Novel Evaluation Method for Cleaner Production Audit in Industrial Parks: Case of a Park in Central China
1. Introduction
The ‘Paris Agreement’ was adopted as a new climate agreement during the 21st Conference of the Parties (COP 21) at the United Nations Framework Convention on Climate Change (UNFCCC), held in Paris, France. The main objective of the Paris Agreement is to limit the global average temperature increase to well below 2 degrees Celsius above pre-industrial levels [1]. To achieve this goal, all countries are required to contribute by reducing their greenhouse gas emissions. Therefore, during the ‘14th Five-Year Plan’, China’s ecological civilization construction entered a critical period focusing on carbon reduction, realizing the improvement of ecological environment quality from quantitative change to qualitative aspects. At this new stage of development, the industrial sector remains a material pillar of China’s economic and social development. However, the industrial sector is a major source of energy, emitting large amounts of greenhouse gases and pollutants. Industrial energy consumption accounts for more than 65% of the country’s total energy consumption and emits more than 80% of the country’s carbon dioxide and more than 75% of atmospheric pollutants such as sulfur dioxide and particulate matter [2].Therefore, green and low-carbon transformation in the industrial field is key to the implementation of the Paris Agreement’s carbon reduction commitments and is also a significant way for China to achieve peak carbon, carbon neutrality, and the in-depth implementation of pollution prevention and control.
As the most effective means of promoting cleaner production (CP), a cleaner production audit allows enterprises to achieve energy savings, consumption reduction, emission reduction, and efficacy enhancement [3]. Cleaner production has been explored and practiced for more than 30 years. The research principally focuses on the enterprise and industry level, including the summary and evaluation of cleaner production technology, and the construction and evaluation of a cleaner production index system [4,5,6,7]. In recent years, the key enterprises, as the primary bodies conducting cleaner production audits, have achieved remarkable results; the number of participating enterprises has increased significantly, and the pollutant emission intensity has been decidedly reduced [8]. However, compared to the base of tens of millions of enterprises in China, the proportion of enterprises implementing cleaner production audits is low, and the promotion of green and low-carbon development in China’s industrial field is still very limited. According to statistics, as of April 2022, there are 2773 national and provincial industrial parks, including 663 national industrial parks and 2110 provincial industrial parks, and nearly 200,000 enterprises have settled in national and provincial industrial parks [9,10,11]. In contrast, industrial parks, as organizations of enterprise agglomeration, have significant advantages in expanding the scope of cleaner production audits and improving audit results [12].
The early research chiefly considered the cleaner production audit of enterprises in the park and promoted the ecological improvement of the park by improving the cleaner production level of the audited enterprises. Later, with the continuous innovation of the cleaner production audit mode of industrial parks in the national policy, more research broke through the original audit ideas and further expanded the audit implementation object and application scope to the industrial park level. For example, Liu Xiaoyu [9] et al. summarized the problems and suggestions for promoting cleaner production audits in industrial parks in China. Wei Yao et al. combined enterprise audits with park audits and proposed measures such as building an ecological chain, improving facilities, and optimizing cleaner production programs to promote cleaner production in industrial parks [13]. Liu, Zheng proposed the framework for promoting cleaner production in industrial parks under the new situation of environmental protection and put forward specific implementation plans from three perspectives: macro, medium, and micro, from the perspective of environmental elements [14]. At present, only Guangdong Province has promulgated the cleaner production index system for electroplating industrial parks in Guangdong Province. This index system is only for electroplating industrial parks and does not have universality. Environmental management in developed countries has been mostly carried out from the life cycle perspective, such as the European Union’s Waste Framework Directive. While in China, environmental management is more concerned with the production process, such as the CP audit system [15]. But the unformed audit methodology and the lack of effective practical exploration experience have hindered the development of cleaner production in industrial parks [16]. In this study, the evaluation index system of cleaner production audit in industrial parks, including carbon accounting indicators, was established. The binary semantic method was used to establish a cleaner production audit model for industrial parks. Case studies were carried out to optimize the industrial structure of industrial parks and the construction of ecological industrial chains. The hope is to provide a theoretical basis for the development of cleaner production in industrial parks, promote the sustainable development of industry, and achieve the goals of reducing pollution and carbon reduction.
The innovations of this study are reflected in the following aspects: (a) A set of industrial park cleaner production index systems was integrated through the comparison and analysis of existing indicator systems. (b) Indicators related to carbon emissions were considered in order to achieve the goal of carbon neutrality. (c) The two-tuple linguistic evaluation method was applied to the establishment of the rating model. (d) A case study of a cleaner production audit in industrial parks was performed to evaluate the overall cleaner production level of industrial parks and to build ecological cycle chains for it.
4. Case Study
4.1. Basic Situation of Industrial Park
4.1.1. Research on the Current Situation of Industrial Park
This study selected a park in central China (referred to as industrial park G) for the case analysis. The current value of the quantitative indicators was obtained through field research in industrial park G. A summary of these result is presented in Table 1.
The survey results of the quantitative indicators of industrial park G are as follows:
(1) The industrial policy compliance of X44 Industrial Park: It meets the requirements of national industrial policies such as the ‘Industrial Structure Adjustment Guidance Directory (2019 Edition)’, ‘Industrial Transfer Guidance Directory (2012 Edition)’, ‘Foreign Investment Industry Guidance Directory (2017 Revision)’, ‘Environmental Protection Comprehensive Directory (2017 Edition)’, and ‘Negative List of Market Access (2018)’.
(2) X54 Industrial Park waste gas treatment facilities: According to the survey, the production process of some enterprises in industrial park G is accompanied by VOCs, but the VOC treatment facilities are not perfect; some enterprises involved in the unorganized emission of pellets have no corresponding collection and treatment facilities; the storage and transportation of solid waste in some enterprises are not strictly in accordance with the relevant regulations.
(3) Transformation of coal-fired boilers in X55 Industrial Park: According to the survey, industrial park G completed the elimination of small coal-fired boilers and the clean energy transformation of coal-fired boilers in the area by the end of 2016, and all coal-fired boilers below 10 steam tons have been eliminated.
(4) Central heating in X56 Park: Central heating facilities are under construction, and central heating has not yet been realized.
(5) X62 Park pollutant discharge standard: The major air and water pollutant emissions did not exceed the total amount and concentration control index, and all types of solid waste were properly disposed of.
(6) Implementation of environmental laws and regulations in X63 Industrial Park: The new renovation and expansion projects of industrial park G strictly implement an environmental impact assessment system with an implementation rate of 100%. Simultaneously, the ‘three simultaneous’ system is strictly implemented. The status quo is in line with national industrial policy. Processes, equipment, and construction projects use coal and heavy oil as fuel.
(7) X64 Park environmental monitoring system: At present, the routine monitoring of environmental quality in industrial park G relies on local environmental protection departments.
4.1.2. Industrial Park Index Status Value
Based on the previous research on industrial park G, the current values of each index were calculated according to the description requirements of the index. The results are shown in Table 2.
4.2. Evaluation of Cleaner Production Level in Industrial Park
(1) Non-dimensionalities of indicators
To determine the membership matrix of an index, its properties must first be divided. According to the characteristics of this index system, the indicators were divided into quantitative, quantitative, and qualitative. This classification is illustrated in Figure 4. The yellow plate is the quantitative reverse index, the green plate is the quantitative positive index, and the blue is the stationarity index.
(2) One-level fuzzy operation
According to Table 2, and can be calculated, respectively, and are expressed below in the form of a matrix. Because the park does not involve the utilization of waste heat and pressure, the weight value of the utilization rate of waste heat and pressure in X33 Park is transferred to other indicators.
According to Equation (6), the membership degree of criterion layer X1 with respect to Sk = (S1, S2, S3) can be calculated as follows:
The membership vectors of X1 with respect to Sk = (S1, S2, S3) are T11 = (0.3657, 0.2138, 0.4205).
Similarly, T12 = (0.5367, 0.4633, 0.0000), T13 = (0.2475, 0.7525, 0.0000), T14 = (0.0811, 0.5475, 0.3714), T15 = (0.3984, 0.2220, 0.3796), and T16 = (0.3725, 0.5315, 0.0960) can be calculated. The second-level fuzzy judgment matrix T1 of the industrial park is obtained in the Supplementary Materials.
(3) Two-level fuzzy operation
According to Equation (7), the second-level fuzzy operation is performed, and the cleaner production grade membership degree S1i of the park with respect to the target layer Sk = (S1, S2, S3) can be obtained.
S11 = 0.3524; S12 = 0.4036; S13 = 0.2440.
4.3. Analysis and Suggestions for the Evaluation Results of Industrial Park G
4.3.1. Evaluation Results of Industrial Park G
The two-tuple semantic group of the target layer of industrial park G is , It is determined that the industrial park belongs to the S2 level and is identified as a cleaner production park. The deviation value shows that the cleaner production level of industrial park G is better than the lowest level of the S2 level, but there is still clean production potential that can be tapped. Figure 5 shows the membership degrees of the six first-level indicators of Sk. The greater the proportion of X index Sk in the figure, the closer the status of this index in the industrial park is to the level. It can be seen from the graph analysis that the X2 resource and energy consumption index and the X3 resource comprehensive utilization index of industrial parks have the highest contribution to the evaluation results, and both the X1 pollutant emissions and the X4 industrial cleanliness indexes have great clean production potential. The low contribution of the X1 index to the evaluation results is primarily due to the poor control effect of volatile organic compounds and carbon emissions. Most of the enterprises involved in volatile organic compound (VOC) emissions in the park have not set up VOC collection and treatment facilities. However, sulfur dioxide, ammonia nitrogen, and particulate matter emissions had better control effects. In terms of wastewater pollutants, the total amount of wastewater was well controlled, but the leading enterprises in the park included food and beverage processing, textiles and garments, wood processing, and furniture manufacturing, resulting in a large amount of chemical oxygen demand and ammonia nitrogen. In terms of X4 industrial cleanliness indicators, the output value of machinery manufacturing, electronic manufacturing, food and beverage processing, textiles and garments, wood processing, and furniture manufacturing dominate the park, accounting for more than 80%. The industrial concentration is high, a good industrial chain has not been formed, and the industrial correlation degree is low.
4.3.2. Cleaner Production Recommendations
(1) Improvement in VOC collection and treatment facilities.
As one of the key air pollution indicators during the 14th Five-Year Plan, it is particularly important to control the generation and emission of VOCs at the park level. According to the survey, industrial park G is primarily focused on machinery manufacturing, electronics manufacturing, food and beverage processing, textiles and garments, wood processing, and furniture manufacturing, as well as a small number of chemical raw material manufacturing, printing, and building material enterprises. Although there are a few waste-gas-polluting enterprises, most of the enterprises involved in VOC emissions in the park have not set up VOC collection and treatment facilities, resulting in VOC emissions per industrial unit added value of the park reaching 1.9838 kg/10,000 yuan. Therefore, parks should focus on the control of VOCs, do a good job in VOC collection and treatment, encourage enterprises to use low-VOC raw materials, and further control their generation from the source.
(2) Reducing carbon emissions from parks
Currently, the carbon emissions from industrial park G are relatively high. Currently, energy consumption is the major source of carbon emissions from parks. In the future development process, parks can promote waste incineration capacity and cogeneration technology upgrades, which will have significant emission reduction potential and synergistic environmental and economic benefits. Simultaneously, attention should be paid to the elimination of high-energy-consuming equipment in enterprises within the park, and the carbon emission reduction task within the park should be completed by eliminating or replacing backward production capacity and improving energy efficiency, waste heat recovery, and utilization [37,38].
4.3.3. Industrial Park Green Low Carbon Cycle Development Plan
Within the park, the stakeholders include government departments, infrastructure, and manufacturing and service industries. Infrastructure and manufacturing are the primary components of most parks and are also the focus of current park carbon emissions. A complex material and energy flow network exists among the enterprises in the park [39]. The upstream and downstream supply chains among enterprises, industrial clusters composed of the same enterprises in the industrial sector, and recycling industry symbiosis formed among some enterprises to reduce waste constitute the material and energy exchange model of the park, which further increases the complexity of carbon emissions accounting in the park. Figure 6 shows the possible modes of energy and material exchange within the park. With the continuous deepening of the industrial integration development of the park, to realize the low-carbon development of the park, in addition to strengthening the relationship among the major bodies of activities and establishing a solid triangular relationship, we must also tap the potential of the material and energy flow networks between enterprises. By maintaining and strengthening the balance of the ecosystem of the industrial park, it can realize the efficient recycling of resources and energy, reduce waste emissions, and achieve harmony, economic efficiency, and a virtuous ecological circle.
Cleaner production only involves material and energy flow analyses within an enterprise, which is not conducive to material recycling. The construction of the industrial chain considers recycled materials as the major body, processes as the means, and equipment as the carrier, and has gradually become core of the integration of industrial park development. To improve the level of cleaner production in industrial parks and enterprises in development zones, combined with the nature of the mainstream enterprises in the park and data from enterprises in the development zone, 16 representative enterprises with clean production potential in the park were selected to build the ecological chain of the park, as shown in Figure 7. Q stands for different enterprises in the industrial park. The green lines, blue lines, and red lines in Figure 7 denote the transport pathways of particulate matter, liquid substances, and gaseous compounds within the industrial park. This visualization helps to analyze and manage the environmental impacts associated with industrial activities in the park.
The enterprises in industrial park G are primarily machinery manufacturing, electronic manufacturing, food and beverage processing, textiles and garments, wood processing, and furniture manufacturing, accounting for more than 80%, and the industry is concentrated downstream of the industrial chain. During the construction of the industrial chain, the material flow chain was found to be relatively singular, and the sustainable development of the park was inadequate. In the later construction of the park, chemical raw material enterprises, polyester processing enterprises, and other enterprises could be introduced to ‘supplement’ the existing industrial and material chain of the industrial park. Simultaneously, the park can also introduce hazardous waste treatment enterprises to conduct the centralized management, recovery, and treatment of hazardous waste generated by enterprises within the park. This can not only reduce the environmental risk of hazardous waste storage, but also reduce the energy consumption for the long-distance transportation of hazardous waste. It also aids in building a symbiotic, systematic, and circular enterprise network in the park to maximize the utilization of resources, improve the level of cleaner production in the park, and build a sustainable park.
5. Discussion
This study establishes an industrial park cleaner production index system and evaluation model based on the background of peak carbon and carbon neutralization. Although the cleaner production index system of industrial parks does not contain complete carbon-trading system indicators and does not explore the relationship between greenhouse gas management and emission trading from quantitative or qualitative perspectives [40], the carbon emission indicators of the industrial parks covered need the parks to account for their own carbon emissions, which helps to promote the establishment and improvement of the carbon-trading system in the industrial field. The application of the established index system and evaluation model has verified its feasibility in practice. However, it must be admitted that the proposed model and index system may have limitations and incompleteness, for example, regarding how to promote the local consumption of renewable energy from the perspective of index construction [16], how to realize the deep low-carbonization of industrial parks, and how to conduct the model energy-based analysis of time series carbon emissions data at the park level [41], etc., all of which require more in-depth research and more case practice. If this study is fortunate enough to be published, then we hope that this method can be adopted by more industrial parks and provide insight.
In addition, when Chinese enterprises conduct cleaner audits, the last and most important stage deals with sustainable cleaner production. It includes the formulation of long-term pollution reduction and consumption reduction targets and the promotion of sustainability education for enterprise employees. The concept and measures of cleaner production are of great significance to promote the sustainable development of enterprises and industrial parks [42]. From the industrial level, the promotion of sustainable education can achieve wider and faster dissemination. At the same time, it can also promote the construction of ecological parks and cleaner production parks. Therefore, when promoting cleaner production at the industrial park level, more attention should be paid to sustainable education, incorporating it into the audit process.
6. Conclusions
Based on an extensive study of laws and regulations issued in recent years and the available literature, this study proposes a set of cleaner production index systems for industrial parks, establishes an evaluation model based on a binary semantic evaluation method, and applies it to industrial park G, which can provide theoretical support for the country to promote regional collaborative audits.
The conclusions can be summarized as follows:
(1) Summarizing the evaluation index system of cleaner production in the industry, the relevant evaluation standards of various parks, and the research results of scholars, the relevant indicators of cleaner production in industrial parks were screened. A cleaner production index system for industrial parks with 3 levels, 6 criteria, and 35 indicators was constructed.
(2) A fuzzy mathematics evaluation model of cleaner production based on the two-tuple linguistic evaluation method was constructed. The establishment of the evaluation model has realized the innovation of a cleaner production audit method system, and accelerated the formation of cleaner production technology methods and evaluation rules in industrial parks.
(3) Through empirical research on industrial park G, this study analyzes the potential for cleaner production in the industrial park, proposes suggestions for cleaner production, builds an ecological chain, and drafts reasonable suggestions for the future planning of the park to promote ecological priority, and the economical and intensive green and sustainable low-carbon development of industrial parks.
This study aims to shatter the traditional cleaner production audit mode, breach the limitations of a single enterprise as the audit object, satisfy the practical needs of quickly and effectively improving the overall cleaner production level of the park, effectively support the key industries and key areas to reduce pollution and carbon reduction by industrial upgrading, and promote the sustainable development of the industry.
