July 1, 2004, posted to KBC
invention offers water solution
The Budapest Sun
Maros utca 12, II. em.
Fax: (36-1) 489-4344
An almost 20-year-old but still
unused invention by a Hungarian could provide a
cost-efficient solution to both the elimination of
sewage sludge and the fertilization of the soil,
says Mihaly Kohler, owner of the patent.
Kohler promises the process will not require
additional pharmaceutical products.
"After the use of this fertilizer, the plants will
be so rich in mineral elements that it will not be
necessary to complement the food with pharmaceutical
products," Kohler, a former professor at the current
Agriculture Center of the Debrecen University told
The Budapest Sun.
In addition, the usage of sewage sludge, otherwise
treated as hazardous waste, relieves municipalities
of the burden of get rid of the smelly substance.
process makes use of ryolite tufa, a volcanic
mineral found in abundance in the Zemplen
Mountains in northeast Hungary.
The mineral is used
primarily in the construction industry, but the
leftovers have been extensively utilized in
"Approaching agriculture from the environmentally
conscious side, I started to look into how ryolite
could be useful in treating communal waste waters,
sewage sludge and manure and turning them into
fertilizers," Kohler said.
In the European Union, 50-90% of sewage sludge is
recycled, albeit via a different method.
In Hungary, the sewage drains away to the
countryside where it is often untreated in most
A striking example of an untreated
sewage flow is the exit of the underground pipeline
excreting its content straight into the Danube next
to Erzsebet hid.
"With this treatment method, small settlements could
resolve their sewage problems, and at the same time
could produce nurturing stuff for their soil.
"The end result is
water without any smell and sufficiently clean for
irrigation," said Kohler, whose invention took 18
years to bring to fruition.
The sewage sludge-based fertilizer is currently
under production in Miskolc where the local
waterworks started the manufacturing in neighboring
The product is
delivered in powder form, and can be used for all
sorts of field crops, vegetables, fruits and flowers
without any further fertilization.
"The organic litter is turned into minerals by the
microorganisms in the soil, then the minerals are in
turn processed by the plants.
"That way by consuming the plant, humans have
sufficient source of minerals and no further food
complements are necessary," said Kohler when
describing the cycle.
ryolite phase can be added to modern large-scale
sewage treatment processes, the method
works best for small settlements.
Copyright 2004, The Budapest Sun