CRYOGENIC GRINDING 1

2 OBJECTiVES INTRODUCTION PROBLEMS IN CONVENTIONAL GRINDING WORKING ADVANTAGES OF CRYO GRINDING EXPERIMENTAL STUDIES APPLICATION

CRYOGENICS The term “ Cryogenics” originated from the Greek word which means creation or production by means of cold. Cryogenics is the study of very low temperatures or the production of the same.. Liquid nitrogen is the most commonly used element in cryogenics and is legally purchasable around the world. 3

APPLICATIONS OF CRYOGENICS In Gas Industry In Gas Industry As the source of gas As the source of gas As Rocket propellant As Rocket propellant In Biology In Biology In Food Industry In Food Industry In Electronics In Electronics In Medicines In Medicines In Grinding In Grinding 4

GRINDING The process is carried out with a grinding wheel made up of grits for removing materials from work piece surface. Grinding can be classified into two types 5 Grinding for material removal Grinding for powdering

PROBLEMs IN CONVENTIONAL GRINDING PROCESS High heat generation Introduction of tensile residual stress Less tool life Clogging and Gumming of the mill Oxidation Loss of Etheric oil in Spice grinding 6

Now….elimination of all these problems are required…….. But………. HOW..??? 7

Here comes the necessity of CRYOGENIC GRINDING ….. also known as Freeze Grinding 8

Cryogenic grinding involves cooling a material below its embrittlement temperature with cryogenic fluid. Typically Liquid Nitrogen or in certain applications, liquid Carbon Dioxide is used. CRYOGENIC GRINDInG 9

This process has several benefits Ability to process soft or elastic material Increased productivity Low Power Consumption Smaller size particle Minimal loss of volatile component 10

WORKING 1106/09/2010

ADVANTAGES OF CRYOGRINDING Increased throughput & power saving Finer particle size More uniform particle distribution Lower grinding cost No heat generation Provides an inert atmosphere Reduced grinding force Provide clean and pollution free environment Prevent oxidation Possibility of fine grinding of difficult spices 12

SL No. ComponentsCryoground(%) Conventional ground(%) 1Moisture Volatile oil Flavour compounds (relative concentration) Alpha pinene limonene RESULTS OF EXPERIMENTAL STUDIES 1. Volatile oil content & flavor component Example : pepper 13

2. Throughput of the mill Current required =6A Working temperature =50°C Throughput of conventional grinding =22kg/hr Throughput of cryogenic grinding =50kg/hr i.e. throughput for cryogenic grinding is 2.25 times more than conventional grinding 14

APPLICATION OF CRYO-GRINDING recycling of composite materials Thermoplastics Thermo sets Adhesives & waxes Explosives Spices 15

Hence we can conclude ….. 16

Thank you … 17

QUESTIONS ? ? 18