Feasibility study on the fabrication of eco-friendly construction material from dye industry wastewater treatment sludge

• Main Author: Toh, Wei Hong
• Format: Final Year Project / Dissertation / Thesis
• Published: 2024
• Subjects: TD Environmental technology. Sanitary engineering; TP Chemical technology
• Online Access: http://eprints.utar.edu.my/6600/1/Toh_Wei_Hong_1903572.pdf; http://eprints.utar.edu.my/6600/

The construction industry is rapidly developing in the whole world due to urbanization and population growth. The rising demand for housing infrastructure caused increased construction activity, leading to a high volume of brick manufacture. Fired brick is the most common brick that is used in construction due to low maintenance and high durability. However, the production of fired brick releases many toxic gases and carbon footprints that can cause serious air pollution. Therefore, cement sand brick (CSB) also known as non-fired brick is invented to substitute fired brick as it is more environmentally friendly and easier to manufacture. Although it can decrease the demand for fired brick, development in CSB also leads to a massive amount of cement production. The cement manufacturing sector is a major contributor to greenhouse gas emissions that will lead to climate change and dust pollution. On the other hand, textile dyeing sludge is a hazardous industrial waste produced via textile dyeing wastewater treatment system. It contains various toxic organic compounds that can affect the aquatic environment if it is not managed properly. Thus, textile dyeing sludge (TDS) is chosen for the substitution of cement in the fabrication of CSB in order to minimize the production of cement while also lowering TDS generation. The objectives of this research are to study the feasibility of the fabrication of eco-friendly cement sand bricks with partial replacement of sludge from dye industry wastewater treatment. Besides that, this research aims to analyse the engineering properties and durability characteristics of the CSB to identify the optimum TDS replacement percentage TDS. The substitution percentage of TDS is 5%, 10%, and 15%, at the same time two different particle size ranges of TDS will be tested in this feasibility study. All the specimens in this study were tested in three different curing periods (7, 14, and 28 days), and analysed the engineering properties and durability of the specimens after being replaced with textile dyeing sludge. The tests included compressive strength, microstructure analysis, flexural strength, water absorption, bulk density, and porosity. After the tests, this feasibility study found that the substitution of textile dyeing sludge does not increase the engineering properties and durability characteristics of CSB due to the lower amount of calcium oxide (CaO) content, higher sulphate concentration, and excessive Loss of Ignition (LOI) value that can produce pores and voids to affect its durability. However, the optimum specimen is 15FTDS as it satisfies all the standard requirements. The final test result of the 15FTDS is compressive strength: 8.07 MPa; flexural strength: 1.52%; bulk density: 1784.51kg/m3 ; porosity: 23.14%; water absorption: 9.09%. In addition, the substitution of 15 % TDS reduces the total carbon dioxide (CO2) emissions by 14.64% per unit and 11.86% of production cost compared to conventional CSB which promotes a more sustainable future. In conclusion, the replacement of cement with TDS in the fabrication of CSB is feasible to achieve sustainable new product generation by reducing waste production and resource consumption which is addressed by Sustainable Development Goals (SDGs) (SDG 1, SDG 9, SDG 11, SDG 12, and SDG 13.) and promoting circular economy by utilizing waste material from the dye manufacturing industry