Lower Rio Grande Valley Tap Water Hardness Removal Using Conductive Concrete Cathode in Electrochemical Precipitation

Electrochemical water softening has obtained significant attention in recent years due to being environmentally friendly. One of this method\u27s significant problems is the requirement of high cathodic surface area for enough efficiency. As most electrochemical cells use costly metal cathodes with meager service life and low structural integrity, practical large-scale implementation is scarce. In this research, graphite-concrete cathodes were proposed to replace conventional metal cathodes in the electrochemical water softening process. Graphite concrete has been used for heating pavement and electrical conductive roads. In this research concrete mixed with graphite powder by volume was successfully used as a cathode to treat LRGV(Lower Rio Grande valley) tap water. In this Electrochemical precipitation process, the total removal efficiency was achieved up to 53% at 35.5 Volt with a retention time of 60 minutes and an interelectrode distance of .5cm. The 10% graphite-concrete cathodes were responsible for this performance the decent efficiency suggested that graphite concrete cathodes are viable alternatives to metal ones in hardness removal from tap water. Also, optimal performance parameters such as inter electrode distance, material and retention times were discovered. In this research it was concluded that with perfect conditions, conductive concrete can be used as structural material. Furthermore, it can provide efficient and effective water hardness treatment for the topwater. Further research is needed on flowing water and heavy metal removal to know the trye potential of this electrochemical precipitation method

Comprehensive Analysis of the Effects of Superplasticizer Variation on the Workability and Strength of Ready-Mix Concrete

This experimental study aims to examine the influence of many crucial parameters on the workability and compressive strength of Ready-Mix Concrete (RMC). The study utilized two distinct varieties of superplasticizers obtained from the local market. The fine aggregates utilized in this study were sourced from Sylhet sand, whereas the coarse aggregates were comprised of boulder crushed stone chips. The experimental procedures adhered to the requirements outlined by ASTM. A comprehensive investigation was conducted on a range of concrete compositions that used diverse chemical admixtures. The slump test was performed at regular intervals of 15 minutes until the slump value reached or fell below 3 cm after the mixing of the concrete. In the scenario involving two-stage admixture dosage, the second stage of admixture was introduced once the slump reached or dropped below 3 cm, following which the casting process was initiated. The process of curing concrete specimens consists of two distinct stages: the main stage and the final stage. Cylindrical specimens, with a diameter of 4 inches and a height of 8 inches, were manufactured for the purpose of evaluating their compressive strength at both 7 and 28 days. During the experimental trials, the water-cement (w/c) ratio was kept consistent, while different dosages of admixture were applied. The findings of the study indicate that the utilization of a two-stage dose of admixture resulted in enhanced and extended workability, along with higher strength of the concrete in comparison to specimens that did not incorporate any admixture. This research study enhances the comprehension of optimizing qualities of ready-mix concrete (RMC) by varying the superplasticizer, providing useful insights for the building sector

The Potential of Cattle Manure Microbiome in Degrading Plastics

Plastics are widely used in modern society. How to handle plastic wastes presents a major environmental challenge. In this thesis we explored the potential of plastic biodegradation. The objectives of this research were to (1) examine the potential of cattle manure microbiome in anaerobically degrading various types of plastics; (2) characterize the surface modifications on plastics caused by pretreatment and biological treatment. Five types of plastics were included in this research, polypropylene (PP), polyethylene terephthalate (PET), low- and high-density polyethylene (LDPE and HDPE), and polyhydroxybutyrate (PHB). Results show that cattle manure microbiome could achieve specific surface degradation rates (SSDR) as high as 4.3 mm/year for PHB, a biodegradable plastic, with no obvious benefits from UV or thermal pretreatment. For the other plastic types, the microbiome could achieve SSDR as high as 22.0 μm per year for HDPE, 27.7 μm per year for LDPE, and 64.7 μm per year for PP. No mass reduction was observed for PET. For PP, LDPE, and HDPE, the UV and thermal pretreatment enhanced the biological treatment by cattle manure microbiome. In general, the SSDR rates achieved in this study are higher than those summarized in a recent review paper, demonstrating the superior ability of the microbiome in beef cattle manure in degrading complex molecules. According to gel permeation chromatography (GPC), the reductions in the molecular weights of molecules on plastic surfaces are commensurate to the SSDR results. Results from Fourier-Transform Infrared Spectroscopy (FTIR) further illustrate the functional groups on plastic surfaces that were altered by pretreatment and biological treatment. The overall findings demonstrate the potential of beef cattle manure as a source of microbes to biodegrade plastics. Advisor: Xu L