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. The size reduction process is also referred to as Comminution and Grinding.
The document discusses size reduction techniques. It defines size reduction as reducing substances to smaller particles through mechanical means like milling. The objectives of size reduction include improving drug dissolution and absorption. Size reduction is achieved through mechanisms like cutting, compression, impact and attrition. Factors that affect size reduction include the material properties, product requirements, and safety and economic considerations. Common equipment for size reduction discussed are hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills.
Introduction
Objectives
Methods of size reduction
Advantages of size reduction
Disadvantages of size reduction
Mechanism of size reduction
Laws governing to the size reduction
Principle of Size Reduction, Construction, working and uses of following-
Hammer mill
Ball mill
Fluid Energy Mill
Edge Runner Mill
End Runner Mill
This document discusses size reduction, which is the process of decreasing the size of particles through mechanical means. It defines size reduction and describes various factors that affect the process, such as hardness, moisture content, and material structure. Several common size reduction methods are also outlined, including hammer mills, ball mills, roller mills, and colloidal mills. The key theories relating to energy input and particle size are explained as well. Overall, the document provides an overview of size reduction techniques and considerations.
Size reduction is the process of reducing larger particles into smaller particles using external forces. The key mechanisms of size reduction are cutting, compression, impact, attrition, and a combination of impact and attrition. Different types of mills use these mechanisms, including hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills. Factors like hardness, toughness, stickiness, softening temperature, and moisture content affect how easily a material can undergo size reduction. Laws of Rittinger, Kick, and Bond govern the energy requirements for size reduction.
Generally, size reduction and size separation are combined to obtain powder with the desired particle size distribution (PSD) for acceptable flow and compressibility for downstream processing . The mechanical process of reducing the particle size of a solid is also called milling.
This document discusses various methods of size reduction used in pharmaceutical engineering. It begins by defining size reduction as reducing the size of larger particles into smaller particles of a desired size and shape using external forces. It then outlines objectives like increasing surface area and achieving intimate mixing. Mechanisms of size reduction discussed include impact, compression, attrition and cutting. Theories on energy requirements for size reduction include Rittinger's, Kick's and Bond's theories. Common size reduction equipment described are hammer mills, ball mills, fluid energy mills, edge runner mills and end runner mills. Advantages and disadvantages of each method are provided.
This document discusses mixing theory and equipment used for mixing in the pharmaceutical industry. It begins by defining mixing and classifying mixing into different types including mixing of solids, liquids, and semisolids. It then describes various mechanisms of mixing solids including convective, shear, and diffusion mixing. Key factors that influence mixing of solids like particle properties and interparticle forces are explained. Common equipment for mixing solids in small and large scale are then outlined including tumble blenders, V-cone blenders, double cone blenders, and those with mixing blades. Parameters for effective mixing and evaluating mixing are also summarized.
This document discusses size reduction, which is the process of reducing larger particles into smaller particles of a desired size and shape using external forces. It defines size reduction and comminution, and lists the objectives of size reduction such as increasing surface area and achieving intimate mixing. The document describes various size reduction mechanisms, factors affecting size reduction, and theories related to the energy required. It provides details on different size reduction equipment like hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills.
The document discusses size reduction techniques. It defines size reduction as reducing substances to smaller particles through mechanical means like milling. The objectives of size reduction include improving drug dissolution and absorption. Size reduction is achieved through mechanisms like cutting, compression, impact and attrition. Factors that affect size reduction include the material properties, product requirements, and safety and economic considerations. Common equipment for size reduction discussed are hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills.
Introduction
Objectives
Methods of size reduction
Advantages of size reduction
Disadvantages of size reduction
Mechanism of size reduction
Laws governing to the size reduction
Principle of Size Reduction, Construction, working and uses of following-
Hammer mill
Ball mill
Fluid Energy Mill
Edge Runner Mill
End Runner Mill
This document discusses size reduction, which is the process of decreasing the size of particles through mechanical means. It defines size reduction and describes various factors that affect the process, such as hardness, moisture content, and material structure. Several common size reduction methods are also outlined, including hammer mills, ball mills, roller mills, and colloidal mills. The key theories relating to energy input and particle size are explained as well. Overall, the document provides an overview of size reduction techniques and considerations.
Size reduction is the process of reducing larger particles into smaller particles using external forces. The key mechanisms of size reduction are cutting, compression, impact, attrition, and a combination of impact and attrition. Different types of mills use these mechanisms, including hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills. Factors like hardness, toughness, stickiness, softening temperature, and moisture content affect how easily a material can undergo size reduction. Laws of Rittinger, Kick, and Bond govern the energy requirements for size reduction.
Generally, size reduction and size separation are combined to obtain powder with the desired particle size distribution (PSD) for acceptable flow and compressibility for downstream processing . The mechanical process of reducing the particle size of a solid is also called milling.
This document discusses various methods of size reduction used in pharmaceutical engineering. It begins by defining size reduction as reducing the size of larger particles into smaller particles of a desired size and shape using external forces. It then outlines objectives like increasing surface area and achieving intimate mixing. Mechanisms of size reduction discussed include impact, compression, attrition and cutting. Theories on energy requirements for size reduction include Rittinger's, Kick's and Bond's theories. Common size reduction equipment described are hammer mills, ball mills, fluid energy mills, edge runner mills and end runner mills. Advantages and disadvantages of each method are provided.
This document discusses mixing theory and equipment used for mixing in the pharmaceutical industry. It begins by defining mixing and classifying mixing into different types including mixing of solids, liquids, and semisolids. It then describes various mechanisms of mixing solids including convective, shear, and diffusion mixing. Key factors that influence mixing of solids like particle properties and interparticle forces are explained. Common equipment for mixing solids in small and large scale are then outlined including tumble blenders, V-cone blenders, double cone blenders, and those with mixing blades. Parameters for effective mixing and evaluating mixing are also summarized.
This document discusses size reduction, which is the process of reducing larger particles into smaller particles of a desired size and shape using external forces. It defines size reduction and comminution, and lists the objectives of size reduction such as increasing surface area and achieving intimate mixing. The document describes various size reduction mechanisms, factors affecting size reduction, and theories related to the energy required. It provides details on different size reduction equipment like hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills.
The document discusses double cone mixers, which are used to homogenously mix different materials. They work by tumbling materials inside a revolving vessel. Key points:
- Double cone mixers are used in industries like food, pharmaceuticals, chemicals, and minerals to mix ingredients like APIs, starches, flavors, and spices.
- They consist of two conical sections welded to a central cylinder and rotate about an axis perpendicular to the cone axes. Mixing occurs as materials move through the different sections.
- They are available in batch sizes from 50 liters to 3500 liters and include features like adjustable paddles, discharge valves, safety guards, and variable speed control.
-
This document discusses various methods of size reduction. It defines size reduction as reducing the size of larger particles into smaller particles of a desired size and shape using external forces. The objectives of size reduction are listed as increasing surface area, separating constituents, achieving intimate mixing, improving handling characteristics, and facilitating disposal of solid wastes. Common size reduction mechanisms are impact, compression, attrition, and cutting. Factors that affect size reduction include properties of the materials, energy requirements, and theories like Rittinger's, Bond's, and Kick's. Common size reduction equipment discussed are hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills.
This document discusses size reduction, which is the process of reducing substances into smaller pieces or particles through mechanical means. It describes the objectives and mechanisms of size reduction and factors that affect the process. Several common size reduction machines are also outlined, including their principles, construction, uses, advantages, and disadvantages. Size reduction is an important pharmaceutical process that improves properties like dissolution rate and bioavailability by increasing surface area.
This document discusses various methods for size separation of powders, as outlined in the Indian Pharmacopoeia. It describes 5 grades of powder sizes defined by the IP based on their ability to pass through various mesh sieves. Common separation techniques include sieving, cyclone separation, air separation, and elutriation. Sieving involves using a set of sieves arranged from largest to smallest mesh size to separate powder fractions. Cyclone and air separators use centrifugal forces to separate solids from gases. Elutriation separates powders based on particle density differences in a moving fluid.
objectives, applications, mechanism of size separation, the official standard of powders, sieves, sieve shaker, cyclone separator, air separator, bag filter, elutriation tank
The spray dryer uses a stream of hot gas to rapidly dry liquid materials into fine particles or powder. The liquid is atomized and sprayed into a drying chamber where it contacts the hot gas, drying the droplets. The dried particles are then collected in a cyclone separator. Spray drying is useful for heat-sensitive materials and allows for continuous, rapid drying to produce uniform, spherical particles. However, spray dryers are bulky, expensive to operate, and have low thermal efficiency.
The document discusses a hammer mill, which reduces particle size through repeated impacts using rotating hammers. It has various pharmaceutical uses including grinding raw materials and excipients. A hammer mill works by feeding materials into a chamber containing rapid rotating hammers that fracture particles through collisions. Properly sized particles pass through screens while larger ones require further grinding. Key advantages are rapid grinding and easy control of particle size. Disadvantages include potential heat damage and susceptibility to foreign objects in the feed.
Size reduction, or comminution, is the process of reducing substances into smaller pieces or fine powder. It increases the surface area, allowing for faster dissolution and extraction of active constituents. The degree of size reduction depends on factors like the drug's hardness, solvent used, and extraction process. Various size reduction methods include cutting, compression, impact, and attrition. Common mills are the cutter mill, roller mill, hammer mill, ball mill, and fluid energy mill. Levigation involves wet grinding while elutriation separates fine and coarse particles.
Size reduction is the process of decreasing the physical dimensions of objects or materials by breaking them into smaller pieces. It is done by applying external forces to break larger particles into smaller ones. The main objectives of size reduction are to increase surface area for reactions, separate materials, improve handling and mixing. Some common size reduction methods are impact, compression, shear and attrition. Key factors that affect size reduction are the material's hardness, structure, abrasiveness, softening temperature and moisture content. Several theories describe the energy required for size reduction, including Rittinger's, Bond's and Kick's theories. Only about 10% of the total energy input is actually used to reduce particle size.
This document discusses mixing and homogenization processes. It defines mixing as combining two or more substances together, and identifies perfect mixing as each particle of one material lying adjacent to a particle of the other material. The objectives of mixing are outlined. There are three types of mixtures discussed: positive, negative, and neutral. The mechanisms and equipment used for mixing powders, liquids, and semi-solids are described. Homogenization is defined as preparing a fine emulsion from a coarse one by converting large globules to small globules. Common homogenization equipment like hand homogenizers, Silverson mixers, and colloidal mills are summarized.
Mixing is a general term that includes stirring, beating, blending, binding, creaming, whipping, and folding. In mixing, two or more ingredients are evenly dispersed in one another until they become one product.
Size reduction is a process of reducing large solid unit masses, coarse particles or fine particles.
Size reduction may be achieved by two methods:
1] Precipitation
2] Mechanical process
1] Precipitation method: Substance is dissolve in appropriate solvent.
2] Mechanical process: Mechanical force is introduce by using different equipments like ball mill, colloid mill etc.
Size reduction is the process of reducing the particle size of a substance through mechanical means like grinding or milling. It has several objectives like increasing surface area, improving mixability and compressibility. Factors like hardness, toughness, abrasiveness affect size reduction. Common mechanisms are cutting, compression, impact and attrition. Equipment used include colloid mill, hammer mill, ball mill and jet mill which work on different principles to produce fine particles.
The document discusses various methods of size reduction or comminution. It describes different types of mills used for size reduction including hammer mill, ball mill, colloid mill, and fluid energy mill. The objectives of size reduction are to reduce particle size, increase surface area, improve handling and flow of powders. Factors affecting size reduction include hardness, toughness, moisture content and specific mills are described such as how a cutter mill uses cutting blades and a ball mill uses grinding balls to reduce particle size.
This document discusses size separation techniques used in the pharmaceutical industry. It begins by defining size separation as the process of separating particles into different sizes using screening surfaces. Some common objectives of size separation are to classify materials by size, control size variation, and enhance product performance. Sieves are the most common screening devices and come in various materials and constructions like woven wire, punched plates, and bolting cloth. Key size separation techniques discussed are agitation, brushing, and centrifugal motion, which use vibration, rotation, or air flow to move particles through sieves.
The document discusses size reduction techniques used in pharmaceutical engineering. It describes the hammer mill and ball mill, which use mechanical forces for size reduction. The hammer mill works by impact between rapidly moving hammers and powder materials, while the ball mill uses impact and attrition between rapidly moving balls inside a rotating cylinder. Both provide descriptions of their basic principles, constructions, operating parameters, advantages and disadvantages.
This document discusses various size reduction equipment, including hammer mills, ball mills, and disintegrators. It provides advantages and disadvantages of hammer mills, such as their ability to control particle size but potential for heat buildup. Ball mills are described as using impact between rapidly moving balls and material to reduce size. Key advantages are their ability to produce fine powder and handle wet or dry materials. Disintegrators work via impact of fast-spinning beaters inside a drum and are useful for reducing very hard drugs to a fine powder.
This document summarizes a presentation on wet granulation equipment. It describes the process of wet granulation which involves adding a liquid solution to powders to form granules. It then discusses various types of equipment used in wet granulation including rapid mixing granulators, fluidized bed dryers, vibratory sifters, multi mills, and double cone blenders. For each type of equipment, it provides details on its working principles, components, parameters to control, and advantages.
The document discusses three main modes of size reduction: cutting, compression, and impact. Cutting involves using sharp blades to cut fibrous and waxy materials, like in a cutter mill. Compression crushes soft materials between rollers through applied pressure, as in a roller mill. Impact involves high-speed hammers or bars splitting materials apart on impact, making it suitable for all drugs. Examples of impact mills are fluid energy mills and ball mills. Attrition breaks down brittle drugs through rubbing action between surfaces, as also seen in fluid energy and ball mills.
Size reduction, process of size reduction, size reduction a topic of pharmac...RajkumarKumawat11
Size reduction, process of size reduction, size reduction a topic of pharmaceutics, cutter mill, roller mill, hammer mill, ball mill, fluid energy mill, the disintegrator, mills used in pharmaceutical process
Size reduction is a vital unit operation in pharmaceutical manufacturing that involves reducing the size of solid materials to enhance their dissolution properties, improve bioavailability, and facilitate further processing. It is a fundamental step in drug formulation and is employed in various dosage forms like tablets, capsules, and powders.
The document discusses double cone mixers, which are used to homogenously mix different materials. They work by tumbling materials inside a revolving vessel. Key points:
- Double cone mixers are used in industries like food, pharmaceuticals, chemicals, and minerals to mix ingredients like APIs, starches, flavors, and spices.
- They consist of two conical sections welded to a central cylinder and rotate about an axis perpendicular to the cone axes. Mixing occurs as materials move through the different sections.
- They are available in batch sizes from 50 liters to 3500 liters and include features like adjustable paddles, discharge valves, safety guards, and variable speed control.
-
This document discusses various methods of size reduction. It defines size reduction as reducing the size of larger particles into smaller particles of a desired size and shape using external forces. The objectives of size reduction are listed as increasing surface area, separating constituents, achieving intimate mixing, improving handling characteristics, and facilitating disposal of solid wastes. Common size reduction mechanisms are impact, compression, attrition, and cutting. Factors that affect size reduction include properties of the materials, energy requirements, and theories like Rittinger's, Bond's, and Kick's. Common size reduction equipment discussed are hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills.
This document discusses size reduction, which is the process of reducing substances into smaller pieces or particles through mechanical means. It describes the objectives and mechanisms of size reduction and factors that affect the process. Several common size reduction machines are also outlined, including their principles, construction, uses, advantages, and disadvantages. Size reduction is an important pharmaceutical process that improves properties like dissolution rate and bioavailability by increasing surface area.
This document discusses various methods for size separation of powders, as outlined in the Indian Pharmacopoeia. It describes 5 grades of powder sizes defined by the IP based on their ability to pass through various mesh sieves. Common separation techniques include sieving, cyclone separation, air separation, and elutriation. Sieving involves using a set of sieves arranged from largest to smallest mesh size to separate powder fractions. Cyclone and air separators use centrifugal forces to separate solids from gases. Elutriation separates powders based on particle density differences in a moving fluid.
objectives, applications, mechanism of size separation, the official standard of powders, sieves, sieve shaker, cyclone separator, air separator, bag filter, elutriation tank
The spray dryer uses a stream of hot gas to rapidly dry liquid materials into fine particles or powder. The liquid is atomized and sprayed into a drying chamber where it contacts the hot gas, drying the droplets. The dried particles are then collected in a cyclone separator. Spray drying is useful for heat-sensitive materials and allows for continuous, rapid drying to produce uniform, spherical particles. However, spray dryers are bulky, expensive to operate, and have low thermal efficiency.
The document discusses a hammer mill, which reduces particle size through repeated impacts using rotating hammers. It has various pharmaceutical uses including grinding raw materials and excipients. A hammer mill works by feeding materials into a chamber containing rapid rotating hammers that fracture particles through collisions. Properly sized particles pass through screens while larger ones require further grinding. Key advantages are rapid grinding and easy control of particle size. Disadvantages include potential heat damage and susceptibility to foreign objects in the feed.
Size reduction, or comminution, is the process of reducing substances into smaller pieces or fine powder. It increases the surface area, allowing for faster dissolution and extraction of active constituents. The degree of size reduction depends on factors like the drug's hardness, solvent used, and extraction process. Various size reduction methods include cutting, compression, impact, and attrition. Common mills are the cutter mill, roller mill, hammer mill, ball mill, and fluid energy mill. Levigation involves wet grinding while elutriation separates fine and coarse particles.
Size reduction is the process of decreasing the physical dimensions of objects or materials by breaking them into smaller pieces. It is done by applying external forces to break larger particles into smaller ones. The main objectives of size reduction are to increase surface area for reactions, separate materials, improve handling and mixing. Some common size reduction methods are impact, compression, shear and attrition. Key factors that affect size reduction are the material's hardness, structure, abrasiveness, softening temperature and moisture content. Several theories describe the energy required for size reduction, including Rittinger's, Bond's and Kick's theories. Only about 10% of the total energy input is actually used to reduce particle size.
This document discusses mixing and homogenization processes. It defines mixing as combining two or more substances together, and identifies perfect mixing as each particle of one material lying adjacent to a particle of the other material. The objectives of mixing are outlined. There are three types of mixtures discussed: positive, negative, and neutral. The mechanisms and equipment used for mixing powders, liquids, and semi-solids are described. Homogenization is defined as preparing a fine emulsion from a coarse one by converting large globules to small globules. Common homogenization equipment like hand homogenizers, Silverson mixers, and colloidal mills are summarized.
Mixing is a general term that includes stirring, beating, blending, binding, creaming, whipping, and folding. In mixing, two or more ingredients are evenly dispersed in one another until they become one product.
Size reduction is a process of reducing large solid unit masses, coarse particles or fine particles.
Size reduction may be achieved by two methods:
1] Precipitation
2] Mechanical process
1] Precipitation method: Substance is dissolve in appropriate solvent.
2] Mechanical process: Mechanical force is introduce by using different equipments like ball mill, colloid mill etc.
Size reduction is the process of reducing the particle size of a substance through mechanical means like grinding or milling. It has several objectives like increasing surface area, improving mixability and compressibility. Factors like hardness, toughness, abrasiveness affect size reduction. Common mechanisms are cutting, compression, impact and attrition. Equipment used include colloid mill, hammer mill, ball mill and jet mill which work on different principles to produce fine particles.
The document discusses various methods of size reduction or comminution. It describes different types of mills used for size reduction including hammer mill, ball mill, colloid mill, and fluid energy mill. The objectives of size reduction are to reduce particle size, increase surface area, improve handling and flow of powders. Factors affecting size reduction include hardness, toughness, moisture content and specific mills are described such as how a cutter mill uses cutting blades and a ball mill uses grinding balls to reduce particle size.
This document discusses size separation techniques used in the pharmaceutical industry. It begins by defining size separation as the process of separating particles into different sizes using screening surfaces. Some common objectives of size separation are to classify materials by size, control size variation, and enhance product performance. Sieves are the most common screening devices and come in various materials and constructions like woven wire, punched plates, and bolting cloth. Key size separation techniques discussed are agitation, brushing, and centrifugal motion, which use vibration, rotation, or air flow to move particles through sieves.
The document discusses size reduction techniques used in pharmaceutical engineering. It describes the hammer mill and ball mill, which use mechanical forces for size reduction. The hammer mill works by impact between rapidly moving hammers and powder materials, while the ball mill uses impact and attrition between rapidly moving balls inside a rotating cylinder. Both provide descriptions of their basic principles, constructions, operating parameters, advantages and disadvantages.
This document discusses various size reduction equipment, including hammer mills, ball mills, and disintegrators. It provides advantages and disadvantages of hammer mills, such as their ability to control particle size but potential for heat buildup. Ball mills are described as using impact between rapidly moving balls and material to reduce size. Key advantages are their ability to produce fine powder and handle wet or dry materials. Disintegrators work via impact of fast-spinning beaters inside a drum and are useful for reducing very hard drugs to a fine powder.
This document summarizes a presentation on wet granulation equipment. It describes the process of wet granulation which involves adding a liquid solution to powders to form granules. It then discusses various types of equipment used in wet granulation including rapid mixing granulators, fluidized bed dryers, vibratory sifters, multi mills, and double cone blenders. For each type of equipment, it provides details on its working principles, components, parameters to control, and advantages.
The document discusses three main modes of size reduction: cutting, compression, and impact. Cutting involves using sharp blades to cut fibrous and waxy materials, like in a cutter mill. Compression crushes soft materials between rollers through applied pressure, as in a roller mill. Impact involves high-speed hammers or bars splitting materials apart on impact, making it suitable for all drugs. Examples of impact mills are fluid energy mills and ball mills. Attrition breaks down brittle drugs through rubbing action between surfaces, as also seen in fluid energy and ball mills.
Size reduction, process of size reduction, size reduction a topic of pharmac...RajkumarKumawat11
Size reduction, process of size reduction, size reduction a topic of pharmaceutics, cutter mill, roller mill, hammer mill, ball mill, fluid energy mill, the disintegrator, mills used in pharmaceutical process
Size reduction is a vital unit operation in pharmaceutical manufacturing that involves reducing the size of solid materials to enhance their dissolution properties, improve bioavailability, and facilitate further processing. It is a fundamental step in drug formulation and is employed in various dosage forms like tablets, capsules, and powders.
Size reduction is the process of reducing large solid masses into smaller particles through mechanical means like impact, compression, cutting, or attrition. The objectives are to increase surface area, improve therapeutic effectiveness, produce uniform mixtures, and reduce sedimentation in suspensions. Common size reduction equipment used in pharmaceutical industries include hammer mills, ball mills, edge runner mills, end runner mills, and fluid energy mills which operate based on different mechanisms like impact, compression, cutting or attrition. Key factors affecting size reduction are material properties like hardness, moisture content, and melting point.
This document discusses size reduction, also known as milling, comminution, crushing, or grinding. It is the process of reducing materials to smaller pieces or powders through mechanical means. The objectives and factors affecting size reduction are described. The key mechanisms of size reduction are cutting, compression, impact, attrition, and a combination of impact and attrition. Several types of mills used for size reduction are also outlined, including their operation, uses, advantages, and disadvantages.
Size reduction is the process of reducing larger particles into smaller particles. There are various mechanisms for size reduction including cutting, compression, impact, attrition, and combinations of impact and attrition. Different types of mills use these mechanisms, such as hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills. The energy required for size reduction depends on factors like the material hardness, toughness, stickiness, softening temperature, and moisture content. Laws like Rittinger's law, Kick's law, and Bond's law can predict the energy requirements.
This document discusses size reduction, which is the process of reducing drugs into smaller pieces or fine powder. It defines size reduction and lists its purposes. Factors that affect size reduction include hardness, fiber content, elasticity, melting point, and hygroscopicity. Common size reduction methods are cutting, compression, impact, attrition, and shear. Equipment used for size reduction includes cutter mills, roller mills, hammer mills, and ball mills. Cutter mills use knives to cut materials while roller mills use compression between rollers. Hammer mills rely on impact from hammers and ball mills use impact and attrition from balls within a rotating cylinder.
This document discusses size reduction, which is the process of reducing drugs into smaller pieces or fine powder. It defines size reduction and lists its purposes. Factors that affect size reduction include hardness, fiber content, elasticity, melting point, and hygroscopicity. Common size reduction methods are cutting, compression, impact, attrition, and shear. Equipment used for size reduction includes cutter mills, roller mills, hammer mills, and ball mills. Cutter mills use knives to cut materials while roller mills use compression between rollers. Hammer mills rely on impact from hammers and ball mills use impact and attrition from balls within a rotating cylinder.
chapter: Unit operations process size reduction and size seperationmanjushacharde1
The document discusses various unit operations used in the pharmaceutical industry such as size reduction, size separation, mixing, filtration, and drying. It describes size reduction equipment like hammer mills and ball mills. It covers factors that affect size reduction like material hardness. It also explains size separation processes and equipment like sieves and cyclone separators. Standards for powder sizes according to the Indian Pharmacopoeia are provided.
Size reduction is an important process in pharmaceutical industries that reduces the size of raw materials through mechanical means such as impact, compression, cutting, and attrition. The objectives of size reduction include increasing surface area and therapeutic effectiveness, producing particles of a narrow size range to improve mixing and flow properties, and reducing sedimentation in suspensions. Common size reduction mills described in the document include hammer mills, ball mills, edge runner mills, end runner mills, and fluid energy mills, which vary in their mechanisms and suitability for different materials.
Size reduction is the process of reducing larger particles into smaller particles using external forces. The key mechanisms of size reduction are cutting, compression, impact, attrition, and a combination of impact and attrition. Different types of mills use these mechanisms, including hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills. The energy required for size reduction depends on factors like the material hardness, toughness, stickiness, and moisture content. Proper mill selection and operation are necessary to efficiently reduce particle sizes.
Hammer mills are machines that use hammers attached to a shaft to break materials into smaller pieces through impact. Materials enter the crushing chamber and are struck by hammers rotating at high speeds, typically 2000-6000 rpm. The material is crushed by hammer impact, collisions with chamber walls, and particle-to-particle impact. Crushed material passes through a screen that separates fine material from coarser pieces. Screen size, shaft speed, and hammer configuration determine the quality of the final product. Hammer mills are commonly used to grind foods, chemicals, and other materials in applications such as powder production, food processing, and enhancing ingredient activity.
The document discusses spheronizers and marumerizers which are used to shape extrudates into spherical granules. It describes the extrusion and spheronization process which involves dry mixing, wet massing, extrusion to form rod-shaped particles, and spheronization to round the rods into spheres. Key factors that influence spheronization include the disc speed, charge volume, disc groove geometry, diameter and retention time. Spheronizers have advantages like improved flow properties, uniform packing and coating of particles.
The document discusses various size reduction techniques used in pharmaceutical industries. Size reduction is done to increase surface area, improve dissolution and help in uniform mixing. It can be achieved through mechanisms like impact, compression, cutting and attrition. Milling equipment discussed include hammer mill, ball mill, edge runner mill and end runner mill. Hammer mill uses impact between hammers and material. Ball mill works on impact and attrition of balls and material. Edge runner mill utilizes crushing between heavy rollers. End runner mill employs crushing by a heavy pestle. Fluid energy mill operates on impact and attrition of particles in a high speed air stream. Proper mill selection depends on material properties and desired particle size.
Size reduction is the process of reducing the particle size of a substance through mechanical means such as cutting, grinding, and milling. This increases the surface area and can improve properties like dissolution rate and bioavailability. In pharmaceutical applications, size reduction allows for more uniform mixing, improved formulations, and sustained drug release. It is carried out manually or using various mills that employ mechanisms like cutting, compression, impact, and attrition. Proper size reduction is important for optimizing drug delivery and bioavailability.
The document discusses various methods of size reduction used in pharmaceutical processing. It describes the objectives, principles, construction and working of common size reduction equipment such as hammer mills, ball mills, fluid energy mills, edge runner mills, and end runner mills. Size reduction is achieved through mechanisms like cutting, compression, impact and attrition. Factors like speed, material properties, and construction of the equipment affect the efficiency of size reduction. The summary provides an overview of the key information covered in the document.
The ball miller machine is a tumbling mill that uses steel milling balls as the grinding media, applied in either primary grinding or secondary grinding applications.
Size reduction involves breaking larger particles into smaller particles through processes like cutting, impact, attrition, and compression. This increases surface area and can improve properties like dissolution, absorption, extraction, and stability of materials. However, it also carries risks like heat generation leading to degradation.
Ball mills reduce particle size using impact and attrition from balls. They consist of a rotating cylinder filled partially with balls. At an optimal speed, centrifugal force causes balls to cascade, breaking particles through collision and friction. Hammer mills similarly use impact, but from rapidly moving hammers striking materials confined within a chamber. Both are common pharmaceutical size reduction equipment.
Size reduction is a process of reducing large solid unit masses - vegetables or chemical substances into small unit masses, coarse particles or fine particles.
Lipid metabolism is the synthesis and degradation of lipids in cells.
It involves the breakdown or storage of fats for energy and the synthesis of structural and functional lipids, such as those involved in the construction of cell membranes.
In animals, these fats are obtained from food or synthesized by the liver.
1. Glycolysis is the breakdown of glucose to pyruvate with production of ATP. Glycolysis occurs in the cytoplasm and is the first step of carbohydrate metabolism.
2. The citric acid cycle (Krebs cycle) occurs in the mitochondria and involves the oxidation of acetyl CoA derived from pyruvate to carbon dioxide. This produces NADH and FADH2 to be used in the electron transport chain for ATP production.
3. Glycogenesis is the formation of glycogen from glucose-6-phosphate in the liver and muscle cells for energy storage. Glycogenolysis breaks down glycogen back to glucose-6-phosphate to regulate blood glucose levels.
Vitamins are organic compounds that are essential for normal growth and nutrition and are required in small quantities, their deficiency causes diseases.
Biochemist Casimir Funk discovered vitamin B1 in 1912 in rice bran.
It cannot be synthesized in sufficient quantities by an organism and must be obtained from the diet.
Catalysts are something that speeds up the chemical reaction. Almost all biochemical reactions require catalysts.
Enzymes are biocatalysts. Biochemical catalysts speed up the biochemical reactions.
In presence of an enzyme, less energy is required for the reaction to take place.
A catalyst may be defined as a substance that increases the velocity or rate of chemical reactions without itself undergoing any change in the overall process.
Nuclei acid is a naturally occurring chemical compound containing phosphoric acid, sugars, and a mixture of organic bases (purines and pyrimidines).
The two main classes of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
DNA is the master blueprint for life and constitutes the genetic material in all free-living organisms and most viruses. DNA is the chemical basis of heredity and may be regarded as the reserve bank of genetic formation. DNA is exclusively responsible for maintaining the identity of different species of organisms over millions of years.
RNA is the genetic material of certain viruses, but it is also found in all living cells. The genes control protein synthesis through the mediation of RNA.
“These are the naturally Organic compounds, insoluble in water, soluble in organic solvents (alcohol, ether, etc.), which are potentially related to fatty acids & utilized by living cells."
Lipids are a heterogeneous group of compounds.
They are esters of fatty acids. Lipids occur widely in plants and animals. Lipids include fats, oils, waxes, and related compounds.
Lipids are a family of organic compounds, composed of fats and oils. These molecules yield high energy and are responsible for different functions within the human body.
Proteins are naturally occurring polymers made up of amino acids and linked together by peptide bonds.
Proteins are the most abundant organic molecules in the living system.
The term "protein" is derived from the Greek word proteios, meaning holding the first place.
These are nitrogenous organic compounds that have large molecules weight of one or more long chains of amino acids.
Proteins are made from 20 ɑ-amino acids. (chains of amino acids)
A single unit of amino acid is known as a monomer. When many monomers combine together, they form polymers.
Carbohydrates are polyhydroxy aldehydes, ketones, or compounds derived from their hydrolysis.
Carbohydrates are also known as sugars.
Carbohydrates have the general formula C(H2O)n, where n is the number of carbon atoms.
Carbohydrates are mainly composed of carbon, hydrogen, and oxygen.
The term “sugar” is applied to carbohydrates that are soluble in water and sweet to taste.
The term "biochemistry" originated from combining the words "bios," meaning life, and "chemistry."
Biochemistry is defined as the branch of science that deals with the study of chemical reactions that take place inside a living organism.
The word "biochemistry" was first introduced by a German chemist, Carl Neuberg, in 1903.
Introduction to Clinical Pharmacy Practice.pptxSHIVANEE VYAS
Clinical pharmacy is a branch of hospital pharmacy that deals with various aspects of patient care, including the dispensing of drugs and advising the patient on the safe and rational use of those drugs.
It is an electronic device that stores, retrieves, and processes data, and can be programmed with instructions. It can also perform several complex and complicated functions.
A computer is composed of hardware and software and can exist in a variety of sizes and configurations.
Solid unit dosage forms the drug is enclosed within the water-soluble shell or an envelope either a hard or soft shell. Shell is typically made of gelatin primarily intended for oral delivery and provides a rapid release of contents.
Generally, the shells are formed from gelatin.
COPD (chronic obstructive pulmonary disease) is a group of lung diseases that make it hard to breathe and get worse over time.
Normally, the airways and air sacs in the lungs are elastic or stretchy.
When we breathe in, the airways bring air to the air sacs.
The air sacs fill up with air, like a small balloons.
When we breathe out, the air sacs deflate, and the air goes out.
In COPD, less air flows in and out of airways because of one or more problems:
-The airways and air sacs in the lungs become less elastic
-The walls between many of the air sacs are destroyed
-The walls of the airways become inflamed
-The airways make more mucus than usual and can become clogged
Asthma is a chronic disease involving the airways in the lungs.
Asthma is a condition in which your airways narrow and swell and may produce extra mucus.
This can make breathing difficult and trigger coughing, a whistling sound (wheezing) when you breathe out, and shortness of breath.
Blood pressure is the force of the blood pushing against the walls of the arteries.
Each time our heart beats pumps blood into the arteries.
Blood pressure is highest when the heart beats, pumping the blood. This is called systolic pressure.
When our heart is at rest, between beats, our blood pressure falls. This is called diastolic pressure.
A blood pressure reading uses these two numbers. Usually, the systolic number comes before or above the diastolic number.
Congestive heart failure is a chronic progressive condition in which the heart cannot pump enough blood to meet the metabolic need of the body because of pathological changes in the myocardium.
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Angina may feel like pressure or squeezing in your chest. The pain also can occur in your shoulders, arms, neck, jaw, or back. Angina pain may even feel like indigestion.
Angina is chest pain or discomfort that occurs if an area of your heart muscle doesn't get enough oxygen rich blood.
Introduction to Pharmacotherapeutics.pptxSHIVANEE VYAS
This document discusses pharmacotherapeutics, which is the study of the therapeutic use and effects of drugs. It covers key topics like drug absorption, distribution, elimination, and action/effects. Pharmacotherapeutics also examines how drugs are used to treat diseases based on their receptor binding capabilities and bioavailability. The document outlines the objectives of pharmacotherapeutics like maximizing drug effects and minimizing side effects. It also discusses rational drug use, evidence-based medicine, essential medicines lists, and standard treatment guidelines.
Prescription | Parts of Prescription | Handling of PrescriptionSHIVANEE VYAS
A prescription is an order written by a physician, dentist, or veterinarian to a pharmacist to compound and dispense a specific medication for the patient.
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
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Executive Directors Chat Leveraging AI for Diversity, Equity, and InclusionTechSoup
Let’s explore the intersection of technology and equity in the final session of our DEI series. Discover how AI tools, like ChatGPT, can be used to support and enhance your nonprofit's DEI initiatives. Participants will gain insights into practical AI applications and get tips for leveraging technology to advance their DEI goals.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Physiology and chemistry of skin and pigmentation, hairs, scalp, lips and nail, Cleansing cream, Lotions, Face powders, Face packs, Lipsticks, Bath products, soaps and baby product,
Preparation and standardization of the following : Tonic, Bleaches, Dentifrices and Mouth washes & Tooth Pastes, Cosmetics for Nails.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
2. Content
• Size reduction –Introduction
• Objectives and factors affecting size reduction
• Methods of size reduction
• Equipment's used for Size reduction
3. Introduction
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.
4. • Objectives of Understanding Size Reduction
1. Size reduction leads to increase of surface area.
2. To increase the therapeutic effectiveness of certain drugs by reducing the particle size.
3. To get the uniform powder because particle size reduction helps the uniform mixing of
drugs for the preparation of dosage forms.
4. To increase the rate of absorption of a drug. The smaller the particle size, the greater the
rate of absorption.
5. Pharmaceutical suspensions require finer particle size. It reduces rate of sedimentation.
6. The stability of emulsions is increased by decreasing the size of the oil globules.
7. All the ophthalmic preparations and preparations meant for external application to the
skin must be free from gritty particles to avoid irritation of the area to which they are
applied.
8. The physical appearance of ointments, pastes and creams can be improved by reducing its
particle size
5. Factors affecting size reduction
1 Hardness: The hardness of the material affects the process of size reduction .It is easier to
break soft material to a small size than hard material.
2 Toughness: The crude drugs of fibrous nature or those having higher moisture content ,are
generally tough in nature. A soft but tough material may present more problem in size
reduction , than a hard but brittle substance.
3 Stickiness: Stickiness causes a lot of difficulty in size reduction. This is due to the fact
that material adheres to the grinding surfaces or sieve surface of the mill. It is difficult to
power a drugs of having gummy or resinous nature, if the method used for size reduction
generates heat. Complete dryness of material may help to overcome this difficulty.
4 Material structure: Materials which show some special structure may cause problem
during size reduction e.g. vegetable drugs which have cellular structure, generally produce
long fibrous particles on its size reduction. Similarly a mineral substances having lines of
weakness, produces flake like particles on its size reduction.
6. 5. Moisture content: The presence of moisture in the material influences a number of its properties
such as hardness, toughness or stickiness which in its turn affects the particle size reduction. The
material should be either dry or wet. It should not be damp. The material having 5% moisture in
case of dry grinding and 50% moisture in wet grinding does not create any problem.
6. Softening temperature: Waxy substances such as stearic acid or drugs containing oils or fats
,become softened during the size reduction processes if heat is generated. This can be avoided by
cooling the mill.
7. Purity required: Various mills used for size reduction often cause the grinding surfaces to wear
off and thus impurities come in the powder .If a high degree of purity is required, such mills must
be avoided. Moreover, the mills should be thoroughly cleansed between batches of different
material in order to maintain purity.
8. Physiological effect: Some drugs are very potent. During their particle size reduction in a mill
dust is produced which may have an effect on the operator .In such cases, the enclosed mills may
be used to avoid dust.
9. Ratio of feed size to product size: To get a fine powder in a mill, it is required that a fairly small
feed size should be used. Hence it is necessary to carry out the size reduction process in several
stages, using different equipment e.g. preliminary crushing followed by coarse powder and then
fine grinding.
10. Bulk density: The output of the size reduction of material in a machine, depends upon the bulk
density of the substance.
7. Methods of size reduction
The following are the methods of size reduction, in which
different mechanism are involved;
1. CUTTING: The material is cut on a small scale by
means of sharp blade, knives etc. On a large scale, a
cutter mill is used.
CUTTER MILL
• Principle: The size reduction is done by cutting with the
help of sharp knives.
• Construction: there are two types of knives which are
fitted in this mill. These are stationary knives and rotating
knives. The stationary knives are fixed in the casting
whereas the rotating knives are attached to the rotor. The
upper part of casting also contains hopper inlet, whereas
the lower part has a screen of desire aperture size.
8. • Working: the material to be cut into the hopper of the mill.
The rotor rotates at a high speed. Due to the rotation of the
rotor, the material comes very close between stationary
knives and rotating knives. It cut down the material into
small pieces. Screen retains the material in the mill, until
the desire degree of size reduction has been affected. The
product is collected which comes out of the sieves.
• Uses: This mill is used for the size reduction of soft
materials such as roots, peels or wood.
9. 2. COMPRESSION: In this method, the material is crushed by the
application of pressure. Example is Roller Mill.
ROLLER MILL
• Principle: The material is crushed by the application of pressure. The
mill works on the principle of compression of material by applying a
pressure on it.
• Construction: It consists of two cylindrical rollers made of stone or
metal, which are mounted horizontally. These rollers are capable of
rotation on their longitudinal axis. These rollers may be from a few
centimeters up to a meter in diameter. Generally, one of the roller is
driven directly, while the second one runs freely. The gap between the
rollers can be controlled to obtain the desired particle size.
• Working: The rollers are allowed to rotate. The material is fed from
the hopper into the gap between the two rollers. The material is
crushed while passing through the rollers can be adjusted to control
the degree of size reduction. The product is collected into a receiver.
• Uses: The roller mill is used for crushing and cracking of seeds before
extraction of fixed oil. It is also used to crush the soft tissues, to help
in the penetration of solvent during the extraction process.
10. 3. IMPACT: This involves the operation of hammers at high speed.
When a lump of material strikes the rotating hammers, the
material splits apart. This action continue until particle of desired
size are obtained. Example is hammer mill.
HAMMER MILL
• Principle: The hammer mill operate on the principle of impact
between rapidly moving hammers mounted on a rotor and the
powder material.
• Construction: The hammer can be either horizontal or vertical
shaft type. Hammers are usually made of hardened steel,
stainless steel with impact surface. This unit is enclosed with a
chamber containing a removable screen through which the
material must pass. Screen are prepared using metal sheet of
varying thickness with perforated holes.
11. Working: The hammers are allowed to be in continuous motion (8000-15000RPM)
the feed material is placed into the hopper, which flows vertically down and then
horizontally, while hammers are in continuous motion. These rotating hammers
beat the material to yield smaller particle. Then, these pass through the screen.
Due to the high speed of operation, heat is generated which may affect thermolabile
drugs or materials. Moreover, high speed of operation also causes damage to the
mill if foreign objects such as stone or metal is present in the feed.
Uses The hammer mill is used for producing intermediate grades of powder from
almost all types of substances except sticky materials that choke the screen. The
expected particle size may vary from 10 to 400mm
12. THE DISINTEGRATOR
• Principle: The size reduction in disintegrator is done by
impact.
• Construction: It consists of a steel drum having a shaft in the
center. The shaft contains a disc, on which four beaters are
fixed. The shaft rotates with a speed of 5000-7000 RPM. The
side and upper inner surface of the drum is rough. The lower
part of the drum has a detachable screen or sieve. The sieve
has a definite pore size.
• Working: The beaters are mainly responsible for grinding but
are helped by the undulation of the inner surface and
roughness of drum.
• The material is fed to beaters, through hopper which is fitted
to the drum. The material is broken into small particles by
impact of the beaters. Due to high velocity of beaters the air
velocity inside the chamber is increased. The air is allowed to
pass through an outlet on which the dust bag is tied, which
retains the fine particles of powder.
• Uses: The mill is used to powder all types of drugs including
very hard drugs. The drug should be dried before feeding into
the disintegrator to get a fine powder. To avoid the jamming
of the beaters of the disintegrator, use moderately small
pieces.
13. 4. ATTRITION: This process involves breaking down of the material
by rubbing between two surfaces, Example is ball mill.
BALL MILL
These are also known as tumbling mills.
• Principle: It works on the principle of impact and attrition both for
the size reduction.
• Construction: It consists of a hollow cylinder which is mounted on a
metallic frame in such a way, that it can be rotated on its
longitudinal axis. The length of the cylinder is slightly greater than
its diameter.
The cylinder and balls are made of metal and are usually lined with
chrome. In the pharmaceutical industry, sometimes the cylinder of the
ball mill is lined with rubber or porcelain. The balls used in these
mills are also made of rubber or porcelain.
14. • Working: The drug to be ground is put into the cylinder of the
mill in such a quantity that it is filled to about 60% of the
volume. A fixed number of balls are introduced and the cylinder
is closed. The mill is allowed to rotate on its longitudinal axis.
The speed of rotation is very important. At a low speed, the mass of
balls will slide or roll over each other and only a negligible amount
of size reduction will occur.
At a high speed, the balls will be thrown out to the walls by
centrifugal force and no grinding will occur.
But at correct speed, the centrifugal force just occurs with the
result that the balls are carried almost to the top of the mill and
then fall in. By this way the maximum size reduction is effected by
the impact of particles between the balls and by attrition between
the balls.
After a suitable time, the material is taken out and passed through
a sieve to get powder of the required size.
• Uses: The mill is used to grind brittle drugs to fine powder.
High speed
Low speed
Correct speed
15. • Advantages:
1. It can produce very fine particles.
2. It can be used for continuous operation.
3. Ball mill is suitable for both wet and dry grinding process.
4. Toxic substance can be ground, as the cylinder is a closed system.
5. Since the mill is closed system, sterility can be achieved.
6. In the ball mill, installation, operation and labor costs are low.
7. It is capable of grinding a large variety of materials of different character and
of different degree of hardness.
• Disadvantages:
1. The ball mill is a very noisy machine.
2. Soft, sticky, fibrous material cannot be milled by ball mill.
16. Fluid Energy Mill
• Principle: fluid energy mill works on the principle of impact and attrition.
• Construction: It consist of a loop of pipe, which has a height about 2 meter and diameter
may be ranging from 20-200 millimeter. The mill surface may be made of stainless steel.
There is an inlet for the feed and a series of nozzles for the inlet of air or inert gas. An
outlet with a classifier (cyclone separator or bag filter) is fitted to allow the escape of air.
17. • Working: The air or inert gas is introduced with a very high pressure through the
nozzles. Solids are introduced into air stream through inlet. Due to high degree of
turbulence, impact and attrition forces occurs between the particles the fine particles
are collected through a classifier. Fluid energy mill reduces the particles to 1-20 micron.
The powder remains in the mill, until its size is reduced sufficiently.
• Uses: fluid energy mill is used to reduce the particle size of most of the drugs such as
antibiotics and vitamins. Ultra fine grinding can be achieved.
• Advantages:
1. It has no moving parts, hence heat is not produced so it is useful for heat sensitive
substance such as vitamins, antibiotics and sulphonamides.
2. The particle size of powder can be controlled due to the use of a classifier.
3. It is rapid and an efficient method for reducing powder to 30mm or less.
• Disadvantages:
1. It is not suitable for milling of soft, sticky and fibrous material.
2. The equipment is expensive.