Rittinger’s Law — The energy required for reduction in particle size of a solid is directly proportional to the increase in surface area. … As noted by Ehmer, there is an inverse relationship between size and strength of particles: as particles get smaller, their strength increases.
What is d10 D50 and d90? d10, d50 and d90 are so-called percentile values. These are statistical parameters that can be read directly from the cumulative particle size distribution. They indicate the size below which 10%, 50% or 90% of all particles are found.
Likewise What is Kick’s theory?
The Kick’s law states that the energy required to reduce the size of particles is proportional to the ratio of the initial size of a typical dimension (for example the diameter of the particles) to the final size of that dimen- sion. This relation is derived directly form the elasticity theory of ideal brittle solids.
What is the purpose of comminution? Within industrial uses, the purpose of comminution is to reduce the size and to increase the surface area of solids. It is also used to free useful materials from matrix materials in which they are embedded, and to concentrate minerals.
What is rittinger’s number?
Rittinger’s number designates the new surface created per unit mechanical energy absorbed by the material being crushed.
What is granulometry test? Granulometry is the measurement of the size distribution in a collection of grains. It is also called particle size distribution test. It is often characterized by the percentage of particles with certain diameter ranges (in micron meters). You can often find it in the section 9 of a safety data sheet (SDS).
What is D90 in particle size distribution?
D90: The portion of particles with diameters below this value is 90%. Volume percentage: The highest volume percentage of the particle size distribution displayed.
What does D50 particle size mean? The D50 is the size in microns that splits the distribution with half above and half below this diameter. The Dv50 (or Dv0. 5) is the median for a volume distribution, Dn50 is used for number distributions, and Ds50 is used for surface distributions.
What are the advantages of size reduction?
Advantages of size reduction Content uniformity Uniform flow Effective drying Increases surface area or viscosity Uniform mixing and drying Improve rate of absorption . Smaller the particles greater is absorption. Improve dissolution rate.
What is fluid energy mill? The jet mill, also called the fluid-energy mill, is based on a cold stream impact process in which the materials are disintegrated by the collision of a particle with a particle, a stationary target, or a wall of the containing chamber. The collision energy is generated by a high-speed jet flow.
What are the principles of size reduction?
Principles of Size Reduction – Solid Foods
- Size reduction is a unit operation involving such activities as cutting, slicing, milling or pulping of food. …
- The three types of forces involved in size reduction of solids are compression, impact and shear.
What is the process of comminution? Comminution is a process of reducing the size of ore particles to liberate the minerals in preparation for extraction in downstream processes, and classification is installed to ensure that liberated minerals enter the recovery section of the process plant and those not ready are recycled.
What is comminution in pharmaceutical engineering?
Size reduction is a process of reducing large solid unit masses – vegetables or chemical substances into small unit masses, coarse particles or fine particles. Size reduction is commonly employed in pharmaceutical industries. Size reduction process is also referred to as Comminution and Grinding.
What is comminution circuit? A comminution circuit optimisation typically involves a circuit audit and collection of crushing and grinding circuit survey data. This includes an inventory of major equipment sizes and operating conditions.
What is rittinger’s law formula?
Equation (11.3) is known as Rittinger’s Law. As the specific surface of a particle, the surface area per unit mass, is proportional to 1/L, eqn. … (11.4) and so Ei is the amount of energy required to reduce unit mass of the material from an infinitely large particle size down to a particle size of 100 mm.
Which of the following equation is rittinger’s law? Correct Answer: ratio of feed opening to discharge opening.
In what situation and factors rittinger’s law is best applicable?
Rittinger’s law is applicable mainly to that part of the process where new surface is being created and holds most accurately for fine grinding where the increase in surface per unit mass of material is large.
What is the procedure of sieve analysis? Step 1: Take a representative oven-dried sample that weighs approximately 500g. Step 2: If particles are lumped or conglomerated, crush the lumps but not the particles using the pestle and mortar. Step 3: Determine the mass of sample accurately – Weight (g). Step 4: Prepare a stack of test sieves.
Is sieve A analysis?
A sieve analysis is an analytical technique used to determine the particle size distribution of a granular material with macroscopic granular sizes. The sieve analysis technique involves several layers of sieves with different grades of sieve opening sizes.
What is coefficient of uniformity?
uniformity coefficient (u-ni-form’-i-ty). A numerical expression of the variety in particle sizes in mixed natural soils, defined as the ratio of the sieve size through which 60% (by weight) of the material passes to the sieve size that allows 10% of the material to pass.
What is D10 soil? D10 is called as effective particle size. This means that 10% percent of the particles are finer and 90% of the particles are coarser than D10. This is the size at 10% finer by weight. Similarly, D60 is the particle size at which 60% of the particles are finer and 40% of the particles are coarser than D60 size.
What is Malvern particle size analyzer?
The Malvern Mastersizer 3000 is a laser diffraction particle size analyzer, suitable for measuring particle sizes 0.1 um – 3 mm. … (Small particles have a small scattering angle, while large particles have a large scattering angle.) Using Mie theory, the data is used to calculate particle size distribution in a sample.