پارک های سازگار با محیط زیست صنعتی: محرک توسعه پایدار در پارک های صنعتی مختلط

In several industrialised countries, there have occurred initiatives to establish eco-industrial parks. Originally, these were mainly based upon the exchange of resources between heavy industries in industrial complexes. These initiatives are generally referred to with the concepts of industrial symbiosis and eco-industrial parks. Since then, the concept of eco-industrial parks has been extended to another relevant type of industrial park, the so-called mixed industrial park, which consists of various small- and medium-sized enterprises (SMEs), sometimes complemented by a small number of larger industries. Because of the resulting growing ambiguity in the significance of eco-industrial park initiatives, a typology is desirable for entangling the confusion that is introduced. It is argued that mixed industrial parks are poorly investigated although they have a major environmental and spatial impact. Starting from a general consideration of eco-industrial park initiatives, this paper describes the societal and environmental problems that are related to the mixed industrial parks, proposes solutions and discusses the counteracting factors. While our argument relates strongly to the traditionally industrialised countries, it is also relevant to newly industrialised countries, as they are faced with similar problems, or will encounter them in the near future.

In the Netherlands, as well as in the United States and Canada, the discussion on eco-industrial parks has explicitly started since about 1995. Many elements in this discussion are related to subjects that have been considered earlier separately, such as ageing, country planning, utility production, and waste handling. One of the roots of this discussion is in the concept of industrial ecology, which in turn was an attempt to face the problems that were related to resource consumption, waste production, and emission, by an integrated approach. In developing this concept, the challenge for sustainable development played a significant role. The need for unleashing the economic progress from the consumption of finite resources and from the discharge of waste is crucial to sustainability. To obtain this, measures were advocated that combine economical and ecological advantages. Although the basic ideas of industrial ecology were already discussed in papers of the mid-1950s, which have been reviewed by Erkman (1997), the first paper that explicitly formulated the principles of such an approach and that brought these ideas to a broader audience was by Frosch and Gallopoulos (1989). Industrial ecology intends to transform the industrial system by learning from the functioning of the natural environment. In the natural system, all components are integrated and no waste is produced. It needs a systematic analysis of materials flows inside the so-called technosystem, which includes the human-controlled production and consumption processes and which is positioned against the ecosystem. The basic characteristics of industrial ecology are formulated as follows ( Erkman, 1997): 1. It is a systematic, comprehensive, integrated view of all the components of the industrial economy and their relations with the biosphere. 2. It emphasises the biological substratum of human activities, i.e. the complex patterns of material flows within and outside the industrial system, in contrast with current approaches, which mostly consider the economy in terms of abstract monetary units, or alternatively energy flows. 3. It considers technological dynamics, i.e. the long-term evolution (technological trajectories) of clusters of key technologies as a crucial (but not exclusive) element for the transition from the actual unsustainable industrial system to a viable industrial ecosystem. This innovative approach has been frequently used by both investigators and industries for making inventories of material flows inside the technosystem and for optimising the material flows with respect to the environmental and economic performance of production processes and enterprises. It has also given theoretical background to the current tendency towards “closing the chain”. Although complete closing of the chain of materials flows in the technosystem is utopian, the waste reduction might be considerable and will result, e.g. in closure of landfills in Germany not later then the year 2020. However, the discharge of some dilute emissions such as carbon dioxide, and the creation of small amounts of high-risk wastes that have to be stored in a controlled way, are unavoidable for the time being. Regulation has resulted in bans and restrictions on waste disposal and the costs that are related to waste processing are increasing. This has been a strong incentive for the coming of age of a formerly somewhat obscure, but presently a well-established and innovative branch of industrial activity: the recycling industry. Based on the framework of industrial ecology, the concept of industrial symbiosis emerged. This concept was introduced by Lowe and Evans (1995), based on studies on spontaneously emerged industrial complexes in which the different industries exchanged material flows on a large scale: Houston Ship Channel in Texas, and Kalundborg in Denmark. In the USA, a prestigious project was initiated by the Environmental Protection Agency of the Federal Government. This was called the eco-industrial park project. In this project under responsibility of the President's Council on Sustainable Development (PCSD), experiences should be gathered by co-operating universities, consultants, project developers, local authorities, etc. and dispersed on interested parties for establishing eco-industrial parks. In a 1996 workshop, information was exchanged on 15 sites in the USA and Canada (PCSD, 1997). In this workshop, the definition for the term eco-industrial park was established. Two definitions were selected, the one focusing on societal performance, the other on technical performance: 1. A community of businesses that collaborate with each other and with the local community to efficiently share resources (information, materials, water, energy, infrastructure and natural habitat), leading to economic gains, gains in environmental quality, and equitable enhancement of human resources for the business and local community. 2. An industrial system of planned materials and energy exchanges that seeks to minimise energy and raw materials use, minimise waste, and build sustainable economic, ecological and social relationships. Although these definitions largely coincide, there are differences, as the second one has an explicit emphasis on physical flows (materials and energy), while the first definition focuses on organisational and societal processes. In this paper, we will explain that this distinction is not accidental, but rather reflects the different problems that arise in different kinds of industrial parks. The focus on materials and energy exchange has its roots in the chemical industries. This principally refers to “classical” industrial complexes that consist of concentrations of materials and energy intensive, so-called heavy industries which intrinsically are mutually interrelated. These complexes can be situated close to each other, but they are often in a zone, for instance alongside a waterway or close to an ore deposit. The other approach is principally inspired by the problems related to mixed industrial parks, which usually house a variety of small- and medium-sized enterprises (SMEs). The challenges there are indeed far more diverse and not confined to the exchange of the many relatively small and diverse flows of materials and energy. Additionally, we will discuss examples of both approaches, and we will stress that the appropriate planning and management of mixed industrial parks will become an urgent problem in the near future. Although many examples are taken from the Netherlands, which is indeed a densely populated and highly industrialised country, the associated problems are characteristic to the industrialised world and are emerging in newly industrialised countries as well.

In this paper, a study on the different aspects of the establishment of eco-industrial parks has been elaborated. For a better orientation in this complicated field, a scheme for the classification of these projects has been proposed. Two major types of industrial park have been distinguished: industrial complexes and mixed industrial parks. In industrial complexes, the exchange of materials and energy flows has always been essential, but incentives towards a further extension of this integration to lower-grade residuals often failed in the implementation stage because of mainly economic reasons. The most profitable opportunities were already implemented since long and incentives with marginal profitability or moderately high risk were canceled, although a considerable reduction in CO2-emission could be obtained by them. Moreover, the dynamics of the involved industries, including closures and moves, frequently interfered with the long lead-time of the projects. In the literature, the impact of mixed industrial parks, although increasingly important from both an economic and an ecological point of view, has been underestimated to a great extent. This became evident by the nearly exclusive emphasis in the literature on the Kalundborg example as the model for eco-industrial parks. Divergence in the interests of the involved enterprises, poor organisation, and a lack of acquaintance with co-operation have been identified as the principal causes for the slowing down or failing of most of the initiatives. The following opportunities, although often neglected in the literature, have been identified: (1) the presence of specialised enterprises, notably on waste collection, waste processing, and recycling; and (2) the possibility of clustering of comparable small enterprises. Because mixed industrial parks tend to drastically replace the agricultural occupation of area in densely populated, industrialised or industrialising regions, the accompanying problems that arise should be consciously faced with. This requires the establishment of a policy that meets the interests of all involved parties, also on the medium and long term, inclusive the problems of adaptation to changing circumstances, and ageing. This policy should be based on ample quantitative data that are, however, only poorly available. Case studies reveal that although the desires of the enterprises and the authorities with respect to sustainability are clear, the implementation of concrete measures proceeds slowly and has only a marginal effect. The diversity of interests of the different stakeholders, and the obviousness in claiming new industrial area because of modest ground prices counteracts the indispensable restructuring of existing parks as well as a stricter regulation in both existing and new parks. In the discussion on eco-industrial parks, it is advised to pay more attention to mixed industrial parks, and to find and implement solutions that ensure both the continuity and the sustainability of these parks.