Projects-Archive
Migration of heavy metals from
devices of drinking water heating
systems
| Colleague: | Dr. Ing. Karin Rühling, Dipl.- Ing.(FH) Knut Gietzelt |
| Co-operation: |
IKS Dresden |
| Financing: | DVGW; AGFW; Industry |
| Duration: | 12/05 - 03/2009 |
Abstract
The new Drinking Water Ordinance is coming into effect in 2003. Since that time the regulations and threshold values are valid likewise for cold and hot drinking water.
Therefore the modification of the drinking water quality, especially the migration of heavy metals, during the path through the domestic installation
and the drinking water heating system respectively) is important.
Currently secured technical expertises are only available for materials and alloys which are certified via DIN 50931-1 under cold drinking water conditions.
During the construction of the novel testrig was finished, so that the migration of the heavy metals cooper, nickel and lead is possible for several kinds
of devices of drinking water heating systems could have been assessed.
The plant testrig consists of three parallel drink water test tracks:
• Test track 1 – reference track for migration in domestic water (cold)
• Test track 2 – drinking water heating system without circulation
• Test track 3 – drinking water heating system with circulation
The results are available for two 26-weeks-test runs. Plate heat exchangers (stainless steel) and warm water meters were tested.
The comparative field tests were carried out as a complete S0, S1 and S2-sample at the last tapping point at customer side.
The sampling was carried out according to the recommendations of the German Federal Environmental Agency (UBA) and was likewise carried out separately
for cold and hot drinking water conditions. The analysed heavy metal migration values from the hot water side partly exceed the values for the cold water condition significantly.
Railway switch heater system by
means of renewable energy sources
| Colleague: | Dr.-Ing. Bernd Müller, Dipl.-Ing. Lutz Dittmann |
| Co-operation: |
HERMOS Systems GmbH, Dresden; Rochhausen Kältesysteme
GmbH, Scharfenstein |
| Financing: | BMWA, (AiF-ProInno) |
| Duration: | 01/07 - 02/2009 |
Abstract
During report period TUD’s
activities on the project had been finished according to
plan. Involved companies now are able to complete
the reconstructed railway switch heater system at the Hermos
company area as a test rig and illustrative model to carry out
tests during winter 2009/2010.
The delay in the extensive project depended on difficulties
mentioned in last year’s report.
The results of the project were honoured and the activities
within the project supported by leading employees of DB, the
potential user of the developed system.
Decrease of losses from circulation
in central heating installations for drinking
water
| Colleague: | Dipl.-Ing. Robert Huhn, Dipl.-Ing. (FH) Knut
Gietzelt |
| Co-operation: |
ILK Dresden |
| Financing: | BMWA, (AiF-ProInno) |
| Duration: | 06/05 - 08/2007 |
Abstract
The heating demand for buildings decreases due to official
laws (i.e. EnEV) requiring im-proved insulation and efficient
heat generation devices.
Thus the share of energy used for preparation of domestic hot
water (DHW) and especially for covering the circulation losses
receives increased importance.
Measurements at three residential buildings in Dresden show a
very low demand of DHW and therefore very high relative
circulation losses.
This project contains complex analyses of different hot water
circulation systems and there integration in local or district
heating systems or in
decentralized thermal supply systems (heating boilers, heat
pumps, CHP, solar systems). The primary energy demand of the
supply chains is to evaluate.
Thermal, hydraulic and energetic data are continuously
measured in the three buildings. A test rig for examination of
dynamic processes in
hot water circulation systems and for testing new hydraulic
configuration and devices for covering the circulation losses
is installed at TU Dresden.
The practical results will help to derive new specifications
for improved circulation systems and its operation.
air/water – heat pump with
alternative heat source at lowly outside temperature;
Theoretical research into
peak-load-heat-sources
| Colleague: | Dipl.-Ing. Klaus Ramming |
| Co-operation: | Lattermann Haustechnik GmbH |
| Financing: | BMWA, (AiF-ProInno) |
| Duration: | 09/05 - 08/2007 |
Abstract
The aim of the project is the development of a peak load
heat source for heat pump applications as well as a
numerical simulation program and an analytical dimensioning
tool for horizontal heat collectors in general.
The results of the experiment to support the peak load heat
collector with short heat pipes, which should transport
heat from deeper layer of earth up to the collector, were not
satisfactory. The efforts were much higher than the
effects.
Despite of that, the experiment shows that it is possible to
use the soil as peak load heat source also without
short heap pipes by optimizing the pipe distance and diameter
of the collector.
With the developed analytical and numerical programs it is
possible to simulate extreme situations and design
the collector economical or area oriented optimized,
depending on the clime and the soil properties.
(Wärmepumpen-Info)
EDUAR&D - Multidimensional
evaluation of technology
| Colleague: | Dipl.-Ing. Lutz Dittmann |
| Co-operation: | AGFW, FhG-Institut für Systemtechnik und
Innovationsforschung Karlsruhe, Institut für
Sozialforschung an der Universität Frankfurt, Energiewissenschaftliches Institut der Universität Köln |
| Financing: | BMWA, Arbeitsgemeinschaft Fernwärme e.V. (AGFW) |
| Duration: | 07/05 - 03/2007 |
Abstract
The research project EduarR&D of the Federal Ministry
of Economics and Labour (BMWA) aims at the creation of
efficient tools for the assessment
of activities of federal technology promotion. In this
context the project "Multi-dimensional evaluation of
technology" on the one hand should illustrate
the development direction in the field of production and
storage of heat and electric energy. On the other hand a
sociological approach is followed up
which tries to comprehend and value the decision-making
processes of substantial innovation carriers of this line of
business.
The share of the professorship of energy system engineering
and heat economy of the TU Dresden in the processing
concerns the creation of the base
of the examinations at the technical level. For this purpose
a comprehensive data collection was carried out basing on a
extensive database created
by the project team which takes into account all relevant
technologies at present or in foreseeable future. As a
result a reliable matrix was created
which could be augmented with reflection on the comparative
evaluation of electric energy and heat and on the
consideration of part load condition cases and supply
energies.
The work of the institute of power engineering of the TU
Dresden for this project therewith is completed largely.
Since the processing time period will expand,
however, by delays in the construction of the simulation
models until the middle of 2007, further work will be
carried out to the completion of the database.
Research into optimisation of
interaction of technologies of distributed energy
generation based on fuel gases from renewable energy
sources
| Colleague: | Dr.-Ing. Karin Rühling Dr.-Ing. Bernd Müller Dipl.-Ing. Lutz Dittmann |
| Co-operation: | DBI-Gastechnologisches Institut gGmbH Freiberg
(Netzwerksmanagement) University of Chemistry and Technology Prague, Czech Republic University Miskolc, Hungary Institute of Oil and Gas Krakow, Poland Technische Universität Bergakademie Freiberg Fraunhofer Institut Fertigungstechnik und Angewandte Materialforschung Dresden Institut für Polymerforschung Dresden Institut für Agrartechnik Bornim e.V. Fördergesellschaft Erneuerbare Energien e.V. Berlin MITGAS Mitteldeutsche Gasversorgung GmbH |
| Financing: | BMBF |
| Duration: | 11/03 - 08/06 |
Abstract
The appropriately utilizable reserves of fossil fuels
are restricted. The energy mix of the future depends on an
efficient use of biomass and waste
for supply with electricity, heat and cold. Since 2004 a
network has been operating on the branch of gaseous fuels
which are producible from renewable sources of
energy.
Eleven research institutes and universities of 4 countries
are working together. An analysis of the state of the art
was made regarding the generation
and respectively the extraction of methane-rich gases like
digester gas, sewage gas, landfill gas, mine gas and
hydrogen-rich gas produced by gasification (gasification
gas).
The conditioning of the gas to a quality which allows the
feeding into existing natural gas networks is technically
possible, but it is also associated with high costs.
Alternatively, the material and energetic use was
investigated at locations close to the production of
biomass and waste.
Comparative statements concerning the complete chain from
gas production over necessary refining steps until the use
in CHP-technologies
(gas turbines, gas engines, fuel cells) are focussed. The
new quality is achieved by the consideration of the local
consumption and net structures of heat and cold
supply.
With the ENERGY-database a new tool was created. This tool
allows the comparison of possible process chains depending
on local available resources.
The database can take into account useful solutions either
from the energetic or economic point of view.
The database is enlargeable and can achieve a high degree
of benefit by the continuous update of the data and the
implementation of new algorithms of analysis.
Advanced modelling of losses
in heat storages and development of a calculation method
for an optimised construction design of
storages
| Colleague: | Dipl-Ing. Robert Huhn |
| Co-operation: | FFI in Hannover e.V. |
| Financing: | AiF |
| Duration: | 08/03 - 01/06 |
Abstract
Hot water storage tanks (HWST), integrated in heat or
cold supply systems in an optimal way, contribute to the
reduction of installed capacity,
fuel and operation costs. By smoothing peak loads and
equalising the throughput in pipeline systems they
increase the lifetime of the components.
Furthermore, storage tanks help to reduce return pipe
temperatures and thus energy consumption of circulation
pumps and heat losses in district heating networks
while the power output of combined heat and power
generation (CHP) plants is increased at the same
time.
Already in the AiF-Project 12588 BG key numbers and a test
procedure had been developed for evaluating internal and
external losses of HWST.
This test procedure has now been extended for horizontal
tanks. Experimental investigations were carried out at
Fernwärmeforschungsinstitut in Hannover e.V.,
the research partner of this project.
Internal exergetic losses in HWST are caused by
temperature equalization processes within the tank without
any heat loss to the ambience.
The extension of these losses is influenced by the design
and material properties of the tank as well as operation
parameter like temperature levels and flow rates.
Aim of the examination is to quantitatively and
qualitatively describe these influences. For that reason
dimensionless key numbers have been developed to
deliver
information about tank design and intended operation
conditions.
Comprehensive numerical computations with the CFD-Code
Fluent and experimental tests yielded in empirical
correlations for determination of internal losses in hot
water storage tanks.
An improvement of guidelines for optimized storage tank
design is achieved by coupling the losses to details of
tank design and operation conditions.
Calculation of storage tank losses already during tank
design contributes to cost reductions and reduces tests on
prototype tanks.
The design engineer can easier determine, if a given
storage tank is appropriate for an application with given
boundary conditions, or if the tank needs to be modified
to guarantee an efficient operation.
Thermal disinfection in
central heating installations for drinking
water
| Colleague: | Dr.-Ing. Bernd Müller, Dipl.-Ing. Matthias
Mischke |
| Co-operation: | STS Energietechnik GmbH, TUD- Institut für Medizinische Mikrobiologie und Hygiene |
| Financing: | BMWA, (AiF-ProInno) |
| Duration: | 05/04 - 07/06 |
Abstract
Thermal disinfection in central heating installations
for drinking water
The aim of the project is the development of a prototype
installation for thermal disinfection of DHW by use of
high disinfection temperatures,
reduced reaction volume and of high energy efficiency.
The thermal disinfection of DHW is carried out in
principle like a flow heater.
Due to the short staying time of the water within the
reactor disinfection needs considerably higher
temperatures as usual.
To increase the energy efficiency of the installation
intensive heat recovery between disinfection temperature
and DHW temperature (60 °C) was necessary.
To reduce the required heat energy the application of
compression-type and Peltier-type of heat pumps were
considered.
The heat source of the heat pump is the DHW at a required
temperature of 60 °C as heat sink the disinfection part
at temperatures of about 80 °C is used.
The prototype installation was tested under real
conditions at the Institute for Medical Micro-biology and
Hygiene of the TU Dresden.
The extracellular and intracellular legionellae were
exposed to different disinfection temperatures and
varying time of exposure to determine the inactivation
kinetics.
The inactivation of legionellae occurs within 200 sec. at
a temperature of 65 °C, inactivation time is shortened to
60 sec. at a disinfection temperature of 80 °C.
There is a marginal difference between extracellular and
intracellular legionellae in their in-activation
kinetics.
Intracellular legionellae are marginal more
heat-resistant than extracellular legionellae.
There are comprehensive construction plans and an
instruction manual for the prototype
installation.
Development, construction and
test of a measuring system for determination of steam
moisture
| Colleague: | Dipl.-Ing. Matthias Mischke |
| Co-operation: | Ingenieurbüro Hoffmann, PCE - Ingenieurbüro für Mess-, Steuer- und Regelungstechnik GmbH |
| Financing: | BMWA, (AiF -ProInno) |
| Duration: | 03/05 - 12/2006 |
Abstract
The aim of the project is the development of a
measuring device for continuous measurement of steam
moisture and therefore of the moist steam
enthalpy.
The measuring device shall be compact, offer the highest
possible precision and be insensitive against
fluctuations of the operating parameters.
The built device has to be tested and optimised
extensively at different experimental setups.
After assembly of the device first component tests as
well as examinations of the pressure losses have been
carried out.
They are followed by tests for the determination of heat
losses.
After that the measuring device has been tested up to
now in two different plants.
Migration of heavy
metals from devices of drinking water heating
systems
| Colleague: | Dr.-Ing. Karin Rühling |
| Co-operation: |
Institut für Korrosionsschutz
Dresden GmbH (IKS) |
| Financing: | DVGW, AGFW |
| Duration: | 12/05 - 05/2008 |
Abstract
The new Drinking Water Ordinance is coming into
effect in 2003. Since that time the regulations and
threshold values are available
for cold and hot drinking water similarly. Therefore
the modification of the drinking water quality,
especially the migration of heavy metals,
is important during the path through the domestic
installation and the drinking water heating system
also.
Until today secured technical expertises are only
available for materials and alloys which are certified
via DIN 50931-1 under a cold drinking water
situation.
Comparable awareness for complete devices like
fittings, tap water meters, heat exchangers e.g. are
not available.
There are two main aims of the project. At first the
conception, construction, instal-lation and operation
of a testrig for several kinds of complete
devices
for the assessment of the migration of the heavy metals
cooper, nickel and lead. A comparative study will take
place under cold and hot drinking water
conditions.
At second a comparative field test are carried out in
interaction with housing societies as well as water and
district heating suppliers.
DemoCell – Practical test from
small fuel cells (Projectinfo IMSA)
| Colleague: | Dipl.-Ing. Thomas Pfeifer, Dr.-Ing. Karin Rühling |
| Financing: | DBI Gas- und Umwelttechnik GmbH , NL Freiberg |
| Duration: | 12/01 – 12/06 |