Shirley Trash Analyser

Shirley Trash Analyser

Anshul Matani

Department of Textile Technology

Veermata Jijabai Technological Institute, Mumbai, India

Introduction:

• The measurement of trash or non-lint content is very important in assessing the lint quality of cotton sample .
• The Shirley Analyzer, a laboratory machine developed at the Shirley Institute, Manchester, England, provides an effective means for both quantitative and qualitative analyses of foreign matter in cotton lint .
• The Shirley Analyser separates the trash from the lint with a minimum of fiber loss . This is probably the nearest approach to perfect separation of lint and foreign matter that has yet been developed.

Technical Specifications:

• Sample size : 50 or 100 gms per test
• Measuring Principle : Buoyancy separation principle
• Opening rate of lint : 16 gms per minute
• Micro-dust filtering stage : Fine cotton - 150 micron , Coarse cotton - 300 micron
• Main motor : 1440 rpm
• Suction motor :2880 rpm
• Licker-in speed : 1240 rpm
• Feed roller speed : 26 rpm
• Balance accuracy : ± 0.002 gms
• Control system : Micro-computer based solid-state electrical system control
• Power supply : Three phase 220 Volts AC @ 50 Hz
• Power consumption : ~ 2000 watts
• Applicable standard : ASTM D2812
• Physical Dimensions : Size - 620 mm x 900 mm x 550 mm ; Weight - 180 kgs

Parameters Tested:

• Lint content(L) in weight and percentage
• Trash content(T) in weight and percentage
• Invisible waste(W) in weight and percentage

Features:

• Compact , aerodynamic shape , silent operation and non-polluting nature boosts laboratory environment
• Digital , monitor based and user friendly operating system
• Solid-state controlled electrical system to enhance operator safety

Atmospheric and Sample Conditions:

Standard Testing - 

•  RH = 65 ± 2 %
• Temperature = 27 ± 2 °C 
•  International Testing - ISO 139

Working Principle:

• The Shirley Analyser works on the principle of buoyancy separation (air flotation principle) by air currents .
• The Shirley analyzer consists of a feed roller, licker- in, the cylinder and a blower to open the fibers and separate lint and trash.
• The cotton is fed slowly to the lickerin and, as it is broken up, the air blast carries the lint around the bottom of the flow plate and up to the condenser.
• Trash and heavy particles drop into the waste chamber.
• The machine is so constructed that not only raw cotton but also various waste products can be analyzed.
• The working is similar that of a miniature carding machine.

Procedure:

• Clean the instrument and the containers
• Shake the specimen so that large particles of foreign matter i.e. husk , leaves , stem particles , metal particles etc (which may otherwise damage the machine) are removed from the specimen. Keep these droppings separately.
• Open out the hard lumps of fibers, if present
• Spread the specimen on the feed plate in the form of an even layer
• Start the machine and let the trash and lint collect in their respective compartments
• Take out the lint from the lint chamber and pass it again through the machine without disturbing the discarded matter in the settling chamber
• Stop the machine and collect the lint (L1) from the lint chamber and keep it in a separate container
• Remove all the discarded particles containing lint from the tray and settling chamber and pass it through the machine.
• Collect the lint (L2) and keep it in a separate chamber. Collect all the discarded matter (T1) in the tray, settling chamber and any seeds clinging to the wires of the licker– in the cylinder and combine them
• Weigh the discarded matter (T1) (to an accuracy of 100 mg and if the weight is less than 10g, weight to an accuracy of 10 mg), which contains lint again through the machine and ignore the discarde matter collecte . Collect the lint (L3) and keep it in a separate container. Weigh the lint (L3) to an accuracy of 10 mg
• Combine all the portions of lint (L1, L2, and L3) and weight to an accuracy of 10 mg.

Tabulation:

Sr. No.	Sample wt.(gms)	Lint Content (gms)	Trash Content (gms)	Invisible waste (gms)	Trash %
1.
2.
3.
Min.
Max
Avg

Calculations:

• Lint content (L)% = [(L1+ L2+ L3) ÷ M] × 100
• Trash content (visible waste) (T)% = [(T1 – L3) ÷ M] × 100
• Invisible waste content (W)% = 100 – (L+T)

Results:

• Lint percentage –                              
• Trash percentage –                           
• Invisible loss –