Displaying items by tag: sludge

Germany: The University of Trier is transforming post-consumer materials into ‘ecological’ cement through a new research project that aims to find sustainable alternatives for the construction industry. The project involves using low-CO₂ industrial post-consumer materials as alternative cement binders, such as sludge from gravel and sand mining, as well as dust from quartzite extraction. The research will run for two years and is supported by the German Federal Environment Foundation.

South Korea: South Korean cement manufacturers recently convened at an event hosted by the Korea Cement Association and the Korea Industry Alliance Forum to discuss how to achieve carbon neutrality. The industry currently faces financial challenges in upgrading equipment due to low cement prices. However, it has achieved a 20% decrease in greenhouse gas emissions per tonne of cement since 2014, aided by the use of alternative fuels and investment in energy efficiency. The Korean government now requires that greenhouse gases be cut by 12% by 2023 from 2018 levels by 53% by 2050.

The industry currently uses post-consumer plastics as fuels instead of fossil fuels and incorporates byproducts from other industries, like sludge. However, some environmental groups have labelled cement made from industrial byproducts as ‘garbage cement’ claiming it contains hexavalent chromium levels more than four times the EU’s allowable limits. The use of plastics as alternative fuel has also sparked complaints from local waste collection and incineration companies, who argue that cement companies are taking away their business.

Professor Kim Jin-man from Kongju National University said "We also need to focus on developing high-performance clinker, advanced chemical admixtures for concrete, and accelerators that shorten concrete curing times."

Azerbaijan: Norm Sement Company will utilise sludge from drilling wells for powering its cement plant, following an agreement with the State Oil Company of Azerbaijan (SOCAR), according to Trend. The plant has a capacity exceeding 2.1Mt/yr of cement and 5300t/day of clinker.

A source said "In collaboration with SOCAR, we tried sludge to power Norm Sement last year. Negotiations on a long-term deal are underway. Cooperation to use industrial waste supports the country's green economy strategy.”

Philippines: Cemex Philippines has secured a contract with Manila Water Company for the supply of biosolids from sewage processing for use as alternative fuel (AF). Cemex Philippines has already taken receipt of 10t of biosolids at its Antipolo cement plant in Luzon's Calabarzon Region.

Cemex Philippines’ sustainability and public affairs director Christer Gaudiano said “As pioneers of the use of biosolids as AF in the country, we have just signed what will now create the series of significant steps towards making circular economy a reality."

Sustainability initiatives form one arm of Asian Development Bank (ADB) and the ASEAN Capital Markets Forum's Golden Arrow award for good management, which Cemex Philippines won for the second time on 9 February 2023.

South Korea: SK Ecoplant is at the centre of an initiative in partnership with the city administration of Seoul to co-process 52,000t/yr of incineration ash and 110,000t/yr of sewage sludge from the city in local cement production. AJU News has reported that the waste management company expects to supply the raw materials to make 150,000t/yr of cement production under the initiative.

Seoul generates 113,000t/yr of incineration ash and 200,000t/yr of sewage sludge. Currently, recycled incineration ash is used in concrete block and paving slab production, which have a limited strength when using the material.

Signapore: Researchers at the Nanyang Technological University in Singapore (NTU Singapore) have successfully used bacteria to combine two abundant waste streams into clinker-free biocement. NDTV news has reported that the scientists developed the material from by combining calcium ions with urea in a mixture of industrial carbide sludge and urine. The process takes place at room temperature, reducing CO₂ emissions while also offering waste management benefits.

The NTU Singapore team is presently testing the biocement on artificial beaches. It will subsequently investigate other possible large-scale applications around Singapore.