Research on the recycling decision of WEEE in rural China under dual supervision

Abstract

Against the backdrop of promoting green, low-carbon, and high-quality development, this paper aims to promote efficient recycling of waste electrical and electronic equipment (WEEE) in rural China. In this paper, considering the integrated development of urban and rural areas and the standardization of industrial recycling system, under the joint action of the extension of producer responsibility and “dual regulation” of supply and marketing cooperatives, the evolutionary game model and system dynamics model of three-level recycling network of farmers, supply and marketing cooperatives and retailers are established. The mechanism of the participants to promote the recycling of WEEE in rural areas is discussed and the strategic choices and interactive relationships of various entities in the evolutionary process were used to analyze through the evolutionary game method. Meanwhile, using the theory of system dynamics, the main influencing factors of different evolution stages and the dynamic change process of the system are analyzed. The results show that: (1) supply and marketing cooperatives, retailers, and farmers can initially tend to participate in and supervise the recycling of WEEE; however, (2) they can finally achieve strong supervision, actively undertake and participate in the recycling and stabilization stable strategy of rural WEEE depends on their benefits and cost of expenditure expenditures are reasonable. (3) The strategic choice of supply and marketing cooperatives has the most significant impact on the strategic choice of retailers and the strategic choice of retailers has the most significant impact on the strategic choice of farmers.

Introduction

Chinese government’s 20th annual report points out that integrated development between urban and rural areas is an inherent requirement for high-quality development, and promoting green and low-carbon economic and social development is the key link in high-quality development¹. It is a systematic project to develop the recycling of waste electrical appliances and electronic products in urban and rural areas. Electrical and electronic products are necessities in the public’s daily life and play an important role in economic and social development². Due to the large recycling capacity, and the high financial and environmental benefits of waste electrical and electronics, the recycling of WEEE is one of the keys to realizing the recycling economy and green ecology^3,4. Rural WEEE refers to all kinds of electrical and electronic equipment and products eliminated, no longer used, or damaged in rural areas, including home appliances, office equipment, small electronic equipment, electronic toys, lamps, batteries, etc. From 2015 to 2022, the total number of electrical and electronic products such as televisions, refrigerators, washing machines, room air conditioners, microcomputers, and mobile phones has reached 6126 units per 100 households. As shown in Fig. 1, the annual ownership of 100 rural households is on the rise, accounting for 42.7% of the national total. According to the China Waste Electrical and Electronic Equipment Recycling Comprehensive Utilization of Industry white paper 2024 forecast statistics, there is little significant difference between urban and rural ownership of major electrical and electronic products. However, mobile phone ownership in rural areas is significantly higher than that in the town. According to the four-year survey of processing enterprises conducted by the China Institute of Home Appliances, the theoretical volume of the first batch of WEEE to be disposed of in 2023 is predicted to be about 260 million pieces, year on year growth of 12%⁵, of which rural areas account for nearly half. In the context of urban–rural dual structure, due to economic factors and the lack of recycling infrastructure, the construction of perfect electrical and electronic products recycling systems in rural areas is facing challenges. In addition, residents’ awareness of environmental protection is relatively low. Some places even lack relevant policies and regulations to guide and standardize the recycling of electrical appliances and electronic products in rural areas, leading to the lag of the recycling industry. The long-life cycle of products in rural areas makes the recycling of electrical and electronic products diverse and relatively complex to handle and categorize. Due to the above reasons, at present, rural WEEE are mainly recycled by mobile hawkers and then transported to urban recycling stations.

Fig. 1.

Million ownership of electrical and electronic consumer durables by rural and urban residents.

To standardize recycling of waste electronics, China introduced EPR (Extended Producer Responsibility) in 2012, making producers accountable for the product lifecycle. EPR emphasizes that producers are responsible for the environmental performance of the whole life cycle of products, give full play to the leading advantages of production enterprises, and make all stakeholders jointly bear the relevant responsibility to manage the important responsibility mechanism for the environmental externalities of electrical and electronic products⁶. Under the series of incentive policies based on EPR, many manufacturers have carried out product ecological design and recycling. China’s cities have established the corresponding recycling system, but problems such as frequent irregular military private demolition, incomplete extended responsibility, and the lack of responsibility-sharing incentive mechanism of various stakeholders are still prominent⁷. There is also a lack of connection mechanism with the recycling of rural WEEE. At present, the supply and marketing cooperative system has 58,000 recycling outlets for renewable resources at or below the county level, 1515 sorting centers, and 210 recycling bases (parks). The recycling network of China Supply and Marketing Cooperative is distributed in urban and rural areas throughout the country. Through cooperation with local governments and the construction of its own network, the supply and marketing cooperative system has played an important role in promoting the recycling and utilization of renewable resources. In the field of rural recycling, at present, China’s supply and marketing cooperatives are actively guiding and promoting the extension of the renewable resources recycling system to the rural areas. However, the renewable resources recycling industry of the supply and marketing cooperatives is facing many challenges. Falling prices and rising operating costs are one of the main problems. In addition, most of the rural renewable resource enterprises established by the supply and marketing cooperatives have problems such as weak infrastructure, lagging technology, a single business model, and insufficient strength. Given the above situation, combined with the practical difficulties of incomplete extension of the EPR system in the field of rural recycling, it is important to explore the recycling of rural WEEE under the joint action of the EPR system and the "dual regulation system" of supply and marketing cooperatives. In the process of integrated urban and rural development and sustainable development, the EPR system provides an opportunity for transforming the supply and marketing cooperatives and the renewable resources industry, strengthening economic links between urban and rural areas, promoting the organic flow of renewable resources, and stimulating urban–rural integration and rural revitalization.

At present, there are few documents on the recycling of WEEE in rural areas of China. The research perspective of WEEE recycling mainly includes WEEE recycling system, EPR system, government policy, and environmental NGOs. The research topics mainly include recycling system exploration and search of influencing factors, system evaluation, recycling strategy, and market analysis, and production prediction of WEEE, etc. In the study of the EPR system. Cai et al.⁸ and Li et al.⁹ discuss different environmental tax policies designed for manufacturers to reduce environmental hazards and resource waste of products from the source and then achieve the maximization of social welfare. Tian¹⁰ explores the current situation of the implementation of the EPR system in China and point out that an effective EPR system is the institutional guarantee to promote the green development of various production enterprises. Shan and Yang¹¹ discuss the strategic choices of producers, recyclers, and governments, as well as the implementation mechanism of the Chinese EPR system and its influencing factors. Liu et al.¹² argue that it is important to build an "Internet+ " green community, strengthen residents’ green consumption concept, and improve the subsidy scope of the fund system to ensure the good development of the EPR system. Although the extended producer responsibility system mainly emphasizes the responsibility of producers, in fact, different roles such as consumers, sellers, recyclers, and the government are all important in terms of responsibility sharing. Li and Zheng¹³ thoroughly analyze the practical problems such as the difficulty of formal recycling of WEEE and study the problem of responsibility sharing among the members of the supply chain. Pazoki and Zaccour¹⁴ have studied the issue of responsibility sharing for product recovery and its relationship with the design of an extended responsibility system. They believed that the design of the EPR system and the distribution of responsibility in the supply chain must be conducted at the same time.

In terms of research methods, the research on multi-agent participation in the recovery strategy is mainly based on the game theory. Ma¹⁵ analyze the influence of producer responsibility extension on the main strategy based on the game theory. Guo and Wang¹⁶ construct an evolutionary game model between the local government, the recycling and treatment enterprise, and the local public, analyze the behaviors of the three stakeholders, and put forward a long-term strategy choice for the stakeholders in the recycling and treatment of WEEE. Similarly, Wang et al.¹⁷ highlight the role of three stakeholders of government, processing providers, and consumers in the recycling of WEEE, focusing on the evolution and stability strategies of different development stages of recycling. Zhu¹⁸ construct a three-party game model between the government, online recyclers, and offline recyclers, and analyze the three-party strategy selection and interactive relationship. However, the above studies fail to involve the recycling of renewable resources in rural areas while recycling in rural areas mainly focuses on policy analysis. In the simulation stage of a mathematical model, most literature is simulated with MATLAB. The combination of evolutionary game and system dynamics, however, is rarely studied. Fu et al. Fu et al.¹⁹ establish an evolution game model between the government and the recycling processor in the recycling of WEEE and carry out a system dynamics analysis to study the evolution of the strategies of both sides. Tu et al.²⁰ consider the impact of public participation, construct a three-way game model between government environmental protection departments, electrical and electronic manufacturers, and the public based on the non-cooperative evolution game, and adopt the system dynamics method for simulation analysis. Luo et al.²¹ use the method of system dynamics to build the system dynamics model of the government, enterprises, consumers, and other multiple stakeholders, pointing out that the market environment will also affect the recovery strategy of multiple stakeholders.

In summary, there is insufficient research on the recycling of WEEE in rural areas. There is a lack of effective linkage mechanism for the recycling of waste electrical and electronic products between urban and rural areas; The EPR system has not been fully extended in rural areas, and there is limited research on dual regulation; However, research on multi-agent participation in recycling strategies is mainly based on game theory, with less attention paid to the important role of farmers in the reverse logistics recycling system. Therefore, this paper comprehensively considers the integrated development of urban and rural areas and the standardized industry system, combined with the extension of producer responsibility and the "dual regulation system" of supply and marketing cooperatives, establish a three-level recycling network system relying on the supply and marketing cooperative system under the extended producer responsibility system: farmers (village level), supply and marketing cooperatives (towns) and sellers (counties) and construct a recovery model of rural WEEE and an evolutionary game system dynamic model. We aim to explore the mechanism of “dual regulation” to promote the recycling of rural WEEE. According to system dynamics theory, we analyze the strategy selection and interaction relationship of each subject in the evolution process, and the main influencing factors of different evolutionary stages and dynamic processes of the system.

Problem description and theoretical analysis

Problem description

This paper explores a recycling model for rural WEEE, leveraging the multi-level structure of township supply and marketing cooperatives, recycling sites, and county brand sellers. Farmers sell their waste electronics to the cooperatives, which serve as recycling distribution centers. The cooperatives then receive, categorize, and store the waste, adhering to the unified recovery model outlined by the extended producer responsibility system. In this recycling model, farmers need to actively engage in the recycling plan and collect and deliver WEEE to the designated recycling points of the supply and marketing cooperatives. The cooperatives, on the other hand, have multiple responsibilities. Firstly, they oversee and formulate recycling policies to encourage farmer participation ensuring that farmers are motivated to sell their waste electrical appliances to the cooperatives. Secondly, the cooperatives collect and dispose of the waste appliances, receiving them from farmers, cleaning, performing basic disassembly, classifying them to meet reuse or recycling standards, and cooperating with sellers to provide them with recycled waste electrical appliances. Thirdly, the cooperatives conduct environmental education and promotional activities to enhance farmers’ and community residents’ awareness and attention towards recycling waste electrical appliances. Fourthly, a supervision mechanism is established to guarantee supply and marketing cooperatives and sellers adhere to prescribed procedures and standards. Regular assessments are conducted to identify system efficiency and areas for improvement, aiming for the sustainability and long-term success of the entire recycling system.

The sellers, however, are tasked with receiving and reusing the products. They acquire the waste electrical appliances from the supply and marketing cooperatives and either reuse or sell them, including through repairs, recycling parts, or direct sales. Sellers must ensure their operations are compliant with laws and regulations and meet relevant standards, thereby safeguarding farmers’ rights and product quality. Additionally, they are expected to support recycling programs, encouraging farmers to recycle old products or offering them sustainable alternatives.

Method selection

Evolutionary game theory is expanded based on the classical game theory and biological theory. Its core theory includes replica dynamic (RD) and evolutionary stability strategy (ESS)²² evolutionary theory of basic assumptions is divided into two kinds: one is the rational choice hypothesis, mainly refers to the optimal action plan through individual game behavior. The other is the limited rational hypothesis, mainly based on the existing knowledge and ability, individuals to make limited rational reasoning. Due to the limited rational setting of the game decision, the optimal equilibrium may not be found at the start. However, the optimal state will eventually be reached through continuous game and strategy adjustment. In this process, it can recover to the evolved equilibrium state even if it is affected by a small number of external conditions^23,24. Yan Yan²⁵ research analyzes the evolution of three evolution game examples and further describes "limited rational replication under the hypothesis of dynamic" and "evolutionary stability strategy" deduction process. In the process of WEEE recycling, SMC, distributors, and farmers’ tripartite behavior choice is uncertain, but the optimal strategy choice is mutual influence and dependence, the existence of many factors leads to the three parties in the behavior strategy selection is not in a state of completely rational, which makes the three parties in the initial stage of the game cannot directly find the optimal strategy, need a long time of game behavior, through constantly to learn, imitate other strategies, trial and error, modify their strategy to achieve the goal of maximizing. Dynamics (System Dynamics) is a method proposed by Jay W. Forrester in 1961 to study causal patterns of systems²⁶. The approach aims to find out how policy, decision-making, structure, and time delays relate to each other and affect the growth and stability of a given system. Therefore, it can build an effective management model thinking system, and become an effective means to master the dynamic behavior characteristics and understand the structure of complex systems. According to the evolutionary game of the recovery strategy of rural WEEE, the dynamic simulation analysis based on the stability of each equilibrium and the main factors affecting the stability of the strategy of farmers and sellers is analyzed. The recycling of WEEE in rural areas is a systematic problem. Supply and marketing cooperatives, sellers, and farmers must work together to ensure the stable and efficient recycling of WEEE. If the recovery strategy changes, it will inevitably have a positive or negative impact on the recovery behavior of the other two parties, and will also affect the overall recovery system. In the WEEE recycling system, the three are very closely dependent, which is the network through different factors. Through the above analysis, it can be concluded that the behavior strategies of supply and marketing cooperatives, sellers, and farmers are affected by various factors, which is not an invariable process. In this case, this paper adopts the method of combining evolutionary game system dynamics to study the recycling mode of rural WEEE. The model performs a three-way strategic evolution game, focusing on the analysis of the stability of the equilibrium point, while considering the influence of the change of the evolution parameters on the stable equilibrium. The overall architecture of the modeling is shown in Fig. 2.

Fig. 2.

The overall architecture of the model.

Model building

Game base model

Model assumptions

Hypothesis 1: Participant subject. To promote rural WEEE efficient recycling needs SMC, distributors, and farmers direct stakeholders work together, therefore, consider an “SMC”, “sellers” and “farmers” tripartite game model, and the premise in incomplete information, limited rational decision, in WEEE recycling to maximize their interests as a premise.

Hypothesis 2: The policy spaces. In the process of a three-party evolutionary game, the strategy of supply and marketing cooperatives is “strong supervision” and “weak supervision”. The strategy of sellers is “positive” and “negative”. The farmers’ strategy is “participation” and “no participation”. The corresponding strategy probabilities are respectively α, β, and γ [0,1]. In the recycling game of waste electrical appliances and electronic products, the income of each game subject will be affected by the decision of the other two game subjects. So, WEEE recycling tripartite game strategy combination as follows: (strong regulation, positive, participation), (strong regulation, positive, not to participate), (strong regulation, negative, participation), (strong regulation, negative, not to participate in), (weak regulation, active, participation), (weak regulation, positive, not to participate), (weak regulation, negative, participation), (weak regulation, negative participation, not to participate in). Assuming that the probability of the supply and marketing cooperative adopting a “strong regulatory” decision is α, The probability of supply and marketing cooperatives adopting “weak supervision” is 1- α (0 ≤ α ≤ 1); Similarly, assuming that the probability of a recycling seller adopting an “active commitment” behavior decision is β, the probability of recycling sellers taking “negative responsibility” is 1- β (0 ≤ β ≤ 1). Assuming that the probability of farmers adopting “participation” behavior in decision-making is γ, the probability of farmers adopting “non participation” behavior in decision-making is 1- γ (0 ≤ γ ≤ 1). Then the strategy selection of the above game participants can be simplified as (1,1,1), (1,1,0), (1,0,1), (1,0,0), (0,1,1), (0,1,0), (0,0,1), (0,0,0,).

Hypothesis 3:Referring to Ma 's¹⁵ hypothesis.Cost Time, manpower, and administrative costs are paid by the supply and marketing cooperatives when they are in a state of strong supervision C1. Farmers do not participate in the recycling of waste electrical appliances and electronic products, and the additional environmental protection publicity cost paid when the supply and marketing cooperatives are in a state of strong supervision is P1. The seller actively undertakes the cost C2 of introducing advanced technology and research and development equipment in the recycling of WEEE. The time and labor cost consumed for farmers to participate in the recycling of WEEE is C3. Different models of waste electrical appliances and electronic products recycling cost is the same. In the recycling process of the WEEE, the WEEE that have not been recovered by the sellers will be sold to the informal recycling stations by the farmers. The government punishes the negative commitment state of the recycling distributor and rewards the state of positive commitment. The reputation benefits, social benefits, administrative costs, and labor costs in the recycling system of WEEE can be quantified, and all exogenous variables are positive.

Hypothesis 4: Earnings. The income brought by the WEEE of the supply and marketing cooperatives is E1. E2 of the seller from the recycling of WEEE by the supply and marketing cooperatives. The seller actively undertakes the reputation V1 of WEEE. Farmers sell WEEE to sellers’ farmers E3. E'3 from farmers selling WEEE to farmers in informal places. The financial subsidy issued by the government to the seller when the supply and marketing cooperatives are in the state of active undertaking and the supply and marketing cooperatives are in the state of strong supervision S1. The government of the government F1 when the supply and marketing cooperatives strengthen supervision. The credibility of supply and marketing cooperatives under strong supervision G. Farmers participate in the recycling of WEEE, and the supply and marketing cooperatives are in a state of strong supervision to bring psychological benefits to farmers M1. The seller actively undertakes the recycling of WEEE, and the participation of farmers in recycling brings benefits to the environmental improvement of farmers R1. The additional benefit of the farmer participating in the recovery to the seller is A1. When the seller is in a state of active undertaking, the farmers will participate in the recycling of waste electrical appliances and electronic products to receive an additional monetary subsidy S2.

Income matrix

According to the hypothesis above, the income matrix of the evolutionary game model between the supply and marketing cooperatives, sellers, and farmers is constructed, as shown in Table 1 below.

Table 1.

Income matrix of the evolutionary game among supply and marketing cooperatives, sellers, and farmers.

Game subject	Marketing cooperative
Seller	Farmer	Strong regulation (α)	Weak regulation (1-α)
Actively undertake (β)	Take part in (γ)	E1 − C1 + G − S1	E1
		E2 + V1 − C2 + S1 + A1 − S2	E2 + V1 − C2 + A1 − S2
		E3 − C3 + M1 + R1 + S2	E3 − C3 + R1 + S2
	Drop out of (1-γ)	E1 − C1 + G − P1 − S1	E1
		E2 + V1 − C2 + S1 + A1 − S2	E2 + V1 − C2
		E′3	E′3
Negative bear (1-β)	Take part in (γ)	E1 − C1 + F1 + G	E1
		E2 + G	E2
		E3 − C3 + M1	E3 − C3
	Drop out of (1-γ)	E1 − C1 − P1 + G + F	E1
		E2 − F	E2
		E′3	E′3

Model solution

To and respectively indicate the expected income of supply and marketing cooperatives adopting the strategy of “strong supervision” and “weak supervision”, and their average income is recorded as. According to the payment matrix of game income, the expected return and average expected return of supply and marketing cooperatives with “strong supervision” and “weak supervision” strategies can be calculated as follows:

1

2

3

Similarly, the expected benefits of the “positive” and “negative” strategies , and the average expected respectively:

4

5

6

Similarly, the expected benefits of the “participation” and “no participation” strategies can be obtained , and the average expected return respectively:

7

8

9

The core problem of the evolutionary game is to solve the stability strategy (ESS) and the replication dynamics. According to formula (1)–(9), the system replication dynamic equation system is obtained:

10

11

12

Dynamic model of the evolutionary game system

In the rural recycling system of WEEE, the supervision proportion of supply and marketing cooperatives, the responsibility of sellers, and the participation of farmers are set as horizontal variables, the supervision of supply and marketing cooperatives, the responsibility of sellers and the participation of farmers over time are set as rate variables, and the other influencing factors are set as auxiliary variables. The association between the quantities is determined from the replication dynamic equation. According to the theoretical integration of the evolutionary game dynamic replication system²⁷, based on the replication dynamic system Eqs. (10), (11) and (12), the dynamic model of supply and marketing cooperatives, sellers and farmers is established as shown in Fig. 3.

Fig. 3.

Evolutionary game system dynamics model of rural WEEE recycling.

Example analysis

Analysis of the system evolution and stability

According to Friedman’s method²⁸, the evolutionary stability strategy of a system of differential equations can be obtained from the local stability analysis of the Jacobian matrix of this system. The Jacobi matrix of the system according to formulas (10), (11) and (12) is:

According to the above copied dynamic differential Eqs. (10), (11), and (12) to solve the equilibrium points of the evolutionary game model, Ritzberger and Weibull²⁹ believe that the evolutionary stability strategy is a pure strategy when the information asymmetry condition of the asymmetric game is established. Therefore, discuss 8 equilibrium points satisfied: E1 (0,0,0), E2 (0,0,1), E3 (0,1,0), E4 (0,1,1), E5 (1,0,0), E6 (1,0,1), E7 (1,1,0), E8 (1,1,1). These 8 equilibrium points are located at the boundary position of the evolutionary game solution of rural electrical and electronic product recovery; and meet 0 α, β, and γ 1. The regions enclosed by the equilibrium point are all the feasible solutions of the evolutionary game model. The eight equilibrium points were substituted into the Jacobian matrix and the eigenvalues of the corresponding Jacobian matrix were calculated one by one. Using the Lyapunov stability condition, the stable state of the game system can be tested by the eigenvalues. The progressive stability point of the system refers to the eigenvalues of the equilibrium points E1-E8 that are all less than 0, otherwise, the point is unstable. If the equilibrium point stability conditions are met, see Table 2, which is (1 (0, (2 (0, (3 (0. Then the point is the evolutionary stability strategy point.

Table 2.

Equilibrium point evolution stability conditions.

Equant equation	Evolutionary stability conditions	Stable state	ESS determination conditions	Ideal
E1(0,0,0)	F1-C1 + G-P1 < 0	Instability points or the ESS	①	Unsatisfactory
	V1-C2 < 0
	E3-C3-E4 < 0
E2(0,1,0)	G-C1-P1-S1 < 0	Instability points or the ESS	②	Not ideal
	C2-V1 < 0
	E3-C3 + R1 + S2–1 < 0
E3(0,0,1)	F1-C1 + G < 0	Instability points or the ESS	③	Not ideal
	A1-C2-S2 + V1 < 0
	C3-E3 + E4 < 0
E4(0,1,1)	G-C1-S1 < 0	Instability points or the ESS	④	Ideal
	C2-A1 + S2-V1 < 0
	C3-E3-R1-S2 + 1 < 0
E5(1,0,0)	C1-F1-G + P1 < 0	Instability points or the ESS	⑤	Unsatisfactory
	A1-C2 + F1 + S1-S2 + V1 < 0
	E3-C3-E4 + M1 < 0
E6(1,1,0)	C1-G + P1 + S1 < 0	Instability points or the ESS	⑥	Not ideal
	C2-A1-F1-S1 + S2-V1 < 0
	E3-C3-E4 + M1 + R1 + S2 < 0
E7(1,0,1)	C1-F1–G < 0	Instability points or the ESS	⑦	Not ideal
	A1-C2-G + S1-S2 + V1 < 0
	C3-E3 + E4-M1 < 0
E8(1,1,1)	C1-G + S1 < 0	Instability points or the ESS	⑧	Ideal
	C2-A1 + G-S1 + S2-V1 < 0
	C3-E3 + E4-M1-R1-S2 < 0

In conclusion, according to the stability analysis results, there are 8 stability states, among which the ideal state has an equilibrium point (1,1,1) , an equilibrium point (0,1,1), The above equilibrium point realizes the supply and marketing cooperatives under the premise of strong or weak supervision, which is conducive to the recycling of rural waste electronic. Fact, stand in the manager’s point of view, the equilibrium point (1,1,1)Need for supply and marketing cooperatives to carry out strong supervision, pay a certain amount of material resources cost can realize the positive behavior of sellers and farmers, and the equilibrium point (0,1,1)Under the weak supervision of the supply and marketing cooperatives, the positive behavior of both can be realized, saving the regulatory resources, which is the Pareto Optimality β state of the system, but the realization of this state requires the sellers and farmers to have a high autonomous behavior. Meanwhile, there are four less-desirable equilibrium points in the system, (0,1,0), (0,0,1), (1,1,0), (1,0,1). The above four equilibrium points can only realize the active commitment of sellers or the participation of farmers, so they are in the unsatisfactory state of recycling of WEEE, and the equilibrium points1 (0, 0,0) and 5 (1, 0,0) When stable, the seller chooses to bear the negative, Farmers choose not to participate, Is one of the most undesirable states of system evolution, not conducive to the recycling of waste electrical appliances and electronic products. At present, the recycling of rural electrical and electronic products needs strong supervision by the government to keep the system in a relatively good state. Therefore, assume that C1-F1-G + P1 < 0 and C1-G + P1 + S1 < 0, so the stability of the above equilibrium point is as follows: (1) When the condition ⑧ is met, Equilibrium point 8 (1, 1,1) is stable. At this time, the credibility of the strong supervision of supply and marketing cooperatives is higher than the sum of the subsidy cost and time and human administrative costs, The sum of the additional benefits that the seller chooses to actively undertake, the subsidies and the sum of its reputation benefits is higher than the costs, the additional subsidies of the farmers’ participation and the credibility of the supply and marketing cooperatives, The normal income and psychological benefits of farmers, the benefits of environmental improvement, the sum of sellers’ subsidies are higher than their costs and the benefits of hawkers, At this time, the supply and marketing cooperatives choose a strong supervision strategy, Dealers choose to actively undertake the strategy, farmers choose the participation strategy, The evolution result is an ideal evolution state of the system. (2) When the condition ⑤ is met, Equilibrium point 5 (1, 0,0) Stable, At this time, the credibility of the strong supervision of supply and marketing cooperatives is higher than the sum of their time, human, and administrative costs and environmental protection publicity costs, Between the sum of the cost that the seller chooses to bear and the subsidy of the seller to the farmer and the sum of the fine of the seller, the subsidy of the supply and marketing cooperatives to the seller and the reputation benefits of the seller, when the sum of the time cost of the farmer participating in the recovery and the benefits of selling to the vendor is higher than the psychological benefit and normal benefits of their participation, Supply, and marketing cooperatives choose strong supervision, and sellers choose to bear negatively, Farmers choose not to participate, This state is not system-optimal. (3) When the condition ⑥ is met, Equilibrium point 6 (1, 1,0) is stable. At this moment, The credibility of the strong supervision of supply and marketing cooperatives is higher than the sum of the seller subsidies, environmental protection publicity costs, time and human administrative costs, The cost that the seller chooses to bear and the subsidy from the seller to the farmer are lower than the additional income borne by the seller and the fine imposed by the supply and marketing cooperative to the seller, The normal income and psychological benefits of farmers, the benefits from environmental improvement, and the sum of seller subsidies that are lower than their costs and the benefits of hawkers, At this time, the supply and marketing cooperatives choose a strong supervision strategy, Dealers choose to actively undertake the strategy, and farmers choose not to participate in the strategy, This state is the result of a less-than-optimal evolution of the system.(4) When the condition ⑦ is met, Equilibrium point 7 (1, 0,1) is stable. At this moment, The credibility of the strong supervision of supply and marketing cooperatives is higher than the sum of the subsidy costs and time and human administrative costs, The sum of the additional benefits that the seller chooses to actively undertake, the subsidies and the sum of its reputation benefits are lower than the costs, the additional subsidies of the farmers’ participation and the credibility of the supply and marketing cooperatives, when the sum of the time cost of the farmers’ participation in the recovery and the benefits of selling to the vendors is lower than the psychological benefit and normal benefits of their participation, At this time, the supply and marketing cooperatives choose a strong supervision strategy, Sellers choose negative undertaking strategy, farmers choose participation strategy, This state is the result of a less-than-optimal evolution of the system.

In fact, the most ideal evolution state of the system is the following situation (5), but it requires the sellers and farmers to have a high consciousness, which is the future evolution direction of the system. The following judgment conditions are given for the case (5).

(5) When the condition ④ is met, Equilibrium point 4 (0, 1,1) is stable. At this time, the credibility of the strong supervision of supply and marketing cooperatives is lower than the sum of the subsidy cost and time and human administrative cost, The sum of the additional benefits above the cost of the seller and the additional subsidy of farmer participation, The sum of farmers 'normal income and environmental improvement income and additional subsidy income is higher than the time cost of their farmers’ participation in recovery, At this time, the supply and marketing cooperatives choose the weak supervision strategy, Dealers choose the active participation strategy, farmers choose the participation strategy, This evolution results in the ideal Pareto Optimalityβ state of the system. Through theoretical analysis and stability of the evolution of the system, but the theory of the lack of certain intuition, also difficult to reveal the evolution of the system and the path, so the following will through numerical simulation, intuitively reveal the evolution of the initial path, the value of the evolution results, and the sensitivity of the important parameters.

Dynamic simulation analysis

Conduct research on rural recycling vendors and home appliance production and recycling enterprises such as Love Recycling, Gree, Haier, as well as research institutes and industry associations such as China Material Recycling Association and China Household Appliance Research Institute. Consider the stability conditions of equilibrium point E8 (1,1,1) and consult experts in relevant fields, Referring to the parameter setting and assignment method of Xie et al.³⁰ and Shen et al.³¹, assign values to the model. Initial time = 0, final time = 20, time step = 0.25, E₁ = 4, C₁ = 0.2, S₁ = 0.1, F₁ = 2, G = 0.2, P₁ = 0.3, E₂ = 5, V₁ = 0.3, C₂ = 1.5, E₃ = 1.3, E’₃ = 1.4, A₁ = 0.3, C₃ = 0.1, M₁ = 0.5, R₁ = 0.4, S₂ = 0.2.

Tripartite subject simulation analysis

When the initial strategy of the tripartite player is (0.8,0.01,0.01), the strategy evolution path of the tripartite player is obtained as shown in Fig. 4a.

Fig. 4.

Tripartite Subject Simulation Analysis diagram.

As can be seen from the figure above, when the supply and marketing cooperatives adopt the state of “strong supervision”, it can effectively drive the sellers to choose the “active undertaking” strategy, and the farmers will eventually choose the “participation” recovery strategy. The time for the three parties to reach the stability strategy is different. The supply and marketing cooperatives first reach the stable state, then the seller, and then the farmers. It can also be seen that the speed of farmers’ “participation” strategy begins to increase only after the sellers reach the stable state, indicating that the strategy choice of sellers has a significant impact on the farmers.

(2) When the initial strategy of the tripartite player is selected as (0.01,0.8,0.01), the strategy evolution path of the tripartite player is obtained as shown in Fig. 4b.

As can be seen from the figure above, when the seller chooses the strategy an “active undertaking”, it can effectively promote the strategy selection of the supply and marketing cooperatives and the farmers to be stable, and the supply and marketing cooperatives will eventually choose the “strong supervision” strategy, and the farmers will choose the “participation” strategy. Since the starting strategy of supply and marketing cooperatives is “weak supervision”, it will have a certain inhibitory effect on the “active undertaking” of the sellers. When the strategy choice of supply and marketing cooperatives tends to be “strong supervision”, the strategy of driving the sellers tends to be “active undertaking”. It can be seen that the strategic choice of the supply and marketing cooperatives has an important influence on the sellers, and the strategic choice of the sellers has a significant impact on the farmers.

(3) When the initial strategy of the subject of the tripartite game is selected (0.01,0.01,0.8), the strategy evolution path of the subject of the tripartite game is shown in Fig. 4c.

As can be seen from the figure above, when the initial strategy of farmers is to “participate” in the recovery, it can also drive the strategy selection of supply and marketing cooperatives and sellers to be stable. The supply and marketing cooperatives will eventually choose the state of “strong supervision”, and the sellers will finally choose the strategy of “active responsibility”. As the initial strategy of the supply and marketing cooperative and the sellers hold a negative attitude towards the recycling of WEEE products, the choice of “participation” strategy of farmers has decreased, but the rapid “strong supervision” strategy of the supply and marketing cooperative stabilized the decline of the farmers’ strategy, and at the same time also led the strategy choice of sellers to “actively undertake”. The above three cases can be seen, in the rural WEEE recycling process, SMC, distributors, farmers tripartite game main body, when there is a main body actively dealing with WEEE recycling, will promote the other two parties involved in the waste effective recycling of electrical and electronic products, eventually evolved into the tripartite cooperation. Sellers are greatly influenced by the choice of SMC strategy. In the recycling process of WEEE, sellers actively introduce new technologies and conduct equipment development, which is costly for them. It is necessary to provide certain subsidies to make up for it and mobilize sellers’ enthusiasm. Therefore, in the recycling of waste electrical and electronic products, the role of SMC should be fully utilized to reduce the cost of sellers, improve the enthusiasm of sellers and maintain the stability of the recycling system.

Simulation and analysis of exogenous variables

In the above paper, the strategy selection of the three game subjects in the recovery is analyzed. No matter what strategy the supply and marketing cooperatives, sellers, and farmers initially choose, the final stable state is the three-party cooperation. However, in addition to the choice of strategies, the tripartite subjects will also be influenced by various external factors. To explore the influence of different influencing factors on the system, this paper assigns the exogenous variables under the established strategies of the tripartite game subjects; and seeks the influence degree of different exogenous variables.

(1) The influence of exogenous variables of supply and marketing cooperatives on the evolution of the tripartite subject strategy

In rural WEEE recycling systems, SMC exogenous variables including environmental protection cost, government credibility, and government administrative costs, keep the rest of the variable unchanged, by adjusting the initial value of a variable in SMC exogenous variable simulation, to explore the tripartite subject strategy evolution path in compliance with Fig. 5.

Fig. 5.

The impact of exogenous variables on the strategies of supply and marketing cooperatives.

In the simulation, the initial strategy of supply and marketing cooperatives, sellers, and farmers is (0.1,0.1,0.1). As can be seen from the simulation diagram, the change in the exogenous variables of the supply and marketing cooperatives will not have an impact on the overall final strategy of the three parties, and will eventually tend to participate in the recovery of WEEE. The credibility of supply and marketing cooperatives has a positive impact on the supervision level of supply and marketing cooperatives. The improvement of credibility can drive the development of supply and marketing cooperatives to a strong supervision level. To improve the recognition of sellers and farmers and improve the public’s satisfaction and trust in the supply and marketing cooperatives, the supply and marketing cooperatives will always maintain a strong supervision state. The cost of environmental protection publicity and the administrative cost of supply and marketing cooperatives have the greatest impact on the strategy selection of supply and marketing cooperatives; and are inversely proportional to the strong supervision level of supply and marketing cooperatives. SMC to promote the rural WEEE recycling system’s stable and efficient operation, through subsidies and implement preferential policies to improve the positive degree of sellers, environmental protection publicity and education of farmers to improve farmers environmental consumption concept, encourage farmers to participate in the WEEE recycling, but SMC is too high; because the cost and benefits cannot be balanced, will restrain the SMC take strong regulatory will, even choose a weak regulatory strategy to reduce costs. As can be seen from the simulation results, the change of regulatory strategy will drive the change of sellers’ and farmers’ strategy choice, SMC strong regulatory level of speed and sellers actively take trend speed, farmers participate in the trend speed is proportional to the overall trend for SMC regulatory level will first improve, drive the sellers and farmers involved in waste electrical electronics recycling process, after reaching a certain extent, regulatory level will begin to decline, towards the weak regulatory development, but sellers and farmers will always stay in actively participate in the stable state.

(2) The impact of the exogenous variables on the seller’s strategy

In the recycling system of rural WEEE, the exogenous variables of the seller include reputation benefit, research and development cost, government subsidies, and government fines. Under the condition of keeping the other variables constant, the initial value of the certain variable is adjusted to explore the evolution path of the seller strategy. As shown in Fig. 6.

Fig. 6.

The impact of the exogenous variables on the seller’s strategy.

It can be seen from the above simulation results that when the seller does not consider the main strategy choice of the other two parties, it will also be affected by other factors for whether to undertake the recycling of WEEE actively; and will make the right choice according to the cost and the benefits they can get. Sellers increase recycling technology introduction and new equipment research and development costs, although the income balance is broken and slowing the trend of strategy choice, with the continuous development and use of technology and equipment, waste electrical and electronic rare metals in the recycling rate is high, increased the seller own income, also supports the seller continuously strengthen positive strategy level. The sellers actively undertake the recycling of WEEE, which will also establish a good corporate image in the society, and improve the seller’s visibility.

In the simulation, the initial strategy of supply and marketing cooperatives, sellers, and farmers is set to (0.1,0.1,0.1). As Can be seen by the simulation diagram, in the rest of the two main bodies to the seller strategy selection influencing factors, SMC penalties for sellers’ negative strategy selection of the role of the biggest, when the heavier, or subsidies for sellers, the more can speed up the sellers choose “positive” strategy. For supply and marketing cooperatives, the number of subsidies for sellers will not affect the rate of the increase of “strong supervision” of supply and marketing cooperatives in the early stage, and when the sellers reach a stable state and the recovery system is more perfect, the supply and marketing cooperatives with high subsidies begin to tend to weak supervision. SMC for negative sellers’ fines strength, for SMC did not have much influence, and the influence of the seller is very big, sellers to ensure their earnings are positive, will choose to actively take strategy, increase the introduction of new technology and new equipment research and development, ensure the WEEE recycling rate is high. General, sellers to improve their earnings and avoid SMC high fines, will choose to actively undertake WEEE recycling, strengthen the cost of technology and equipment investment, in exchange for WEEE priced recycling high recovery, at the same time sellers choose actively will also have higher reputation in the society, higher visibility, can also get the government subsidies and tax policy, more determined sellers to actively undertake the choice of strategy, form a virtuous cycle.

(3) The influence of farmer exogenous variables on the strategy selection of game subjects in rural WEEE recycling system, affect the farmer strategy selection of exogenous variables including environmental improvement benefits, enterprise subsidies, cost, and psychological benefits, to ensure the rest of the variables, by adjusting the four exogenous variables of farmers alone simulation, to explore the influence of exogenous variables on farmers strategy evolution path. As shown in Fig. 7.

Fig. 7.

Effects of exogenous variables on farmers’ strategies.

As can be seen from the above simulation diagram, in addition to the factors of farmers themselves, sellers will also have an impact on the choice of farmers’ strategies. The number of subsidies to farmers will not have much impact on the choice of sellers’ strategy, but it will have a greater impact on farmers, and the more subsidies, the higher the psychological willingness of farmers to participate in the recycling of WEEE.

In the simulation, the initial strategy of supply and marketing cooperatives, sellers, and farmers is set to (0.1,0.1,0.1). As can be seen from the simulation diagram, when farmers consider whether to participate in the recycling of WEEE, their psychological benefits, the cost of participation in the recovery, and environmental improvement benefits will have a certain impact on farmers, among which the cost of participation and the psychological benefit of consumers have the biggest impact. When involved in the cost of WEEE recycling is too high, the willingness of farmers to participate in the more serious, farmers choose to participate in recovery of the slower, but ultimately will choose to participate in recycling, and due to the improvement of people’s living standards, farmers to the requirements of the living environment will become high, as the SMC in environmental protection propaganda, people of the environmental concept, more able to promote farmers involved in the WEEE recycling process, but if the cost is too high, farmers after try will choose “not” participate in the strategy. When farmers choose to participate in WEEE recycling, if SMCs constantly choose to strengthen the regulation of WEEE recycling, widely publicized WEEE recycling; will let farmers produce a kind of behavior recognized psychological effect, to strengthen farmers’ behavior, farmers’ strategy choice convergence speed up.

Conclusion

Research conclusions

This paper considers the rural WEEE recycling strategy, focusing on the EPR system and SMC regulation synergy, establishing the village (farmers), villages and towns (SMC), and county (seller) tertiary recycling network system, as the basis of effective promote WEEE recycling. Constructing an Evolutionary Game Model and Evolutionary Game System Dynamics Model for the Recycling Mode of Rural Waste Electrical and Electronic Products. Then, the three parties’ stable equilibrium state and strategy selection are analyzed, and vensin software is used to analyze the evolution path of the three parties under different circumstances. The main study conclusions are summarized as follows: (1) Three subjects initially will choose to actively respond to WEEE recycling.when there is a main body actively dealing with WEEE recycling, will promote the other two parties involved in the waste effective recycling of electrical and electronic products, eventually evolved into the tripartite cooperation..(2) but in the end can achieve strong regulation, actively undertake, and participate in the recovery stability strategy depending on the benefits of the harvest and spending cost of itself is reasonable, when their interests are positive, the three body will choose to face the WEEE recycling. (3)The strategic choice of supply and marketing cooperatives has the most significant impact on the strategic choice of retailers and the strategic choice of retailers has the most significant impact on the strategic choice of farmers.

Given the above analysis, this paper puts forward the following policy suggestions from the three aspects of supply and marketing cooperatives, sellers and farmers:

1. Supply and marketing cooperatives level: first, strengthen the supervision and incentive mechanism. Supply and marketing cooperatives should formulate and implement stronger regulatory measures to ensure that both sellers and farmers can actively participate in the recycling of waste electrical appliances and electronic products. At the same time, incentives reward sellers and farmers who do well in recovery. Second, the construction of an efficient recycling system. Invest in and develop advanced WEEE recycling facilities to improve recycling efficiency. This includes the establishment of modern processing centers and adopting green technologies to reduce the adverse impact on the environment. Third, cooperation and information sharing. Establish cooperative relationships with relevant departments and stakeholders to realize information sharing. Sharing information about recycling processes, market trends, and technological innovations helps to improve transparency and efficiency across the system.

2. Sales business level: first, actively undertake social responsibility. Formulate and implement the strategy of actively undertaking the recycling of WEEE, and integrate environmental social responsibility into the business development plan. This helps to improve the corporate image and attract more consumer recognition. Second, to establish cooperative relations with farmers. Establish close cooperation with farmers, provide technical support, training, and necessary resources, and jointly promote the recycling of WEEE. Such a collaboration will help to build a more stable and sustainable recycling system. Third, to invest in research and development and innovation. Invest in research and development to promote sustainable recycling technologies of WEEE. For example, using digital technology to reduce costs and improve the recovery efficiency, thus increasing the enthusiasm of sellers to participate.

3. Farmers’ level: First, strengthen environmental protection awareness training. Implement the information publicity and training plan for recycling WEEE in rural areas to improve farmers’ awareness of environmental protection. This can be carried out by holding information sessions and distributing publicity materials. The second is to provide economic incentives. Formulate incentive policies, such as giving certain economic rewards or preferential conditions to farmers, to encourage them to actively participate in the recycling activities of waste electrical appliances and electronic products. Third, simplify the recycling process. Simplify the recycling process and lower the threshold for farmers to participate. This can include providing convenient recycling points and simplifying recycling procedures, making it easier for farmers to participate in recycling activities.

Research limitations and future direction

This paper constructs the evolutionary game model of supply and marketing cooperatives, sellers, and farmers. In addition, it studies the influence of different influencing factors on each subject through simulation. However, the recycling of WEEE in rural areas is still in its initial stage, and the improvement of the recycling system may introduce unconsidered factors, which may limit the exogenous variables of the model. In the simulation of the WEEE recycling system, the parameter setting is limited by the system complexity and the external influence, which may lead to the simulation results and the actual deviation.

With the development of the electrical and electronic industry, more influencing factors should be included as comprehensively as possible in the study of rural WEEE recycling in the future. Secondly, in the process of model variable assignment, real industrial data should be used as far as possible, and at the same time, other industrial recycling research paradigms should be used for reference, and the reality of WEEE should be combined, to make the future research on WEEE recycling more convincing.

Author contributions

Y.G. (First Author):Conceptualization, Methodology, Software, Investigation, Formal Analysis, Writing—Original Draft; X.H. (Corresponding Author):Data Curation, Writing—Original Draft, Author Conceptualization, Resources, Supervision, Writing—Review & Editing. D.X.: Visualization, Investigation, Visualization, Writing—Review & Editing; C.L.: Resources, Supervision; Software, Validation.

Funding

General Project of National Social Science Foundation (23BJL010); General Project of Chongqing Social Science Planning (2022NDYB69); Key Science and Technology Project of Chongqing Municipal Education Commission (KJZD-K202300508).

Data availability

The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.Corresponding author Xiao Huang. E-mail address: 2022210515095@stu.cqnu.edu.cn.

Declarations

Competing interests

The authors declare no competing interests.