pilot layout 401
MODULE 1: EXPERIMENTATION IN PILOT LAYOUT
Size and Structure of the Pilot Plant
Definition of Pilot Plant: A pilot plant is a physical model that serves as a scaled-down version of the corresponding industrial unit, exchanging the full-size equipment for smaller versions at a ratio of 1/100 to 1/10. Its purpose is to facilitate experimentation in various domains related to food processing.
Areas of Pilot Plant Experiments
Market Survey: The pilot plant can produce a determined amount of a new product to gauge its acceptance, thereby assessing economic profitability.
Design Data: It enables the analysis of operation behaviors or unit processes under conditions that cannot be replicated in a laboratory.
Products and Raw Materials: Characterization of food products and the evaluation of raw materials during product development is executed.
Optimization Data: Assessing the optimization of an operational plant involves utilizing pilot plant data.
Basic Principles of Scaling
The primary criterion to determine the physical size and form of a pilot plant is the principle of similarity, introduced by Sir Isaac Newton. In fluid dynamics, three types of similarities must be maintained:
Geometric Similarity: The pilot plant must resemble the food processing plant in physical form or geometric relationships between the dimensions.
Kinematic Similarity: The velocity relationships in both setups must be consistent.
Dynamic Similarity: The relationships of forces in both environments must coincide, particularly in turbulence regimes for fluid handling.
Chemical Processes Similarities
When simulating chemical processes, additional similarities include:
Thermal Similarity
Chemical and Biochemical Similarity
Minimum and Maximum Size Considerations
Minimum Size: Determined by the smallest product amount necessary for quality analytical control.
Maximum Size: Limited by the product volume required for testing market acceptance.
Applications of Pilot Plants
Semi-commercial Plant: When sufficient product volumes for market testing are produced, it is termed a semi-commercial plant.
Types and Applications:
Product Studies: Focuses on quality characterization, influences of process conditions on product quality, new product development, and market acceptance studies.
Raw Material Studies: This involves the characterization of raw materials and the evaluation of their suitability for industrialization.
Process Technology and Engineering Studies: Optimizing process conditions for economic efficiency and product quality, evaluating process equipment alternatives, and developing new process technologies and equipment.
Auxiliary System Requirement Studies: Involves the assessment of mass and energy balances, food physical properties, energy recovery in process systems, and control system efficacy.
MODULE 2: ENGINEERING ECONOMY
Introduction
Definition of Engineering Economy: Engineering economy examines quantitative techniques to evaluate engineering alternatives based on financial criteria. Critical decisions in production systems engineering include:
Introducing new products, phasing out existing ones.
Selecting alternative production technologies.
Choosing plant locations and layouts.
Decisions regarding equipment replacement.
Important Terms in Engineering Economy
Key Concepts
Time Value of Money:
Defined as the value of money over time, affected by inflation and potential investment earnings.
Reasons why ₦1000 today is worth more than ₦1000 a year later:
Inflation
Risk
Cost of money
Inflation:
Refers to the fall in purchasing power due to economic factors.
Interest:
The fee charged for borrowing money.
Interest Rate:
The proportion of interest paid on a principal amount over a specified period, usually a year. Often expressed as a percentage per annum.
Compound Interest:
Interest calculated on the initial principal and also on the accumulated interest from previous periods, widely applied in business.
Rate of Return:
Ratio of net profit to the investment amount, assessing profitability.
Attractive Rate of Return:
The minimum acceptable rate of return used to evaluate investment proposals. Proposals below this threshold are often rejected.
Payment:
Any monetary outlay by a production concern for materials or services.
Receipt(s):
Any monetary income received from product sales or services.
Cash Flow:
The sequence of actual or estimated payments and receipts over time; depicted visually in cash flow diagrams.
Sunk Costs:
Past expenses irrelevant for current decision-making; they are fixed and unrecoverable.
Opportunity Costs:
The profits lost from not choosing an alternative investment.
Asset:
Valuable items that a production concern owns and utilizes.
Life of an Asset:
Divided into three types:
Actual/Technological Life: Duration fulfilling functions based on technological factors.
Accounting Life: Duration to recover investment through depreciation from profits.
Economic Life: Duration performing economically within efficiency parameters.
Depreciation:
A method of recovering asset investment over its accounting life through systematic annual deductions affecting taxable income.
Book Value of an Asset: The cost of an asset minus total depreciation charged.
Salvage Value: Estimated resale value of an asset at the end of its useful life.
Replacement:
The acquisition process either through purchase or leasing to substitute a retired asset.
Defender and Challenger:
In economic analysis, the existing asset (Defender) vs. the proposed new asset (Challenger).
Retirement:
The disposal of an asset either through sale or abandonment as scrap.
MODULE 3: METHODS OF ECONOMIC EVALUATION OF ENGINEERING ALTERNATIVES
Overview
There exist two primary categories of economic evaluation methods:
Undiscounted Cash Flow Methods
Discounted Cash Flow Methods
1. Undiscounted Cash Flow Methods
In these methods, future cash flows aren't discounted, effectively treating the discount rate as zero. While they are simpler, they serve primarily as preliminary evaluations.
Payback Period Method
This method calculates the duration until the investment amount is matched by the undiscounted profits. The option with the shortest payback is favored.
2. Discounted Cash Flow Methods
These methods account for the time value of money. Three distinct approaches fall under this category:
A) Net Present Value Method
Known as Net Present Worth, it assesses the total present worth of estimated receipts and expenditures at a defined discount rate. A positive NPV suggests the return exceeds the attractive rate of return, thus identifying the best alternative through maximum NPV value.
B) Equivalent Annual Cost Method
This technique derives a uniform series of payments that equates to the net present value of a series of cash flows. The alternative with the minimum equivalent annual cost is selected.
C) Rate of Return Method
This method calculates expected rates of return across alternatives, picking the option with the highest rate. This usually involves trial-and-error procedures to identify corresponding discount rates with acceptable NPV values.
Cost-Benefit Analysis
This is crucial for evaluating large governmental projects through a social lens.
Social Costs: Encompasses direct investment costs and collateral effects on the community, including social and ecological impacts.
Social Benefits: Involves not just direct revenues, but broader societal benefits, such as economic growth, job creation, and infrastructural development.
Procedure for Cost-Benefit Analysis
Identify potential project alternatives.
List relevant social costs and benefits for each alternative, ensuring comprehensive evaluation.
Assess costs and benefits using a monetary scale, preparing estimates for each project year.
Create a cash flow diagram based on evaluations, determining net social benefits via a social rate of return.
Select the alternative with the highest net social benefit or rate of return.
MODULE 4: MATERIALS OF CONSTRUCTION OF FOOD EQUIPMENT
Characteristics of Suitable Construction Material
Materials in contact with food and cleaning agents need specific properties:
Corrosion Resistance: Must withstand corrosive effects from food or cleaning agents.
Surface Finish: Needs to discourage dirt accumulation and avoid excessive surface roughness.
Mechanical Behavior: Must exhibit structural strength, resistance to abrasion, and cope with thermal and physical shock.
Types of Materials Used
Stainless Steel:
Preferred material in the food industry; AISI 304 is commonly used.
For foods with extreme conditions, AISI 316 or 316L provide better corrosion resistance.
Aluminum:
High thermal conductivity (~217 W/m·K) and weight (2700 kg/m³).
Corrosion resistance in certain contexts but unfit with strong acids or alkalis.
Nickel and Monel:
Previously favored until stainless steel emerged; Monel is notably used for better corrosion resistance in specific applications.
Plastic Materials: Commonly used for various applications in food processing, like packaging and equipment construction.
Key plastics include polypropylene, polyethylene, PVC, polyester, and epoxy resins.
MODULE 5: MAINTENANCE OF FOOD PLANT BUILDING
Maintenance Procedures
Importance of Painting
Enhances plant efficiency, extends material life, and boosts employee morale. Special paints are designated for various surfaces, ensuring durability against environmental factors.
Safety Color Code
A standard system for identifying safety hazards in work environments using colors. Common uses include identifying machinery hazards (orange), emergency equipment (red), and safety equipment (green).
Roof Inspection
Essential to inspect roofs twice annually; look for wear on roofing materials that can lead to leaks.
Care of Concrete Floors
Remove grease using mild cleaners; ensure pitting prevention through proper cleaning methods. Repair cracks effectively to maintain floor integrity.
Dust control methods and preventive actions against weather-related damage are identified.
MODULE 6: CLEANING & SANITIZATION
Overview
Cleaning and sanitizing is a fundamental aspect of food processing designed to remove contaminants and maintain a hygienic environment.
CIP Techniques
Key Components
Pre-rinsing: Utilizing cold water.
Alkali Wash: Often enhanced with sodium hypochlorite for effective cleaning.
Rinse Steps: Involves multiple rinse cycles, including acid rinses and final sanitization procedures.
Definition of Sanitation
Sanitation in food refers to maintaining hygienic conditions, employing scientific principles to reduce microorganism growth and ensure food is safe for consumption.
MODULE 7: PROCESS SCHEDULING
Importance of Scheduling
Critical for optimizing production efficiency and minimizing costs, scheduling allows for effective resource allocation, reducing the effort required for planning.
Production Scheduling Approaches
Forward Scheduling: Planning from resource availability to assignment deadlines.
Backward Scheduling: Planning from deadlines back to starting points, helping identify capacity adjustments needed.
Resource Allocation & Productivity
Outputs are contingent on the effective allocation of inputs among production processes to maximize efficiency. Algorithms assist in refined scheduling methodologies.
MODULE 9: ILLUMINATION AND VENTILATION
Importance of Illumination in Processing Facilities
Adequate lighting enhances workplace cleanliness and efficiency; essential for ensuring safety while working.
Recommended Levels of Illumination
Standards are maintained for varying functions within a facility to enhance productivity.
Types of Lighting
Fluorescent Lamps: Known for high efficiency, used widely unless frequent on/off cycles are required.
Incandescent Lamps: Less efficient but occasionally used in specialized settings (e.g., high-moisture areas).
Ventilation Standards
Adequate air supply is crucial for maintaining a productive processing environment; often requires special systems to manage air quality effectively.
The air exchange rate may vary based on processing demands (6 to 20 times per hour) ensuring a consistent supply of fresh air.