Comparative life cycle assessment of reactive MgO and Portland cement production

Influence of Waste Plastic Aggregate and Water-Repellent Additive on the Properties of Lightweight Magnesium Oxychloride Cement Composite

“…volume of CO 2 emissions can be attributed to building industry, whether related to construction materials production or energy needed for heating and cooling of insufficiently insulated buildings [1,2]. For example production of Portland cement (PC) contributes to circa 5-7% of the global CO 2 emissions [3,4].At present, there are efforts to find an alternative to PC that would have a low carbon footprint. One of the candidates may be cements based on the magnesium oxide (MgO).…”

“…Magnesium oxychloride cement (also known as Sorel cement) is formed by the reaction of a light-burnt MgO powder with a solution of magnesium chloride (MgCl 2 ) [5], where the light-burnt (also called caustic c) MgO is produced by calcination of magnesite (MgCO 3 ) at a temperature of circa 750 • C [6]. This lower temperature, compared to~1450 • C used in the production of Portland clinker, allows the use of alternative fuels [3]. MOC cement-based composites are able to absorb high amount of CO 2 from the atmosphere during their service life to form carbonates and hydroxycarbonates, which leads to their denser microstructure and to higher strength of resulting material [4,7].…”

“…MOC cement-based composites are able to absorb high amount of CO 2 from the atmosphere during their service life to form carbonates and hydroxycarbonates, which leads to their denser microstructure and to higher strength of resulting material [4,7]. The production of MgO from magnesite releases more CO 2 per ton than in the production of Portland cement (1.7 t of CO 2 /t of MgO vs. 1 t CO 2 /t of PC) [3]. However, taking into account the carbonation of the MOC cement composites, when MOC is able to sequestrate more than half of the CO 2 produced during MgCO 3 calcination (the resulting CO 2 emissions decreased therefore to around 0.5-0.6 t of CO 2 /t), and given the total environmental impact during the life cycle of MgO ascertained by LCA, the MOC cement can be considered as environmentally friendly material [3].Among superior properties of MOC cement composites are: early compressive strength, excellent fire resistance, low alkalinity (pH of 8-10), short setting time, and anti-abrasion performance [8,9].…”

“…The production of MgO from magnesite releases more CO 2 per ton than in the production of Portland cement (1.7 t of CO 2 /t of MgO vs. 1 t CO 2 /t of PC) [3]. However, taking into account the carbonation of the MOC cement composites, when MOC is able to sequestrate more than half of the CO 2 produced during MgCO 3 calcination (the resulting CO 2 emissions decreased therefore to around 0.5-0.6 t of CO 2 /t), and given the total environmental impact during the life cycle of MgO ascertained by LCA, the MOC cement can be considered as environmentally friendly material [3].Among superior properties of MOC cement composites are: early compressive strength, excellent fire resistance, low alkalinity (pH of 8-10), short setting time, and anti-abrasion performance [8,9]. MOC cements are also known by their ability to incorporate a higher amount of various fillers compared to PC, namely granite waste [10], fly ash [10,11], cenospheres derived from the fly ash [12], biomass ash [13], wood [6], recycled tire rubber [14], and waste plastics [15].…”

An Investigation of PM 2.5 from Regional Industries in Chengdu, China

“…Currently, PM 2.5 emissions from the tiles industry are mainly from coals burned in the kilns and from dust (Skinder et al, 2014). Dust is accompanied with preparation of raw materials, calcination, and the manufacturing process (Ruan and unluer, 2016 Figure 12 shows the spatial distribution of PM 2.5 emissions from the glass industry in Chengdu. The amounts of glass produced in Shuangliu and Qing Baijiang respectively account for 46.35% and 34.76% of the total.…”