Centrifugal spray drying technology in the late 50's in the domestic dairy industry began to use, has a history of over 40 years. At present the national dairy industry about 5% manufacturers to adopt this technology. It is to promote the rapid development of China's dairy industry has played a positive role.

1 centrifugal spray drying was born

In the dairy industry in our country is first applied by spray drying technique is" pressure" and" the two fluid" technology, at that time because of the technological level and production scale and other factors limit, only is horizontal, level, spray form, its evaporation capacity most in 250kg / h below. In 60 time metaphase, Anderson dairy factory installed a evaporation 350kg / h horizontal pressure spray drying equipment, spray head 7; 1967 to aid Albania, provided by the spray drying equipment is the imitation of the southern suburbs of Beijing dairy factory in 1965 from Japan to introduce the evaporation of 350kg / h double nozzle, horizontal, pressure spray dryer, requirements of evaporation 150kg / h, also use double nozzle; Shanghai of 60 time end milk crystal three plants were first installed vertical pressure spray dryer, its evaporation rate is 250kg / h, head still did not less than 3. The spray of the heat, is a kind of wrong theory prevailed. Many people think that the diameter of the nozzle is not greater than a certain value, otherwise, the material cannot be atomized. At the time of equipment capacity is small, the applicator, Chengdu inevitably made small aperture nozzle production, the smallest diameter of nozzle 0.5mm only, this to the production operation management, caused many problems, mainly the milk powder particle is small, the disperal is poor, color, tissue state nor for users.

In order to solve this problem, many manufacturers, research institutes, universities and colleges from the aspects of looking for the production of good soakage of instant milk powder", appeared in succession" two stage drying method"," add lactose recrystallization method" and the trial production, but the end result of high cost, is not suitable for large-scale continuous production can not be extended. At the same time, appearance of centrifugal spray drying technology, and gets certain development, the main reason is that the indigenous to produce centrifugal spraying machine low speed, only 5000r / MIM ), as the line speed is low, squirting milk powder particles, the disperal is better than pressure spray products, in the market relatively popular with users. Until the late 70's centrifugal spray drying of milk powder in the market dominant position. At that time, several representative milk factory is Songhua River dairy factory, Cha hayang dairy factory, the western suburbs of Beijing dairy factory, Hajime Millhauser dairy factory.

2 centrifugal spray drying of recession

In 1980 Heilongjiang province dairy machinery plant design of evaporation amount 250kg / h single nozzle vertical pressure spray drying device ten, 1982 in Tailai County dairy plant put into normal operation, thereafter, new, expansion of the dairy plant using centrifugal drying technology is gradually reduced, some have used centrifugal spray technology of the old plant, expansion began with a pressure spray technology, manufacturers do not consider two kinds of technology and management on the inconvenience, such as rich county milk crystal factory, dairy products factory in Zhaodong, the western suburbs of Beijing dairy factory, dairy products factory in Hulan, the song station dairy factory. Some centrifugal spray technique has been used for many years of the old plant, the new installation of pressure spray drying equipment, the original centrifugal spray drying equipment deactivated or simply removed, such as dairy products factory in Zhaodong, the western suburbs of Beijing dairy factory; since 80 time end, appeared " centrifugal" instead of " pressure" phenomenon, the successful transformation of the rich dairy factory, Songhua Lake dairy factory, song station dairy factory and JuLang pasture dairy products factory. These phenomena, people have gradually recognized the" centrifugal spray"

And" spray", centrifugal spray drying technology in China's dairy industry market has been shaken, pressure spray drying technology has an absolute advantage in ten, can say" centrifugal spray" in China's dairy industry has begun to decline. Two kinds of advantages and disadvantages of the methods of debate has been rarely heard, never again to hear the" centrifugal" milk than" pressure" certainly good quality statement.

This change come, analysing the reasons why there are many factors. Mainly has the following several points:

( 1) the theoretical misunderstandings

Denmark K Ma Si Toth." Spray drying Handbook" clearly pointed out the centrifugal spray drying method is suitable for the production of fine grain products. Some people because we can not build high speed centrifugal sprayer, and the bad atomization in the case of the production of larger particles of powdered milk is mistaken for the advantages of centrifugal spray.

( 2) the centrifugal spray drying equipment design specification

From the time of 50-80, industry of our country milkings using centrifugal spray drying equipment, almost out of" self-taught expert" hand, no standard design. In order to less investment, quick start, centrifugal sprayer is mostly " Earth", all kinds of hot air distributor, uneven wind inlet, is unable to adjust, there exists" coke" problem, a few to no one to reach design capacity, resulting in and before the process is not complete.

( 3) in milk powder production raw material characteristics

Milk powder is the main raw material for milk, the milk sugar, additives such as eliminating