Preface

2021 International Conference on Environmental Engineering and Energy (ICEEE 2021) was held online in Wuhan, China, on November 20, 2021. ICEEE 2021 is co-sponsored by Modern International Green Culture Communication Association (MIGCCA), and the conference proceeding is published by IOP Publishing. ICEEE 2021 provides an excellent international forum for sharing knowledge and results in theory, methodology and applications of environmental engineering and energy. The conference looks for significant contributions to all major fields of environmental engineering and energy in theoretical and application aspects. The aim of the conference is to provide a platform to the global researchers and practitioners from both academia as well as industry to meet and share cutting-edge development in the fields.The ICEEE 2021 proceedings tend to collect the up-to-date, comprehensive and worldwide state-of-art knowledge on environmental engineering and energy. All of accepted papers were subjected to strict peer-reviewing by 2–5 expert reviewers. The papers have been selected for this volume because of quality and the relevance to the conference. We hope this book will not only provide the readers a broad overview of the latest research results, but also provide the readers a valuable summary and reference in these fields.COVID-19 cases were found in difference provinces, which were cluster of infection. In order to avoid virus' spreading, the organiser switched the conference to a virtual one. It was held online on November 20, 2021 via Tencent Meeting. The virtual conference consisted of Opening Speech (10 mins), Keynote Speeches (40 mins presentation + 10 mins Q&A), and Oral Presentation (15-20 mins presentation + 10 mins Q&A) and Concluding Remarks (5 mins). The number of attendees are more than expectation