Papers Delivered at International Conference on Cleaner Production
Beijing, China -- September 2001 -- Paper 12 of 30

The Planning and Design of Eco-Industrial Parks in China 

Ding-jiang CHEN, You-run LI*, Jing-zhu SHEN and Shan-ying HU
Department of Chemical Engineering, Tsinghua University, Beijing, 100084, P.R.China.

Abstract: Projects of Eco-industrial Park (EIP) are initiated in China. In this paper three cases are introduced, which are carried out by the local authorities in corporation with the Industrial Ecology Center in Chemical Engineering Department of Tsinghua University. The projects are Zaozhuang EIP initiative in Shandong Province in North China, with key feature of transforming a traditional industrial zone to eco-industrial park; Quzhou EIP Initiative in Zhejiang Province in East China, with key feature of constructing web of material exchanges among dozens of chemical plants of various sizes; and Nanhai EIP initiative in Guangdong Province in South China, with key feature of developing environmental protection industry in a greenfield. The planning work focuses on identifying potential by-product exchanges, exploring possible water/energy cascading usage, modeling industrial symbiosis system, and developing EIP management information system.

Keywords: Eco-Industrial Park, China

1. Introduction 

Eco-Industrial Park (EIP) is an industrial system of planned materials and energy exchanges that seeks to minimize energy and raw materials use, minimize waste, and build sustainable economic, ecological and social relationships [1]. A number of EIP initiatives are emerging in recent years and undergoing a fast development in many countries [2].

China has experienced a rapid economic growth in the last twenty years. Now the country is facing a series of resource and environment issues, which have blocked the economy's healthy development. As an effective economy and environment win-win strategy, the EIP concept has begun to be serious in consideration by authorities and communities in some industrial regions in China. Several EIP projects are initiated by local authorities, which are in cooperation with academic institutions.

The Industrial Ecology Center in Chemical Engineering Department of Tsinghua University is active in the area of EIP research. The members of the center have taken part in three EIP initiatives in China since 1999. The projects are Zaozhuang EIP initiative in Shandong Province in North China, with key feature of transforming a traditional industrial zone to eco-industrial park; Quzhou EIP Initiative in Zhejiang Province in East China, with key feature of constructing web of material exchanges among dozens of chemical plants of various sizes; and Nanhai EIP initiative in Guangdong Province in South China, with key feature of developing environmental protection industry in a greenfield.

2. Zaozhuang EIP Initiative 

Zaozhuang Industrial Park consists of 150 hectares of land, where more than ten enterprises are currently located in. Anchor members include a coal based ammonia plant, a heat and power station and a cement mill. Other members are a carpet mill, a coke factory, a ceramic factory, a carbide factory, etc. A wastewater treatment plant and a residential area are located in the park's vicinity.

Very few material linkages have existed among the members. Almost all the plants have their own boiler system which by-produce waste cinder and fly ash. They supply the solid wastes to the cement mill as raw material. The power station provides heat to the residential area in winter. The coke factory once tried supplying coke-oven gas to the ceramic factory as fuel for roasting ceramic products, but failed for technical reason.

Potential linkages based on the existed linkages are needed for transforming the park from a traditional pattern to an eco-industrial one. After analyzing the input and output of the members and consulting references for technical feasibility, several potential linkages are identified as showed in Fig.1. The wastewater treatment plant can provide treated water to power station and ammonia plant to satisfy the large demand for cooling water, and at the same time, to save the scarce local water resource. The power station can supply process steam to other members for shutting down the inefficiency small steam boilers, for which new investment is needed to rebuild the old steam supply system. The carbide factory can supply its slag to the power station to substitute part of the limestone for desulphurization purpose. And gypsum, the product of desulphurization process, can be supplied to the cement mill as part of raw material.

Figure 1 - Zaozhuang EIP Initiative

Recruitments are also considered. A new unit of CO2 gas fertilizer may helpful for utilizing the wasted CO2 gas release by the ammonia plant. The CO2 gas can also be supplied to a new unit in the carbide factory. With the gas and the carbide slag, the unit can produces light calcium carbonate as building material. The wasted hydrogen of the ammonia plant can be used to produce peroxide if a peroxide unit is built. Enrollment of a brick mill may consume the large amount of cinder and fly ash accumulated in the past of the power station.

The design and management of EIP should be conducted based on quantitative analysis, for which a model for EIP optimal decision is developed with an object oriented method [3]. The model consists of two kinds of blocks: member models and connection models. These blocks form a modular architecture. Logical proposition expressions are introduced into the model to express EIP scenarios with different topological structure, so that which can be formulated as a mixed integer nonlinear programming (MINLP) problem. It is easy to expand, modify, and reuse the model. Three mass and energy integrated scenarios of Zaozhuang EIP are studied by applying the developed model. The study results provided us rich information, such as the optimal structure of the EIP, flow rate of material flows, profit of each facility, etc. We can use the model to coordinate the exchange activities among members and to help deciding whether the new units should be established and what are the suitable capacities.

Our study shows that, comparing with the traditional form, Zaozhuang EIP is estimated to achieve reduction in water consumption by about 40%, sulfur dioxide discharge by about 17%, and carbon dioxide emissions by about 13%, respectively.

3. Quzhou EIP Initiative 

Quzhou EIP is a cluster of dozens of chemical plants of various sizes, which are located in Quzhou City, west of Zhejiang provinces. A disadvantage of the park is that it is in the upstream area of Qiantang River, the primary water resource of the whole Zhejiang province. The industrial pollutions, mainly water pollution, lead to great environmental pressures by the public and government, which force the park has to find a solution to upgrade both economic and environmental performances. The EIP planning project for Quzhou is of great significance for local authority and communities.

Figure 2 - Demonstration of industrial food web in Quzhou EIP

A demonstration of the industrial food web in Quzhou EIP is showed in Fig.2. The core of the park is Juhua Group, one of China's 18 largest chemical industrial enterprises. It covers an area of over 600 hectares of land. Three pillar industries of the group are fluorochemical industry, chlorine and soda chemical industry and chemical processing of coal. At present the group has over 30 plants, branches, 46 sets main production systems, and complete infrastructures. It produces over 180 varieties of products, including basic chemical raw materials, chemical medicines, chemical ores, nonferrous metals, construction materials, etc.

A material exchange network has been created within the core. Several processes are well designed for co-producing as showed in Fig.3. By-product HCl of freon unit is fed to PVC unit replace part of the fresh HCl, which remarkably reduces the cost of producing PVC and makes the traditional high-cost carbine-ethyne-PVC reaction path more competitive. A poly-generation scheme for methanol and ammonia has great market flexibility and can reduce emission of byproduct CO2.

Dozens of companies related to the Juhua Group can be divided into three types. Type A companies provide raw materials and auxiliary materials to the core. Type B companies utilize chemical products of the core for further processing. Type C companies consume wastes mainly from the core. Juhua Group produces about 0.8 million tons of solid wastes annually, mainly cinder, fly ash and chemical solid wastes, over 80? of which are fed to cement mills and bricks mills located in Quzhou. The group also produced 23 thousand tons of liquid wastes annually, over 70? of which are feed to the around small companies for recycle and reuse. For example, the wasted H2SO4 are used to produce phosphoric fertilizer; the wasted CCl4 of freon unit are recycled as solvent by distillation; the wasted oil of nylon unit are used as fuel.

We've developed a Management Information System (MIS) for Quzhou EIP, which assists the EIP members to gather and distribute information, identify opportunities for waste exchange and strengthen the environment management. The MIS is based on the prevalent Browser/Server architecture. Users can access the system via the Internet, with regardless of time and location. Data highly concerned with EIP are carefully collected and organized, including survey of members, detail input and output, environmental monitoring data, environmental criterion, etc. All the data can be easily queried, modified and statistically operated by users with appropriate authority.

We've also developed a module aiding the EIP management committee in evaluating potential member for recruitment, which is integrated with the EIP MIS. The module applies fuzzy math technology, considering aspects of economy, resource, environment and job creation, which can give the committee users a quantitative result. By applying the module, the decision-makers can make better choices in recruitment process than ever which mainly depend on experiences and subjective judgments.

4. Nanhai EIP Initiative 

Nanhai EIP is a greenfield site focusing on environmental protection industry (EPI), which has a largely potential market and is becoming a key development field in China. We plan to develop the park as one, which has co-located green businesses within the park that implement eco-industrial principles and at the same time combine with virtual business networks outside the park.

Four types of environmental businesses are preferable to others:

1. Businesses of environmental equipment manufacturing, such as sewage treatment equipment, garbage treatment equipment, desulfurization and denitration equipment, automated environmental monitoring instrument, etc.
2. Businesses of environment friendly products, such as biodegradable plastic, green dope, green refrigerating medium, etc.
3. Businesses of environmental protection research and service, such as environmental academic institution, environmental engineering company, environmental education center, etc.
4. Businesses of wastes recycle, reuse and regeneration, such as producing liquid fuels from waste plastic, wastewater regeneration, solvent recycle, etc.

Members of the EIP may benefit from five aspects:

1. Material integration, including wastes recycle and treatment center, byproduct/waste exchanges.
2. Water integration, including wastewater reduction by cascading usage, recovering valuable material from wastewater, and central wastewater treatment.
3. Energy integration, including central heating system, energy cascading usage, energy saving technologies (heat pump), cleaner energy usage (solar energy, renewable bio energy are under consideration).
4. Information integration, including web capability EIP Management Information System, environmental management and technology service.
5. Harmoniousness with the local environment, including maintaining local nature ecosystem, park landscape design, green buildings.

As the Nanhai EIP is a complete new one, there are much more uncertainty but at the same time flexibility. More efforts are needed in recruitment of new businesses, finding sources of financing and improving the eco-industrial plan of the park.

5. Conclusion 

The EIP initiatives mentioned in this paper will continue their development and be good patterns of other regions in China, especially the west regions where are rich in resource but low in economic growth. Big investment in end-of-pipe control technologies should be skipped, and jump on the economy and environment win-win strategic bandwagon. Eco-Industrial Parks is likely to have a growing development in the coming years in China.

Reference 

[1] Eco-Industrial Park Workshop Proceedings [held October 17-18, 1996], February 1997.

[2] Li Y. R., Shen J. Z., Hu S. Y., Chen D. J.. Study and Progress On Industrial Ecology and Eco-industrial Parks. Journal of chemical Industry and engineering (China). 2001, v52(3):189-192.

[3] Chen D. J., Li Y.R., Shen J.Z., Hu S. Y.. Decision Support System and Kernel MINLP Model for Eco-Industrial Park. The First Joint China/Japan Chemical Engineering Symposium, Beijing, 2000.

* corresponding author

email: liyr@mail.tsinghua.edu.cn