Journal of Engineering

Dairy wastewater generally contains fats, lactose, whey proteins, and nutrients. Casein precipitation causes the effluent to decompose into a dark, strong-smelling sludge. Fluid waste contains soluble organic matter, suspended solids, and gaseous organic matter, which cause undesirable taste and smell, grant tone and turbidity, and advance eutrophication, which plays an essential role in increasing biological oxygen demand (BOD) in water. It also contains detergents and disinfecting agents from the rinses and washing processes, which increase the need for chemical oxygen (COD). One of the characteristics of dairy effluents is their relatively high temperature, high organic contents, and wide pH range, so the discharge of wastewater into water bodies without treatment leads to deterioration of water quality and ecological imbalance, and therefore treatment is required. To remove or reduce environmental damage. Dairy wastewater treatment includes mechanical, physical, chemical, and biological methods. Organic treatment techniques are reasonable for treating wastewater from the dairy business because of their high biodegradability. Notwithstanding, the long-chain unsaturated fats formed during lipid hydrolysis show an inhibitory impact during anaerobic treatment. Chain block reactors (SBR) and top stream anaerobic slop cover of sludge (UASB) systems are the most encouraging advancements for the organic treatment of dairy wastewater. Many papers have applied high-impact exercise and technical methods to the dairy business's anaerobic wastewater treatment of dairy wastewater. However, the two techniques actually have a few disadvantages. The most vital objective of these studies is to track down savvy and naturally manageable ways to deal with and enable the reuse and management of wastewater and waste. Consequently, elective treatments to organic treatment are physical and substance techniques, for example, coagulation, retention, layer cycles, and electrolysis. This section provides a primary survey zeroing in on physical and compound treatment strategies for dairy wastewater treatment. It is under study and checked for its viability.

This review explores the environmental and practical benefits of recycling crushed clay bricks (CCB) for use in load-bearing concrete masonry units. The study highlights the significant quantities of waste clay bricks generated from building demolitions and the potential to reduce environmental impact by recycling these materials. The review discusses replacing coarse aggregates and cement with varying percentages of CCB, evaluating the resulting physical and mechanical properties such as workability, dry density, compressive strength, thermal conductivity, and absorption. Experimental results confirm the feasibility of using recycled CCB as a sustainable alternative to natural aggregates, reducing weight and enhancing the mechanical properties of concrete masonry units.

This study evaluates the effectiveness of Adaptive Neuro-Fuzzy Inference System (ANFIS) and regression techniques in estimating the soil compression index (Cc) for cohesive soils. Direct measurement of Cc is expensive and time-consuming, so indirect methods using variables like liquid limit, soil density, and natural water content are preferred. The study collected 177 undisturbed soil samples from Sulaymaniyah Governorate, Iraq. Results showed that ANFIS models outperformed regression models, with R² values of 0.66 and 0.48, respectively. This research demonstrates the potential of machine learning techniques for cost-effective and robust Cc estimation.

This study investigates the mechanical properties of reactive powder concrete (RPC) containing recycled glass powder. The research explored the effect of partial replacement of cement with recycled glass powder at two percentages (0%, 20%) by weight of cement. The study also included the use of 1% micro steel fibers and steam curing at 90°C for 5 hours. The results showed significant improvements in properties such as fresh density, splitting tensile strength, impact strength, and voids percentage. Specifically, the fresh density increased by 7.27%, splitting tensile strength increased by 23.5% at 28 days, and the voids percentage decreased by 12.5% at 28 days compared to the reference mixture.

This study analyzes the effect of thermal conductivity of phase change material (PCM) on the performance of thermal energy storage (TES) systems. A horizontal concentric shell-and-tube latent heat thermal energy storage system (LHTESS) was modeled during the solidification process. Two types of paraffin wax with different melting temperatures and thermal conductivities were used as PCM on the shell side. Water was used as the heat transfer fluid (HTF) flowing through the tube side. The simulation was conducted using ANSYS Fluent, considering phase change by the enthalpy method. The results showed that increasing the thermal conductivity of PCM reduced the solidification time by 20%. The performance of LHTESS for the higher thermal conductivity PCM was 63.2%, compared to 54.6% for the lower thermal conductivity PCM.

This study uses the finite element method to investigate the behavior of precast reinforced concrete dapped-end beams (DEBs) numerically. A parametric investigation was performed on an experimental specimen tested by a previous researcher to show the effect of numerous parameters on the strength and behavior of RC dapped-end beams. Parameters such as reinforcement details, steel arrangement, concrete compressive strength, inclined load, and support settlement were examined. The results revealed that the dapped-end reinforcement arrangement greatly affects the behavior of dapped-end beams. The failure load decreases by 25% when insufficient development length for main dapped-end reinforcement is provided, and nib shear reinforcement has less effect than nib main reinforcement. The results also showed that the shear strength of dapped-end beams increased as concrete strength increased. When the compressive strength of concrete increased by 100%, the strength capacity enhanced by about 34%. The strength of the dapped-end beams is significantly affected by the settlement of the supports.