Separation Technology for Solid Waste Treatment and Recycling

Dear Colleagues,

With the development of industrialization and the improvement of people's economic standing, more and more wastes are generated in our lives and production process. But almost all solid waste has specific resources, and even contains very important rare resources, such as rare metals, precious metals, and crude oil. At the same time, solid waste treatment can also convert wastes into resources, such as converting organic waste into industrial resources such as methane, acetic acid, and methanol. Therefore, researchers strive to recycle these valuable resources during the solid waste treatment process, with separation technologies becoming the main means of recycling resources from solid waste. Meanwhile, many solid wastes contain toxic substances, such as dioxins, polychlorinated biphenyls, PFOS, heavy metals, etc. Toxic substances in solid waste can be separated using separation technologies to make these solid wastes harmless. There are also some solid wastes which require specific separation techniques in the pre-treatment process, such as sludge dewatering.

For this Special Issue, we are inviting high-quality original articles focusing both on state-of-the-art approaches and newly developed separation technologies for solid waste treatment and recycling. Some areas of interests will cover, but are not limited to:

• Recycling valuable resources from solid waste using separation techniques;
• Recycling resources generated during waste treatment processes via purification;
• Removal of toxic substances from solid waste via separation;
• Pre-treatment of solid waste via separation.

Because harmful liquids and gases in containers are classified as hazardous wastes, papers on the treatment of such liquid and gas hazardous wastes using separation technologies are also welcome.

Dr. Ying Huang
Dr. Kazuyuki Oshita
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Separations is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• solid waste
• recycling
• rare metals
• crude oil
• separation techniques

Title: Simulation on Simultaneous Seperation of High-purity Methane and Carbon dioxide from Biogas by Vaccum Pressure Swing Adsorption Process
Authors: Dong Zhang
Affiliation: Shanghai Municipal Design Institute
Abstract: -

Title: Investigation of suitable polymer flocculants for the harvesting of Chlorella sp.
Authors: Ryosuke Homma, Akiho Yonezawa, Tao Wang, Tetsuya Yamamoto, Masaki Takaoka, Hideki Kanda and Kazuyuki Oshita
Affiliation: a:Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, C-cluster, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto 615-8540, Japan b:Department of Chemical Systems Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
Abstract: -

Title: Evaluating bioflocculation harvesting of freshwater and marine microalgae using exopolysaccharides (EPS) from Klebsiella sp.
Authors: Yicheng Yuan; Jingxuan Lu; Quan Wang
Affiliation: Department of Environmental Engineering, College of Ecology and the Environment, Nanjing Forestry University, Nanjing, China.
Abstract: The rising global energy demand and environmental concerns associated with fossil fuels have intensified interest in sustainable biofuel sources, with microalgae emerging as a viable candidate due to their high biomass yield and efficient CO₂ conversion. However, the economic feasibility of microalgal biofuels is currently challenged by costly harvesting processes. This study investigates the use of exopolysaccharides (EPS) derived from Klebsiella sp. as an environmentally friendly bioflocculant for harvesting two microalgae species: R. subcapitata and D. salina. Comparative flocculation experiments revealed that Klebsiella EPS promotes efficient aggregation in R. subcapitata, achieving over 90% flocculation efficiency, while performance with D. salina was impacted by high salinity, which reduced charge neutralization and bridging effects. Structural analyses using FTIR, 3D-EEM, CLSM, and XPS elucidated the EPS composition, underscoring the roles of polysaccharides and proteins in facilitating microalgal aggregation. The findings indicate that Klebsiella EPS offers a sustainable alternative to chemical flocculants, supporting eco-friendly biofuel production and potential applications in wastewater treatment. This approach provides insights into optimizing EPS-based flocculation for diverse environmental conditions, paving the way for more sustainable biomass recovery practices.