Energy Analysis of Beer Production

ENERGY ANALYSES OF BEER PRODUCTION PROCESS IN NIGERIA

ABSTRACT

In this study the energy consumption pattern for the processing of beer were estimated for a Nigerian brewery in order to determine that operation necessary for energy efficiency improvement. The production process was divided into thirty-two essential unit operations and grouped into four main group operations which are; Silo house, Brew house, Filter room and Packaging house respectively. Having analysed the energy data based on an input of processing a batch of 6.3 tonnes brew grains, the average energy intensity of the process to produce 467 hl of beer upon estimation was 159.84 MJ/hl with electrical (8.52%), thermal (91.06%) and manual (0.42%) of the total energy. The most energy intensive group was identified as the packaging house followed by the brew house with energy intensities of 108.12 MJ/hl and 50.12 MJ/hl respectively.

Key words: energy, energy intensities, thermodynamic analysis, beer.

NOMENCLATURE

Cp heat capacity (J/kg K)

Cf calorific value of fuel (J/kg)

Em manual energy (J)

Ep electrical energy (J)

Et thermal energy (J)

h specific enthalpy (J/kg)

H enthalpy (J)

I inefficiency

N number of persons involved in operation

P rated equipment power (kW)

p pressure (kN/m2)

Rs production of entropy (J/K h)

S entropy (J/K)

s specific entropy (J/kg K)

t time (h)

T temperature (K)

w mass flow rates (kg/h)

W work per unit time (W)

Wf quantity of fuel (l)

xs weight fraction (kg/kg)

η power factor (assumed to be 0.8)

γ fuel exergy grade function

ψ ratio of exergy in products to total exergy input

Subscripts

f fuel

i denotes the number of unit operation

j denotes type of energy (j = 1 represents electrical energy, j = 2, manual energy, j = 3,

thermal energy)

k section of plant; entrance or exit stream

Ɩ heat exchange surface (Ɩ in , input; Ɩ out , output)

Ɩ w liquid water

m manual energy

o...