Search results

In the current scenario, air pollution and soil pollution from the industries wastes are one of the major problems all over the world. Further, disposal of these wastes from industries are very costly. However, several attempts were carried out by various researchers in the past to use these wastes. One of the most common waste products is bagasse from sugar industries. These hazardous bagasse wastes lead to air and soil pollution. This study aims to recycle bagasse waste in the development of aluminium base composite as partial replacement of ceramic particles.

In the present investigation, recycled bagasse waste was used in the development of aluminium base composite as partial replacement of ceramic particles such as SiC, Al₂O₃ and B₄C. Production industries of these ceramic particles (SiC, B₄C and Al₂O₃) emit huge amount of greenhouse gases such as N₂O₃, CH₄, CO₂ and H₂O. These green house gases produce lots of environment problem. Furthermore, production of these ceramic particles is also costly. AA6061 aluminium alloy was taken as matrix material. Composite material was developed using the stir casting technique.

Microstructure results showed proper distribution of bagasse ash and MgO powder in the aluminium base metal matrix composite. It was notified from analysis that minimum corrosion loss and minimum porosity were found for Al/2.5% bagasse ash/12.5% MgO powder composite. For the same composition, hardness and thermal expansion were also observed better as compared to other selected compositions. However, density and cost of composites continuously decrease by increasing percentage of bagasse ash in development of composite.

Results showed about 11.30% improvement in tensile strength, 11.64% improvement in specific strength and 40% improvement in hardness by using bagasse ash as reinforcement with MgO powder in development of aluminium base composite.

The change in climate and depletion of natural resources because of the harmful emissions from different materials becomes a main issue for the globe. Some of the developed and developing countries have focused on this issue and performed research to provide a solution. The purpose of this study is to identify the best types of concrete based on its impact on the environment and economy.

The life cycle assessment and life cycle cost analysis of six concrete mixtures that include construction and demolition wastes (CDW), marble sludge, rice husk and bagasse ash as a partial replacement of cement, are performed. These types of concrete are compared with each other and with ordinary concrete to select the best possible concrete type for a developing country, like Pakistan.

The results show that, although for an agricultural country like Pakistan, the agriculture wastes such as rice husk and bagasse ash are preferable to be used, if the emissions of CO₂ and CO from rice husk and NOx and SO₂ from bagasse ash are properly controlled. However, based on the results, it is recommended to use the CDW in concrete because of the small amount of air emissions and affordable prices.

Through this study, a path has been provided to construction companies and relative government organizations of Pakistan, which leads to sustainable practices in the construction industry. Moreover, the base is provided for future researchers who want to work in this area, as for Pakistan, there is no database available that helps to identify the impact of different concrete on the environment.

Utilising industrial waste, such as fly ash (FA) and bagasse ash (BA), reduces waste management and increases mechanical strength. Concrete is modified with FA and BA in the cool bonded method of concrete preparation.

The study used to partially replace cement with BA powder at proportions 0, 5, 10, 15, 20 and 25% and coarse aggregates are replaced with FA aggregates made with FA and cement using a cold-bonded technique at proportions 0–25%. FA aggregates were made at 10:90, 15:85, 20:80 and 25:75 proportions of cement and FA. The FA aggregates at the best proportion 15:85 was selected as a coarse aggregate by conducting tests like specific gravity, crushing value, impact value and water absorption tests.

The addition of 30% content decreases porosity by 21% and increases strength significantly at 28 days. Microstructure evolution is carried out to identify material behaviour.

Mechanical and durable properties such as flexural strength, tensile strength, water absorption test, acid and alkaline tests are conducted on M50 grade concrete after 3–28 days of curing.

The conflicting results on the corrosion characteristics of aluminium matrix composites reinforced with agrarian waste have stimulated an investigation on the hardness and corrosion rate of sugar palm fibre ash (SPFA) reinforced LM26 Al/alloy composite by varying the SPFA from 0 to 10 wt% in an interval of 2 wt%. This paper aims to discuss the aforementioned issue.

The composites were produced via stir-casting and the hardness was determined using a Vickers hardness testing machine, corrosion rate was examined through the weight loss method by immersion in 0.5, 1.0 and 1.5 M hydrochloric acid (HCl) at temperatures of 303, 318, and 333 K for the maximum duration of 120 h. The morphological study was conducted using a scanning electron microscope (SEM) on the samples before and after immersion in HCl.

The incorporation of SPFA improved the hardness of the alloy from 58.22 to 93.62 VH after 10 wt% addition. The corrosion rate increases with increased content of SPFA, the concentration of HCl and temperature. The least corrosion rate of 0.0272 mpy was observed for the LM26 Al alloy in 0.5 M after 24 h while the highest corrosion rate of 0.8511 mpy was recorded for LM26 Al/10 wt% SPFA in 1.5 M HCl acid after 120 h. The SEM image of corroded samples revealed an increased number of pits with increased SPFA content.

The work is limited to SPFA up to 10 wt% as reinforcement in LM26 Al alloy, the use of HCl as corrosion medium, temperatures in the range of 303–333 K, and a weight loss method were used to evaluate the corrosion rate.

The corrosion rate was determined for LM26 Al/SPFA composites with various amounts of SPFA in 0.5, 1.0 and 1.5 M HCl at 303, 318 and 333 K and compared with the matrix alloy.

This study aims to investigate the properties of mortar made from a bottom ash substitute as a sustainable construction material. It is believed that the use of cement in concrete construction contributes to the release of carbon dioxide into the atmosphere, which has been a consistent increase in recent years. The utilization of bottom ash waste is expected to reduce pollution associated with cement production.

Bottom ash is used as replacement materials for cement and fine aggregate in the manufacture of mortar. Bottom ash substituted for cement of 10%, 20% and 30% of the total weight of the binder, whereas bottom ash substituted for the fine aggregate of 30%, 40% and 50% of the total weight of the sand. Binder properties were determined using scanning electron microscopy and energy dispersive X-ray. Meanwhile, the fresh properties (slump flow) and hardened properties were determined (compressive strength and mass density). In the hardened properties test, two types of curing were used: water and sealed curing.

The compressive strength of mortar decreased as the amount of bottom ash as cement replacement. However, the compressive strength increased when bottom ash was used as aggregate replacement. Additionally, bottom ash was sufficient as a substitute for fine aggregate than as a substitute for cement.

This research presents test results that are more straightforward to apply in the construction site.

Bioconcrete is widely believed to be environmentally beneficial over conventional concrete. However, the process of bioconcrete production involves several steps, such as waste recovery and treatment, that potentially present significant environmental impacts. Existing life-cycle assessments of bioconcrete are limited in the inventory and impact analysis; therefore, they do not consider all the steps involved in concrete production and the corresponding impacts. The purpose of this study is to extensively study the cradle-to-gate environmental impacts of all the production stages of two most common bioconcrete types (i.e. sludge-based bioconcrete and cement kiln dust-rice husk ash (CKD-RHA) bioconcrete) as opposed to conventional concrete.

A cradle-to-gate life-cycle assessment process model is implemented to systematically analyze and quantify the resources consumed and the environmental impacts caused by the production of bioconcrete as opposed to the production of conventional concrete. The impacts analyzed in this assessment include global warming potential, ozone depletion potential, eutrophication, acidification, ecotoxicity, smog, fossil fuel use, human toxicity, particulate air and water consumption.

The results indicated that sludge-based bioconcrete had higher levels of global warming potential, eutrophication, acidification, ecotoxicity, fossil fuel use, human toxicity and particulate air than both conventional concrete and CKD-RHA bioconcrete.

The contribution of this study to the state of knowledge is that it sheds light on the hidden impacts of bioconcrete. The contribution to the state of practice is that the results of this study inform the bioconcrete production designers about the production processes with the highest impact.

The purpose of this paper is to study Al-based green composite. To make composite samples of aluminium alloy (AA3105) with different weight percentages of rice husk ash (RHA) and eggshell (ES) particles as reinforcement, stir casting method was used.

Several other aspects, including the weight percent of reinforcing agent particles, the applied stress and the sliding speed, were taken into consideration. During the course of the wear test, the sliding distance that was recorded varied from a minimum of 1,000 m all the way up to a maximum of 3,135 m (10, 15, 20, 25 and 30 min). The typical range for normal loads is 8–24 N, and their speed is 1.58 m/s.

With the AA/ES/RHA composite, the wear rates decreases when the grain size of the reinforcing particles enhanced. Scanning electron microscopy images of worn surfaces show that at low speeds, delaminating and ploughing are the main causes of wear. At high speeds, ploughing is major cause of wear. Composites with better wear-resistant properties can be used in wide range of tribological applications, especially in the automotive industry. It was found that hardness increases at the same time as the weight of the reinforcement increases. Tensile and hardness were maximized at 10% reinforcement mix in Al3105.

In this work, ES and RHA has been used to develop green metal matrix composite to support green revolution as promoted/suggested by United Nations thus reducing the environmental pollution.

Successful project delivery for sustainable building construction (SBC) has been linked to certain features. Previous studies have emphasised the need to improve SBC practice in South Africa. The purpose of this study is to explore the SBC features for project delivery in South Africa.

A structured questionnaire elicited the primary data from 281 built environment professionals, mainly in South Africa’s Gauteng province. Descriptive and inferential statistics were used for the data analysis. This study used the principal component analysis technique to ascertain the principal SBC features.

Three components of SBC features, namely, sustainable resource use and compliance, sustainable waste minimisation and recycling and sustainable designs and materials, were developed from the principal component analysis. The factor loadings of the constituent variables ranged from 0.570 to 0.836. The reliability of each component was evaluated, and the results were 0.966, 0.931 and 0.913.

The revelations from this study will aid the decision-making of the relevant stakeholders towards establishing improvement initiatives and mitigating the reluctance to shift from conventional building methods and poor knowledge sharing of SBC benefits.

This is one of the most recent South African studies that sheds light on the components of a successful SBC deployment. The findings of this study added to knowledge by confirming three fundamental features of SBC. This study recommends adequately considering the principal features for successful SBC project delivery in South Africa.

Utilization of industrial and agricultural waste products as cement replacement materials in concrete technology has been an interesting subject of research for economical, environmental, and technical reasons. Portland cement incorporating these cement replacement materials improves corrosion resistance of carbon steel. Sugar cane bagasse is considered as waste in sugar mills and dumped in open space or used as fuel for boilers. The main purpose of the study is to investigate corrosion performance of reinforcing carbon steel in bagasse ash (BA) blended cement concrete and compare it with control concrete.

BA is prepared by burning boiler‐fired ash at a controlled temperature of 650°C for 1 h and cooled. The ash is then ground to a fineness of 46 μm as Pozzolanic material and blended in concrete in various cement replacement levels. The corrosion behaviour of carbon steel in BA blended concretes exposed to alternate dry‐wet cycles in 3.0 percent NaCl solution for 18 months was studied using gravimetric weight loss, linear polarization, and electrochemical impedance measurement techniques. The resistance to chloride ion penetration of BA blended concretes after 28 and 90 days and compressive strength of BA blended concrete cubes after 7, 14, 28, and 90 days curing also was evaluated.

The experimental results indicated that the corrosion rate of reinforcing steel and chloride penetration were significantly reduced, and compressive strength was increased, with the incorporation of BA up to 20 percent replacement in concrete. It was observed also that a relatively good correlation between linear polarization and impedance measurements with respect to corrosion current values on the reinforcing steel within BA blended concretes.

BA may be considered as a better substitute than other mineral admixtures for durable concrete structures. The study fulfilled the objective of the investigation and contributes to research on corrosion protection of carbon steel in concrete.

Lignin precipitated from different black liquors wasted from the cooking of rice straw, bagasse and cotton stalks, to produce pulp and paper, can replace phenol by up to 40 per cent in phenol formaldehyde resin. The properties of the resin produced from bagasse lignin formaldehyde are nearly the same as when the resin IS produced from phenol formaldehyde. Replacement of phenol by lignin in phenol formaldehyde resin has an economical effect and reduces the pollution caused by draining black liquor into rivers and streams. The properties of the resin produced from rice straw lignin are lower than resin from bagasse and cotton stalk lignin. The effect of increasing the content of lignin in the resin on the resin properties was studied. The effect of polymerization time and temperature on the resin properties is also clarified. The molecular structure of the lignins used plays an important role on the properties of the phenol lignin formaldehyde produced.