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The objectives of this project were the development and the test of an alternative technology for the purification of mercury containing waste water from dental surgeries.
At first, comprehensive
investigations for the preparation of Hg-specific SGS-polymers
were carried out. Afterwards, the test of these polymers for the filtration
and sorption of residual substances (Hg, Ag and Sn), which were contained
in the waste water, as well as possibilities of the selective recovery
of recyclable materials during the regeneration processes were considered.
Different technological
suggested solutions were developed. Currently, one of them is tested in
a dental surgery in Berlin.
The project runs from the October 1st, 1997 until the March 31st,1999 and is funded by the Senatsverwaltung für Stadtentwicklung, Umweltschutz und Technologie of the state of Berlin and by the European Fund for Regional Development.
The aim of this project was the development of an ion-exchange method for the softening of well water by using compact SGS-polymers. Therefore, investigations of the deposition of hardness-producing calcium and magnesium ions from drinking waters on cartridge-shaped filter elements were carried out in the laboratory scale.
The sorption process on the SGS-polymer type 80 was investigated in dependence on flow velocity ranging from 470 to 1200 bed volumes/h. The sorption capacity reaches values up to 2.0 mval/g. The regeneration is realised by sodium sulphate solution, which can be re-used. The result of the investigations was the development of a nearly waste free technology for water softening.
The investigations
were carried out from September 1993 until May 1994. The IEG mbH Reutlingen
supported the investigations.
During a restoration project, investigations of mercury removal from solids containing washing waters were carried out. Therefore, comprehensive investigations of the filtration, sorption and elution of elemental mercury as well as mercury compounds in a dissolved and solid form were carried out on SGS-polymers. As a result a two-stage procedure (stage 1: filtration of the solids, stage 2: removal of the dissolved elemental mercury and dissolved mercury compounds) was developed. A pilot pant based on this procedure was constructed. Tests under real conditions showed, that the suggested procedure is applicable for the removal of mercury from industrial wash solutions. The compliance with the permitted limit values for waste water dumping in the sewer was proved.
The pilot test
was carried out from October 1994 until July 1996 in co-operation with
the Buna Sow Leuna Olefinverbund GmbH. It was financed by Utt ltd and co-financed
by funds from the project "Modellprojekt Buna zur Sanierung einer Quecksilber-Altlast".
Water of varying chemical
composition comes up during the restoration of former uranium mining areas
in the states of Saxony and Thuringia. This water has to be purified due
to increased concentrations of harmful substances.
On instructions of the
ÖKOTEC Institut für angewandte Umweltforschung GbR the Utt GmbH
carried out a feasibility study of the SGS-polymers applicability for the
removal of uranium from contaminated water.
As a result of laboratory investigations on SGS-polymer type 11 a purification procedure for low uranium-contaminated water was suggested. In co-operation with the Wismut Ltd the applicability of this procedure could be proved in two field tests.
The investigation was carried
out from May 1996 until October 1996.
The ground water
in the surroundings of former military used areas is contaminated by explosives
and their degradation products.
In co-operation
with the university of Leipzig pre-investigations were carried out in the
aim of removing such substances from the ground water by adsorption processes
on SGS-polymers. Therefore, the adsorptive properties of some frequently
in soil and ground water found compounds (e.g. nitrotoluenes, nitrobenzenes
and aminonitrobenzenes) on SGS-polymers were investigated.
The project run from September 1995 until August 1997.
Due to promising
pre-investigations a collaborative project is planned for the continuation
of the investigations. The objective of the planned project is the purification
of explosive contaminated ground water by a combining procedure of filtering
and microbiological processes.
As a result of industrial activities of the mankind radioactive contaminated soil can be found at a lot of industrial sites.
On instruction of the Senatsverwaltung für Stadtentwicklung, Umweltschutz und Technologie of the state of Berlin a mixture of soil and rubble from a building site should be purified to a defined degree.
At first the Utt GmbH carried out some basic investigations concerning the mobilisation in laboratory scale. Afterwards the Utt GmbH developed the THORAC-process on the base of these basic investigations in co-operation with the Horn & Müller Ingenieurgesellschaft für Verfahrenstechnik und Abfallwirtschaft. The THORAC-process is a combined procedure of mixing, classifying and sedimentating under defined leaching and elutriating conditions. By using this procedure a concentrate containing the most of the radioactivity can be separated from the contaminated material. The concentrate mass amounts to 10 - 15 % of initial waste mass. The residual main part has a low concentration of radioactivity, therefore, it can be deposit at a disposal site.
The procedure was tested in a pilot plant and the process was technologically optimised. It could be also proved that the process is applicable for the purification of contaminated soil from other locations.
The developed purification method was applied for a patent.
The project run
from June 1997 until January 1998.
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