Circular economy as a challenging issue in social innovation area, more specifically with a focus on sustainable development, and in response to current global challenges regarding, warming, resource scarcity, attention to the environment as well as the presentation of an economic model aimed at eliminating the direct link between economic development and resource use, has been widely discussed by researchers, experts and policymakers as one of the world’, s trends. However, the concept of Circular economy as a macro concept is still developing. In addition, many experts have considered the explanation of the Circular economy concept to be dependent on the context of its emergence, but there is few documented research that has examined this concept in the context of innovation ecosystems. The present study tries to describe the implementation of Circular innovation ecosystem with the aim of conceptualizing the Circular economy in the innovation ecosystem using previous sources and experts ’, opinions. Therefore, this study, using a hybrid approach and through methods such as )1( systematic review aiming at extracting previous data, )2(content analysis aiming at examining the opinion of experts, presents the infrastructure, strategies, programs, and requirements for establishing a Circular innovation ecosystem. This research stands out for a general question of what is the fundamental strategies of Circular economy in implementation of Circular innovation ecosystems. The results of this research will bring achievements for a wide range of researchers, policymakers in various fields, economic activists as well as institutions in charge of sustainable development.

In the Algoland project, microalgae are used to clean water and air from industry. This is built on a long standing collaboration between research, industry and society. In this way Algoland supports the transition to a Circular economy by turning pollution into biomass and potential products. This paper evaluates the potential for microalgae as an ecosystem service in industries from a Circular economy perspective. The business model canvas was used in a workshop with stakeholders and researchers to discuss the challenges and opportunities for an industrial platform. Results showed that the established canvas model needs to be complemented by Circular models; in order to be able to include ecosystem services. In this paper a Circular canvas model is developed to be used in similar approaches.

Objective Circular business models are a good solution to the problems of current linear business models that cause excessive waste generation and resource scarcity. They also provide a good opportunity for businesses to gain a competitive advantage, obtain economic benefits and reduce environmental damage. To implement Circular economy strategies at the business level and create a framework for better design of Circular business models, the purpose of this paper is to propose a framework for identifying and classifying Circular business model patterns that align with Circular economy strategies. Methodology In this research, a qualitative method was applied. Sandelowski and Barros 7-step meta-synthesis method was used to identify Circular business models and Nickerson taxonomy development method was used to classify Circular business model patterns. Findings This study drew up a comprehensive list of 29 Circular business model patterns including their name, definition, and example(s). It also proposed a comprehensive taxonomy framework for Circular business model patterns based on the Circular economy strategies. Under this framework, 11 dimensions for classifying 29 business model patterns were identified, including patterns for 1) dematerialization, 2) consumption efficiency, 3) Circular supplies, 4) optimal production, 5) reverse and optimal logistics, 6) long-life products, 7) extending the products and parts life cycle, 8) extending materials life cycle, 9) extending resource life cycle, 10) actors of main activities in the Circular value network, and 11) facilitators of activities in the Circular value network. Conclusion First, the current research identified various types of Circular business model patterns for the development of businesses based on a Circular economy. Second, by creating a framework for classifying strategies and Circular business models, it showed how to make strategies and Circular business models attuned. The results of this study can help companies that intend to implement Circular economy strategies in their business to identify and apply appropriate Circular business models. It should be noted that the strategy of the Circular value network and the patterns of the Circular business model based on it, which indicate various methods of cooperation between the actors of the Circular value network, were introduced for the first time in the research.

Background: Circular economy is gaining global acceptability, and its practice is rather poor in Nigeria similar to other developing countries. COVID-19 pandemic has caused enormous amounts of hazardous wastes, which require special attention. The present study aimed to assess Circular economy and waste management actions during the COVID-19 pandemic in Nigeria. Methods: Data were collected using quantitative and qualitative methods and analyzed to determine the challenges of hazardous waste management in Nigeria by two notable healthcare centers in Ilorin as the cases. In total, 204 questionnaires were distributed among the staff, and 202 (99%) were returned. Results: The respondents were 102 men (50. 5%) and 100 women (49. 5%) with various disciplines, including health workers (n=104; 51. 5%), maintenance staff (n=42; 20. 8%), and cleaners/waste handlers (n=56; 27. 7%). The majority of the subjects (97%) believed that COVID-19 wastes should be segregated, while 111 subjects (55%) rated the management of personal protective equipment to be appropriate during the pandemic. Conclusion: According to the results, the implementation and enforcement of national policies regarding solid waste management are essential through the training and retraining of staff on hazardous waste management in the studied healthcare centers.

As one of the most environmentally friendly and cost-effective method, anaerobic digestion (AD) has been widely studied and developed as a conventional technology to degrade biodegradable materials and produce biogas simultaneously. Various substrate sources are used in this process such as organic fraction of municipal solid waste (MSW), waste activated sludge (WAS), animal manures, agro-industrial wastes, energy crops, micro-and macro-algae and etc. With the aim of process optimization, several publications have recently studied different configurations to integrate AD and thermochemical processes such as pyrolysis and gasification. These linking technologies seeks to optimize the use of products or by-products of thermochemical processes interchangeably. In this regard, this paper aims to review different potential pathways of feasible integration and coupling. Five hybrid pathways including biochar-amended anaerobic digestion, digestate-derived biochar and hydrochar, anaerobic digestion of aqueous phase liquid derived from pyrolysis and gasification of digestate were reviewed and their schematic diagram were presented. Despite several studies to combine AD with thermochemical valorization processes, further studies at the industrial scale are needed to prove the energy efficiency and economic viability of these coupling pathways.

The Social Accounting Matrix (SAM) and its related models were designed to circumvent many restrictions inherent in the National Accounting practices. The goal was quantitative and simultaneous analysis of economics and social problems facing many of developing countries. Iran was the first country to adopt this accounting system. In the fifth plan of Iranian economy in 1973, the senior consultant from the International Labor Organization (ILO)proposed guideline for Iranian planners. The Iranian experience was carefully expanded to include other countries of the world by the same organization. The result of this experience in Iran was numerous books and articles that were published in internationally reputed journals.The debate that followed paved the way for development of a system of national account with a domestic flavor. Two of the main results of these intellectual challenges were the complete revision of the System of National Accounts of 1968 in which the importance of the role of meso level accounting, and the applications of Theory of General Equilibrium were recognized. While the Iranian experience had a tremendous effect at the international level, in Iran, it was forgotten by the academia for over two decades.The design of meso level accounting system in the form of social accounting matrix is the second experiment in Iran which is based on the experience of other countries and United Nation System of National Accounts (1993). The SAM for Iran is presented in three levels of aggregation: The Macro SAM, which has 10 rows and columns, The Meso SAM which has 33 rows and columns, and finally the Micro SAM which has 94 rows and columns. In this article the Circular flow of Iranian economy for 1996 based on Meso SAM is presented.