Utilization of carbide sludge and urine for sustainable biocement production

doi:10.1016/j.jece.2022.107443

Journal of Environmental Chemical Engineering

Volume 10, Issue 3, June 2022, 107443

https://doi.org/10.1016/j.jece.2022.107443 Get rights and content

Highlights

•
Soluble calcium ions can be derived from carbide sludge for biocement production.
•
Urine serves as the sole growth medium for urease producing bacteria cultivation.
•
Urine-contained urea is a substitute of commercial urea for biocementation.
•
The ingredients from carbide sludge and urine can be used to produce biocement.

Abstract

Biocement is an emerging construction material via the microbially induced calcite precipitation (MICP) process for soil improvement, which could be produced using waste materials at ambient temperature. This paper investigates the possibility to produce sustainable biocement using industrial waste carbide sludge and urine. Urine was used as the growth medium for the cultivation of urease-producing bacteria (UPB). It was also used to provide urea to activate the MICP procedure together with the soluble calcium ions from carbide sludge and UPB to form calcium carbonate precipitation. The UPB produced in this way was urease active, capable of hydrolyzing urine-contained urea for calcium carbonate precipitation. The sand treated with biocement using the above ingredients achieved an unconfined compression strength of 1.2–1.7 MPa at 7.3–7.7% calcium carbonate content, whereas the permeability was reduced by two orders of magnitude. These results show the potential to use carbide sludge and urine for sustainable production of biocement.

Graphical Abstract

Introduction

Biocement is a new cementitious product that can be used as a substitute for cement for soil improvement. It is made through microbial processes such as the microbially induced calcite precipitation (MICP) process and has been demonstrated to be effective in increasing the strength and reducing the permeability of soil [12], [14], [18], [30], [9]. During the MICP process, urease producing bacteria (UPB) decompose the urea to form carbonate ions (Eq. 1), where calcium carbonate precipitation occurs in the presence of soluble calcium ions (Eq. 2) [18], [31]. When this process is taking place inside soil, the calcium carbonate generated will bond the soil particles or fill the pores between soil particles to improve the strength and reduce the permeability.CO(NH₂)₂ + 2 H₂O → 2NH₄⁺ + CO₃²⁻Ca²⁺ + CO₃²⁻→ CaCO₃ (↓)

UPB, urea, and soluble calcium ions are the three main components of biocement. The cost of biocement can be reduced if waste materials can be used for making any of the three components. A cheaper UPB enrichment method was developed by Yang et al. [31] to isolate and enrich UPB from activated sludge under non-sterile conditions. Urease active bacteria could also be isolated from fertile soil [2] and calcareous site [10], while the costly protein-rich yeast extract medium could be replaced by cheaper commercial milk powder or lysed activated sludge [5] to minimize the cost. Although many researchers have studied the possibility to replace urea with urine [13], [15] or find alternative calcium sources, such as calcium acetate, calcium nitrate, and calcium sulfate [1], [29], the cost is still a big obstacle of large-scale applications of MICP technique [11], [4] Therefore, making MICP technique more sustainable and cheaper to facilitate large-scale application is prevailing.

This paper aims to reduce the cost of biocement production through the use of wastes. These include the use of urine as both the only growth medium for bacteria cultivation and also a replacement of urea, and the use of carbide sludge from an acetylene production process as a soluble calcium source for sustainable production of biocement. As such, both raw materials are in theory easy to obtain and have substantial availability. For example, urine-diverting dry toilets have been established and evaluated at a municipality scale to produce agricultural fertilizers from human urine in eThekwini, South Africa, which was supported by the Bill and Melinda Gates Foundation [26], [3]. Common chemical species and substances found in human urine are listed as follows: Na⁺, K⁺, Cl^-, P, NH₄⁺ (inorganic), Urea (not exceed 0.4 M), Creatinine, Uric acid, protein (organics) [23]. It has been approved that the NH₄⁺, P, Urea, and protein [31], [5] are the main nutrients of growth medium for UPB cultivation. The method presented in this study provides a sustainable approach to use the MICP methods for soil improvement in a cost-effective manner.

Section snippets

Carbide sludge

The carbide sludge was collected from a local acetylene production industry in Singapore, which contains 30% of Ca(OH)₂ in w/w_. A total of oven-dried 100 g of carbide (greater than 30 g of Ca(OH)₂, roughly 0.4 moles of solid Ca(OH)₂) was dissolved in 1 L of 0.8 M of waste nitric acid from a local chemical plant. The mixture is well-mixed to allow complete reaction, the residue was then filtered using filter paper, leading to the obtained solution containing appropriately 0.4 M of soluble Ca²⁺.

Effect of urine and glucose addition on urease activity

Urine was used as the only growth medium for the cultivation of urease producing bacteria. During cultivation, the proliferation curve of urease producing bacteria is shown in Fig. 2. Evidently, the urease activity initially increased and then decreased along with cultivation time. The urease activity reached its peaks around 3 U/ml after 30 h of cultivation with urine only, whereas the urease activity increased to around 6 U/ml in 30 h with 5 g/L of glucose addition. It was noticed that the

Conclusion

This note discussed a method to produce sustainable biocement from wastes. By utilizing urine as the growth medium, urease producing bacteria can be enriched from activated sludge and used for subsequent biocement production. Urine was also used to replace urea for the MICP process. Calcium ions extracted from carbide sludge were also used. The effectiveness of the biocement produced using the proposed method for soil improvement was evaluated using strength and permeability tests. The UC

CRediT authorship contribution statement

Yang Yang: Conceptualization, Methodology, Formal analysis, Investigation, Data curation, Writing – original draft. Jian Chu: Conceptualization, Methodology, Validation, Resources, Writing – review & editing, Funding acquisition. Hanlong Liu: Methodology, Investigation, Validation. Liang Cheng: Conceptualization, Validation, Writing – review & editing.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

We would like to acknowledge gratefully that the study reported in this paper was supported by the Center for Urban Solutions, Nanyang Technological University, Singapore, and partially supported by Jiangsu Distinguished Professor Program and Jiangsu Province “Six Talent Peak” program (XCL-111), Jiangsu Province, China and National Natural Science Foundation of China, China (Grant No. 52108300).

References (31)

H.N. Bischel et al.
Pathogens and pharmaceuticals in source-separated urine in eThekwini, South Africa
Water Res.
(2015)
Y. Gao et al.
Calcium carbonate precipitation catalyzed by soybean urease as an improvement method for fine-grained soil
Soils Found.
(2019)
M.P. Harkes et al.
Fixation and distribution of bacterial activity in sand to induce carbonate precipitation for ground reinforcement
Ecol. Eng.
(2010)
J. Henze et al.
Microbial induced calcium carbonate precipitation at elevated pH values (> 11) using Sporosarcina pasteurii
J. Environ. Chem. Eng.
(2018)
S. Lambert et al.
Manufacturing bio-bricks using microbial induced calcium carbonate precipitation and human urine
Water Res.
(2019)
T. Ogino et al.
The formation and transformation mechanism of calcium carbonate in water
Geochim. Et Cosmochim. Acta
(1987)
Y.J. Phua et al.
Bio-cementation through controlled dissolution and recrystallization of calcium carbonate
Constr. Build. Mater.
(2018)
D. Randall et al.
Urine: the liquid gold of wastewater
J. Environ. Chem. Eng.
(2018)
F. Sun et al.
Enhanced sludge solubilization and dewaterability by synergistic effects of nitrite and freezing
Water Res.
(2018)
V. Stabnikov et al.
Formation of water-impermeable crust on sand surface using biocement
Cem. Concr. Res.
(2011)

Y. Yang et al.

Biocementation of soil using non-sterile enriched urease-producing bacteria from activated sludge

J. Clean. Prod.

(2020)

H. Akoğuz et al.

The effects of different sources of calcium in improvement of soils by microbially induced calcite precipitation (micp)

Sigma: J. Eng. Nat. Sci.

(2019)

S. Al-Thawadi et al.

Calcium carbonate crystals formation by ureolytic bacteria isolated from Australian soil and sludge

J. Adv. Sci. Eng. Res.

(2012)

L. Cheng

Innovative Ground Enhancement by Improved Microbially Induced Caco3 Precipitation Technology

(2012)

L. Cheng et al.

Selective enrichment and production of highly urease active bacteria by non-sterile (open) chemostat culture

J. Ind. Microbiol. Biotechnol.

(2013)

Cited by (13)

Soil stabilization for dunes fixation using microbially induced calcium carbonate precipitation
2023, Geoderma
Citation Excerpt :
Considering a very low dosage of spraying of biocemntation solution for wind erosion mitigation due to biocrust formation demonstrated the applicability of the method technically and economically. Hence, industrial and lower grade of materials (Gowthaman et al., 2022); industrial waste carbide sludge and urine (Yang et al., 2022); and natural materials extracted from soya been for urease activity (Maleki et al., 2016; Nikseresht, 2020; Ming-JuanCui, xxxx) can also be used to make it cost effective in desert management. Additionally, the surface strength, wind erosion potential, and thickness of the layer under different cementation solution was stated in various studies (Meng, 2021; Dagliya et al., 2022; Wang et al., 2018; Sun et al., 2018).
Climate change and desertification caused increases in sandstorms and sand movements due to the erosive force of the wind. Wind erosion is a phenomenon depending on the climatic components and surface roughness in arid and semi-arid regions responsible for health and economic loss. The phenomenon is controlled by increasing the resistance of soils using chemical, physical and biological methods. Due to the high cost and environmental issues of conventional techniques, the use of alternative green stabilization methods is inevitable. Therefore, in the present study, the effect of microbially induced calcium carbonate precipitation (MICP) on the fixation of in situ dunes in north-east of Iran was assessed. The cementation solution of 0.1–0.5 M was sprayed and evaluated after 7, 15, and 30 days. The MICP treated samples were exposed to wind tunnel for the variation of wind threshold detachment velocity (TDV) as well as other macro/micro evaluation such as unconfined compressive strength, seed germination, scanning electron microscope (SEM), and energy-dispersive X-ray spectroscope (EDX). The results suggested the critical impact of both geotechnical and geoenvironmental parameters for the selection of soil stabilizers on the fixation of dunes. It can be stated that the bio-crust formation with 0.3 M showed 123 kPa and no wind erosion potential after 30 days under the wind speed of 30 m/s. The results of the germination of H. persicum demonstrated that the contemporaneous of MICP treatment with native plants positively affect the TDV.
Dual eco-friendly application of silica fume and scoria in cement-based materials through the enhancement of microbially-induced carbonate precipitation
2022, Case Studies in Construction Materials
Citation Excerpt :
This process is more readily regulated and can generate large volumes of carbonate in a short time compared to other pathways [24]. It is also feasible to use waste materials as a culture medium or calcium source, which leads to the production of sustainable bio-cement [25]. A fundamental challenge with applying the biochemical self-healing process is the extreme and strongly alkaline concrete conditions, which prevent most bacteria from growing [26].
The partial replacement of cement or natural aggregates with industrial wastes and using microbially-induced carbonate precipitation to heal cracks are two developing methods to make more sustainable concrete. In this study, a combination of these two methods was used for the first time: Partial replacement of cement with silica fume to economically create a more favorable pH for bacterial activity and substituting natural sands partially with scoria aggregates as a novel carrier and protector for bacterial spores against the harsh and alkaline conditions of cement mortar. Preliminary investigations identified scoria as a suitable carrier since the activity of immobilized cells did not decrease considerably. Thermogravimetric and X-ray diffraction analyses confirmed that spores immobilized in scoria are capable of precipitating calcium carbonate. Different mortar mixtures were made with and without scoria immobilized healing agents and silica fume. In the absence of silica fume, adding biological healing agents to mortar mixture enhanced flexural and compressive strengths by 13% and 10%, respectively, and by 18% and 15% in the silica fume amended mortars. Healing agents lowered sorptivity coefficients by 49% when samples lacked silica fume and 63% when specimens included it. The presence of silica fume resulted in a more favorable pH environment for bacterial activity and increased precipitation of calcium carbonate, as confirmed by the scanning electron microscope. Replacing a part of cement with silica fume -as an industrial byproduct- has multiple ecological benefits: protecting the environment via waste reuse, reducing demand for energy and natural resources, decreasing greenhouse gas emissions, lowering cement manufacturing costs, and finally improving the performance of microbial carbonate precipitation leads to the production of more sustainable concrete.
Bio-Cement: A Sustainable Approach in the Construction Sector
2024, AIP Conference Proceedings
A rapid and costeffective biogrouting method for forming bio-piles considering in-situ situation
2024, Acta Geotechnica
Polypeptide additives for improving the performance of microbially induced calcite precipitation (MICP) sand consolidation
2023, Research Square
Effect of biocementation on the engineering properties of sand soils under different flow rates and treatment durations
2023, International Journal of Environmental Science and Technology

View all citing articles on Scopus

View full text

Utilization of carbide sludge and urine for sustainable biocement production

Highlights

Abstract

Graphical Abstract

Introduction

Section snippets

Carbide sludge

Effect of urine and glucose addition on urease activity

Conclusion

CRediT authorship contribution statement

Declaration of Competing Interest

Acknowledgments

Water Res.

Soils Found.

Ecol. Eng.

J. Environ. Chem. Eng.

Water Res.

Geochim. Et Cosmochim. Acta

Constr. Build. Mater.

J. Environ. Chem. Eng.

Water Res.

Cem. Concr. Res.

J. Clean. Prod.

The effects of different sources of calcium in improvement of soils by microbially induced calcite precipitation (micp)

Sigma: J. Eng. Nat. Sci.

Calcium carbonate crystals formation by ureolytic bacteria isolated from Australian soil and sludge

J. Adv. Sci. Eng. Res.

Innovative Ground Enhancement by Improved Microbially Induced Caco3 Precipitation Technology

Selective enrichment and production of highly urease active bacteria by non-sterile (open) chemostat culture

J. Ind. Microbiol. Biotechnol.