Dairy Engineering

1.  Dairy Engineering                                                                                                                          3 (2 + 1)

Sanitization : Materials and sanitary features of the dairy equipment. Sanitary pipes and fittings, standard glass piping, plastic tubing, fittings and gaskets, installation, care and maintenance of pipes & fittings. Description, working and maintenance of can washers, bottle washers. Factors affecting washing operations, power requirements of can the bottle washers, CIP cleaning and designing of system. Mechanical Separation : fundamentals involved in separation. Sedimentation, principles involved in filtration, Types, rates of filtration, pressure drop calculations. Gravity setting, principles of centrifugal separation, different types of centrifuges. Application in Dairy Industry, clarifiers, tri processors, cream separator, self dislodging centrifuge, Bacto-fuge, care and maintenance of separators and clarifiers. Homogenization : Classification, single stage and two stage homogenizer pumps, power requirement, care and maintenance of homogenizers, aseptic homogenizers. Pasteurization : Batch, flash and continuous (HTST) pasteurizers, Flow diversion valve, Pasteurizer control care and maintenance of pasteurizers. Different type of sterilizers, in bottle sterilizers, autoclaves, continuous sterilization plant, UHT sterilization , Aseptic packaging and equipment. Care and maintenance of Sterilizers. Filling Operation : Principles and working of different types of bottle filters and capping machine, Pouch filling machine (Pre-pack and aseptic filling bulk handling system, care and maintenance. Mixing and agitation : Theory and purpose of mixing. Equipments used for mixing solids, liquids and gases. Different types of stirrers, paddles and agitators. Power consumption of mixer-impeller, selection of mixing equipment in dairy industry, mixing pumps.

Practical :   To study : S.S. pipes and fitting, gasket materials  and S.S. milk pumps : Milk tanker and milk storage tanks : can washer and bottles washers : C.I.P. Cleaning equipments: Homogenizers: Batch and continuous Pasteurizers : Different Controls on Pasteurizer : Different sterilizers :  Pouch filling machine : Different types of agitators : Bottle filling and  Capping machine :  Determination of the rate of filtration and settling : Visit to a dairy plant.


2. Dairy Process Engineering :                                                                                                                                                                     3 (2 + 1)

Evaporation : Basic principles of evaporators, construction and operation, Different types of evaporators used in dairy industry, Calculation of heat transfer area and water requirement of condensers, Basic concepts of multiple effect evaporators, Operations and various feeding systems, Economy of operation, thermo processor and MVR system, Care and maintenance of evaporators. Drying : Introduction to principle of drying, equilibrium moisture constant bound and unbound moisture, Rate of drying – constant and falling rate, effect of Shrinkage, Classification of dryers-spray and drum dryers, spray drying, etc., air heating systems, Atomization and feeding systems. Factors affecting bulk density of power, spray dryer controls, Theory of solid gas separation, cyclone separators, Bag Filters, Care and Maintenance of drum and spray dryers. Fluidization : Mechanisms of fluidization characteristics of gas-fluidization systems, Minimum Porosity, Bed Weight, Pressure drop in fluidized bed, Application of fluidization of drying, Batch fluidization, fluidized bed dryers.

Mechanization and equipment used in manufacture of indigenous dairy products, Butter and Ghee making machine, Ice-cream and Cheese making equipments. Packaging machines for milk & milk products.

Membrane Processing : Ultra filtration, reverse Osmosis and electro dialysis. Materials for membrane construction. Ultra filtration of milk, effect of milk constituents on operation, membranes for electro-dialysis.

 Practical : Study of construction and operation of : Vacuum pan : Double effect evaporator : Spray dryer : Vacuum and atmospheric drum dryers. Study and operation of Butter, ghee, Ic-cream and Cheese making equipments, study the Reverse Osmosis and Ultra filtration system : Design problems on Double effect evaporator and Vaccum Pan. Visit to a milk product plant.


3. Dairy Plant Design and Layout :                                                                                                                                                            3 (2 + 1)

Introduction of Dairy Plant design and layout. Type of dairies, perishable nature of milk, reception flexibility. Classification of dairy plants, Location of plant, location problems, selection of site. Dairy building planning, Process schedule, basis of dairy layout, importance of planning, principles of dairy layout. Space requirements for dairy plants, estimation of service requirements including peak load consideration. General points of considerations for designing dairy plant, floor plant types of layouts,  service accommodation, single or multilevel design. Arrangement of different sections in dairy, sitting the process sections, utility/service sections, offices and workshop. Arrangement of equipment, milk piping, materials handling in dairies, Common problems, office layouts-flexibility. Development         and presentation of layout, model planning, use of planning table in developing plot plant and detailed layout. Choice of building construction materials, floors, general requirement of dairy floor finishes, floors for different section of dairy foundations, walls doors and windows, Drains and drain layout for small and large dairies. Ventilation, fly control, mold prevention, illumination in dairy plants.

Practical : Building symbols and convention layouts for small, medium and large size dairies. Isometric presentation of piping. Design and layout of milk collection/chilling centre;  Fluid milk plant (small, medium and large); Single product dairy (i) Cheese (ii) Ice-cream (iii) Butter and (Iv) Ghee. Compsite dairy plant.

4. Instrumentation and Process Control                                                                                                                                     3 (2 + 1)

Absolute and secondary instruments, Types of secondary instruments, Essentials of indicating instruments, Constructional details of indicating instruments. Principle of induction type instruments- shaded pole method and two pole methods, compensation for frequency and temperature errors. Induction  type voltmeter, Ammeter, advantage and disadvantages, induction type single phase watt hour meter, their errors and remedies, Numerical, wattmeter, power fractometer, etc Characteristics of Instruments and Measuring Systems: Elements of generalized measuring system, static calibration, accuracy, sensitivity, reproducibility, static errors,  dead zone, drift in measuring instruments. Analog and digital representation of singles, Factors influencing the choice of transducers. Mechanical input Transducers: Level, Pressure, Flow, Velocity and Humidity-Resistive, Capacitive and Inductive, Dielectric system for humidity measurements. Temperature Transducers : Resistive, inductive, capacitive and thermoelectric transducer. Magnetic Transducers: Systems based on induction and magnetic effects on moving charges, Transducers based on permeability variation.


Practical : Preparation and calibration of thermocouple; study the construction and working of Bourden  pressure gauge. Study the mechanism of pH meter and its electrodes. Study a pressure transducer. Study a proximity sensor. Study of the different parts and working of  Rotameter. Study the different parts and working of pressure switch. Study the different parts of an indicating instrument. Study the different parts and their working of single phase induction type watt hour meter. Visit to a microprocessor controlled dairy plant.


5. Engineering Drawing :                                                                                                                                                                    2 (0 + 2)

Drawing of lines, lettering and dimensioning types of lines, types, types of lettering types of dimensioning . Drawing of scales. Plain scale, diagonal scale, comparative scale, and Vernier scale. Drawing of projections; Orthographic projections, methods of projections. Drawing of screw threads; Types of threads and terminologies used in lit. Screw fastening: Types of nuts, types of bolts, stud, locking arrangements for nuts and Foundation bolt. Drawing of rivets and riveted joints forms of vivet heads, types of riveted; joints, failure of riveted joints. Drawing of welded joints: Forms of welds, location and dimensions of welds. Drawing of keys, cotter joint, pin joints types of keys, types of cotter joints, pin joints. Drawing of shaft couplings; Rigid couplings, loose couplings, flexible couplings universal coupling. Drawing of shaft bearings. Journal bearings, pivot bearings, collar bearings.


6. Principles of Dairy Machine Design                                                                                                                                               3 (2 + 1)

Basic concepts in Statics and Dynamics. Force Systems. Equilibrium condition, Friction, Law of friction, Second moments of inertia, Parallel axis theorem. Dynamics : Equation of motion. Translation and rotation of  a Rigid body, work and mechanics of materials : Stress-Axial Load Classification Strain-Hooke’s law, stress-strain diagram, Poisson’s Ratio :  Shearing Stresses. Torsion, Torsion formula, Angle to Twist of circular members. Power transmission shear force and bending moments, Shear in Beams, Bending Moment in beams. Pure bending of beams, Flexural stress shearing stresses in beams relations between centre, Torsional and flexural loads. Machine Design : Procedures, Specification Strength, design factor, factor of safety selection of factor of safety. Materials and properties. Static strength  ductility, hardness, fatigue, designing for fatigue conditions. Theories of failure, Stresses in elementary machine parts, Design of a drive system. Design of length and thickness of belt. Bearing : Journal and Anti-friction bearings. Selection of ball, tapered roller and thrust bearing.  Springs, helical and leaf springs. Energy stored in springs. Design and selection of springs.

 Practical : Engineering Statics & Dynamics. Work and Energy. Linear and angular Momentum. Stress-strain diagram evaluation of elastic constants. Power transmission. Shear force and bending moment diagrams. Flexural stresses. Shearing stresses in Beans. Fits and tolerances. Design stresses in elementary machine parts. Design of shafts, axles keys Springs, Couplings, Bearing.


7.  Workshop Practice :                                                                                                                                                                               2 (1 + 1)

Introduction to workshop practice, safety, care and precautions in workshop. Wood working tools and their use, carpentry and pattern making. Mould material and their applications. Heat treatment processes : hardening tempering, annealing, normalizing etc.
Metal cutting Soldering & Brazing, Electric are welding, Gas welding. Smithy and forging operations, tools and equipment. The bench : Flat surface filing, Chipping, Scraping Marking out, Drilling and Screwing. Use of jigs and fixtures in production. Introduction to following machine tools : (a) Lathe (b) Milling machine (c) Shaper and planner (d) Drilling and boring machines (e) Grinder (f) CNC machines.


Practical : Simple exercises in Filing and Fitting, Chipping and Hack Sawing, Chiseling, Tapping and smithy practice. Simple exercises in Are, Gas, & Argon welding. Simple exercises in Soldering, Brazing, Basic joints in carpentry.


8.  Fluid Mechanics :                                                                                                                                                                                 3 (2 + 1)

Units and dimensions, Properties of fluids. Static pressure of liquids : Hydraulic pressure, absolute and gauge pressure, pressure had of a liquid. Pressure on vertical rectangular surfaces. Compressible and non compressible fluids. Surface tension, capillarity. Pressure measuring devices, simple, differential, micro, inclined manometer, mechanical guges, Piezometer. Floating bodies : Archimedes Principle, stability of floating bodies. Equilibrium of floating bodies. Metacentric height. Fluid flow : Classification, steady uniform and non uniform flow, Laminar and turbulent, continuity equation, Bernolli’s theorem and its applications. Flow through pipes : Loss of head, determination of pipe diameter. Determination of discharge, friction factor, critical velocity. Flow through orifices, mouthpieces, notches and weirs, Vena contracta, hydraulic coefficients, discharge losses, Time for emptying a tank. Loss of head due to contraction, enlargement at entrance and exit of pipe. External and internal mouthpieces, types of notches, rectangular and triangular notches, rectangular weirs Venturimeters, pitot tube, Rota meter. Water level point gauge hook gauge. Dimensional analysis : Buckingham’s theorem application to fluid flow phenomena. Froude Number, Reynolds number, Weber number and hydraulic similitude. Pumps: Classification, reciprocating, centrifugal pump. Pressure variation, work efficiency. Types of chambers, selection and sizing.


Practical :  Study of different tools and fittings, plotting flow rate versus pressure drop with U-tube manometer. Verification of Bernoulli’s theorem. Determination of discharge coefficient for venture, Orifice, V-Notch. Verification of emptying time formula for a tank. Determination of critical Reynold’s number by Reynold’ apparatus. Study of reciprocating, Centrifugal  and gear pump. Calibration of Rota meter. Study of different types of valves. Problems on following topics: Pressure, Capillarity and surface tension. Floating bodies, Liquid flow, venturimeter, orifice, Weir, flow through pipes, pumps.


9.  Heat & Mass Transfer                                                                                                                                                                            3 (2 + 1)

Basic heat transfer process, thermal conductivity, convective film co-efficient, Stefan Boltzman’s constant and equivalent radiation co-efficient, Overall heat transfer co-efficient, physical properties related to head transfer. Working principles and application of various instruments for measuring temperature. One-dimensional steady state conduction :theory of heat conduction, Fourier’s law, Derivation of Fourier’s equation in Cartesian co-ordinates, Linear heat flow through slab, cylinder and sphere. Heat flow through slab, cylinder and sphere with non-uniform thermal conductivity. Concept of electrical analogy and its application for thermal circuits, heat transfer through composite walls and insulated pipelines. One dimensional steady state head conduction with heat generation : Heat flow through slab, hollow sphere and cylinder with uniform heat generation, Development of equations of temperature distribution with different boundary conditions. Steady-State heat condition with heat dissipation to environment : Introduction to extended surfaces (FINS) of uniform area of cross-section. Equation of temperature distribution with different boundary conditions. Effectiveness and efficiency of the FINS. Introduction to unsteady state heat conduction. Convection : Forced and free convection, use of dimensional analysis for correlating variables affecting convection heat transfer, Concept of Nusselt number. Prandtl number, Reynolds number, Grashoff number, some important empirical relations used for determination of heat transfer coefficient. Heat Exchangers : General discussion, fouling factors, jacketed kettles, LMTD, parallel and counter flow heat exchangers, Shell and tube and plate heat exchangers, Heat exchanger design. Application of different types of heat exchangers in dairy and food industry. Fick’s Law of diffusion, steady state diffusion of gases and liquids through solids. Equimolal diffusion. Mass transfer co-efficient and problems on mass transfer.

 Practical : Determination of thermal conductivity : milk, solid dairy & food products. Determination of overall heat transfer co-efficient of : Shell and tube, plate heat exchangers and jacketed kettle used in Dairy & Food Industry. Studies on heat transfer through extended surfaces. Studies on temperature distribution and heat transfer in HTST pasteuriser. Design problems on heat exchangers. Study of various types of heat exchangers. Design problems on Mass Transfer.

 10.  Thermodynamics                                                                                                                                                                                  3 (2 + 1)

Basic concepts : systems, processes, cycles, energy, The Zeroth Law of Thermodynamics. Ieal gases : Equation of state, Compression and expansion of gases. The first Law of Thermodynamics : internal energy, enthalpy. The second Law of Thermodynamics: Thermodynamic temperature scale. Carnot cycle, entropy, reversibility, availability. Air Cycles : Otto, Diesel, dual efficiencies, plotting the cycles on various thermodynamic planes viz., p-V, T-S, p-h diagrm; etc. IC. Egines : Two strock and four strock cycles, construction, injection and ignition of fuel, performance of IC. Engines. Fuels : Chemical properties, air for combustion, Calorific value and its determination, Burners, firing of fuels. Renewable energy  sources. Properties of steam: Wet, dry saturated, superheated steam, Use of stem tables and Molier charts. Steam generators : Fire tube boilers, Water tube boilers. Boiler mountings and Boiler accessories. DBihar Agricultural Unversity ght : Natural, forced, fan, jet, Measurement of Height of chimney. Condensers. Layout of pipe-line and expansion joints. Boiler trial : Codes, Indian Boiler regulation acts. Air Compressors : Reciprocating, Single and two stage air compressors.

Practical : Application of thermodynamics in engineering problems. Study of 2-strock engine and 4-strokes engines. Performance tests on I.C. engines. Determination of dryness fraction of steam. To study the boiler installed in Model Plant, water softening Plant, Lancashire boiler, Locomotive boiler, Babcok & Wilcox boiler, Electrode boiler, Boiler mounting and steam-line labout and steam traps. Visit to sugar mill/rice mill or plant with steam urilization. Study of solar water heater and biogas plants and appliances.

11.  Refrigeration & Air Conditioning                                                                                                                                                          3 (2 + 1)

Basic refrigeration cycles and concepts : Standard rating refrigeration machines, Elementary vapour compression refrigeration cycle with reciprocating, rotary and centrifugal compressors. Theoretical vapour compression cycle, Departure from theoretical vapour compression cycle, representation on T-and p-h diagrams, Mathematical analysis of vapour  compression refrigeration system. Refrigerants : Primary and secondary refrigerants, common refrigerants (Ammonia, Froen), Brine, their properties and comparison. Multiple evaporator and compressor systems: Applications, One compressor systems: dual compression, Comparison of system, Control of multiple evaporator system, working and mathematical analysis of above systems. Refrigeration equipments: Compressor, Condenser, evaporator, Cooling tower, spray pond,, Basic elements of design, Construction, operation and maintenance, balancing of different components of the system. Refrigeration Controls : Low side and high side float valves, capillary tube, thermostatic expansion valve, automatic expansion valve, solenoid valve, High pressure and low pressure cutouts, thermostat, overload protector, common defects and remedies. Refrigeration Piping: Purpose, materials joint and fittings, water and brine pipe size selection. Absorption Refrigeration Systems:  Simple vapour absorption refrigeration systems, Practical absorption system, Refrigerant absorbent  combinations Absorption cycle analysis. Psychrometry : definition, properties of air-vapour mixtures psychrometric charts, Processes involving air vapour mixtures, Dehumidification, humidifiers, Humidity measurements, humidity control. Wet bulb, dry bulb temperature dew point temperature. Cooling load calculations; types of loads, design conditions for air cooling, air conditioning loads. Cold storage: Types of cold storage, types of loads in cold storage, Construction of cold storage. Insulating materials and vapour barriers.


Practical : Study of tools used in installation of a refrigeration plant including charging and detection of leaks. To study different parts and learn operation of bulk milk cooler. Study of different parts and learn the operation of a refrigeration plant/ice plant using ammonia refrigerant. Study of different parts and learn the operation of a vapour absorption refrigeration plant. Dismantling and assemble an open compressor and a sealed unit. Study different parts and refrigeration controls of the following (a) Refrigerator (b) Water cooler (c) Deep Freezer (d) Compare their cooling coils and other systems. To find out the rating (cooling rate) at different suction temperatures (temperature differences) and air handling capacity of the air cooling unit. Plotting the practical  refrigeration cycle on a pressure enthalpy diagram and to compare it with a theoretical refrigeration cycle. Study different parts and operation of a (a) Air washer (b) Room cooler, (c) Air  Conditioner (d) Chemical Dehumidifiers (e) Cooling. Plotting of psychrometric process :Sensible heating & cooling. Dehumidification & cooling and heating & humidification study of different humidity indicating, recording and controlling devices. Problems on cold storage. Visit to cold storage.


12.  Electrical Engineering                                                                                                                                                                               3 (2 + 1)

Alternating current fundamentals; Electromagnetic induction magnitude of induced E.M.F. alternating current, R.M.S. value and average value of an alternating current. Phase relations and vector  representation. A.C. series and parallel circuits, Concept of resonance, polyphase alternating current circuits, three-phase concept, Star and delta connections, star delta transformation, Energy measurement. Transformers: Fundamental of transformer, Theory vector diagram without load and with load, Losses, voltage regulation and efficienty of transformer, uto-transformer. Alternators : Elementary Principles, Construction and different types of alternators, E.M.F. in alternators, circuit breakers. Induction motors : Fundamental principles, production of rotating fields, construction, Rotor winding-squirrel cage and phase wound rotors, analysis of current and torque, starting of induction motor housing, selection of motor and its controls. D.C. Machines : Construction and operation of D.C. generator, types of generators, various characteristics of generator, D.C. motors, torque speed characteristics of D.C. motors, Starting and speed control of D.C. motors. Electric Power Economics : Maximum demand charge, Load factor and power factor correction. Measuring Instruments : Classification of instruments, elements of a generalized measurement system, static and dynamic characteristics.


Practical : Study of voltage resonance in L.C.R. circuits at constant frequency ; (a) Star connection-study of voltage  and current relation (b) Delta connection-study of voltage and current relation. Measurement of power in 3-phase circuit; (a) for balanced loads (b) For unbalanced loads, by wattmeter and energy meters. Polarity test, no-load test, efficiency and regulation test of single phase. Voltage and current relation in a 3-phase transformer of various kinds of primary and secondary connection systems. Starting of induction motor by the following starters : (i) D.O.L. (ii) Manual star- delta (iii) Automatic star – delta  (iv) Manual auto-transformer. Starting of slip-ring induction motor by normal and automatic rotor starters. Test on 3-phase induction motor, determination of efficiency, line current, speed, slip, power factor at various outputs. Determination relation between the induced armature voltage and  speed of separately excited D.C. generator. Magnetization characteristic of D.C. generator. Study the starter connection and starting reversing and adjusting speed of a D.C. motor. Study of various measuring instruments.


13.  Food Engineering                                                                                                                                                                                           4 (3 + 1)

Rheology of processed food, Properties of fluid foods, Rheological method, Measurement of rheological parameters. Properties of granular food and powders, Properties of solids foods, Visco-clastic models. Measurement of Food texture. Food Freezing : Thermal properties of frozen foods. Predication of freezing rates. Rank’s equation, Neumanna problem and Tao solution. Design of food freezing equipment, air blast freezers, Plate freezers and immersion freezers, Storage of frozen foods. Food dehydration : Estimation of drying time for food products, Constant rate period and falling rate period dehydration. Diffusion controlled falling rate period. Use of heat and mass balanced in analysis of continuous dryers, fixed tray dehydration, cabinet drying, tunnel drying. Freeze Dehydration : Heat and mass transfer, calculation of drying times, Industrial freeze drying Equipment for pulping, fruit juice extraction, Balanching, dehulling, size reduction and distillation.


Practical : Study of rheological properties of foods. Study of freezers and freeze dryers. Design problems on batch freezers. Design problems for continuous freezers Design problems on dryer. Visit to cold storage. Visit to food processing plant.