Cream separator
Encyclopedia
A separator is a centrifugal
device that separates milk
into cream
and skimmed milk
. Separation was commonly performed on farms in the past. Most farmers milked a few cows, usually by hand, and separated milk. Some of the skimmed milk was consumed while the rest was used to feed calves and pigs. Enough cream was saved to make butter
, and the excess was sold.
Today, milk is separated in industrial dairies
. Sufficient cream is returned to the skimmed milk before sale.
The centrifugal separator was first manufactured by Gustaf de Laval
, making it possible to separate cream from milk faster and more easily, without having to let the milk sit for a time, and risk it turning sour. Possibly because Gustaf de Laval
manufactured the first cream separators, many people credit the invention to de Laval. However, many patents appear before his, all of them labelled as 'improvements'. One of the first specifically for cream separation was patented by W. C. L. Lefeldt and C. G. O. Lentsch.
The original centrifugal separators were hand-cranked, as illustrated.
.
When spun, the heavier milk is pulled outward against the walls of the separator and the cream, which is lighter, collects in the middle. The cream and milk then flow out of separate spouts. Some floor model separators were built with a swinging platform attached to the stand. The bucket for collecting the cream was put on the platform, and a much larger bucket was set on the floor to collect the milk. Some floor model separators had two swinging platforms. Smaller versions of separators were called table-top models, for small dairies with only a few cows or goats.
Gustaf de Laval's construction made it possible to start the largest separator factory in the world, Alfa Laval AB
. The milk separator represented a significant industrial breakthrough in Sweden. Within the first decade in the 1900s, there were over twenty separator manufacturers in Stockholm
. Separators in modified form
are also used on ships to purify oil.
The original design had a manual bowl that required manual cleaning. Most modern separators use a self-ejecting centrifuge bowl that can automatically discharge any sedimentary solids that may be present, and that allow for clean-in-place
(CIP). The self-draining vessel feature is mandatory for machinery designated for 3A approval (an industrial sanitary standard).
Centrifuge
A centrifuge is a piece of equipment, generally driven by an electric motor , that puts an object in rotation around a fixed axis, applying a force perpendicular to the axis...
device that separates milk
Milk
Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many...
into cream
Cream
Cream is a dairy product that is composed of the higher-butterfat layer skimmed from the top of milk before homogenization. In un-homogenized milk, over time, the lighter fat rises to the top. In the industrial production of cream this process is accelerated by using centrifuges called "separators"...
and skimmed milk
Skimmed milk
Skimmed milk , or skim milk is made when all the cream is removed from whole milk .Sometimes only half the cream is removed, this is called semi-skimmed milk....
. Separation was commonly performed on farms in the past. Most farmers milked a few cows, usually by hand, and separated milk. Some of the skimmed milk was consumed while the rest was used to feed calves and pigs. Enough cream was saved to make butter
Butter
Butter is a dairy product made by churning fresh or fermented cream or milk. It is generally used as a spread and a condiment, as well as in cooking applications, such as baking, sauce making, and pan frying...
, and the excess was sold.
Today, milk is separated in industrial dairies
Dairy
A dairy is a business enterprise established for the harvesting of animal milk—mostly from cows or goats, but also from buffalo, sheep, horses or camels —for human consumption. A dairy is typically located on a dedicated dairy farm or section of a multi-purpose farm that is concerned...
. Sufficient cream is returned to the skimmed milk before sale.
History
Before the advent of centrifugal separators, separation was performed by letting milk sit in a container until the cream floated to the top and could be skimmed off by hand. A variant container-separator had a nozzle at the bottom which was opened to allow the milk to drain off. A window in the side, near the nozzle at the bottom, allowed the operator to observe when the milk was drained. Lehmans Hardware Inc. still sells these.The centrifugal separator was first manufactured by Gustaf de Laval
Gustaf de Laval
Karl Gustaf Patrik de Laval was a Swedish engineer and inventor who made important contributions to the design of steam turbines and dairy machinery.-Life:De Laval was born at Orsa in Dalarna...
, making it possible to separate cream from milk faster and more easily, without having to let the milk sit for a time, and risk it turning sour. Possibly because Gustaf de Laval
Gustaf de Laval
Karl Gustaf Patrik de Laval was a Swedish engineer and inventor who made important contributions to the design of steam turbines and dairy machinery.-Life:De Laval was born at Orsa in Dalarna...
manufactured the first cream separators, many people credit the invention to de Laval. However, many patents appear before his, all of them labelled as 'improvements'. One of the first specifically for cream separation was patented by W. C. L. Lefeldt and C. G. O. Lentsch.
The original centrifugal separators were hand-cranked, as illustrated.
Mechanism
Manual rotation of the separator handle turns a worm gear mechanism which causes the separator bowl to spin at thousands of revolutions per minuteRevolutions per minute
Revolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
.
When spun, the heavier milk is pulled outward against the walls of the separator and the cream, which is lighter, collects in the middle. The cream and milk then flow out of separate spouts. Some floor model separators were built with a swinging platform attached to the stand. The bucket for collecting the cream was put on the platform, and a much larger bucket was set on the floor to collect the milk. Some floor model separators had two swinging platforms. Smaller versions of separators were called table-top models, for small dairies with only a few cows or goats.
Gustaf de Laval's construction made it possible to start the largest separator factory in the world, Alfa Laval AB
Alfa Laval
Alfa Laval AB is a Swedish company, founded in 1883 by Gustaf de Laval and Oscar Lamm. The company is a leading producer of specialized products and solutions used to heat, cool, separate and transport such products as oil, water, chemicals, beverages, foodstuffs, starch and...
. The milk separator represented a significant industrial breakthrough in Sweden. Within the first decade in the 1900s, there were over twenty separator manufacturers in Stockholm
Stockholm
Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...
. Separators in modified form
Separator (oil production)
The term separator in oilfield terminology designates a pressure vessel used for separating well fluids produced from oil and gas wells into gaseous and liquid components. A separator for petroleum production is a large vessel designed to separate production fluids into their constituent components...
are also used on ships to purify oil.
The original design had a manual bowl that required manual cleaning. Most modern separators use a self-ejecting centrifuge bowl that can automatically discharge any sedimentary solids that may be present, and that allow for clean-in-place
Clean-in-place
Clean-in-Place is a method of cleaning the interior surfaces of pipes, vessels, process equipment, filters and associated fittings, without disassembly....
(CIP). The self-draining vessel feature is mandatory for machinery designated for 3A approval (an industrial sanitary standard).