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The aim of this study was to investigate the microbial quality of drinking water distributed through water dispenser machines located in schools and universities in Ajman, UAE. In total, 49 drinking water samples were collected from water dispenser machines in the schools and university's premises in the emirate of Ajman. Total coliform and E.coli were detected using Colilert test. P. aeruginosa colonies were counted on Pseudomonas agar using the membrane filtration method. Overall, 25 out of total 49 samples were found to contain either P. aeruginosa, or total coliform or both. Six samples were found positive for total coliform group members, whereas nineteen of the samples were positive for P. aeruginosa. Ten water samples were found positive for both total coliform and P.aeruginosa. P.aeruginosa colonies count ranged between 4 to 51 colonies per 250 ml of water sample. In conclusion, overall microbiological quality of 25 drinking water samples distributed through the water dispenser machine was found unsatisfactory, and this could be attributed to the poor maintenance and improper hygienic conditions of water dispenser machines. In order to safeguard public health, more efforts such as community awareness program, strict regulations such as regular inspections by the local municipalities are needed.Index Terms-Microbiological quality, drinking water, water dispenser.

Ultra-high-purity propylene glycol monomethyl ether acetate (PGMEA) is required as an electronic-grade solvent to meet the stringent requirements of the rapidly developing semiconductor industry. The high demand for ultra-high-purity PGMEA has created the need for an efficient sustainable process for reducing energy consumption as well as satisfying tight waste management regulations. Here, a potentially sustainable and novel process for efficient continuous electronic-grade PGMEA manufacturing is presented. This study covers the extensive design of the novel PGMEA manufacturing process and its intensification from the conceptual level to rigorous simulation. The base case of the proposed PGMEA manufacturing process highlights the feasibility of renewable resource use, single ultra-high-purity PGMEA, nonrequirement of an additional solvent, less waste generation, and reduction in the usage of raw materials. The advanced intensification of PGMEA manufacturing by exploiting reactive pressure-swing distillation achieves total reduction in energy, cost, and CO2 emissions of approximately 38.65, 35.05, and 36.25%, respectively, compared to the base case with rigorous optimal reactive distillation and pressure-swing distillation. Furthermore, heat integration of intensified case reduced the total heat utility by 47.27%.