FOOD PLANT UTILITIESThe principal p

FOOD PLANT UTILITIES
The principal plant utilities in a food plant are process water, process
steam, electric power for motors and lighting, and fuel.
Process Water
Process water is required for washing the raw materials and for various
cooling operations. In fruit and vegetable processing plants, water may be used
for transportation (fluming) of the raw materials from receiving to processing
areas. Water used in steam boilers may require ion exchange treatment to reduce
its hardness. Total water requirement in fruit and vegetable processing may range
from 5 to 15 m3 / ton of raw material.
2. Steam
Steam boilers are needed in most food processing plants to provide
process steam, used mainly in various operations, such as heating of process
vessels, evaporators and dryers, sterilization, blanching, and peeling. A medium
size food plant (80 tons / day raw material) may require a boiler producing about
10 tons/h of steam at 18 bar pressure.
Two principal types of steam boilers are used in the food processing
industry, i.e. the fire-tube and the water-tube boilers. The fire tube boilers operate
at relatively lower pressure (1–24 bar) and produce cleaner steam. The watertube
units operate at higher pressures (100–140 bar) and they are suited for cogeneration,
i.e. electrical power and exhaust steam of lower pressure for process
heating. Co-generation is economical in large food plants, requiring large amounts
of low-pressure steam, e.g., beet sugar plants.
A standby steam boiler of proper capacity may be necessary to provide
process steam during any boiler failure or breakdown.
Steam boilers are rated in Btu/h, kW or boiler HP (1 Btu/h = 0.293 W, 1
boiler HP = 9.8 kW). The heat flux in the boiler heating surface is about 0.75 k W/
m2. The boiler efficiency is about 85% with most of the thermal losses in the dry
gases and the moisture. Steam generation is about 1.4 t/h per MW.
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In order to maintain the concentration of accumulated dissolved solids in
steam boilers below 3500 ppm, periodic discharge of hot water (blow down) is
practiced.
Fuel is used in food plants mostly for generating process steam and
process drying. Natural gas and liquefied propane (LPG) are preferred fuels in
food processing, because their combustion gases are not objectionable in direct
contact with food products. Fuel oil and coal can be used for indirect heating, i.e.
through heat exchangers.
Culinary steam of special quality is used when steam is injected in food
products. The steam must be free of objectionable chemicals used in boilers,
which may be carried into the food being heated. Culinary steam is usually
produced from potable water in a secondary system of a heat exchanger heated
with high pressure industrial steam.
3. Electricity
Electrical power in food processing plants is needed for running the motors
of the processing, control, and service equipment, for industrial heating, and for
illumination. For a medium size food plant processing about 100 tons/day raw
materials, the power requirement may of the order of 500 kW. A standby power
generator of about 200 k VA is recommended for emergency operation of the
main plant, in case of power failure or breakdown.
Single-phase or three-phase alternating current (AC) of 110 V (60 cycles)
or 220 V (50 cycles) is used in food processing plants. The electrical motors are
either single-phase or three-phase squirrel cage.
Energy-efficient electrical motors should be used in various food
processing operations. A measure of the efficiency of electrical power is the
power factor (pf), defined as pf = kVA
kW
, which should be equal or higher than
0.85.
Illuminating (lighting) of industrial food plants should utilize fluorescent
lamps, which can save significant amounts

Results (English) 1:

FOOD PLANT UTILITIESThe principal plant utilities in a food plant are process water, processsteam, electric power for motors and lighting, and fuel.Process WaterProcess water is required for washing the raw materials and for variouscooling operations. In fruit and vegetable processing plants, water may be usedfor transportation (fluming) of the raw materials from receiving to processingareas. Water used in steam boilers may require ion exchange treatment to reduceits hardness. Total water requirement in fruit and vegetable processing may rangefrom 5 to 15 m3 / ton of raw material.2. SteamSteam boilers are needed in most food processing plants to provideprocess steam, used mainly in various operations, such as heating of processvessels, evaporators and dryers, sterilization, blanching, and peeling. A mediumsize food plant (80 tons / day raw material) may require a boiler producing about10 tons/h of steam at 18 bar pressure.Two principal types of steam boilers are used in the food processingindustry, i.e. the fire-tube and the water-tube boilers. The fire tube boilers operateat relatively lower pressure (1–24 bar) and produce cleaner steam. The watertubeunits operate at higher pressures (100–140 bar) and they are suited for cogeneration,i.e. electrical power and exhaust steam of lower pressure for processheating. Co-generation is economical in large food plants, requiring large amountsof low-pressure steam, e.g., the beet sugar plants.A standby steam boiler of proper capacity may be necessary to provideprocess steam during any boiler failure or breakdown.Steam boilers are rated in kW, Btu/h or boiler HP (1 Btu/h = 0293 W, 1boiler HP = 9.8 kW). The heat flux in the boiler heating surface is about 0.75 k/WM2. The boiler efficiency is about 85% with most of the thermal losses in the drygases and the moisture. Steam generation is about 1.4 t/h per MW.45In order to maintain the concentration hand of dissolved solids ' accumulated insteam boilers below 3500 ppm, periodic discharge of hot water (blow down) ispracticed.Fuel is used in food plants mostly for generating process steam andprocess drying. Natural gas and liquefied propane gas (LPG) are the preferred fuels infood processing, because their combustion gases are not objectionable in directcontact with food products. Fuel oil and coal can be used for indirect heating, i.e..through heat exchangers.Culinary steam of special quality is used when steam is injected in foodproducts. The steam must be free of objectionable chemicals used in boilers,which may be carried into the food being heated. Culinary steam is usuallyproduced from potable water in a secondary system of a heat exchanger heatedwith high pressure industrial steam.3. ElectricityElectrical power in food processing plants is needed for running the motorsof the processing, control, and service for industrial equipment, heating, and forillumination. For a medium size food plant processing about 100 tons/day rawmaterials, the power requirement may of the order of 500 kW. A standby powergenerator of about 200 k VA is recommended for emergency operation of themain plant, in case of power failure or breakdown.Single-phase or three-phase alternating current (AC) of 110 V (60 cycles)or 220 V (50 cycles) is used in food processing plants. The electrical motors areeither single-phase or three-phase squirrel cage.Energy-efficient electrical motors should be used in various foodprocessing operations. A measure of the efficiency of electrical power is thepower factor (pf), defined as pf = kVAkW, which should be equal or higher than0.85.Illuminating (lighting) of industrial food plants should utilize fluorescentlamps, which can save significant amounts