Aeslina Abdul Kadir

BRICKS: AN EXCELLENT BUILDING MATERIAL FOR RECYCLING WASTES - A REVIEW

Brick is one of the most common masonry units as a building material due to its properties. Many attempts have been made to incorporate wastes into the production of bricks, for examples, rubber, limestone dust, wood sawdust, processed waste tea, fly ash, polystyrene and sludge. Recycling such wastes by incorporating them into building materials is a practical solution for pollution problem. This paper reviews the recycling of different wastes into fired clay bricks. A wide range of successfully recycled materials and their effects on the physical and mechanical properties of bricks have been discussed. Most manufactured bricks with different types of waste have shown positive effects on the properties of fired clay bricks.

A practical proposal for solving the world’s cigarette butt problem: Recycling in fired clay bricks

The disposal and littering of cigarette butts (CBs) is a serious environmental problem. Trillions of cigarettes are produced every year worldwide, resulting in millions of tonnes of toxic waste being dumped into the environment in the form of cigarette butts. As CBs have poor biodegradability, it can take many years for them to break down. This paper reviews and presents some of the results of a study on the recycling of CBs into fired clay bricks. Bricks with 2.5%, 5%, 7.5%, and 10% CB content by weight were manufactured and tested, and then compared against control clay bricks with 0% CB content. The results showed that the dry density decreased by up to 30% and the compressive strength decreased by 88% in bricks with 10% CBs. The calculated compressive strength of bricks with 1% CBs was determined to be 19.53Mpa. To investigate the effect of mixing time, bricks with 7.5% CB content were manufactured with different mixing times of 5, 10, and 15min. To test the effect of heating time on the properties of CB bricks, the heating rate used during manufacturing was changed to 0.7, 2, 5, and 10°Cmin(-1). Bricks with 0% and 5% CB content were fired with these heating rates. Leachate tests were carried out for bricks with 0%, 2.5%, 5%, and 10% CB content. The emissions released during firing were tested for bricks with 0% and 5% CB content using heating rates of 0.7, 2, 5, and 10°Cmin(-1). The gases tested were carbon monoxide (CO), carbon dioxide (CO2), chlorine (Cl2), nitrogen oxide (NO), and hydrogen cyanide (HCN). Finally, estimations were made for the energy that could be saved by firing bricks incorporating CBs. Calculations showed that up to 58% of the firing energy could potentially be saved. Bricks were shown to be a viable solution for the disposal of CBs. They can reduce contamination caused by cigarette butts and provide a masonry construction material that can be either loadbearing or non-loadbearing, depending on the quantity of CBs incorporated. This paper proposes the use of bricks with 1% CB content throughout the brick-manufacturing industry. If bricks contained as little as 1% CB content, they would still provide a solution for the issue of CB recycling while maintaining properties very similar to those of a non-CB brick. Our calculations show that, theoretically, only 2.5% of the worlds annual brick production is necessary to completely offset the worldwide, annual cigarette production.

Relationship Between Compressive, Splitting Tensile and Flexural Strength Of Concrete Containing Granulated Waste Polyethylene Terephthalate (PET) Bottles as Fine Aggregate

This paper describes the experimental investigation of relationship between splitting tensile strength and flexural strength with the compressive strength of concrete containing waste PET as fine aggregates replacement. Waste PET was reprocesses and used as the artificial fine aggregate at the replacement volume of 25%, 50% and 75%, Cylindrical and prism specimens were tested to obtain the compressive, splitting tensile and flexural strength at the age of 28 days. Based on the investigation, a relationship for the prediction of splitting tensile and flexural strength was derived from the compressive strength of concrete containing waste PET as fine agglegate replacement.

Testing on Building Material Using Waste Material in Fired Clay Brick

Clay brick is one of the building materials that have been used in the construction field for thousand years. It has been used as a major construction material because it can tolerate with severe weathering action, flexible properties and it is easy to handle. Many researchers have been incorporated waste material such as organic waste, waste treatment sludge, fly ash, cigarette butts, rice husk and processed waste tea into fired clay brick. This application gives an idea to use waste material that will give a minimum impact to the real environment. In this study, high calorific value waste such as cigarette butts (CBs) were incorporated into fired clay brick. Different percentages of CBs (0%, 2.5% and 5.0%) were added into the raw clay brick. All samples were fired up to 1050°C with different heating rates (1°C/min, 3°C/min and 5°C/min). Properties including compressive strength, dry density, firing shrinkage and water absorption are reported and discussed. The results show that the compressive strength of fired clay brick was obtained with 2.5% CBs of fired clay brick at 1°C/min heating rate compared to others. As for the density, it was reduced with higher percentages of CBs incorporated into the raw clays. From the results, water absorption was slightly increased when CBs were incorporated into clay brick. The results suggested that heating rates at 1oC/min is adequate to achieve optimum properties.

Smart Recycle Bin: A Conceptual Approach of Smart Waste Management with Integrated Web Based System

Nowadays, the trend is clear that the use of pervasive computing technology has taken place to improve waste management by providing electronic system which utilizing radio frequency identification at bin level. In this paper, we proposed a smart recycle bin application based on information in the smart card to automatically calculate the weight of waste and convert the weight into point then store it into the card. The wastes are tracked by smart bins using a RFID-based system integrating the web-based information system at the host server. Two crucial features of the selective sorting process can be improved using this approach. First, the user is assisted in the application of material waste classification. Second, the smart bin knows its content and can report back to the rest of the recycling chain.

Leachability of Fired Clay Brick Incorporating with Sludge Waste from Mosaic Industry

The amount of sludge wastes from industrial, mining, domestic agriculture activities are about 60200 tons per year. The increasing of the waste will have significant impact towards environment and energy conservation. Many attempts have been made to incorporate sludge waste into brick for example fly ash sludge, sewage sludge, water sludge and ceramic sludge and advantages on the properties have been found but heavy metals leachibility will be the main concerned. Therefore, sludge waste is a potential alternative to convert into useful products as a building material that can alleviate the disposal problems. Therefore, in this study, the characteristics of heavy metals were determined by using XRF. Four different mixing ratios of mosaic sludge waste at (0%, 1%, 5%, and 10%) were incorporated into fired clay brick. Each brick was fired in a heat controlled furnace at elevated temperatures of 1050°C. The characteristic of heavy metals from the sludge waste were determined by XRF and the result show that the sludge waste is high in iron (Fe) and Zicronium (Zr) followed by Barium (Br), Chromium (Cr), Cadmium (Cd), Copper (Cu) and Zinc (Zn). The leachability of heavy metals from the manufactured mosaic sludge brick were determined by using toxicity characteristic leachibility procedure (TCLP) and the results demonstrated that the culprit heavy metals were all complied to USEPA(1996) and EPAV(2005a).

Physical and Mechanical Properties of Fired Clay Bricks Incorporated with Cigarette Butts: Comparison between Slow and Fast Heating Rates

In general, firing process in brick manufacturing could affect the properties, colours and appearance of the brick. The main purpose of this study was to evaluate the effect of different heating rates on physical and mechanical properties during the firing of standard bricks and bricks incorporated with cigarette butt (CB). In this investigation, two different heating rates were used: slow heating rate (2oC min-1) and fast heating rate (5oC min-1). Samples were fired in solid forms from room temperature to 1050oC. All bricks were tested for their physical and mechanical properties including compressive strength, initial rate of absorption and density. Higher heating rates decrease compressive strength value but slightly increase the initial rate of absorption and density properties respectively. In conclusion, higher heating rates are able to produce adequate physical and mechanical properties especially for CB Brick.

Development of Concrete Mix Design Nomograph Containing Polyethylene Terephtalate (PET) as Fine Aggregate

This paper describes the experimental investigation to develop the concrete mix design Nomograph for concrete containing PET as fine aggregate. The physical and mechanical properties were determined by using mix proportion containing 25%, 50% and 75% of PET with water cement ratio (w/c) 0.45, 0.55 and 0.65. The data obtained showed that the inclusion of PET aggregate reduce the strength performances of concrete. All the data obtained were combined into one single graph to develop a preliminary mix design nomograph for PET concrete. The nomograph consist of ; relationship between compressive strength and water cement ratio; relationship between splitting tensile strength water cement ratio; relationship between splitting tensile strength and PET percentage and relationship between compressive strength and PET percentage. The mix design nomograph can be used to assists in selecting the proper mix proportion parameters based on the criteria required.

Properties improvement of fired clay bricks incorporating with cigarette butts

Although small in size, indiscriminate littering of cigarette butts (CBs) can cause serious environmental impact. Several trillion cigarettes produced worldwide annually lead to thousands of kilograms of toxic waste. CBs accumulate in the environment due to the poor biodegradability of the cellulose acetate filters and, in doing so, they have become the most common litter item on our planet. This paper presents some of the results from a continuing study on recycling CBs into fired clay bricks. Physico-mechanical properties of fired clay bricks manufactured with different percentages of CBs (2.5%, 5% and 10%) and also of control brick samples are reported and discussed. To improve the properties, three different mixing times were tested with 7.5% of CBs incorporated in clay bricks, specifically at 15 minutes, 10 minutes and 5 minutes respectively. The impacts of these changes on physical and mechanical characteristics were evaluated. With 15 minutes mixing time, the measurement increased up to 114% and 12% for strength and density respectively compared to 5 minutes mixing time. On the other hand, values for water absorption, initial rate of absorption and tensile strength decreased by 22%, 29% and 5% respectively. Microstructure analyses of CB bricks were also investigated using ESEM. Attempts were also made to improve the properties by incorporating 3% of steel fibre into CB brick samples. Nevertheless, the addition of the steel fibre did not significantly improve the properties or the appearance of the manufactured samples.

Investigation on leaching behaviour of fly ash and bottom ash replacement in self-compacting concrete

Fly ash and bottom ash are some of the waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. In recent years, many researchers have been interested in studying on the properties of self-compacting concrete incorporated with fly ash and bottom ash but there was very limited research from the combination of fly ash and bottom ash towards the environmental needs. Therefore, this research was focused on investigating the leachability of heavy metals of SCC incorporated with fly ash and bottom ash by using Toxicity Characteristic Leaching Procedure, Synthetic Precipitation Leaching Procedure and Static Leaching Test. The samples obtained from the coal-fired power plant located at Peninsula, Malaysia. In this study, the potential heavy metals leached out from SCC that is produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a substitute for sand with the ratios from 10% to 30% respectively were designated and cast. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results indicated that most of the heavy metals leached below the permissible limits from the United States Environmental Protection Agency and World Health Organization limit for drinking water. As a conclusion, the minimum leaching of the heavy metals from the incorporation of fly ash and bottom ash in self-compacting concrete was found in 20% of fly ash and 20% of bottom ash replacement. The results also indicate that this incorporation could minimize the potential of environmental problems.