Pioneer Republic Wilhelm Pieck                                                                                                     Publications

Energy, Water Supply and Waste Water Treatment for the Werbellinsee Project
(ex “Pioneer Republic Wilhelm Pieck”)

Harald Kraft* (Ingenieurbüro Kraft)
Schmiljanstraße 7
12161 Berlin, Germany
e-mail: kraft@ib-kraft.de

Andreas Schiller (Ingenieurbüro Schiller)
Rosa-Luxemburg-Straße 28A
14806 Belzig, Germany
e-mail: ingenieure@andreas-schiller.com

Keywords
Decentralized, energy, integrated, rainwater, renewable, re-use, wastewater.

Abstract
In recent years new water management and treatment technologies have been developed and demonstrated in projects. This is true especially for singular concepts using either rainwater management technologies or wastewater treatment in different locations. No experience exists in the operation of integrated decentralised installations including the potential for energy generation. The goal of the research is to gain experience in comprehensive design and implementation of singular technologies aiming at quasi-autark concepts requiring only a minimum of public water, waste and energy management services. Theses concepts should prove to function in different types of settlements and urban structures as well as various regional conditions and demands.

The aim of the research and development component of this project is to demonstrate the functioning of a comprehensive approach under technical, socio-cultural, economic and legal aspects by integrating individual technologies that reflect the state of art. For wastewater management it is proposed to use anaerobic sewage treatment, membrane technology, natural purification procedures as well as faces and urine separating technologies. For water conservation, water saving devices as well as rainwater harvesting and wastewater processing and recycling is envisaged. For solid waste management garbage separation, composting it and incineration is considered.

The recovered nutrients from wastewater treatment and solid waste management shall be used for landscaping horticulture on site and for agriculture in the vicinity of the project site. For the supply of energy, block heating generation plant technology that uses renewable energy resources shall be adopted. The operation and maintenance of all the above installations would be run by one operating authority.

The present situation
The Werbellinsee project (see fig.1), offers place for about 1.100 visitors in around 30 guesthouses. The project was founded by the former German Democratic Republic in 1952 and was named after its founder and the first president of the German Democratic Republic, ”Pioneer Republic Wilhelm Pieck”. Today the project site is used for recreation by the youth (European Meeting Place for Young People), sport, vocational education and international meetings. The area of 200 ha at the marvellous Werbellin lake is covered by 100 ha of forest. The Werbellin lake extends over 10 km in length and 1 km in width.

The project site is located within the Uckermark Biosphere Region. The built up area is protected under the monument protection law and comprises of 42.000 m² floor area. The project was designed by Richard Paulik [1] . At present the heating is provided by a contracting company via a heating network. Waste water is pumped through a 30 km long sewer to a waste water treatment plant. Power and water as well as solid waste management are provided externally by public institutions. The reconstruction of parts of the existing technical infrastructure is planned under the framework of the original autarkic concept of water and energy supply as well as management of solid and liquid wastes.

Aims and objectives
The aim of reconstructing parts of the technical infrastructure is to revive the original autarkic concept of water and energy supply and management.

The research and development project will demonstrate new concepts, technologies and products for minimising wastewater, separation of faeces, urine and water and reusing treated wastewater. Furthermore the potentials of reuse of rainwater can be demonstrated. The decentralised generation of electricity and heat will include the use of organic wastes and leftover wood from logging activities.

The project comprises of the following elements:
1.         Drinking water supply by rehabilitating the existing deep ground water wells on the site,

2.         Minimising wastewater by modern sanitation technologies (separation toilets, dry toilets, separation of urine and faeces, urine will be used for soil improvement)

3.         Remaining wastewater being treated at the treatment plant on the project site (anaerobic treatment of sludge, trickling filter, rootzone treatment and membrane technology) for reuse in irrigation and toilets.

4.         Rainwater run-off collected in cisterns of different dimension for drinking water substitution (baths, toilet flushing, washing machines) and for groundwater recharge.

5.         Anaerobic treatment of organic waste (especially from the restaurants), use of methane gas and sludge from waste water treatment for energy production.

6.         Block heating and power generating plant that produces energy from renewable resources (methane gas, chopped wood, wood pellets)

Wastewater management
Together with the reconstruction of the wastewater treatment plant water saving technologies will be installed. To allow a comparison between different systems the houses will be equipped with different toilet types such as separation toilets and urinals without flushing, Gustavsberg water saving systems, 1 / 2 / 4 litre WC, hybrid toilet systems with water separator connected to a composting facility (for smaller buildings) and Clivus multrum compost toilets.

At the project site a separate sanitary and stormwater drainage system already exists and shall be integrated with the proposed infrastructure. Organic wastes from canteens and faeces separated from sewage will be treated in decentralized methane reactors. The urine will be collected and treated separately and used as fertilizer. The wastewater yield of 1.900 population equivalents will be 285 m³/d and ca. 104.000 m³/a. About 20.000 m³/a of purified wastewater will be used for supplying a nearby moor, thus about 76.000 m³/a will remain for re-use.

Rainwater harvesting
Rainwater run-off from roofs amounting to 13.000 to 25.000 m³/a will be stored in cisterns after being purified. The capacity of the cisterns will vary between 5 to 300 m³ according to the roof areas to be connected. Each cistern will be equipped with a filter, a pumping device and a drinking water connection for top-ups. Water from the rainwater cisterns will be used for drinking water substitution (baths, toilet flushing, washing machines) and for groundwater recharge. The run-off from pedestrian pathways and roads will be between 25.000 and 50.000 m³/a will be collected in infiltration trenches. Rainwater run-off will not be discharged into the Werbellin Lake.

Water supply
The water works at the project site were shut down in 1996. The existing filter tanks will be cleaned, and the pumps, fittings, filter materials (for removing ferric oxide) and backwashing equipment will be renewed.

For irrigation of the intensively used sport fields, for green areas and gardens around 32.000 m³/a in a year with average precipitation and around 60.000 m³/a in a dry year will be needed The total demand of 67.000 m³/a in a wet year can be completely provided for by using purified water from the treatment plant. In a dry year the demand rises to 95.000 m³, hence 13.000 m³ of rainwater and 6.000 m³ drinking water will have to be added to purified waste water.

The demand for process water for toilet flushing is estimated to be 35.000 m³/a. In dry years around 13.000 m³ of drinking water has to be added.

For other purposes (household, small industry) process water from the cisterns is available. In a wet year the demand of around 17.000 m³/a can be supplied in this way. Surpluses will be used for the recharge of groundwater.

Solid waste management
Organic waste from canteens and faeces separated from sewage will be treated in decentralised methane reactors. The compost from toilets together with organic waste from the gardens will be composted and used on site for horticultural purposes. The sludge from the purification plant can be used either for energy generation or for composting in order to close the loop within the project site.

Power generation and heating
Energy has to be supplied for buildings with a total floor area of 42.000 m². At present a demand of about 3.500 kW is estimated for heating purposes.

For a decentralised heating and electricity supply for the project site, a Block Heating and Power Generating Plant (BHGP) will be setup using methane gas from the wastewater purification plant and the methane reactors. The methane gas will be burnt and converted into heat and electricity. For peak demands, chopped wood will be additionally used as a renewable resource for energy production. Wood exists in sufficient amounts in the region. The use of solar energy is not suitable due to the dense tree canopy on the site.

The BGHP technology consists of a boiler which will be heated by a special burner. The hot combustion gas is used to heat thermo-oil in a heat exchanger. By introducing a new technology, the ORC-process, the heat of the thermo-oil is used to support a low temperature steam circulation, which is driving a condensation turbine for generating electricity. The operating medium for the ORC-generator is silicon oil, which has a boiling temperature of 80ºC. This enables a higher degree of efficiency compared to a traditional steam power station. Since the steam generator is heated indirectly, no supervision of the BGHP is necessary and maintenance required for this system is low. Only one person is needed to run the BGHP.

The annual demand for electricity supply is estimated to be 2.000 MWh/a. By installing a block heating and generating plant (BHGP) the energy costs can be reduced by 60%. By using energy conserving techniques of the building renovation, the maximum energy demand for heating will be reduced to 50%. The annual operating time of the BHGP is estimated to be 5.000 hours. This will be sufficient for the generation of 2,500 MWh/a. The electrical output of the BHGP will be 500 kW. Management and regulation of peaks will reduce the power demand peaks to a maximum of 700 kW and contribute to a significant reduction of costs.

Operating authority concept
Operation and maintenance of the installations for energy production and for water and waste management in the project area of Werbellin lake would be run by one operating authority. This can be done by a corporation founded for this particular purpose or by an institution experienced in operating at least parts of the new technology. Whoever shall operate these installations, will have to be trained, as such technologies and their integrated combination do not exist so far in a project of this scale. The local water authority could participate as well. The options of forming an operating authority (corporation) are studied at present.

Conclusions
The aim of the research and development component of this project is to demonstrate the functioning of a comprehensive approach under technical, socio-cultural, economical and legal aspects by integrating new technologies reflecting the state of art. The previously existing autark systems for energy and water supply as well as wastewater treatment will be reactivated and technically modernised. It is expected that the integral planning approach will create a synergy, which will result in the enhancement of both environmental and economic benefits.

		Figure 1: Layout of Werbellinsee Project
Picture in black and white, sharp in contrast (to be  added by Mrs. Bohme)

  Consulting Engineers Kraft - Water resource management                                                                                              imprint