RESUMO
Wastewater treatment plants (WWTPs) are one of the largest sources of greenhouse gas (GHG) emissions, and they are also one of the largest energy consumption industries in urban systems. With the progression of upgrading and standard-rising, WWTPs both directly and indirectly increase carbon emissions from the increased investments in facilities and usages in electricity as well as chemical agents. Here, we collected operational data from 15 WWTPs in the key control areas of the Ziya River Basin in North China and accounted for the changes in carbon performance at different technical upgrade methods. Results showed that the average carbon emission performance increased by 0.487 kg CO2/m3 after the upgrade. Carbon emissions from electricity consumption, chemical usage, biochemical process and sludge treatment accounted for 42%, 17%, 24%, and 17% of the total improvement in carbon emission performance, respectively. Reducing energy consumption, regulating chemical use and sludge comprehensive utilization are the key to carbon emission reduction. It further proposes that the development of wastewater treatment discharge standards should fully consider the comprehensive utilization of water quality classification. Regions with favorable natural conditions should make full use of their advantages by adopting economically feasible, low-energy-consuming technologies such as constructed wetlands, which offer carbon sequestration and landscaping benefits. This study provides guidance on the selection of technological pathways for pollution reduction and carbon mitigation in the wastewater treatment industry and on achieving sustainable water resource utilization.
Assuntos
Carbono , Rios , Águas Residuárias , China , Rios/química , Águas Residuárias/química , Carbono/análise , Eliminação de Resíduos Líquidos/métodos , Gases de Efeito Estufa/análise , Purificação da Água/métodosRESUMO
With the increasing problems of global warming, ecological damage, and excessive consumption of resources, a greater number of countries are focusing on corporate carbon performance and carbon emissions. Enterprises can save energy and reduce emissions through green innovation, which will improve the efficiency of carbon use and contribute to higher levels of corporate carbon performance. Meanwhile, effective corporate governance can improve enterprise performance, while internal governance systems can affect enterprise carbon performance. This study aims to reveal how the green innovation affect carbon performance of enterprises and the role of internal governance. So this study utilizes the data of China's A-share listed manufacturing companies from 2010 to 2020 to examine the impact of green innovation on corporate carbon performance through a fixed-effects model, and to examine the impact of corporate internal governance structure on green innovation and carbon performance through a moderating-effects model. The data used in this study are mainly from China Securities Market and Accounting Research Database (CSMAR) and China Research Data Service Platform (CNRDS), and the robustness test is conducted by replacing the independent variables using the 2sls method. The findings indicate that green innovation has a significant contribution to enterprise performance on carbon. Ownership concentration and executive political connections negatively moderated the relationship between green innovation and carbon performance. Director compensation positively moderates the relationship between green innovation and carbon performance. This research provides a theoretical groundwork for future studies on green innovation and carbon performance, and its findings are instructive for both the introduction of government policies and the restructuring of internal corporate governance.
RESUMO
Executives' carbon cognition (ECC) is an important driving factor for enterprises to achieve carbon performance (CP) through low-carbon actions, but the existing research has not explored the mechanism between them. Based on the data of 440 Chinese listed companies from 2012 to 2021, we used text mining method to construct the index of ECC, and obtained noteworthy results through regression analysis. The results indicated that ECC has a significant positive impact on corporate low-carbon actions (CLA); CLA has a significant positive impact on CP; CLA plays a mediating role in the relationship between ECC and CP; in addition, firm size negatively moderates the positive impact of ECC on CLA; firm size negatively moderates the mediating effect of CLA on the relationship between ECC and CP. The research conclusions deepen the understanding of the relationship between ECC and CP in the context of carbon neutrality era, and provide theoretical guidance for guiding companies to actively implement low-carbon actions. At the same time, this study introduces the text mining method into the research of ECC, which provides a reference for future research in this field.