odors and smoke. The secondary chamber typically operates at a temperature greater than 900°C (1650°F).
Air Pollution Control and Energy Recovery
The flue gases from the secondary chamber are usually vented to the atmosphere through a refractory-lined flue. They are at a very high temperature, and interest in recovering this thermal energy e.g. for space heating of the funeral chapel or other facilities or for distribution into local district heatingDistrict heating
District heating is a system for distributing heat generated in a centralized location for residential and commercial heating requirements such as space heating and water heating...
networks has arisen in recent years. Such heat recovery efforts have been viewed in both a positive and negative light by the public.
In addition, filtration systems (baghouses
Dust collector
A dust collector is a system used to enhance the quality of air released from industrial and commercial processes by collecting dust and other impurities from air or gas. Designed to handle heavy dust loads, a dust collector system consists of a blower, dust filter, a filter-cleaning system, and a...
) are being applied to crematoria in many countries. Activated carbon
Activated carbon
Activated carbon, also called activated charcoal, activated coal or carbo activatus, is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for adsorption or chemical reactions.The word activated in the name is sometimes replaced...
adsorption is being considered for mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
abatement (as a result of dental amalgam). Much of this technology is borrowed from the waste incineration industry on a scaled-down basis. With the rise in the use of cremation in Western nations where amalgam has been used liberally in dental restorations, mercury has been a growing concern.
Automation
The application of computer control has allowed the cremator to be more automated, in that temperature and oxygen sensors within the unit along with pre-programmed algorithms based upon the weight of the deceased allow the unit to operate with less user intervention. Such computer systems may also streamline recordkeeping requirements for tracking, environmental, and maintenance purposes.Additional Aspects
- Cremation time
The time to carry out a cremation can vary from 70 minutes to approximately 200 minutes. Cremators used to run on timers (some still do) and one would have to determine the weight of the body therefore calculating how long the body has to be cremated for and set the timers accordingly. Other types of cremators merely have a start and a stop function for the cremation, displayed on the user interface. The end of the cremation must be judged by the operator who in turn stops the cremation process.