7
NEW CONTRACT
SIGNED
Methane
Quite a lot of water is needed to brew beer. For one litre
of beer an average of seven to ten litres of water is requi
red. Modern breweries use least water, the older ones
use slightly more.The pollution of waste water is caused
by what is referred to as "extract loss" .These are residues
which are released during beer production, for instance
when the brewery is being cleaned. What does Heineken
do with that waste water? Achat with Mr. Klijnhout of
the Water and Environment Department (the effluent
specialist at HTB's Central Research).
Buffer tank
technologically) and, with it being a
decomposition process, there is a risk
of foul smells. Besides, anaerobic
purification works best at 30 to 35
degrees Celsius. If the waste water has
first to be heated to that temperature,
a lot of energy will be needed.
Anaerobic purification works best
when there is a uniform supply of an
(almost) constant quality of waste
water. At a brewery the supply usually
varies. "To solve that problem you
need a buffer tank to equalise the flow
of waste water from the brewery, and
building such a buffer tank is a costly
business", says Mr. Klijnhout.
Naturally, both systems also have their
advantages. "An aerobic system
almost always works. You don't, as it
were, have to keep an eye on the
aerobic process itself. The advantage
of an anaerobic installation is the
limited space it occupies compared to
an aerobic process. Besides, less
excess sludge is produced. However,
in return, you also get a limited degree
of purification. The choice between
aerobic and anaerobic will mainly be
determined by the local circumstances
in the brewery", concludes Mr.
Klijnhout.
Just one example: the aerobic
purification plant installed at the El
Aguila brewery near Madrid in Spain
proved to be too small. An anaerobic
plant, which is currently being started
up, has been constructed upstream of
it.The experience being gained in
Madrid and in other locations will
certainly be of great value to the
Heineken group of companies as a
whole.
Since 1987 Heineken has been doing business with the Soviet Union. Every
year Heineken negotiates a new contract for the following year with the
central purchasing organisation Vneshposyltorg for the quantities of beer,
soft drinks and distilled products to be delivered and the price. Also for 1988 a new
contract was concluded. Mr. Kondratjev of Vneshposyltorg visited Holland late last
year in order to have the contract signed. A rather significant part of the deliveries for
this year will consist of soft drinks. These soft drinks are produced by Vrumona,
Heine ken's soft drink factory.
Heineken has built a number of bars in several cities in the Soviet Union. In these bars
Heineken beer and the other contracted products are being sold. Part of the deliveries
goes to these bars. Another part is destined for the big international hotels and tourist
shops.
From left to right (sitting): Export Director J. van der Zee, V.P Kondratjev, Vice
President Vneshpolytorg, A.S. Peshkov, member of the Trade Representation of the
USSR in the Netherlands(standing) J.M. Holthuizen, Managing Director Peja
Export B. V (our agent in the Soviet Union), K. Brandt, Regional Export Manager
and E.N. Bakker, Area Export Manager.
Anaerobic purification is in fact a sort
of controlled rotting. So it does not
require any air (oxygen). During the
process a gas is formed which consists
mostly (but not entirely) of methane.
Methane is a combustible gas which
means a source of energy. Isn't it
possible to make use of that energy?
"It's a very appealing idea of course,
but the quality of the gas emitted is not
yet suitable for that; it is too wet and
still contains some unwanted
pollutants", says Mr. Klijnhout.
Both forms of water purification have
a substantial number of drawbacks.
"For aerobic purification you need a
big installation which requires a lot of
energy (for the aeration) and
produces a lot of excess sludge. In
fact, most of the pollution is converted
into bacteria (excess sludge). Quite
large amounts are produced and these
have to be properly disposed of: after
all, we have the Heineken name to live
up to!" An added drawback is that
aerobic purification may lead to
secondary environmental problems,
such as noise, smells and flies.
The five (anaerobic) reactor vessels in
the pre-treatment plant near the El
Aguila brewery inAlgete. Buffer tanks,
services building and aerobic
purification are not visible on the
picture.
Part of the (aerobic) water purification
plant in Zoeterwoude. Activated sludge
carries out its useful work in these tanks.
Purifying waste water
with or without oxygen?
At Heineken care for the waste water only when it can no longer
environment is of have any adverse effects on the
paramount importance. environment. "At the moment we are
More and more operating companies basically faced with a choice between
are taking steps to discharge their aerobic and anaerobic purification.
Both systems have great benefits but
they also have their drawbacks",
explains Mr. Klijnhout.
In aerobic waste water purification the
effluent in the water is broken down
by bacteria which breathe oxygen and
live in what is known as activated
sludge.This activated sludge "digests"
the effluent in the waste water, leaving
clean water behind. Aerobic means
that air (oxygen) has to be introduced
into the process and this costs money.
Activated sludge grows in volume
during the purification process; the
excess sludge has to be removed.
That's an expensive operation!
Aerobic purification takes up a lot of
space and is a costly process in all
respects, but it is one that produces a
very good quality of purified waste
water without problems: water that is
even drinkable!
Anaerobic purification, too, has its
disadvantages. Although the process
is fast-acting, it only gives a limited
degree of purification. It is a highly
complex process (both technically and
