PreprintArticleVersion 2Preserved in Portico This version is not peer-reviewed
Specification and Classification of Pelletised Dried Sewage Sludge: Identifying its Key Properties as a Renewable Material for Enabling Environmentally Non-harmful Energy Utilisation
Version 1
: Received: 18 October 2022 / Approved: 19 October 2022 / Online: 19 October 2022 (07:59:51 CEST)
Version 2
: Received: 28 October 2022 / Approved: 31 October 2022 / Online: 31 October 2022 (01:25:54 CET)
Mislej, V.; Novosel, B. Specification and Classification of Pelletised Dried Sewage Sludge: Identifying Its Key Properties as a Renewable Material for Enabling Environmentally Non-Harmful Energy Utilisation. Sustainability2022, 14, 14836.
Mislej, V.; Novosel, B. Specification and Classification of Pelletised Dried Sewage Sludge: Identifying Its Key Properties as a Renewable Material for Enabling Environmentally Non-Harmful Energy Utilisation. Sustainability 2022, 14, 14836.
Mislej, V.; Novosel, B. Specification and Classification of Pelletised Dried Sewage Sludge: Identifying Its Key Properties as a Renewable Material for Enabling Environmentally Non-Harmful Energy Utilisation. Sustainability2022, 14, 14836.
Mislej, V.; Novosel, B. Specification and Classification of Pelletised Dried Sewage Sludge: Identifying Its Key Properties as a Renewable Material for Enabling Environmentally Non-Harmful Energy Utilisation. Sustainability 2022, 14, 14836.
Abstract
Renewable active sludge is a smart material for wastewater treatment and the protection of surface water bodies. The generated pellets (dried and pelletised dehydrated anaerobically stabilised excess sludge) are produced in a quantity of 31.4 g ± 5.6 g dry matter (DM) per one Population equivalent (PE) calculated to COD (PECOD) in one day. As pellets are combustible material, their energy utilisation must reach sustainable development goals (SDGs) - a bridge must be created between »treated sewage sludge as the tool to remove pollutants and nutrients from wastewater« and »preparation of the valuable material as a solid recovered fuel (SRF) that meets customer-specific requirements«. Technical Report CEN/TR 15508 and Technical Standard EN ISO 21640 set up methods for specifying and classifying pellets as an SRF. In the last eleven years (2010 – 2021), pellets' net calorific value (NCV) is 13.0 ± 0.7 MJ kg-1 as received (ar). In 2021, the 80th percentile of the Hg/NCV ratio was 0.079 mg Hg MJ-1. In 2010 – 2021, the annual amount of Hg transferred to stakeholders reduced by 64.3 % m/m - from 10.1 kg to 3.67 kg. The halogen contents of the pellets do not threaten corrosion to the incineration facility. Stable pellets' energy potential and perspective ash composition for critical raw materials recovery qualify pellets as a specific waste stream and a renewable material for SRF production.
Keywords
alternative solid recovered fuel; classification; pelletised sewage sludge; pollution prevention; renewable material; sustainable energy production
Subject
Engineering, Energy and Fuel Technology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Received:
31 October 2022
Commenter:
Vesna Mislej
Commenter's Conflict of Interests:
Author
Comment:
Dear Sir/Madam.
The first revised version of the original article is ready. The revisors' comments regarding the content of the abstract, the clearness of the article's aim, the introduction of chapter 3 of the proposed article, Figure 3 and the inconsistency of the font in some parts of the article are taken into account.
Commenter: Vesna Mislej
Commenter's Conflict of Interests: Author
The first revised version of the original article is ready. The revisors' comments regarding the content of the abstract, the clearness of the article's aim, the introduction of chapter 3 of the proposed article, Figure 3 and the inconsistency of the font in some parts of the article are taken into account.