![Puunene mill](https://upload.wikimedia.org/wikipedia/commons/8/8e/Puunene_mill.jpg)
A sugar refinery is a
refinery
A refinery is a production facility composed of a group of chemical engineering unit processes and unit operations refining certain materials or converting raw material into products of value.
Types of refineries
Different types of refineries ...
which processes
raw sugar
Brown sugar is unrefined or partially refined soft sugar.
Brown Sugar may also refer to:
Arts, entertainment, and media Films
* ''Brown Sugar'' (1922 film), a 1922 British silent film directed by Fred Paul
* ''Brown Sugar'' (1931 film), a 1931 ...
from
cane
Cane or caning may refer to:
*Walking stick or walking cane, a device used primarily to aid walking
*Assistive cane, a walking stick used as a mobility aid for better balance
*White cane, a mobility or safety device used by many people who are b ...
or
beets
The beetroot is the taproot portion of a beet plant, usually known in North America as beets while the vegetable is referred to as beetroot in British English, and also known as the table beet, garden beet, red beet, dinner beet or golden beet ...
into
white refined sugar
White sugar, also called table sugar, granulated sugar, or regular sugar, is a commonly used type of sugar, made either of beet sugar or cane sugar, which has undergone a refining process.
Description
The refining process completely removes t ...
.
Many
cane sugar mill
A sugar cane mill is a factory that processes sugar cane to produce raw or white sugar.
The term is also used to refer to the equipment that crushes the sticks of sugar cane to extract the juice.
Processing
There are a number of steps in p ...
s produce raw sugar, which is sugar that still contains
molasses
Molasses () is a viscous substance resulting from refining sugarcane or sugar beets into sugar. Molasses varies in the amount of sugar, method of extraction and age of the plant. Sugarcane molasses is primarily used to sweeten and flavour foods ...
, giving it more colour (and impurities) than the white sugar which is normally consumed in households and used as an ingredient in
soft drink
A soft drink (see § Terminology for other names) is a drink that usually contains water (often carbonated), a sweetener, and a natural and/or artificial flavoring. The sweetener may be a sugar, high-fructose corn syrup, fruit juice, a su ...
s and foods. While cane sugar does not need refining to be palatable, sugar from
sugar beet
A sugar beet is a plant whose root contains a high concentration of sucrose and which is grown commercially for sugar production. In plant breeding, it is known as the Altissima cultivar group of the common beet (''Beta vulgaris''). Together wi ...
is almost always refined to remove the strong, usually unwanted, taste of beets from it. The refined sugar produced is more than 99 percent pure
sucrose
Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula .
For human consumption, sucrose is extracted and refined ...
.
Many sugar mills only operate during the harvest season, whereas refineries may work the year round. Sugar beet refineries tend to have shorter periods when they process beet than cane refineries, but may store intermediate product and process it in the off-season. Raw sugar is either processed and sold locally, or is exported and refined elsewhere.
History
Sugar refineries date back to
Arab Egypt in the 12th century.
An artisanal version is the
trapiche
A trapiche is a mill made of wooden rollers used to extract juice from fruit, originally olives, and since the Middle Ages, sugar cane as well. By extension the word is also sometimes applied to the location of the mill, whether the workshop or t ...
, later substituted by the
engenho or . The British refining industry started in 1544 and was centred in the ports of Glasgow, Liverpool, Bristol and London. The risks involved in large refineries stimulated developments in the insurance industry. There were 16 fires in
Greenock
Greenock (; sco, Greenock; gd, Grianaig, ) is a town and administrative centre in the Inverclyde council areas of Scotland, council area in Scotland, United Kingdom and a former burgh of barony, burgh within the Counties of Scotland, historic ...
refineries between 1859 and 1895.
Tate & Lyle
Tate & Lyle PLC is a British-headquartered, global supplier of food and beverage ingredients to industrial markets. It was originally a sugar refining business, but from the 1970s it began to diversify, eventually divesting its sugar business i ...
became Britain's dominant refining company in the 20th century, but sold its sugar refining business in 2010 to
American Sugar Refining.
Sugar refineries are often located in heavy sugar-consuming regions such as North America, Europe, and Japan. Since the 1990s, many state-of-the art sugar refineries have been built in the
Middle East and North Africa
MENA, an acronym in the English language, refers to a grouping of countries situated in and around the Middle East and North Africa. It is also known as WANA, SWANA, or NAWA, which alternatively refers to the Middle East as Western Asia (or a ...
region, e.g. in
Dubai
Dubai (, ; ar, دبي, translit=Dubayy, , ) is the most populous city in the United Arab Emirates (UAE) and the capital of the Emirate of Dubai, the most populated of the 7 emirates of the United Arab Emirates.The Government and Politics of ...
,
Saudi Arabia
Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the fifth-largest country in Asia, the second-largest in the A ...
and
Algeria
)
, image_map = Algeria (centered orthographic projection).svg
, map_caption =
, image_map2 =
, capital = Algiers
, coordinates =
, largest_city = capital
, relig ...
. The world´s largest sugar refinery company is
American Sugar Refining with facilities in North America and Europe.
Raw sugar processing
Affination
![Redpath Sugar Plant Toronto 2010](https://upload.wikimedia.org/wikipedia/commons/1/12/Redpath_Sugar_Plant_Toronto_2010.jpg)
The raw sugar is stored in large warehouses and then transported into the sugar refinery by means of transport belts. In the traditional refining process, the raw sugar is first mixed with heavy syrup and
centrifuge
A centrifuge is a device that uses centrifugal force to separate various components of a fluid. This is achieved by spinning the fluid at high speed within a container, thereby separating fluids of different densities (e.g. cream from milk) or ...
d to wash away the outer coating of the raw sugar crystals, which is less pure than the crystal interior. Many sugar refineries today buy high pol sugar and can do without the affination process.
Screening
The remaining sugar is then dissolved to make a syrup (about 70 percent by weight solids), which is clarified by the addition of
phosphoric acid
Phosphoric acid (orthophosphoric acid, monophosphoric acid or phosphoric(V) acid) is a colorless, odorless phosphorus-containing solid, and inorganic compound with the chemical formula . It is commonly encountered as an 85% aqueous solution, w ...
and
calcium hydroxide that combine to precipitate
calcium phosphate
The term calcium phosphate refers to a family of materials and minerals containing calcium ions (Ca2+) together with inorganic phosphate anions. Some so-called calcium phosphates contain oxide and hydroxide as well. Calcium phosphates are whi ...
. The calcium phosphate particles entrap some impurities and absorb others, and then float to the top of the tank, where they are skimmed off.
After any remaining solids are filtered out, the clarified syrup is decolorized by filtration through the use of
bone char
Bone char ( lat, carbo animalis) is a porous, black, granular material produced by charring animal bones. Its composition varies depending on how it is made; however, it consists mainly of tricalcium phosphate (or hydroxyapatite) 57–80%, calci ...
, which is made from the bones of cattle, a bed of
activated carbon or, in more modern plants,
ion-exchange resin
An ion-exchange resin or ion-exchange polymer is a resin or polymer that acts as a medium for ion exchange. It is an insoluble matrix (or support structure) normally in the form of small (0.25–1.43 mm radius) microbeads, usually white or ye ...
.
Sugar house
![Sugarcentrifuge](https://upload.wikimedia.org/wikipedia/commons/d/d5/Sugarcentrifuge.JPG)
The purified syrup is then concentrated to supersaturation and repeatedly crystallized under vacuum to produce
white refined sugar
White sugar, also called table sugar, granulated sugar, or regular sugar, is a commonly used type of sugar, made either of beet sugar or cane sugar, which has undergone a refining process.
Description
The refining process completely removes t ...
. As in a sugar mill, the sugar crystals are separated from the
mother liquor
The mother liquor (or spent liquor) is the solution
Solution may refer to:
* Solution (chemistry), a mixture where one substance is dissolved in another
* Solution (equation), in mathematics
** Numerical solution, in numerical analysis, approx ...
by centrifuging. To produce
granulated sugar
White sugar, also called table sugar, granulated sugar, or regular sugar, is a commonly used type of sugar, made either of beet sugar or cane sugar, which has undergone a refining process.
Description
The refining process completely removes ...
, in which the individual sugar grains do not clump together, sugar must be dried.
Sugar drying and storage
Drying is accomplished first by drying the sugar in a hot rotary dryer, and then by blowing cool air through it for several days in conditioning silos. The finished product is stored in large concrete or steel silos. It is shipped in bulk,
big bags or bags to industrial customers or packed in consumer-size packages to
retailer
Retail is the sale of goods and services to consumers, in contrast to wholesaling, which is sale to business or institutional customers. A retailer purchases goods in large quantities from manufacturers, directly or through a wholesaler, and t ...
s.
The dried sugar must be handled with caution, as sugar
dust explosion
A dust explosion is the rapid combustion of fine particles suspended in the air within an enclosed location. Dust explosions can occur where any dispersed powdered combustible material is present in high-enough concentrations in the atmosphere o ...
s are possible. For example, a sugar dust explosion which led to 13 fatalities was the
2008 Georgia sugar refinery explosion in
Port Wentworth, GA.
Byproducts
*
Molasses
Molasses () is a viscous substance resulting from refining sugarcane or sugar beets into sugar. Molasses varies in the amount of sugar, method of extraction and age of the plant. Sugarcane molasses is primarily used to sweeten and flavour foods ...
*
Bagasse
Bagasse ( ) is the dry pulpy fibrous material that remains after crushing sugarcane or sorghum stalks to extract their juice. It is used as a biofuel for the production of heat, energy, and electricity, and in the manufacture of pulp and building ...
Factory automation in sugar refineries
As in many other industries
factory automation
Automation describes a wide range of technologies that reduce human intervention in processes, namely by predetermining decision criteria, subprocess relationships, and related actions, as well as embodying those predeterminations in machines ...
has been promoted heavily in sugar refineries in recent decades. The production process is generally controlled by a central
process control system, which directly controls most of the machines and components. Only for certain special machines such as the centrifuges in the sugar house decentralized
PLCs are used for security reasons.
References
Bibliography
*
External links
Sugar related online glossary.*
{{Authority control
Egyptian inventions
Industrial buildings
Refinery
A refinery is a production facility composed of a group of chemical engineering unit processes and unit operations refining certain materials or converting raw material into products of value.
Types of refineries
Different types of refineries ...