Rice husk ash as a sustainable and economical alternative to chemical additives for enhanced rheology in drilling fluids.

Performance evaluation of drilling fluids is essential for a successful drilling project, as they not only remove drill cuttings but also prevent undesired penetration or outflow of formation fluids by sealing off wellbore walls. However, concerns have been raised about the use of chemical additives in drilling fluids due to their toxicity and non-biodegradability. To this end, agricultural waste materials are recognized as a promising alternative as they are cost-effective, environmentally sustainable, and can be used as a substitute for lost circulation materials. Rice husk ash (RHA) has become popular as an additive due to its renewable characteristics, including its large surface area, silica content, and microporous structure. This research article explores the rheological properties of drilling fluid with RHA as a filter control medium. The results showed that increasing concentrations of RHA in the drilling mud significantly improved its rheology, particularly at higher concentrations (15 and 20 wt.%). The addition of RHA modified the filtration and rheological properties of the drilling mud, resulting in improved plastic viscosity, yield point, density, gel strength, and thixotropy. However, filter loss and mud cake thickness increased at elevated RHA concentrations. Furthermore, the pH test revealed that the mud's properties shifted toward the acidic region as the RHA concentration increased. The results indicate that RHA could be used as a sustainable and cost-effective alternative to conventional chemical additives with a positive environmental impact. This study may also provide valuable insights into the use of RHA in water-based bentonite mud and could serve as a guide for future research in the drilling industry.

Recent advances in dynamic modeling and control studies of biomass gasification for production of hydrogen rich syngas.

The conversion of biomass through thermochemical processes has emerged as a promising approach to meet the demand for alternative renewable fuels. However, these processes are complex, labor-intensive, and time-consuming. To optimize the performance and productivity of these processes, modeling strategies have been developed, with steady-state modeling being the most commonly used approach. However, for precision in biomass gasification, dynamic modeling and control are necessary. Despite efforts to improve modeling accuracy, deviations between experimental and modeling results remain significant due to the steady-state condition assumption. This paper emphasizes the importance of using Aspen Plus® to conduct dynamics and control studies of biomass gasification processes using different feedstocks. As Aspen Plus® is comprising of its Aspen Dynamics environment which provides a valuable tool that can capture the complex interactions between factors that influence gasification performance. It has been widely used in various sectors to simulate chemical processes. This review examines the steady-state and dynamic modeling and control investigations of the gasification process using Aspen Plus®. The software enables the development of dynamic and steady-state models for the gasification process and facilitates the optimization of process parameters by simulating various scenarios. Furthermore, this paper highlights the importance of different control strategies employed in biomass gasification, utilizing various models and software, including the limited review available on model predictive controller, a multivariable MIMO controller.

Investigation of textile dyeing effluent using activated sludge system to assess the removal efficiency.

In this current work, the performance of an aerobic granular sludge (AGS) for real textile wastewater was investigated based on system operational parameters evaluation. The study was performed for 90 days, and sampling was done once a week in which textile dyeing effluent from the textile mill was collected and subjected to laboratory-scale treatment. The samples from the inlet, the outlet of the wastewater plant, and within the bioreactor were collected at various concentrations of mixed liquid suspended solids (MLSS), and hydraulic retention remained the same in the investigated period of 53 h. The objective of this study was to analyze the AGS system performance assessment by evaluating the effect of different MLSS concentrations on chemical oxygen demand (COD), total suspended solids (TSS), and oil/grease removal from real-based textile water. The results showed that removal of organic material from the process water increases with an increase in MLSS concentration in the bioreactor and gradually shifts removal of COD from 91.2% to 94.5%. As the concentration of microorganisms in the reactor (aeration tank) increases, the degradation of waste organics in the wastewater increases as well. Moreover, the % removal of TSS (83.5% to 98%) and removal of oil/grease (62.5% to 76.4%) were also increased. These results ultimately suggest that the utilization of an activated sludge system can effectively treat complex and highly polluted denim textile wastewater to avoid secondary pollution posed by this industry. PRACTITIONER POINTS: The effectiveness of aerobic granular sludge was investigated for industrial textile effluent. The increase in MLSS results in increase of % COD removal efficiency to 94.5%. The AGS system can efficiently treat complicated and highly contaminated textile wastewater.