Publication detail

Less is more: Optimising the biocementation of coastal sands by reducing influent urea through response surface method

Ashraf, M.S., Hassan Shah, M.U., Bokhari, A., Hasan, M.

Original Title

Less is more: Optimising the biocementation of coastal sands by reducing influent urea through response surface method

Type

journal article in Web of Science

Language

English

Original Abstract

The excessive effluent ammonia produced during the conventional biocementation of coastal sands by ureolytic Microbially Induced Calcite Precipitation (MICP) poses a looming threat to the marine environment. This research mitigates this threat by employing a brute force deployment of the Response Surface Method (RSM) for optimal minimisation of urea, which is the primary contributor of this effluent ammonia, to develop a sustainable MICP treatment model for the biocementation of coastal sand columns. The unconfined compressive strength (UCS) and calcium carbonate content (CCC) results of these columns, measured during their UCS and gravimetric acid washing testing, were used in this developed model for its validation and further optimisation. The biocementation solution resulting from this finally optimised MICP model used 75% lesser influent urea per gram of sand than its predecessor treatment model and still significantly improved the UCS of biocemented sand columns (from 0 kPa to 111.63 kPa). The structural analyses (XRD, FESEM) of these biocemented columns showed the adsorption of calcium carbonate and nesquehonite crystals on sand grains. This reduction in the consumption of urea significantly lowers the production of effluent ammonia during the biocementation of coastal sands. Therefore, it is suggested that this optimised MICP treatment model offers a sustainable method for strengthening coastal sands with little to no effect on the natural mosaic of their subsurface ecosystems.

Keywords

Biocementation; Calcium carbonate content; Sustainability; Unconfined compressive strength

Authors

Ashraf, M.S., Hassan Shah, M.U., Bokhari, A., Hasan, M.

Released

15. 9. 2021

Publisher

Elsevier Ltd.

Location

ELSEVIER SCI LTDTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND

ISBN

0959-6526

Periodical

Journal of Cleaner Production

Number

315

State

United Kingdom of Great Britain and Northern Ireland

Pages from

128208

Pages to

128208

Pages count

18

URL

https://www.sciencedirect.com/science/article/abs/pii/S0959652621024264?via%3Dihub

BibTex

@article{BUT172194,
  author="Syed Awais Ali Shah {Bokhari}",
  title="Less is more: Optimising the biocementation of coastal sands by reducing influent urea through response surface method",
  journal="Journal of Cleaner Production",
  year="2021",
  number="315",
  pages="128208--128208",
  doi="10.1016/j.jclepro.2021.128208",
  issn="0959-6526",
  url="https://www.sciencedirect.com/science/article/abs/pii/S0959652621024264?via%3Dihub"
}