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BACKGROUND: This work is focused on phosphorus recovery from anaerobically digested organic fraction of municipal solid waste (referred to as "digestate") as a fertiliser. The main purpose was to propose and test modifications to the electrodialytic process that increase phosphorus extraction, improve the quality of the fertiliser by removing contaminants, and reduce hydraulic retention time to This article is protected by copyright. All rights reserved. allow for smaller system footprints. Strategies tested were: i) lowering the pH of the digestate suspension to below 4.5 using the electrochemical reactions and enhance phosphorus solubilisation from the waste; ii) change the configuration of the electrodialytic cell from 3-to 2-chambers; and iii) stir the sample to shorten the duration of the extraction.RESULTS: Results show that the acidification of digestate by the electrochemical reactions was effective to enhance phosphorus extraction yield. Three-chamber electrodialytic experiments enabled the removal of heavy metals from digestate, producing phosphorus-rich solutions with a low level of metals. This resulted in the production of high quality fertiliser which can be used for agricultural applications. The modification of electrodialytic cell set-up from 3-chamber to 2-chamber did not result in an increase of the phosphorus extraction yields nor did it contribute to the removal of metals from the liquid phase of digestate. The reduction of the hydraulic retention time of electrodialytic extraction of phosphorus from 16d to 9d was attained by the use of stirring and by the electrodialytic acidification.CONCLUSIONS: The increase of phosphorus recovery was accomplished. 90% of phosphorus was successfully extracted from digestate and transformed into struvite.

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In addition to the health crisis caused by the coronavirus pandemic, several countries—particularly in developing regions—faced serious additional challenges in the economic, social and environmental areas. In Brazil, one of these challenges refers to the changes in consumption caused by the lockdowns, and the environmental impacts caused by new patterns of waste generation. Against this background, this paper investigates the changes in consumption and waste generation in Brazil during the COVID-19 pandemic. It provides a technical contribution to the topic by comparing the perception of survey respondents on the amount of household waste produced before and during the pandemic, and cross-checking these with information on current aspects of policymaking, the findings suggest that the amount of some specific types of household waste has noticeably increased, challenging even more the local waste management systems. The data instrument was validated by a pre-test, prior to deployment. According to the respondents, packaging (both plastic and paper/cardboard) was the type of waste that reported the highest increase in generation during the lockdowns, which is in line with the results of increased consumption of food delivery within this period. The results also suggest that current waste management policies make Brazil ill-equipped to deal with one of the non-intended effects of the COVID-19 pandemic, which has severely impacted Latin America’s largest country.