Academic literature on the topic 'Bio-bricks'

Abstract The experimental work on characterization of biochar bricks as a construction material is summarized in this manuscript. This is an important topic to research due to the dearth of knowledge about biochar construction materials and their potential to reduce global warming. Biochar is a charcoal-like substance formed from organic matter decomposition in the absence of oxygen at high temperatures. The use of bio char in a range of applications will help in cutting down CO2 emissions, recycling of organic and plastic waste, and in creation of more jobs. Current applications of bio-char is limited to being used as Soil additives to promote water absorption, plaster to absorb humidity, and energy alternatives to replace fossil fuels. The present study attempts to characterize bio-char bricks for usage in construction. Two types of bio-char bricks were cast and compared to normal concrete bricks. The first set of bricks had 70% biochar and 30% cement, whereas the second set contained 45 percent biochar, 45 percent plastic, and 10% cement. The bricks were characterized using five tests: compressive strength, water absorption, hardness, flammability, and insulation value.

One of the major causes of an increase in the consumption of resources is the progress of the construction industry. Although it leads to new technologies, it heavily contributes to global warming. In this study, the use of sustainable construction materials from waste in brick production with mycelium as a binder is investigated. The ability of mycelium, the root fibers of fungi, obtained from microorganisms is used as stabilizing and binding material on bricks. Forty-eight brick specimens from six design mixes were produced with a size of 200 mm length × 90 mm width × 60 mm height. The mechanical tests conducted were compressive and flexural strength. The changes in weight were recorded against its age to monitor the progress of mycelium growth inside the brick specimens. From the test, bricks made from sawdust and rice bran with mycelium had an increase of 31.0% to 38.5% in average compressive strength compared to the non-mycelium bricks, respectively. Furthermore, the bricks with mycelium experienced an increase in both flexural strength and midpoint displacement for all types of bricks (rice bran, sawdust, and clay). These mycelium-induced bricks can reduce the use and consumption of traditional construction materials with enhanced mechanical properties.

Fired clay bio-bricks were prepared by adding eggshell as a bio-filler and flux into earthenware clay compounds via an extrusion process. In this study, the suiTab. conditions for clay bricks preparation were firing at 1000?C for a period of 5 h. Adding 20 wt% eggshell powder into the clay brick yielded good physical-mechanical-thermal properties: high compressive strength and hardness, low thermal expansion coefficient, and low water absorption. The measured compressive strength, hardness, and refractory water absorption were 7.0 MPa, 6.0 HV, and less than 15 wt%, respectively. The obtained clay brick with the eggshell powder added as shown here is potential for uses as bricks for construction and thermal insulation.

The aim of this study is to enhance the strength and the durability of adobe bricks by introducing bio-inspired stabilisers. This research was inspired by the high strength and durability of the termite mounds. The study investigates the stabiliser behind such strong natural constructions. The termite builds its mounds by incorporating a glycoprotein from its saliva to cement the sub-soil particles together. Biomimicry has been used as an approach to investigate the potential for the use of the termites’ construction stabiliser in adobe bricks. Three different glycoproteins sourced from the waste of the meat industry were identified as potential stabilisers in adobe bricks. Bovine serum albumin from cows’ blood, mucin from porcine stomach and gelatine from cold-water fish skin were the three stabilisers used in this study. A fourth stabiliser was made up of several chemicals which together aimed to mimic the termites’ saliva glycoprotein. Two soils were used to prepare adobe bricks for testing. The main soil used in this study was sourced from Devon in the UK. The second soil was sourced from Mayo neighbourhood in Khartoum, Sudan and it was only used in key tests. Adobe bricks were made and stabilised with different concentrations of these bio-inspired stabilisers. Controlled unstabilised adobe bricks were used for comparison. The bricks were tested for their unconfined compressive strength and erosion resistance. The main conclusion in this study is that, bovine serum albumin which is a glycoprotein derived from cows’ blood and considered as a by-product of the beef industry, has proved its potential to be used as stabiliser in earth construction. The use of 0.5 by weight percent of bovine serum albumin resulted in 41% and 17% increase in the compressive strength of the Sudanese and the British adobe bricks respectively. In addition, the use of 5 by weight percent of bovine serum albumin resulted in 202% and 97% increase in the compressive strength of the British and Sudanese adobe bricks respectively. Furthermore, the use of 0.1, 0.2 and 0.5 by weight percent of the bovine serum albumin resulted in 30%, 48% and 70% reduction in the erosion rate of the British adobe bricks respectively. The use of 0.5 by weight percent of the bovine serum albumin resulted in 97% reduction in the erosion rate of the Sudanese adobe bricks. The other stabilisers tested did not result in a significant improvement in unconfined compressive strength of the adobe bricks. However, the use of 0.1and 0.2 by weight percent of mucin from porcine stomach resulted in 28% and 55% reduction in the erosion rate of the British adobe bricks respectively.

The production of building materials is a significant contributor to anthropogenic greenhouse gas emissions with conventional kiln brick production being one of the most energy intensive processes. In addition, phosphorus is a resource that is required by all living organisms and is a key ingredient in many fertilisers. The demand for building materials and global natural phosphate rock (phosphorous) are increasing and decreasing respectively as urbanization increases. Naturally occurring phosphorous is expected to experience a peak in the near future after which it will be completely depleted. Urine has been identified as a potential source of phosphorous for fertiliser production as well as urea for microbial induced calcium carbonate precipitation (MICP) applications. MICP is a natural process that has the ability to produce bio-building material. Urine accounts for a small percentage of the total volume of domestic wastewater but contains a large percentage of the nutrients wastewater treatment plants (WWTP) seek to remove before they adversely affect receiving water bodies. The unprecedented rate of climate change and the associated pressures, coupled with the increased awareness around the depletion of natural resources, presents a significant challenge for which innovative and sustainable solutions are required. The reason for engaging in this project was to investigate if the urea present in human urine could be used in the natural MICP for the production of bio-bricks while at the same time recovering phosphorus from urine. Firstly, a thorough review of literature was conducted to assess current innovations pertaining to the dissertation topic. The process of bio-brick production by MICP requires a urea rich solution which could be recovered from urine. However, the urea present in urine naturally degrades and this process needs to be delayed if urine is to be used as a urea source for MICP. This was achieved by “stabilising” the urine with calcium hydroxide. Sporosarcina pasteurii (S. pasteurii) was the bacteria strain used to help drive the MICP process. The bacteria degraded the urea present in the urine to form carbonate ions which then combined with the calcium ions present in the urine solution to produce calcium carbonate. This calcium carbonate was then used as a bio-cement to glue loose sand particles together in the shape of a brick. The cementation media was made by adding calcium chloride and nutrient broth to the stabilised urine, and lowering its pH to 11.2. The purpose of adding calcium chloride was to improve the efficiency of the process since the stabilised urine did not have enough calcium ions. Ordinary sand mixed with Greywacke aggregate and inoculated with S. pasteurii bacteria was used as the media for the MICP process. Bio-brick moulds were filled with the sand mixture and sealed. The cementation media was pumped through the bio-brick mould to fill its’ pore volume. The media was retained in the moulds for a defined retention time ranging from 1-8 hours. At the end of every retention time, new cementation media was pumped through the bio-brick to fill it’s pore volume again. iv To establish an optimal starting influent calcium concentration the influent calcium concentration changed between experiments. Additionally, in subsequent experiments, the calcium concentration was raised in a stepwise manner during an experiment to establish the maximum amount the influent calcium concentration could be raised to before the microbial community experienced adverse effects. Additionally, experiments explored the effects a range of retention times had on the bio-brick system in order to establish an optimal retention time. Another experiment was set up to investigate the relationship between the number of treatments and the resultant compressive strength. The findings from the above-mentioned experiments further guided subsequent experiments which singled out and tested certain factors thought to be affecting the bio-brick system. The factors tested include after treatment washing, ionic strength, pH and calcium concentration of the influent cementation media. Possible alternative nutrient medias (ANMs) were also investigated for a cheaper alternative to the laboratory grade growth media used to grow the bacteria. Lastly, an integrated system that produced both fertilisers and bio-bricks was developed. Its basic economics of raw material inputs and outputs were used to assess the financial implications of the proposed system, and the social and policy barriers likely to affect the implementation of an integrated urine treatment system were examined. Urine treated with calcium hydroxide offers a urea-rich solution that can be used for MICP processes. This resulted in the worlds’ first bio-brick “grown” from human urine. The starting influent calcium concentration reached a maximum of 0.09 M before adverse effects to the microbial community were experienced. Furthermore, in terms of a stepwise increase during the treatment cycle, the influent calcium concentration could be raised to 0.12 M without any adverse bacteria effects. The minimum retention time the bio-brick system could withstand was 2 hours which allowed the treatment cycle to be completed in a shorter time. The highest compressive strength obtained was equal to 2.7 MPa. To produce this strength about 31.2 L of stabilised urine was used. The relationship between the number of treatments and the compressive strength showed that an increase in the number of treatments increased the compressive strength. Both the pH and ionic strength of the urine were identified to have an inhibiting effect on the ureolytic activity and MICP process. Additionally, using an influent cementation media with an optimal pH for urea hydrolysis, improved the bacteria’s ability to operate at higher ionic strengths. However, when the stabilised urine was stored, urea hydrolysis occurred earlier likely because of external contamination by naturally occurring bacteria in the lab. LML (Lactose mother liquor) was identified as alternative growth media for S. pasteurii growth which could reduce raw material costs considerably. The bio-brick production process was found to be more cost-effective if it was incorporated into the integrated urine treatment process system. The integrated system included fertiliser production by recovering calcium phosphate fertilisers and ammonium sulphate fertilisers before and after the bio-brick production respectively. Producing 1000 bio-bricks a day would require 23% of Cape Towns’ population daily urine production and would incur a profit of ZAR 7330 per day between the raw material cost and the revenue from sales. For implementation in a South African context, certain policy barriers need to be overcome. Potential paths for implementation are reclassifying the urine for its use in an industrial process and obtaining an operating permit or seeking an exemption for a permit through the ECA (Environment Conservation Act). Research suggests that products from the integrated system are likely to be socially v accepted and that a combined appeal to people's environmental sensitivities and targeted marketing messages would enhance people’s acceptance. Finally, recommendations for further paths to take to build on the research established in this dissertation were made. It is recommended that additional characteristics of the bio-bricks should be tested, recycled material should be used as media for bio-bricks, the bacteria strain should be modified and methods for reducing the ionic strength of urine should be investigated. Additionally, it is recommended that consumers’ willingness to use urine-based products should be further studied, the legislative options for implementing bio-brick and fertiliser production should be investigated and a more detailed and expansive economic analysis should be performed.

Les bactéries marines biocalcifiantes induisent la précipitation du carbonate de calcium pouvant conduire à la formation de concrétions rocheuses. Des minéraux peuvent également précipiter et former des dépôts calcomagnésiens à la surface d’un métal placé sous polarisation cathodique dans l’eau de mer. Ce dépôt minéral, qu’il résulte d’un processus biologique ou électrochimique, peut faire office de ciment entre les sédiments conduisant à des structures résistantes qui pourraient être utilisées pour lutter contre l’érosion des côtes et protéger les ouvrages du littoral. L’objectif de ces travaux de thèse a donc été d’identifier des bactéries marines biocalcifiantes et d’évaluer leur potentiel biotechnologique dans la bioprécipitation de minéraux pour la formation d’agglomérats calcomagnésiens associés ou non à la polarisation cathodique. Nous avons montré pour la première fois que le dépôt calcomagnésien, formé électrochimiquement en milieu naturel, peut être colonisé par une grande diversité de microorganismes incluant des bactéries capables d’induire la précipitation du CaCO3. Nous avons pu isoler 14 souches bactériennes biocalcifiantes appartenant aux genres Pseudoalteromonas, Virgibacillus, Pseudidiomarina, Epibacterium, Planococcus et Bhargavaea. Aucune bactérie de ces 4 derniers genres n’avait auparavant été décrite comme biocalcifiante. A l’aide d’un nouveau dispositif expérimental, 10 des 14 bactéries biocalcifiantes ont formé des agglomérats sablo-calcaires en un mois grâce à leur métabolisme (uréase, anhydrase carbonique ou autres). La mise au point d’un autre montage expérimental associant polarisation cathodique et bactéries a permis de montrer qu’une densité de courant de -670 μA.cm-2 n’influence ni leur croissance ni leur production de CaCO3. Ces bactéries présentent donc un fort potentiel pour être utilisées en association avec la polarisation cathodique pour renforcer les digues et retarder l'érosion côtière
Biocalcifying marine bacteria induce the precipitation of calcium carbonate which can lead to the formation of rock concretions. Minerals can also precipitate and form calcareous deposits on the surface of a metal placed under cathodic polarisation in seawater. This mineral deposit, whether it results from a biological or electrochemical process, can act as a cement between the sediments leading to resistant structures that could be used to fight against coastal erosion and protect coastal structures. The objective of this work was therefore to identify biocalcifying marine bacteria and to evaluate their biotechnological potential in the bioprecipitation of minerals for the formation of calcareous agglomerates associated or not with cathodic polarisation. We showed for the first time that the calcareous deposit, formed electrochemically in a natural environment, can be colonised by a wide variety of microorganisms, including bacteria able to induce CaCO3 precipitation. We were able to isolate 14 biocalcifying bacterial strains belonging to the genera Pseudoalteromonas, Virgibacillus, Pseudidiomarina, Epibacterium, Planococcus and Bhargavaea. None bacterium of these latter 4 genera had previously been described as biocalcifying. Using a new experimental device, 10 of the 14 biocalcifying bacteria formed sand-calcareous agglomerates in one month thanks to their metabolism (urease, carbonic anhydrase or others). The development of another experimental setup associating cathodic polarisation and bacteria made it possible to show that a current density of -670 μA.cm-2 influenced neither their growth nor their production of CaCO3. These bacteria therefore have great potential to be used in combination with cathodic polarisation to strengthen dikes and delay coastal erosion

The purpose of the creation of Go Natural’s supermarket online store and subsequent marketing plan is to introduce and launch a new option for consumers who want to have healthy, bio and allergy-friendly foods at the distance of one click. The website will offer a wide selection of goods with fair prices, as it happens already in the physical stores across Lisbon and Porto. To better understand how this new service could offer a solution to the modern society and how it could bring some benefits to the brand itself and Sonae as the owner, extensive analysis were developed in order to identify and understand how the most diverse factors could, eventually, affect our website. Likewise, in this project we acknowledged the potential market and made a strategic study that will allow us to better evaluate what resources will be needed for the implementation of this new service. Accordingly, a marketing plan was delineated and the respective marketing mix components were considered in order to build a website that answers successfully to modern consumers’ demand.
O objectivo para a criação da loja online para o supermercado Go Natural e subsquente plano de marketing é introduzir e lançar uma nova opção no mercado para os consumidores que querem ter acesso a comida saudável, biológica e específica para alergias alimentares à distância de apenas um click. A página oferecerá uma vasta selecção deste tipo de produtos com preços acessíveis, tal como já acontece nas lojas físicas da marca espalhadas por Lisboa e Porto. Para melhor percepcionar e entender de que maneira este novo serviço pode oferecer uma solução para a sociedade actual e como pode beneficiar não só a insígnia em si mas também a Sonae como empresa detentora, várias análises extensivas foram desenvolvidas de forma a identificar e compreender de que maneira diversos factores poderiam, eventualmente, afectar o lançamento do website. Assim, neste projecto reconhecemos o mercado potencial e desenvolvemos um estudo estratégico de modo a avaliar que recursos serão necessários para a implementação deste novo serviço. Desta forma, um plano de marketing foi delineado e os respectivos componentes do marketing mix foram considerados de maneira a construir um site que responda eficientemente à crescente procura dos consumidores.

Crude bricks are composite materials manufactured with sediments and natural fibers. Natural fibers are waste materials and used in construction materials for reinforcement. Their reuse in manufacturing reinforced crude bricks is eco-friendly and improves mechanical and thermal characteristics of crude bricks. Factors such as type of fibers, percentage of fibers, length of fibers and distribution of fibers inside the bricks have significant effect on mechanical, physical and thermal properties of biobased composite materials. It can be observed by tests such as indirect tensile strength, compressive strength for mechanical characteristics, density, shrinkage, color for physical properties, thermal conductivity and resistivity for thermal properties, and inundation test for durability of crude bricks. In this study, mechanical and physical characteristics of crude bricks reinforced with palm oil fibers are investigated and effect of change in percentage and length of fibers is observed. Crude bricks of size 4*4*16 cm3 are manufactured with dredged sediments from Usumacinta River, Mexico and reinforced with palm oil fibers at laboratory scale. For this purpose, sediments and palm oil fibers characteristics were studied. Length of fibers used is 2cm and 3cm. Bricks manufacturing steps such as sediments fibers mixing, moulding, compaction and drying are elaborated. Dynamic compaction is opted for compaction of crude bricks due to energy control. Indirect tensile strength and compressive strength tests are conducted to identify the mechanical characteristics of crude bricks. Physical properties of bricks are studied through density and shrinkage. Durability of crude bricks is observed with inundation test. Thermal properties are studied with thermal conductivity and resistivity test. Distribution and orientation of fibers and fibers counting are done to observe the homogeneity of fibers inside the crude bricks. Finally, comparison between the mechanical characteristics of crude bricks manufactured with 2cm and 3cm length with control specimen was made.

This study focus on the effects of both water content and cement stabilization on the fire behavior of earth bricks. To observe the effect of cement stabilization, two materials are formulated: raw earth with only soil and water, and stabilized bricks with soil, water and cement (3.5% by mass of soil). Since the material’s mechanical strength can strongly influence its fire behavior, the raw bricks were compacted at 50 MPa to reach a compressive strength similar to the one of stabilized bricks. Four different water contents were tested; dry state obtained with oven drying and three others achieved through equalization at 50%, 75% and 100% of relative humidities. Bricks are then subjected to an ISO 834-1 standard fire. Results show that water content has caused a thermal instability behavior on the raw earth bricks after equalization at 50% and 75% relative humidities. Thermally stable bricks displayed a noticeable diffusion of cracks on their heated face. Furthermore, cement stabilization helps to prevent from thermal instabilities.

Weak water resistance is a big obstacle for clay materials to overcome in modern construction industry. Compared to the hydraulic stabilized additives, bio-additives have a lower carbon footprint and have been used in many vernacular construction techniques to immobilize clay. In this work, the traditional recipes of tannin and iron have been revisited, in particular, the question of pH and iron solubility has been explored. Oak tannin and FeCl3 were chosen and their influence on the properties of clay materials in terms of rheological properties, compressive strength, and water resistance were characterized in the lab. Based on the results, tannin can reduce the yield stress of paste while with the addition of FeCl3, the yield stress of tannin dispersed pastes increased to a value similar to the reference sample but lower than the value contain only FeCl3. The increase was attributed to the complex reaction between tannin and Fe3+. The iron-tannin complexes can also increase the samples’ strength and water resistance. Although the complexes did not change the hydrophilic properties of the samples’ surface, they prevent the ingression of water. These results are very promising as they allow the production of a fluid earth material that is water-resistant. This opens a wide range of application potentials and can help to mainstream earth materials in construction.

Clay is one of the earliest known material used in construction, and the most widely used building material on the planet. Our ancestors have performed the tasks of mixing water with dust to make clay, then shaping it into bricks, bricks into buildings, and buildings into cities for more than ten thousand years. In recent years, 3D printing technology has become increasingly popular thanks to its ability to manufacture complex morphologies and to optimize physical and mechanical properties for specific applications. This study investigates customized 3D clay bricks as a new building material (building component) by employing resources that are eco-friendly, locally available, inexpensive, and driven from recycled sources or waste streams. In this experiment, four different fiber types have been investigated with different clay treatment. The specimens were fabricated in the laboratory and tested with unconfined compression loading. The strength and ductility of the clay specimens were then analyzed based on the experiment results. Several experiments have been conducted during the study for understanding the effects of different fibers when mixed with clay in order to identify which type of fibers and which size has the most effective influence on its compression strength. Furthermore, it has been tested also the water absorption of the 3D printed brick. A case study has been developed to show the actual potential of 3D printed clay bricks for a small housing complex. The project is located in a village near to Abuja, Nigeria, at a time of exponential population increase and associated lack of affordable housing. The 3D printed blocks embed a cooling function, thanks to their geometry and the presence of cooling pipes directly in the wall. The result is a highly flexible envelope, designed to be resilient and energy efficient.