Semicentralized supply and treatment systems
The present settlement development on the East coast of the People's Republic of China is characterized by high population density and enormous population growth. In order to meet the requirements of the rapid population growth, efficient environmental protection and resource management systems have to be established. This is not possible via conventional centralized supply and disposal systems, due to their lacking flexibility. In densely populated areas, decentralized supply and disposal systems also reach their limits, as amongst other things, the hygienic standard can not be guaranteed to the extent necessary. Therefore, in fast-growing urban areas in particular, reliable supply and disposal systems have to found, in form of new integrated systems of a new semicentralized dimension.
In this context, the project includes two main aspects: efficient environmental protection has to be established to minimize hazardous impacts while, at the same time, overexploitation of resources has to be prevented. In order to live up to these principles, the project basically focuses on the recycling of water and material flows. This can only be realized via efficient and integrated system planning in the area of water supply as well as waste and wastewater treatment and disposal.
In this context, the term SEMIZENTRAL stands for dimensions that cover areas considerably larger than single building units, however significantly smaller than conventional centralized supply and disposal systems, serving whole cities of several million people. To implement semicentralized systems, the respective city area is to be divided into smaller supply and disposal sectors, partly with autarkic operation. Thereby, depending on the respective local conditions, these areas should be as large as necessary, but as small as possible.
Thus, the disadvantages of conventional large (centralized) or small (decentralized) systems can be avoided while utilizing their benefits at the same time.
Duration: 12.2003 - 06.2005
Project funding reference number: 02WD0398
The objective of the project is to develop supply and disposal systems that guarantee sustainable resource management. In order to achieve these goals, water and materials (e.g. phosphorus, nitrogen) have to be recycled to a large extent. Therefore, integrated planning of technical facilities for wastewater and waste treatment as well as water supply is indispensable.
Sub-project 2 is the consistent continuation of sub-project 1 and is based on its findings. When realizing the objectives of developing sustainable semicentralized supply and disposal systems, the following aspects are to be kept in mind:
- Reliable supply and disposal systems for fast-growing urban areas in China
- Compliance with required hygienic standards
- Negative impacts on the environment as low as possible
- Application of sustainable processes
- Maximum flexibility and economic efficiency
These goals are to be realized by implementing modular-based supply and disposal systems for water, waste water, and waste that are easily adaptable to the respective local conditions. These systems should combine the technical aspects of the sectors water supply and groundwater protection, wastewater technology, waste management as well as environmental and spatial planning. Thus, technical and organizational synergistic effects are used.
Based on the findings from sub-project 1, one concept was given preference, however, adaption and optimization of its individual technical modules are necessary. One of the objectives of sub-project 2 is to utilize these optimization potentials. Three technical project parts, as described below, will serve this purpose. Another project part will deal with deficits identified during sub-project 1, deficits related to planning, decision and authorization processes as well as possible operating schemes and fee models for the implementation of the developed semicentralized supply and disposal systems in urban areas in China. The mentioned four project parts are as follows:
- Development of an integrated planning, decision and authorization process including operating schemes and fee models (project part A), carried out by the Chair for Spatial and Infrastructure Planning at the IWAR, Technische Universität Darmstadt
- Application of ultrasonic cleaning of membranes in surface water treatment (project part B), carried out by the Chair of Water Supply and Groundwater Protection at the IWAR, Technische Universität Darmstadt
- Production of service water from greywater via compact biological and physico-chemical processes (project part C), carried out by the Chair of Wastewater Technology at the IWAR, Technische Universität Darmstadt
- Production of refuse-derived fuels from municipal waste; production of lactic acid from municipal biowaste as feedstock for the chemical industry (project part D), carried out by the Chair of Waste Management at the IWAR, Technische Universität Darmstadt
Duration: 07.2005 - 07.2008
Project funding reference number: 02WD0607