Bacterial Carbonate Precipitation Research Articles

An Experimental Investigation on Self-Healing Concrete Made of Bacteria with Varying Doses

Abstract: The employment of carbonate-producing bacteria as a new approach to enhance the qualities of concrete has attracted a lot of interest since it is thought to be innocuous to theenvironment, natural, and maybe advantageous. This is a result of the favorable implications attached to these traits. The use of microbially induced carbonate precipitation as a remedy for several problems affecting concrete, such as fracture healing, reduction and change of porosity and permeability, and more, has been the subject of much investigation. Concrete crack healing is one of the topics that have been researched. Additionally, it has been shown that the procedure of bacterial carbonate precipitation, also known as bio deposition, contributes to the development of concrete's compressive strength. There has not yet been a thorough investigation of the research relating to the appropriate bacterial solution dose and its effect on concrete durability. This might occur as a result of the project not receiving enough time to complete it. As a result, it has been decided that an investigation will be conducted in order to determine the proper quantities of bacterial solution required for concrete. To do this, several concrete cube samples will be made using varying amounts of bacterial solution, such as 15 ml, 30 ml, 45 ml, 60 ml, and 75 ml, respectively. These quantities will be added to the appropriate moulds. This will allow you to determine the proper dosage of the bacterial solution to employ. In order to determine the optimal dosage that should be used, these various samples are also put through a battery of tests using a variety of laboratory techniques, such as the properties of materials, slump cone test, a compressive strength testing machine, an ultrasonic pulse velocity test, plate count cells, and scanning electron microscopes, Rapid Chloride Penetration Test (RCPT), Acid attack test.

The experimental performance of durability and strength to repair for micro cracks in a self-healing bacterial concrete

Carbonate-producing bacteria have sparked a lot of attention as a promising, natural, and environmentally friendly new method for improving concrete properties. Using microbial-induced carbonate precipitation to ameliorate many concrete difficulties, such as fissure repair, reduction and change of porosity and permeability, has received a lot of attention. Furthermore, bacterial carbonate precipitation (bio deposition) has been proven to improve concrete's compressive strength. Meanwhile, it appears that the study of the appropriate dosage of bacterial solution and its influence on concrete durability has been thoroughly examined. As a result, it was determined to conduct research into finding the ideal doses of bacterial solution necessary for concrete by making several concrete cube samples with different bacterial solution concentrations, such as 20 ml, 40 ml, 60 ml, 80 ml and 100 ml. Furthermore, these varied samples are examined using a variety of laboratory procedures, including the slump cone test, compressive strength test, Ultrasonic pulse velocity, platelets, Acid attack test. To determine the best dose. Bacterial concrete has been found to be superior to conventional concrete in every facet of durability. Among the several specimens used, it was discovered that bacterial concrete containing 60 ml solution is the best dosage, with the strength being stable or decreasing after that.

Effect of Bacterial Carbonate Precipitation on the Durability of Concrete Specimens Exposed to High Temperatures

Effect of Bacterial Carbonate Precipitation on the Durability of Concrete Specimens Exposed to High Temperatures

Integrated application of bacterial carbonate precipitation and silicon nanoparticles enhances productivity, physiological attributes, and antioxidant defenses of wheat (Triticum aestivum L.) under semi-arid conditions.

The use of calcium carbonate-precipitating bacteria (CCPB) has become a well-established ground-improvement technique. However, the effect of the interaction of CCPB with nanoparticles (NPs) on plant performance is still meager. In this study, we aimed at evaluating the role of CCPB and/or silicon NPs (Si-NPs) on the growth, physio-biochemical traits, and antioxidative defense of wheat (Triticum aestivum L.) under semi-arid environmental conditions. A 2-year pot experiment was carried out to determine the improvement of the sandy soil inoculated with CCPB and the foliar application of Si-NPs on wheat plants. We tested the following treatments: spraying plants with 1.0 or 1.5 mM Si-NPs (control = 0 mM Si-NPs), soil inoculated with Bacillus lichenforms (MA16), Bacillus megaterium (MA27), or Bacillus subtilis (MA34), and the interaction of individual Bacillus species with Si-NPs. Our results showed that soil inoculation with any of the three isolated CCPB and/or foliar application of Si-NPs at the rates of 1.0 or 1.5 mM significantly improved (p ≤ 0.05) the physiological and biochemical attributes as well as the enzymatic antioxidant activities of wheat plants. Therefore, the combined treatments of CCPB + Si-NPs were more effective in enhancing physio-biochemical characteristics and enzymatic antioxidant activities than the individual treatments of CCPB or Si-NPs, thus achieving the best performance in the treatment of MA34 + 1.5 mM Si-NPs. Our results demonstrated that the co-application of CCPB and Si-NPs, particularly MA34 + 1.5 mM Si-NPs, considerably activated the antioxidant defense system to mitigate the adverse effects of oxidative stress, thus increasing tolerance and enhancing the production of wheat plants in sandy soils under semi-arid environmental conditions.

Bacterial Carbonate Precipitation Using Active Metabolic Pathway to Repair Mortar Cracks.

A study was conducted to check the efficacy of microbial pathways for calcite precipitation to heal pre-existing cracks in mortar. In this experiment, realistic cracks of varying widths were induced on a mortar sample. Different repair methods were applied to a total of 22 mortar samples. Twelve cracked mortar samples with average crack widths ranging from 0.29 to 1.08 mm were subjected to biodeposition treatment using calcium lactate as a food source. The remaining ten samples were split into two groups: five cracked mortar samples were exclusively exposed to the bacterial solution, while the remaining five samples were immersed in distilled water. Digital image processing was used to extract the crack characteristics before and after the repair application. During several repair cycles, image processing was used to track healing. Further, these repaired mortar samples underwent examination for water permeability, ultra-sonic examination, and examination for recovered compressive strength. A forensic examination of the healing product in terms of morphology and elemental composition was conducted using RAMAN, XRD, SEM-EDS, and TGA. The water permeability of the repaired mortar sample using biodeposition with Ca-lactate was dramatically reduced, but samples treated with bacterial solution and distilled water did not exhibit any significant reduction. Complete crack healing was observed when using Ca-lactate as a food source for microbial repair. The forensic analysis confirmed the presence of calcite in healing precipitates

Biomineralisation performance of bacteria isolated from a landfill in China.

We report an investigation of microbially induced carbonate precipitation by seven indigenous bacteria isolated from a landfill in China. Bacterial strains were cultured in a medium supplemented with 25 mmol/L calcium chloride and 333 mmol/L urea. The experiments were carried out at 30 °C for 7 days with agitation by a shaking table at 130 r/min. Scanning electron microscopic and X-ray diffraction analyses showed variations in calcium carbonate polymorphs and mineral composition induced by all bacterial strains. The amount of carbonate precipitation was quantified by titration. The amount of carbonate precipitated in the medium varied among isolates, with the lowest being Bacillus aerius rawirorabr15 (LC092833) precipitating around 1.5 times more carbonate per unit volume than the abiotic (blank) solution. Pseudomonas nitroreducens szh_asesj15 (LC090854) was found to be the most efficient, precipitating 3.2 times more carbonate than the abiotic solution. Our results indicate that bacterial carbonate precipitation occurred through ureolysis and suggest that variations in carbonate crystal polymorphs and rates of precipitation were driven by strain-specific differences in urease expression and response to the alkaline environment. These results and the method applied provide benchmarking and screening data for assessing the bioremediation potential of indigenous bacteria for containment of contaminants in landfills.

Healing cement mortar by immobilization of bacteria in biochar: An integrated approach of self-healing and carbon sequestration

Self-healing of cracks in concrete by bacterial carbonate precipitation is an effective mechanism to ensure better serviceability of civil infrastructure. This study explores biochar, derived from wood waste, as carrier for carbonate precipitating bacteria spores in cement mortar to seal cracks, and recover strength and permeability of healed samples. Superabsorbent polymer (SAP) and polypropylene microfibers (PP) were added to ensure moisture availability to bacteria and control crack propagation during damage of mortar. Samples were damaged by pre-loading to different levels – 50% and 70% of peak strength at 14-day. Experimental results show that biochar immobilized spores combined with SAP and PP precipitate copious amount of calcium carbonate, which completely sealed cracks up to 700 μm. This mix also showed highest recovery of impermeability and strength under both levels of preloading. Improvement in strength by 38% and reduction in water penetration and absorption by 65% and 70% was observed by immobilization of spores in biochar, compared to directly added spores. From comparison between samples, it was found that inclusion of PP fiber contributed to recovery of strength and impermeability, while SAP ensured higher precipitation of bacterial induced carbonate precipitation. The study suggests that spores immobilized in biochar has potential to offer excellent self-healing in cement composites. Using biochar is also a carbon sequestration strategy because of high volume of stable carbon stored in biochar particles during pyrolysis. Therefore, the proposed material combination would offer carbon storage in buildings, while also promoting waste recycling.

Bacterial carbonate precipitation improves water absorption of interlocking compressed earth block (ICEB)

Interlocking compressed earth blocks (ICEB) are soil based blocks that allows for mortarless construction. The addition of many alternative materials into interlocking block in order to improve the durability has been reported. However there are currently lack of report and evidence on the application of biocalcification or microbiologically induced calcite precipitation (MICP) in improving the engineering properties of ICEB. This paper evaluate the effect of UB in improving the water absorption properties of ICEB. This paper also provide the results on SEM analysis of addition of 1%, 3% and 5% UB in ICEB. The bacteria were added as partial replacement of limestone water in ICEB. The results showed the reduction of 14.72% with 5% UB on initial water absorption followed by the results for water absorption by 24-hour soaking which also indicates reduction of 14.68% with 5% UB on 28th days of testing compared to control specimen. It was expected that the reduction of water absorption was due to the plugging of pores by the bacterial calcite which prevent ingression of water in ICEB samples. Therefore this study hopes that the positive results from the UB as improving in water absorption of ICEB will lead to improve others ICEB properties and others construction materials.

A cost effective cultivation medium for biocalcification of Bacillus pasteurii KCTC 3558 and its effect on cement cubes properties

Application of carbonate precipitation induced by Bacillus pasteurii for improving some properties of cement has been reported. However, it is not yet successful in commercial scale due to the high cost of cultivation medium. This is the first report on the application of effluent from chicken manure bio-gas plant, a high protein content agricultural waste, as an alternative growth medium for carbonate precipitation by B. pasteurii KCTC3558. Urease activity of B. pasteurii KCTC3558 cultured in chicken manure effluent medium and other three standard media were examined using phenate method. The highest urease production was achieved in chicken manure effluent medium (16.756Umg−1 protein). Cost per liter of chicken manure effluent medium is up to 88.2% lower than other standard media. The most effective cultivation media was selected for carbonate precipitation study in cement cubes. Water absorption, voids, apparent density and compressive strength of cement cubes were measured according to the ASTM standard. The correlation between the increasing density and compressive strength of bacterial added cement cube was evident. The density of bacterial cement cube is 5.1% higher than control while the compressive strength of cement mixed with bacterial cells in chicken manure effluent medium increases up to 30.2% compared with control. SEM and XRD analysis also found the crystalline phase of calcium carbonate within bacterial cement which confirmed that the increasing density and compressive strength were resulted from bacterial carbonate precipitation. This study indicated that the effluent from chicken manure bio-gas plant could be used as an alternative cost effective culture medium for cultivation and biocalcification of B. pasteurii KCTC3558 in cement.

Characterization of bacterial diversity associated with calcareous deposits and drip-waters, and isolation of calcifying bacteria from two Colombian mines

Bacterial carbonate precipitation has implications in geological processes and important biotechnological applications. Bacteria capable of precipitating carbonates have been isolated from different calcium carbonate deposits (speleothems) in caves, soil, freshwater and seawater around the world. However, the diversity of bacteria from calcareous deposits in Colombia, and their ability to precipitate carbonates, remains unknown. In this study, conventional microbiological methods and molecular tools, such as temporal temperature gradient electrophoresis (TTGE), were used to assess the composition of bacterial communities associated with carbonate deposits and drip-waters from two Colombian mines. A genetic analysis of these bacterial communities revealed a similar level of diversity, based on the number of bands detected using TTGE. The dominant phylogenetic affiliations of the bacteria, determined using 16S rRNA gene sequencing, were grouped into two phyla: Proteobacteria and Firmicutes. Within these phyla, seven genera were capable of precipitating calcium carbonates: Lysinibacillus, Bacillus, Strenotophomonas, Brevibacillus, Methylobacterium, Aeromicrobium and Acinetobacter. FTIR and SEM/EDX were used to analyze calcium carbonate crystals produced by isolated Acinetobacter gyllenbergii. The results showed that rhombohedral and angular calcite crystals with sizes of 90μm were precipitated. This research provides information regarding the presence of complex bacterial communities in secondary carbonate deposits from mines and their ability to precipitate calcium carbonate from calcareous deposits of Colombian mines.

Improvement of Concrete Durability by Bacterial Carbonate Precipitation

As like humans having the ability to precipitate minerals in the form of bones and teeth continuously, even some bacteria like Bacillus pasteurii and Bacillus sphaericus can continuously precipitate calcite, called as microbiological induced calcite precipitation. The present investigation discusses on the effects of B. pasteurii and B. sphaericus on durability of concrete beams. The efficacy of the bio deposition treatment on concrete beams with bacteria, alkali, sulfate and freeze-thaw environments along with water absorption was studied. The presence of a layer of calcium carbonate and microbial biomass resulted in a decrease of permeation properties of cementation materials. This technique not only improved the concrete strength but also enhanced water impermeability through calcite precipitation, quantified by X-ray diffraction analysis. Hence this biological treatment is highly desirable and eco-friendly. The present work guarantees a biological metabolic outcome with improvement in concrete and building material technology.

Influence of biodeposition treatment on concrete durability in a sulphate environment

Bacterial carbonate precipitation, which is based on urea hydrolysis, has been used as a surface treatment technique to decrease the permeation properties of concrete. Since permeability acts as the main reason of concrete degradation in harsh environments, this study evaluates microbial surface treatment in order to prevent sulphate ions penetration. Five groups of concrete specimens were cast and cured and were then surface treated applying three different microbial suspensions employing Sporosarcina pasteurii, Bacillus subtilis and Bacillus sphaericus bacteria. Durability was assessed through the mass losses, volume changes (expansion), water absorption and compressive strength. In order to consider further permeation properties, chloride penetration of biologically treated concrete was examined by a rapid chloride permeability test (RCPT). Experimental results and a durability loss index (DLI) indicated that biological surface treatment reduces concrete degradation in sulphate environments and improves durability characteristics. Also, the RCPT results confirmed that this technique limits chloride penetration into the concrete.

PH reduction through amendment of cement mortar with silica fume enhances its biological treatment using bacterial carbonate precipitation

Biological treatment of concrete has recently been the subject of research as an environmentally friendly technique for increasing its durability. One of the drawbacks with this method is that the very high pH environment in concrete retards the activity of even the alkalophilic bacterial species used in this treatment process. In the present study, reduction of the pH in concrete by replacement of 20 % of cement with silica fume was considered as a means of enhancing the biological treatment process. For this purpose, mortar specimens not amended (normal) and amended with silica fume were subjected to bacterial treatment using Sporosarcina pasteurii ATCC 11859 cells, which produce calcium carbonate in cement mortar specimens through enzymatic hydrolysis of urea. In order to test the extent of the enhancement effect, some mortar specimens containing artificial cracks were also used in the experiments. The findings of the present study showed that the biological treatment of silica fume amended mortar specimens results in lower formation of bacterial biofilm but meaningfully higher precipitation of calcium carbonate, in the form of calcite, aragonite and vaterite, compared to normal specimens. Irrespective of the curing age and the presence or absence of artificial crack, the compressive strength of silica fume amended mortar specimens was always meaningfully higher than the corresponding value for normal mortar specimens. In further tests, the value of sorptivity coefficient for 28 days old biologically treated mortar specimens not amended and amended with silica fume was 42–48 % and 57–64 % lower, respectively, than the corresponding value determined for untreated specimens.

Non-Ureolytic Bacterial Carbonate Precipitation as a Surface Treatment Strategy on Cementitious Materials

AbstractBacterially induced CaCO3 precipitation is a general phenomenon in nature. It has been proposed as an environmentally friendly strategy for the protection of cementitious materials. This paper investigates the biochemistry of CaCO3 precipitation induced by non-ureolytic bacteria of the genus Bacillus. Different calcium sources are compared for their effectiveness in bacterial mediation of precipitation. Surface treatment using this biodeposition technique is evaluated by parameters affecting the durability of cementitious materials. Outcomes from this study reveal that the type of calcium source has a profound impact on the biochemical process and the crystal form, size, and morphology of bacterially mediated mineralization of CaCO3. An organic calcium source, particularly calcium glutamate, is beneficial for efficient CaCO3 precipitation. Bacterial surface treatment on specimens results in a decrease of more than 50% in capillary water absorption and an increase of nearly 50% in resistance to car...

Bacterial carbonate precipitation improves the durability of cementitious materials

Shortcomings of conventional surface treatments have drawn the attention to alternative techniques for the improvement of the durability of concrete. This paper reports the effects of bacterial carbonate precipitation (biodeposition) on the durability of mortar specimens with different porosity. Durability was assessed from the permeation properties and resistance towards degradation processes. The surface deposition of calcium carbonate crystals decreased the water absorption with 65 to 90% depending on the porosity of the specimens. As a consequence, the carbonation rate and chloride migration decreased by about 25–30% and 10–40% respectively. An increased resistance towards freezing and thawing was also noticed. The results obtained with the biodeposition treatment were similar as those obtained with conventional surface treatments.

Bacterial carbonate precipitation as an alternative surface treatment for concrete

Surface treatments play an important role in the protection of construction materials from the ingress of water and other deleterious substances. Due to the negative side-effects of some of the conventional techniques, bacterial induced carbonate mineralization has been proposed as a novel and environmental friendly strategy for the protection of stone and mortar. This paper reports the effects of bacterial CaCO 3 precipitation on parameters affecting the durability of concrete and mortar. Pure and mixed cultures of ureolytic bacteria were compared for their effectiveness in relation to conventional surface treatments. Bacterial deposition of a layer of calcite on the surface of the specimens resulted in a decrease of capillary water uptake and permeability towards gas. This bacterial treatment resulted in a limited change of the chromatic aspect of mortar and concrete surfaces. The type of bacterial culture and medium composition had a profound impact on CaCO 3 crystal morphology. The use of pure cultures resulted in a more pronounced decrease in uptake of water, respectively less pronounced change in the chromatic aspect, compared to the use of mixed ureolytic cultures as a paste. The results obtained with cultures of the species Bacillus sphaericus were comparable to the ones obtained with conventional water repellents.

Spherulitic Pedogenic Carbonate Nodules from the Lower Tuscaloosa; A Tool to Be Used in Paleogeochemical Exploration for Hydrocarbons?: ABSTRACT

Geochemical exploration for hydrocarbons consists primarily of sampling soils and surface sediments for anomalous concentrations of a variety of materials resulting from vertical migration of hydrocarbon-contaminated subsurface waters. In addition to traces of light hydrocarbons, the anomalous materials include gases such as radon and other contaminants from oil, as well as substances concentrated by the physico-chemical properties of the vertically migrating waters. Iron concentrations are high because of the reduced condition of these waters, calcium, magnesium, and bicarbonate ions because of the acidity of the waters. Many authors have commented on the association of spherulitic aggregates of siderite in fossil soils and sedimentary facies such as levees and overbank splays in fluvial settings. Researchers have suggested that iron may have been derived by erosion from areas of lateritic weathering and transported into the area as coatings on clay minerals or complexed with organic polymers. It has been reported and illustrated that abundant dolomite spherulites in surface profiles of outcropping sediments of a variety of ages and mineral compositions from Kuwait, all from areas of surface hydrocarbon seeps or over known subsurface accumulations. Many of the spherulites are nucleated around hydrocarbon droplets, and the significance of the distribution is clear. Itmore » is hypothesizes that the dolomite spherulites are precipitated by the action of bacteria feeding on hydrocarbons, an idea supported by the work of Lalou, which demonstrated that spheroids are common products of bacterial carbonate precipitation. The authors suggest that some, at least, spherosiderites may also be related to vertically migrating oilfield fluids. Iron, calcium, and magnesium may all be supplied by these waters, while the bacterial action apparently required for spherulitic morphologies to form in the pedologic setting may result from hydrocarbons in the same rising waters.« less