Podcast
Questions and Answers
What is the relationship between mesh number and mesh size?
What is the relationship between mesh number and mesh size?
What is the primary purpose of sieve analysis?
What is the primary purpose of sieve analysis?
What is the appropriate arrangement of sieves during the testing method?
What is the appropriate arrangement of sieves during the testing method?
What is 'cumulative weight percentage passing' in sieve analysis?
What is 'cumulative weight percentage passing' in sieve analysis?
Signup and view all the answers
What are mesh numbers used for in sieve cloth?
What are mesh numbers used for in sieve cloth?
Signup and view all the answers
During sieve analysis, why might hand sieving be performed after using a sieve shaker?
During sieve analysis, why might hand sieving be performed after using a sieve shaker?
Signup and view all the answers
What does an increase in mesh number indicate concerning the size of the apertures?
What does an increase in mesh number indicate concerning the size of the apertures?
Signup and view all the answers
What is a key function of the pan or receiver placed below the bottom sieve?
What is a key function of the pan or receiver placed below the bottom sieve?
Signup and view all the answers
Which size measurement method involves the use of optical or electron microscopy?
Which size measurement method involves the use of optical or electron microscopy?
Signup and view all the answers
What does the equivalent diameter of an irregular particle represent?
What does the equivalent diameter of an irregular particle represent?
Signup and view all the answers
Which of the following is NOT a characteristic diameter used in size measurement?
Which of the following is NOT a characteristic diameter used in size measurement?
Signup and view all the answers
What is the primary purpose of using microscopy in size analysis?
What is the primary purpose of using microscopy in size analysis?
Signup and view all the answers
Which size measurement method employs techniques like laser diffraction and acoustic attenuation?
Which size measurement method employs techniques like laser diffraction and acoustic attenuation?
Signup and view all the answers
In sedimentation, which diameter refers to a spherical particle having the same settling velocity as the particle under Stokesian conditions?
In sedimentation, which diameter refers to a spherical particle having the same settling velocity as the particle under Stokesian conditions?
Signup and view all the answers
Which of the following measurement methods includes techniques like sieving and impaction?
Which of the following measurement methods includes techniques like sieving and impaction?
Signup and view all the answers
What is the diameter of a particle that shares the same volume as the irregular particle called?
What is the diameter of a particle that shares the same volume as the irregular particle called?
Signup and view all the answers
Flashcards
Visual Methods in Size Measurement
Visual Methods in Size Measurement
Methods using visual tools like microscopes, to determine particle size.
Optical Microscopy Size Range
Optical Microscopy Size Range
Measurements of particle sizes between 3-1000 m using light microscopes.
Equivalent Diameter
Equivalent Diameter
Diameter of a sphere having the same characteristic (e.g., volume, surface area) as an irregularly-shaped particle.
Volume Diameter (dv)
Volume Diameter (dv)
Signup and view all the flashcards
Surface Diameter (ds)
Surface Diameter (ds)
Signup and view all the flashcards
Test Sieve
Test Sieve
Signup and view all the flashcards
Separation Methods (Size Measurement)
Separation Methods (Size Measurement)
Signup and view all the flashcards
Microscopy Size Analysis
Microscopy Size Analysis
Signup and view all the flashcards
Sieve Cloth
Sieve Cloth
Signup and view all the flashcards
Mesh Number
Mesh Number
Signup and view all the flashcards
Mesh Size
Mesh Size
Signup and view all the flashcards
Sieve Analysis
Sieve Analysis
Signup and view all the flashcards
Differential Analysis
Differential Analysis
Signup and view all the flashcards
Cumulative Weight Percentage Retained
Cumulative Weight Percentage Retained
Signup and view all the flashcards
Cumulative Weight Percentage Passing
Cumulative Weight Percentage Passing
Signup and view all the flashcards
Study Notes
Size Measurement Methods
- Methods and instruments for size measurement are categorized into six groups for simplicity.
- Visual methods: Optical, electron, and scanning electron microscopy, image analysis.
- Separation methods: Sieving, classification, impaction, electrostatic differential mobility.
- Stream scanning methods: Electrical resistance zone, optical sensing zone measurements.
- Field scanning methods: Laser diffraction, acoustic attenuation, photon correlation spectroscopy.
- Sedimentation and Surface methods: Permeability and adsorption.
Visual Methods: Microscopy
- Microscopy is used alongside other size analysis methods to determine the size range and degree of dispersion.
- It's the only method that allows visualization of individual particles.
- Common measurement ranges include:
- 3-1000 µm for optical microscopy
- 2 nm to 1 µm for Transmission Electron Microscopy (TEM)
- 20 nm to 1000 µm for Scanning Electron Microscopy (SEM)
Equivalent Diameter
- Defining the size of irregularly shaped particles is done by comparison with standard shapes, usually spheres.
- Volume diameter (dv): The diameter of a sphere having the same volume as the irregular particle. Formula: dv = (6Vp/π)1/3 = 1.241Vp1/3
- Surface diameter (ds): The diameter of a sphere having the same surface area as the irregular particle. Formula: ds= (4Ap/π)1/2= 0.564Ap1/2
- Stokes' diameter: The diameter of a sphere having the same settling velocity as the particle under Stokesian conditions.
- Newton's diameter: The diameter of a sphere having the same settling velocity as the particle under Newtonian conditions.
Separation Methods: Sieving
- Test sieves are circular brass shells used to separate particles based on size.
- Sieve cloth made of wire with uniform square openings for separation.
- Aperture (or Opening): Distance between parallel wires.
- Mesh number: Number of apertures per linear inch.
- Mesh size: Distance between wires. Mesh number and mesh size are inversely related. (Higher mesh number, smaller mesh size)
- Sieve analysis: A mineral processing method where particles are separated based on size.
- Procedure:
- Arrange sieves into a nest (coarsest to finest).
- Place the material to be tested on the topmost sieve.
- Shake the sieves to allow particles to pass through.
- Weigh the material retained on each sieve.
- Calculate the percentage of material retained on each sieve to produce the differential analysis.
Particle Size Distribution Data
- Particle sizes are often measured and reported in tabular format (e.g., Table 1).
- Weight percentages of retained material on each sieve are calculated for differential analysis.
- Cumulative weight percentages are obtained by sequentially adding the individual weight percentages from either top or bottom of the table.
- Mean particle sizes for each fraction are calculated (e.g., Table 2). Formula for calculating average size: Average size = 100/Σ (widi), where wi is the weight percent of the material retained by the sieve, and di is the mean size of the material retained by the same sieve.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on various size measurement methods including visual, separation, stream scanning, and field scanning techniques. This quiz covers essential instruments used for size analysis, with a focus on microscopy and its applications. Challenge yourself to understand the methods and their respective measurement ranges.
