History of Pneumatic Conveyors:
The basic Principles of Pneumatic conveying stated by Great Alexander in 100 BC itself. In pre historical age Romans used Water supply pipelines and sewage disposable systems. Chinese conveyed Natural gas through Bamboo’s. These are the evidence for transporting physical objects in Pneumatic tubes.
The first industrial application of pneumatic conveying was probably in the form of capsule transportation system in which materials are enclosed in cylindrical or spherical capsules of diameter only slightly less than that of the pipe line and then use the gas or liquid to propel the capsules from one end of the pipe line to the other. The first pneumatic capsule system was built and demonstrated in England in 1820’s by John Vallance. Considerable work on pneumatic capsule transport was undertaken by Pneumatic Despatch Company who laid an experimental tube, about 400 meters in length, along the bank of the river THAMES in London. Various similar tunnels and capsule systems were constructed in England to carry letters and parcels. Attempts were made in London and New York around 1860’s to use pneumatic capsule systems to carry passengers, but these attempts proved unsuccessful due to practical difficulties with human load. In 1864, Pneumatic railway line was built in Crustal palace to move a carriage, which had been fitted with a sealing diaphragm.
In 1847, Peugeot plant in France used pneumatic conveying plant for exhaust dust from number of grind stones with the help of an exhaust fan
It was in 1866 that a demonstration was arranged by B.E. Startevant to show that solid particles can also be conveyed directly by a stream of air through a pipeline. The first experimental type of pneumatic conveyors were fan driven vacuum systems employed to transport food grains and sawdust. From the early years of 20th century high pressure air was employed in pneumatic conveying. In mid 1920’s the technique of fluidisation discovered and since then the technology of pneumatic conveying has grown enormously since 1970’s because of its suitability for modern industrial processes and economies of bulk handling methods. During the first World War, the development of pneumatic conveying was influenced by the high demand for foods, labour scarceness and risks of explosion. Since the pneumatic conveying systems were seen as the answer for those situations, so a huge evolution of pneumatic transport was achieved during that time period. In the post war period, pneumatic conveying systems were used for more industrial related materials like coal and cement. Beginning of theoretical approaches, invention of blowers, introduction of batch conveying blow tanks etc., were among the highlighted milestones of the evolution of pneumatic transport systems during the era.
Now-a-days, pneumatic handling of solids is common place in industries like pharmaceutical, cement, food, chemical, glass, plastic and mining etc. Some industries have transport objects for the distance of more than 40 km, material flow rate of few hundred tons per hour and solid loading ratio of more than 500 also possible.