BVT-Merkblatt zu Abwasser- und Abgasbehandlung

Annexes
­ no dilution of the effluent
­ exceptionally high discharges (e.g. in case of maintenance) have to be smoothed over
24 hours
­ effluents need to be monitored, connections periodically inspected. The local authority
can monitor the effluent on their own initiative and check the monitoring equipment in
cooperation with the industrial operator.
­ water consumption is monitored and the results sent to the local authorities
­ action plan for an emergency (e.g. the closure of connections between municipal sewage
system and industrial site)
� the obligations of the local authority are:
­ to accept the discharge when it is within the limits fixed in the agreement
­ to inform the industrial site in the case of operational problems at the municipal
WWTP
� economic and administrative questions
Example of Cooperation Between Municipal and Industrial WWTP with Positive Synergetic
Effect (Germany)
In Section 1.3.2.1, it was mentioned that there are normally neither advantages nor disadvantages
with the joint treatment of industrial and municipal waste water. An example where this
is not the case is described briefly here.
In the past, two WWTPs – one a municipal and the other a chemical industry plant – each operating
a central biological treatment, had separate discharge points into a small receiving river.
They now operate jointly in the following manner:
� nitrogen-rich and poorly degradable filtrate from sludge treatment devices of the municipal
WWTP is treated in the industrial WWTP, which has micro-organisms adapted to cope
with this kind of waste water
� in return, the industrial WWTP sends an equal amount of waste water to the municipal
WWTP
Abbildung 7.1 and Abbildung 7.2 show, respectively, the processes before and after the move
to joint operation.
This cooperation has economic and environmental advantages. The use of equipment on only
one site saves capital and the mutual discharge reduces the nitrogen load (sum of ammonium,
nitrite and nitrate) into the receiving river by 1000 kg per day, compared to the separated discharges
before.
7.2 Annex II. Example of EFMA: Pinch Technology
A widespread and well known EMFA tool is Pinch technology, used to optimise production
processes, save energy and water consumption and decrease the impact of waste discharge.
Two of those – the optimisation of water consumption and waste discharge – are within the
scope of this BREF. Optimisation of production processes is covered by vertical BREFs and
other references [cww/tm/132].
Pinch Technology is a methodology for optimising the consumption of consumables in processes
and on sites by introducing process integration techniques. It was primarily used as an
energy saving tool to improve thermal efficiency in the chemical and process industries. Recently
this method has been transferred to water and waste (water) minimisation.
322 Waste Water and Waste Gas Treatment