Hydration, Strength, and Shrinkage of Cementitious Materials Mixed with Simulated Desalination Brine

Abstract

The process of desalination results in the production of a hypersaline waste by-product known as reject brine. In some locations, this reject brine is dumped back into the ocean, which has potentially detrimental effects on water quality and marine life. This study was carried out to investigate whether this brine could potentially be used to manufacture cementitious materials. The effects of different concentrations of simulated reject brine on hydration kinetics, compressive strength, and drying shrinkage of cement paste and mortar were investigated. Cement paste and mortars were prepared using a water-to-cement ratio of 0.45 and were mixed with simulated reject brine, tap water, and diluted reject brine (an equal mass mixture of reject brine and tap water). The results show that the reject brine causes an acceleration of early cement hydration; however, this effect is negligible at later ages. Mixtures containing reject brine have higher compressive strength at early ages, although this difference is reduced at 91 d. The reject brine causes a drastic increase in the drying shrinkage. The difference between the results obtained using reject brine and diluted reject brine were generally insignificant, which suggests that the effects of solution composition on the observed properties were not strong when solution concentrations were greater than a threshold value. Although these results are preliminary and further feasibility studies, including research on concrete durability, are required, the results suggest that reject brine may be used to make unreinforced concrete or concrete reinforced with noncorrosive materials.

A review of recent advances in the science and technology of seawater-mixed concrete

“…The authors showed acceleration of hydration in the presence of these salts/seawater, formation of Friedel's salt in the presence of chloride, and increased early-age strength. Findings from modeling are consistent with the experimental results from other studies [2][3][4]11,[18][19][20][21][22].…”

Evaluation of modulus of elasticity for eco-friendly concrete made with seawater and marine sand

“…Research has also been conducted to study the effect of marine sand and seawater on the quality of conventional reinforced concrete. Some researchers have stated that the hydration process in concrete was affected due to the presence of chemical ions in seawater [22][23][24][25][26][27][28][29][30], others concluded that the highlevel presence of chloride in marine sand and seawater could lead to the corrosion of reinforcing steel in concrete [26,27]. The influence of saltwater on setting time and strength enhancement was also reported in several studies [28,29].…”

Effect of polymer content and temperature on mechanical properties of lightweight polymer concrete

“…Over the last decades, finding novel efficient, cost-effective, and eco-friendly solutions on the development of new infrastructures has become of prime importance [1,2]. The requirement of having energy efficient buildings necessitates the development of new materials and improvement of existing materials and lightweight structures [3][4][5].…”