盐耦合侵蚀下碱矿渣水泥相演变的热力学模拟

Thermodynamic parameters of chloride and sulfate intercalated hydrotalcites were deduced. The phase evolutions in alkali‑activated slag cement upon only sodium chloride or only magnesium sulfate attack and combined attack of those two salts were investigated via thermodynamic modelling. Friedel's salt was predicted to form under sodium...

Plasters with mixed-in crystallization inhibitors: Results of a 4-year monitoring of on-site application

Salt crystallization is a major cause of weathering of mortars, including plasters and renders. In the last decade, the use of mixed-in salt crystallization inhibitors in mortars has been proposed as a solution to improve the durability of this material with respect to salt decay. Laboratory characterization and accelerated weathering tests have...

A new accelerated salt weathering test by RILEM TC 271-ASC: preliminary round robin validation

Salt crystallization is a major cause of damage in porous building materials. Accelerated salt weathering tests carried out in the laboratory are among the most common methods to assess the durability of material to salt decay. However, existing standards and recommendations for salt weathering tests have limitations in terms of effectiveness...

NaCl interaction during hydration as studied by NMR

With freshwater getting scares seawater, i.e., water containing NaCl, can become the only viable option for making concrete. Although a lot of research had been directed to understanding the role of water in cement hydration, not much is known about the interaction of the Na+ and Cl- with cement paste during drying. A problem is that available...

Effect Of Alkali Ferrocyanides On Crystallisation Of Sodium Chloride: Preliminary results

Sodium chloride (NaCl) is one of the ubiquitous soluble salts in the environment and is responsible for weathering of building materials. The salt weathering is attributed to the stress developed from crystallisation of these salts in pores of the building materials, with supersaturation as the driving force. In the last years, researchers have...

Effect of sodium chloride on the formation of ice and salt during eutectic freeze crystallization of sodium sulfate with a scenario study of real brine

Brine streams from industry is a burden to the environment if not disposed properly. “Zero liquid discharge” (ZLD) is an ideal way of converting saline streams from waste to resource through multiple membrane-based or thermal-based treatment technologies. The utilization of the recovered resource minimizes both costs and environmental impacts....

Product characteristics in simultaneous crystallization of NaCl and CaSO₄ from aqueous solution with seeding

Zero liquid discharge strategies for industrial wastewater treatment have become prominent in recent years. When evaporative simultaneous crystallization is applied, knowledge about the particle crystallization mechanisms and morphology are important to ease solids downstream handling and for recovery of their valuable components. In this...

Ceramic Nanofiltration Of NOM Rich Brine

The presence of organic and inorganic contaminants in aquatic ecosystem has been threat to public health and environment. To produce drinking water, removal of natural organic matter has been of importance due to formation of DBPs. Of the many available treatments, ion exchange (IEX) has the potential to remove natural organic matter (NOM)....

Effect of mixed in crystallization modifiers on the resistance of lime mortar against NaCl and Na₂SO₄ crystallization

Weathering of porous building materials caused by the crystallization of soluble salts is a ubiquitous problem in the built cultural heritage. Especially lime-based mortars are susceptible to salt decay, due to both their bimodal pore size distribution and low mechanical strength. The addition of crystallization modifiers to mortars during...

Predicting salt damage in practice: a theoretical insight into laboratory tests

Salt crystallization represents one of the major causes for the degradation of building and ornamental stone. As such, it has attracted the attention of researchers, who over the years have progressively unraveled most mechanisms involved in salt damage. Despite this mechanistic understanding, many questions subsist about how to quantitatively...

Sodium chloride recovery from brines for reuse purposes in zero liquid discharge

In the application of the Zero Liquid Discharge (ZLD) strategy, not a single drop of water leaves the waste water treatment plant (WWTP). In the recovery strategy of an actual full-scale ZLD WWTP, the focus lies on high quality water, which is fully recovered from reverse osmosis brine (RO-brine). A residual solid stream is generated and...

Furfural synthesis from D-xylose in the presence of sodium chloride: Microwave versus conventional heating

We investigate the existence of specific/nonthermal microwave effects for the dehydration reaction of xylose to furfural in the presence of NaCl. Such effects are reported for sugars dehydration reactions in several literature reports. To this end, we adopted three approaches that compare microwave-assisted experiments with a) conventional...

Stress corrosion crack initiation testing of high strength aluminium alloys using tuning fork type specimens

An experimental investigation was carried out into the applicability of various corrosive environments for stress corrosion crack initiation testing of high strength aluminium alloys using constant strain loaded tuning fork type specimens. The effect of surface preparation was also involved. The most important findings were that salt-chromate...

Environmental fatigue crack propagation in Ti-6A1-4V sheet: Revised Edition

A study was made of environmental fatigue crack propagation in 2.5 mm thick Ti-6A1-4V sheet conforming to AMS 4911, and 2.2 mm thick IMI 3l8 conforming to BS TA 10. The environments were dry argon, normal air, distilled water and 3.5 ^ aqueous NaCl. There were three alloy/orientation combinations: Ti-6A1-4V L-T, IMI 3l8 L-T and IMI 318 T-L. Test...