The purpose of this study was to investigate the best ratio of waste foundry sand (WFS), fly ash (FA), and electric arc furnace slag (EAF slag) for the production of geopolymer bricks. In this research study, WFS, FA, and EAF slag were mixed at the ratio of 70:30:0, 60:30:10, 50:30:20, and 40:30:30 with 8M sodium hydroxide (NaOH) and 98% purity sodium silicate (Na2SiO3) with a ratio of Na2SiO3/8M NaOH = 2.5. The mixtures were compacted in 5 cm × 5 cm x 5 cm molds and cured at an ambient temperature for 28 days. Then, their compressive strength was analyzed. The results showed that the geopolymer bricks with the highest compressive strength were those mixed at the 40:30:30 ratio, with a compressive strength of 25.76 MPa.
The strongest bricks were also analyzed using the leaching test to ensure the production involved non-hazardous materials. To compare the environmental impacts of geopolymer bricks and concrete bricks, their effects on climate change, ozone depletion, terrestrial acidification, human toxicity, terrestrial ecotoxicity, and fossil fuel depletion were examined from cradle to grave using SimaPro 188.8.131.52 software. The results of the life cycle assessment (LCA) from cradle to grave showed that the environmental impact of geopolymer brick production was lower in every aspect than that of concrete production. Therefore, geopolymer brick production can reduce environmental impact and can be a value-added use for industrial waste.
For further information, please download
Maize is an important material for feed production in Thailand. In the past 10 years, the demand of feed production has increased significantly, resulting in the increasing demand of maize. In this research, Material Flow Analysis was applied to track flows of raw materials and resources used in maize supply chain in Thailand in 2015.
Thailand produces one-third of the world’s total natural rubber and is the top supplier of natural rubber to Europe. The European Product Environmental Footprint (PEF) plays an essential role in reducing the environmental impacts of the rubber products imported into Europe. This is the first work to evaluate the PEF of fresh latex, cup lump, and hevea wood from the plantation phase (primary products) and the PEF of intermediate rubber products: ribbed smoked sheets (RSS), ribbed smoked sheet bales (RSSB), block rubber (Standard Thai Rubber, STR 20), concentrated latex, and lumber AB in Thailand.
Data quality of life cycle inventory background databases should be ensured in order to be useful for life cycle assessment (LCA) studies. However, databases do not always have procedures to evaluate the quality of the data sets in place. The Global Guidance Principles for LCA Databases of the United Nations Environment Programme (UNEP) in collaboration with the Society of Environmental Toxicology and Chemistry (SETAC) provide, among others, recommendations to enhance data quality through improved documentation and review.