EARLIER KITCHENS

PRESENT DAY KITCHEN

Common misconceptions of kitchen ventilation. In a commercial kitchen the prime concern of the owners, designers, and managers is more often is that the cooking appliance and food production machinery directly produce saleable products and therefore earn revenue so are at the top of a priorities list.

A ventilation system is usually at the bottom of priorities as it consumes revenue and does not provide direct earning. Kitchen ventilation is perceived as a “necessary evil” and is provided with the cheapest form to satisfy the plan or statutory requirements. Common misconceptions of kitchen ventilation.

WHY DO WE NEED A VENTILATION SYSTEM IN COMMERCIAL KITCHENS ? 1. Remove excess heat immediately 2. Remove particulates of grease, odour, Toxic gases Remove moisture 4. Renew the air that is being exhausted while maintaining Indoor air quality in the working space.

WHERE DOES THE HEAT GENERATED IN KITCHEN COME FROM ? MAINLY FROM ‘COOKING PROCESS’ and COOKING EQUIPMENT. Convective heat can be captured by a hood. Radiated heat cannot be captured by any hood. 1. Convective Heat 2. Radiated Heat

What happens when we don’t exhaust effectively ? EFFULENT AND HEAT SPILLS

9 Heat Gain Model Capturing Radiation Convection Radiation Spilling Radiation

Captured by Schlieren Thermal Imaging = Heat + Humidity + Toxic Gases

SPILLING ADDS

EFFECTS OF SPILLING Productivity Health There are several studies dealing with cooking and health issues. It is confirmed that cooking fumes contain hazardous components in both Western and Asian types of Kitchen.

Kitchen workers may be exposed to a relatively high concentration of airborne impurities and that they are potentially exposed to relatively high levels of mutagens and carcinogens.

EFFECTIVE REMOVAL

Advantages of Good Kitchen Ventilation System Avoids Health & Hygiene Risks Avoids Health & Hygiene Risks Keep kitchen staff comfortable Keep kitchen staff comfortable Prevents Fire Accidents in Kitchen Prevents Fire Accidents in Kitchen Improves the Life of Kitchen Equipment Improves the Life of Kitchen Equipment Prevents food contamination Prevents food contamination

Kitchen Ventilation System consists of Kitchen Hood Kitchen Hood

Kitchen Ventilation System consists of Centrifugal Blower Centrifugal Blower

Kitchen Ventilation System consists of Exhaust Ducting Exhaust Ducting Exhaust Duct

Kitchen Ventilation System consists of Make Up Air Unit Make Up Air Unit

Kitchen Ventilation System consists of Fresh Air Ducting Fresh Air Ducting Supply air grill

Energy Consumed Kitchen Ventilation consumes 30% of Energy in a Restaurant. Kitchen Ventilation consumes 30% of Energy in a Restaurant. 1 HP of Current consumed in a Commercial Kitchen costs Rs. 25,000 per annum. 1 HP of Current consumed in a Commercial Kitchen costs Rs. 25,000 per annum. An average Restaurant Ventilation consumes 20 Hp. An average Restaurant Ventilation consumes 20 Hp.

How do we save energy in Commercial Kitchen Ventilation

Selection of Right Kitchen Hood Selection of Right Kitchen Hood Selection of Right Blower Selection of Right Blower Right Duct Designing Right Duct Designing Selection of Right Fresh System Selection of Right Fresh System Demand Ventilation Demand Ventilation

Selection of Right Kitchen Hood

Maximum Hangover Maximum Hangover

Selection of Right Kitchen Hood Maximum Capture Area Maximum Capture Area

Selection of Right Kitchen Hood Minimum Mounting Height Minimum Mounting Height

Selection of Right Kitchen Hood Side Panels Side Panels Side (or end) panels or skirts permit a reduced exhaust rate in most cases, as more of the replacement air is drawn across the front of the equipment, improving capture of the effluent plume generated by the hot equipment. Another benefit of end panels is to mitigate the negative effect that cross drafts can have on hood performance. Side (or end) panels or skirts permit a reduced exhaust rate in most cases, as more of the replacement air is drawn across the front of the equipment, improving capture of the effluent plume generated by the hot equipment. Another benefit of end panels is to mitigate the negative effect that cross drafts can have on hood performance.

Selection of Right Kitchen Hood Minimum Filter Pressure Drop Minimum Filter Pressure Drop

Selection of Right Kitchen Hood Avoid Dampers Avoid Dampers

Selection of Right Kitchen Hood Insulation of Fresh Air Plenum Insulation of Fresh Air Plenum

Selection of Right Kitchen Hood Right collar sizing. Right collar sizing.

Selection of Right Kitchen Hood Coanda Effect Coanda Effect

Selection of Right Kitchen Hood Capture Jet Concept Capture Jet Concept

Selection of Right Kitchen Hood Deflection Lip Concept Deflection Lip Concept

Selection of Right Kitchen Hood Ultra Violet Filter Bank in Hood Ultra Violet Filter Bank in Hood

Selection of Right Kitchen Hood Spray mist concept Spray mist concept

Selection of Right Blower Backward Inclined Blades Backward Inclined Blades

Selection of Right Blower Direct Drive Direct Drive

Selection of Right Blower Low RPM of Motor Low RPM of Motor

Selection of Right Blower Performance Curve Efficiency Performance Curve Efficiency

Selection of Right Blower Discharge Orientation of Blower Discharge Orientation of Blower

Right Duct Design Minimizing Bends Minimizing Bends

Right Duct Design Large Radius for Bends Large Radius for Bends Changes of direction should be by easy bends and well-rounded corners, not by sharp elbows, unless fitted with guide vanes.

Right Duct Design Maintaining Right aspect Ratio Maintaining Right aspect Ratio

Right Duct Design Proper Joints to avoid duct leakage Proper Joints to avoid duct leakage

Right Duct Design Suggest Angle Frames for Large Ducts Suggest Angle Frames for Large Ducts

Right Duct Design Proper sizing of Duct for Blower inlet connection Proper sizing of Duct for Blower inlet connection

Right Duct Design Proper sizing of Duct for Blower Outlet Connection Proper sizing of Duct for Blower Outlet Connection

Right Duct Design Proper insulation of Fresh Air Ducts Proper insulation of Fresh Air Ducts

Right Duct Design Auxiliary items, such as grilles, louvers, filters. These items should be large enough to keep air velocities through them down to a reasonable level, consistent with the velocity in the main duct.

Selection of Right Fresh Air Unit Low Static Pressure Units as Kitchen is in Negative pressure Low Static Pressure Units as Kitchen is in Negative pressure

Selection of Right Fresh Air Unit 20 Microns Filtration more than sufficient 20 Microns Filtration more than sufficient

Selection of Right Fresh Air Unit Placement of Unit as near to the Kitchen as possible Placement of Unit as near to the Kitchen as possible

Selection of Right Fresh Air Unit Consider evaporative air cooling option to Air conditioning in dry Areas Consider evaporative air cooling option to Air conditioning in dry Areas

Demand Ventilation System Senses Temperature in Hood Gives signal to the blower to increase or decrease speed Give signal to the Fresh Air Unit to match exhaust blower Done through VFD based Drive

Compensating Wall Mounted Hood Fresh Air Exhaust Air

Fresh Air Exhaus t Air Flat Oval Duct ExhaustDuct Exhaust Duct Fresh air collar Island Compensating Hood