Alkaline and acid solubilisation of waste activated sludge

The influence of acidic and alkaline conditions on the solubilisation process of waste activated sludge (WAS) was investigated using HCl and NaOH at pH 2, 10, 11 and 12. The rise in concentration of solubilised compounds, the influence of reaction time, and the influence of the concentration of tota...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Tales Abreu Tavares de Sousa, Fernanda Patrício do Monte, José Vanderley do Nascimento Silva, Wilton Silva Lopes, Valderi Duarte Leite, Jules B. van Lier, José Tavares de Sousa
Formato:	article
Lenguaje:	EN
Publicado:	IWA Publishing 2021
Materias:	alkaline solubilisation chemical solubilisation pre-treatment of was sludge hydrolysis Environmental technology. Sanitary engineering TD1-1066
Acceso en línea:	https://doaj.org/article/d9d0374fa0744f5fb0867606788210d6
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:d9d0374fa0744f5fb0867606788210d6
record_format	dspace
spelling	oai:doaj.org-article:d9d0374fa0744f5fb0867606788210d62021-11-06T11:09:49ZAlkaline and acid solubilisation of waste activated sludge0273-12231996-973210.2166/wst.2021.179https://doaj.org/article/d9d0374fa0744f5fb0867606788210d62021-06-01T00:00:00Zhttp://wst.iwaponline.com/content/83/12/2980https://doaj.org/toc/0273-1223https://doaj.org/toc/1996-9732The influence of acidic and alkaline conditions on the solubilisation process of waste activated sludge (WAS) was investigated using HCl and NaOH at pH 2, 10, 11 and 12. The rise in concentration of solubilised compounds, the influence of reaction time, and the influence of the concentration of total solids (TS) during the solubilisation process were determined. Physical and chemical tests demonstrated that pre-treatment provided a release of compounds from the sludge floc matrix into the soluble fraction, characterising the solubilisation process. The highest degree of WAS solubilisation was observed when a pH of 12 was applied. Although largest effects were already attained after 0.25 h, WAS solubilisation continued reaching an increase in total dissolved solids by a factor 10.4 after 720 hrs. Under these conditions, the dissolved organic carbon (DOC), proteins, and carbohydrates resulted in releases up to 15, 40 and 41 times, respectively; phosphorus increased 5.7 times. Results indicate that by applying alkaline pre-treatment, higher TS concentrations can be treated per reactor volume compared to non-pre-treated WAS. Aerobic and anaerobic biodegradability tests showed increased bioconversion potentials in full-scale treatment plants. The respirometry tests ratify the improvement in solubilisation, with O2 consumption rates increasing 1.4 times, concomitant with an additional 261 mg·L−1 of the COD used, which represents 90% bioconversion of waste activated sludge. Biomethanisation test indicated an increase of 3.6 times relative to the blank. HIGHLIGHTS Increased biodegradability of sludge identified by respirometric test.; Increased applicable sludge loading rates per reactor volume.; Increased degree of depolymerisation, characterised by the release of COD, TKN, phosphorus, protein, and carbohydrate in soluble fraction.; The alkaline process significantly favours the solubilisation of microbial aggregates over the acid process.;Tales Abreu Tavares de SousaFernanda Patrício do MonteJosé Vanderley do Nascimento SilvaWilton Silva LopesValderi Duarte LeiteJules B. van LierJosé Tavares de SousaIWA Publishingarticlealkaline solubilisationchemical solubilisationpre-treatment of wassludge hydrolysisEnvironmental technology. Sanitary engineeringTD1-1066ENWater Science and Technology, Vol 83, Iss 12, Pp 2980-2996 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	alkaline solubilisation chemical solubilisation pre-treatment of was sludge hydrolysis Environmental technology. Sanitary engineering TD1-1066
spellingShingle	alkaline solubilisation chemical solubilisation pre-treatment of was sludge hydrolysis Environmental technology. Sanitary engineering TD1-1066 Tales Abreu Tavares de Sousa Fernanda Patrício do Monte José Vanderley do Nascimento Silva Wilton Silva Lopes Valderi Duarte Leite Jules B. van Lier José Tavares de Sousa Alkaline and acid solubilisation of waste activated sludge
description	The influence of acidic and alkaline conditions on the solubilisation process of waste activated sludge (WAS) was investigated using HCl and NaOH at pH 2, 10, 11 and 12. The rise in concentration of solubilised compounds, the influence of reaction time, and the influence of the concentration of total solids (TS) during the solubilisation process were determined. Physical and chemical tests demonstrated that pre-treatment provided a release of compounds from the sludge floc matrix into the soluble fraction, characterising the solubilisation process. The highest degree of WAS solubilisation was observed when a pH of 12 was applied. Although largest effects were already attained after 0.25 h, WAS solubilisation continued reaching an increase in total dissolved solids by a factor 10.4 after 720 hrs. Under these conditions, the dissolved organic carbon (DOC), proteins, and carbohydrates resulted in releases up to 15, 40 and 41 times, respectively; phosphorus increased 5.7 times. Results indicate that by applying alkaline pre-treatment, higher TS concentrations can be treated per reactor volume compared to non-pre-treated WAS. Aerobic and anaerobic biodegradability tests showed increased bioconversion potentials in full-scale treatment plants. The respirometry tests ratify the improvement in solubilisation, with O2 consumption rates increasing 1.4 times, concomitant with an additional 261 mg·L−1 of the COD used, which represents 90% bioconversion of waste activated sludge. Biomethanisation test indicated an increase of 3.6 times relative to the blank. HIGHLIGHTS Increased biodegradability of sludge identified by respirometric test.; Increased applicable sludge loading rates per reactor volume.; Increased degree of depolymerisation, characterised by the release of COD, TKN, phosphorus, protein, and carbohydrate in soluble fraction.; The alkaline process significantly favours the solubilisation of microbial aggregates over the acid process.;
format	article
author	Tales Abreu Tavares de Sousa Fernanda Patrício do Monte José Vanderley do Nascimento Silva Wilton Silva Lopes Valderi Duarte Leite Jules B. van Lier José Tavares de Sousa
author_facet	Tales Abreu Tavares de Sousa Fernanda Patrício do Monte José Vanderley do Nascimento Silva Wilton Silva Lopes Valderi Duarte Leite Jules B. van Lier José Tavares de Sousa
author_sort	Tales Abreu Tavares de Sousa
title	Alkaline and acid solubilisation of waste activated sludge
title_short	Alkaline and acid solubilisation of waste activated sludge
title_full	Alkaline and acid solubilisation of waste activated sludge
title_fullStr	Alkaline and acid solubilisation of waste activated sludge
title_full_unstemmed	Alkaline and acid solubilisation of waste activated sludge
title_sort	alkaline and acid solubilisation of waste activated sludge
publisher	IWA Publishing
publishDate	2021
url	https://doaj.org/article/d9d0374fa0744f5fb0867606788210d6
work_keys_str_mv	AT talesabreutavaresdesousa alkalineandacidsolubilisationofwasteactivatedsludge AT fernandapatriciodomonte alkalineandacidsolubilisationofwasteactivatedsludge AT josevanderleydonascimentosilva alkalineandacidsolubilisationofwasteactivatedsludge AT wiltonsilvalopes alkalineandacidsolubilisationofwasteactivatedsludge AT valderiduarteleite alkalineandacidsolubilisationofwasteactivatedsludge AT julesbvanlier alkalineandacidsolubilisationofwasteactivatedsludge AT josetavaresdesousa alkalineandacidsolubilisationofwasteactivatedsludge
_version_	1718443762978390016

Alkaline and acid solubilisation of waste activated sludge

Ejemplares similares