The advancement in water treatment technology has revolutionized the progress of membrane bioreactor (MBR) technology in the modern era. The large space requirement, low efficiency, and high cost of the traditional activated sludge process have given the necessary space for the MBR system to come into action. The conventional activated sludge (CAS) process and tertiary filtration can be replaced by immersed and side-stream MBR. This article outlines the historical advancement of the MBR process in the treatment of industrial and municipal wastewaters. The structural features and design parameters of MBR, e.g., membrane surface properties, permeate flux, retention time, pH, alkalinity, temperature, cleaning frequency, etc., highly influence the efficiency of the MBR process. The submerged MBR can handle lower permeate flux (requires less power), whereas the side-stream MBR can handle higher permeate flux (requires more power). However, MBR has some operational issues with conventional water treatment technologies. The quality of sludge, equipment requirements, and fouling are major drawbacks of the MBR process. This review paper also deals with the approach to address these constraints. However, given the energy limitations, climatic changes, and resource depletion, conventional wastewater treatment systems face significant obstacles. When compared with CAS, MBR has better permeate quality, simpler operational management, and a reduced footprint requirement. Thus, for sustainable water treatment, MBR can be an efficient tool.

A microbial fuel cell (MFC) is a system that can generate electricity by harnessing microorganisms’ metabolic activity. MFCs can be used in wastewater treatment plants since they can convert the organic matter in wastewater into electricity while also removing pollutants. The microorganisms in the anode electrode oxidize the organic matter, breaking down pollutants and generating electrons that flow through an electrical circuit to the cathode compartment. This process also generates clean water as a byproduct, which can be reused or released back into the environment. MFCs offer a more energy-efficient alternative to traditional wastewater treatment plants, as they can generate electricity from the organic matter in wastewater, offsetting the energy needs of the treatment plants. The energy requirements of conventional wastewater treatment plants can add to the overall cost of the treatment process and contribute to greenhouse gas emissions. MFCs in wastewater treatment plants can increase sustainability in wastewater treatment processes by increasing energy efficiency and reducing operational cost and greenhouse gas emissions. However, the build-up to the commercial-scale still needs a lot of study, as MFC research is still in its early stages. This study thoroughly describes the principles underlying MFCs, including their fundamental structure and types, construction materials and membrane, working mechanism, and significant process elements influencing their effectiveness in the workplace. The application of this technology in sustainable wastewater treatment, as well as the challenges involved in its widespread adoption, are discussed in this study.

The aim of this research is to investigate the shrinkage properties of cotton polyester spandex denim fabrics of different fiber content. Cotton fabrics with spandex have a tendency to shrink when it comes in contact of water. Cotton spandex shrinks more when it comes in contact of hot water. Cotton is swelled up in water; thereby increase the width of fibers, as a result there is the decrease of length. If the cotton composition with spandex increases, the shrinkage property of fabric also increases. The higher the percentage of spandex content in a fabric is, the higher the value of shrinkage is. On the other hand, polyester does not shrink when it comes in contact of water, as manmade polyester fiber does not swell up in water. Three specimen of cotton polyester spandex denim fabrics of different fiber content were used in this research. Finished fabrics were collected from fabric mills for conducting the required shrinkage test with the standard specified by AATCC Test Method 135. This research is practice based and the discoveries are advantageous to the textile professionals. This research proved that the properties of shrinkage depends on the fiber content of cotton polyester spandex denim fabrics and it showed a suitable way for the scholars to further study in this field.

In the past few years, a number of incidents related to fire and explosions in temporary chemical storage facilities have occurred that have resulted in large numbers of casualties. This includes explosions at a warehouse near Tianjin Port, China, in 2015 and that at a warehouse facility storing ammonium nitrate at Beirut port, Lebanon, in 2020. Very recently, a similar incident occurred in a container depot in Bangladesh. On June 4, 2022, a massive fire broke out at BM Inland Container Depot, a temporary storage facility in the town of Sitakunda, Bangladesh. The fire and subsequent explosions resulted in at least 48 fatalities, including 10 firefighters, and injured more than 200 people. The fire, which took 86 h to completely extinguish, has resulted in financial losses of more than US$152 million according to authorities. In this paper, an investigative consequence analysis of the accident is presented with the goals to identify the possible reasons that culminated in the catastrophe, quantify the magnitude of the explosion, and explore the key lessons learned. This work also sheds light on the existing local legislation and international guidelines relating to the storage of hazardous materials. Furthermore, human and social consequences of an accident similar in magnitude have been assessed for two other inland container depots. This work, thus, may be considered a scientific exercise aimed at creating awareness of the gravity of accidents in temporary storage facilities and a lesson learned to prevent such catastrophes in the future.

The paper presents a computationally efficient approach to develop a nonlinear data driven input/output model between the finite-time control trajectories and the quality index at the end of the batch. Polynomial chaos expansion (PCE) was applied to produce the approximate representation of the full process model of a nonlinear batch reactor with the reaction scheme .A-->k1B--> k2C A surrogate model was developed to estimate the dependence of intermediate product (B) concentration at the end of the batch on the temperature trajectory applied during the reaction. The surrogate model was then validated for its performance. Later, the surrogate model was used to determine the optimal temperature profile needed to maximize the concentration of intermediate product at the end of the batch. The validation and optimization results prove that the experimental data based PCE can provide a very good approximation of the desired outputs, providing a generally applicable approach for rapid design, control and optimization of batch reactor systems. Chemical Engineering Research Bulletin 21(2020) 121-126