Electrocoagulation sludge valorization : a review
|Author:||Rajaniemi, Kyösti1; Tuomikoski, Sari1; Lassi, Ulla1|
1Research Unit of Sustainable Chemistry, University of Oulu, P.O. Box 4300, FI-90014 Oulu, Finland
|Online Access:||PDF Full Text (PDF, 0.8 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2021122262923
Multidisciplinary Digital Publishing Institute,
|Publish Date:|| 2021-12-22
In the field of electrocoagulation (EC), various studies on pollutant removal and on the use of different EC technologies have already been made. An EC process generates sludge, which is considered waste, resulting in increased operational costs that come from waste disposal. Sludge contains valuable materials, such as the nutrients or metals removed during water purification, along with metals, such as aluminum or iron, which come from the electrodes used in an EC system. Based on the principles of circular economy or based on existing legislations, reducing the production of valuable wastes, and increasing the valorization rate of as many materials as possible are important endeavors. This study is mainly a review of the existing sludge valorization studies. This review highlights the valorization of sludge as a fertilizer (mainly as struvite), pigment, construction material (mainly as blocks), adsorbent, and catalyst. While it has already been found that EC sludge is valorizable, more studies on EC sludge valorization and on the quality of sludge produced from the effluent of EC processes are warranted.
|Type of Publication:||
A2 Review article in a scientific journal
|Field of Science:||
116 Chemical sciences
Kyösti Rajaniemi acknowledges the funding support extended by the Erkki Paasikivi Foundation, Maa- ja Vesitekniikan tuki ry and Tauno Tönning Foundation. This work was conducted under the auspices of the Waterpro (ERDF project number: A74635, funded by the European Union, European Regional Development Fund, Leverage from the EU Central and Ostrobothnia Regional Council).
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).