This industry functions on a seasonal demand and so displays a wide variation in the Beverage to Fuel ratio. Typically, a good Beverage to Fuel ratio is achieved only for 4 to 5 months in a year.
For steam generation, boiler fuel accounts for a major amount of the total utility cost; the rest being attributed to water and electricity. A large proportion of steam in the beverage industry is utilized in Bottle washing, Pasteurizing and Syrup making units. In the Bottle washer section, steam is used essentially for the purpose of heating and cleaning.
Forbes Marshall- CII joint studies reveal differences in fuel consumption per Litre of beverage within the industry, i.e. Specific Fuel consumption (SFC).
A global soft drink manufacturers India facility, embarked on a mission to improve its Beverage to fuel ratio and thus under went an energy audit to identify the avenues. The audit identified a potential to improve the beverage to fuel ratio from 45 to 65 lt/lt F.O.
By implementing the audit recommendations:
- Steam to Fuel ratio improved by about 12%
- CRF improved from 74% to 80%
The above audit presented a potential savings in excess of Rs.20 lacs/yr. Additionally it also allowed the plant to deliver on internal global policy decisions.
The prime reasons for difference in SFC across plants were:
1. Efficiency of steam generation
Avg Direct efficiency : 68.2%
Avg Indirect efficiency : 71.1%
Reasons for gap:
- Fluctuating steam demand; load can go down to less than 25% of the capacity. This occurs when the bottling plant only is in operation.
- The excess air parameters are not monitored regularly in most plants, leading to increased flue gas losses.
2. Optimized steam distribution and utilization
1. Line size esp. for processes like pasteurizers and evaporators not based on peak loads.
2. Selection of appropriate pressure reducing stations to provide steam at recommended pressures to heat exchangers and evaporators.
3. Correct trap selection and sizing
3. Recovering condensate and flash steam
1. In most plants flash steam is not recovered.
2. 80% of beverage plants recover condensate from equipment but poor condensate recovery from bottle washers, hot water generation system and CIP section.
4. Capacity utilization
Most food and beverage plants being seasonal in nature, the plant capacity utilization fluctuates over the months. However the boiler operations are not optimized to the reduced loads. Additionally the equipment operation can also be sequenced to enable efficient operation.