Recycling of Cement–Wood Board Production Waste into a Low-Strength Cementitious Binder

Abstract

Cement is a widely used building material, with more than 4.4 billion metric tons produced in 2021. Unfortunately, the excessive use of cement raises several environmental issues, one of which is the massive amounts of CO2e produced as a by-product. Using recycled materials in the concrete mix is widely employed to solve this problem. A method for minimizing the use of natural cement by substituting it with secondary cementitious material that consists of wood–cement board manufacturing waste has been studied in this paper. The cement in the waste stream was reactivated by a mechanical treatment method—the use of a planetary mill, allowing it to regain its cementitious properties and be used as a binder. Physical and mineralogical analysis of the binder material was performed using X-ray diffraction (XRD), thermogravimetry/differential thermal analysis (TG/DTA) and Brunauer–Emmett–Teller analysis; granulometry and compressive strength tests were also carried out. The results show that the grinding process did not significantly change the mineralogical composition and the specific surface area; it did, however, affect the compressive strength of the samples prepared by using the reactivated binding material; also, the addition of plasticizer to the mix increased compressive strength by 2.5 times. Samples were cured in high-humidity conditions. The optimal water-to-binder (W/B) ratio was found to be 0.7 because of the wood particles that absorb water in their structure. Compressive strength increased as the grinding time increased.

Modified Lignocellulosic Waste for the Amelioration of Water Quality: Adsorptive Removal of Congo Red and Nitrate Using Modified Poplar Sawdust

“…Generally, the porosity of the analysed sample is low; this is in accordance with the nature of the sample, wood scraps, which present a material made of tiny tracheae and tracheids that carry food through the plant. Also, the value of the specific surface area determined by mercury intrusion porosimetry is very low, which is in agreement both with the value of the total porosity and with the size of the pores that prevail in the analysed sample [30]. The PSD curves (Figure 3) indicate the macropore nature of the analysed sample, the maximum sizes of which are centred at diameters between 7 and 9 µm.…”

Development of New Bio-Based Building Materials by Utilising Manufacturing Waste

“…Reusing cement-based materials, such as concrete, can also help conserve natural resources [7] and reduce the construction industry's waste [8]. To address these issues, reactivating cement has gained traction to reduce waste and make the construction industry more sustainable [9]. Reactivating cement involves using leftover or waste cement in new construction projects instead of producing new cement from raw materials, thereby reducing the construction industry's carbon footprint, conserving natural resources, and minimising waste [10], [11].…”

“…Reactivating cement involves using leftover or waste cement in new construction projects instead of producing new cement from raw materials, thereby reducing the construction industry's carbon footprint, conserving natural resources, and minimising waste [10], [11]. There are several options for recycling cement and concrete, including using them as aggregates [12], [13] in new concrete production, using them as binders [9], [14], [15], and using them as raw materials in the production of blended cement [16]- [19].…”

“…Recycling and incorporating the processing waste into other applications would be more cost-effective than disposing of it in a landfill because it is made of the same materials as the primary manufacturing product. This study explores the possibility of using a previously developed binder [9], [14] and filler from a manufacturing waste stream to make building materials. The new binder would be an environmentally friendly alternative to traditional cement, as it is a manufacturing waste and can reduce the manufacturer's carbon footprint.…”

Advancing the Circular Economy: Reusing Hybrid Bio-Waste-Based Gypsum for Sustainable Building Insulation

“…Additionally, the use of these binders has a detrimental impact on the environment, for instance. Cement production is responsible for 8% of greenhouse gas emissions [16]. An amount of 900 kg of CO 2 is produced in one ton of cement production.…”