Yes / The integration of two or more processes in a hybrid system is one of the most desirable options to provide flexibility, interoperability and data sharing between the connected processes. Various examples of hybrid systems have been developed with coherent seawater desalination systems such as the combination of thermal and membrane technologies. This paper focuses on the simulation and optimisation of an integrated (hybrid) system of multi effect distillation and double Reverse Osmosis (RO) processes to produce different grades of water needed in a smart city from seawater resources. The optimisation-based model investigates five scenarios to obtain the highest productivity of drinking water, irrigation water, water for livestock and power plant water, whilst constraining the product water salinity to be within the required standards and with lowest specific energy consumption. For this purpose, multi objective optimisation problem was formulated using the gPROMS (general Process Modelling System) software. The results confirm the superiority of the developed hybrid system to sustain different grades of water in a smart city.

Yes / In recent times two or more desalination processes have been combined to form integrated systems that have been widely used to resolve the limitations of individual processes as well as producing high performance systems. In this regard, a simple integrated system of the Multi Effect Distillation (MED)/Thermal Vapour Compression (TVC) and Permeate Reprocessing Reverse Osmosis (PRRO) process was developed by the same authors and confirmed its validity after a comparison study against other developed configurations. However, this design has a considerable amount of retentate flowrate and low productivity. To resolve this issue, two novel designs of MED and double reverse osmosis (RO) processes including Permeate and Retentate Reprocessing designs (PRRP and RRRO) are developed and modelled in this paper. To systematically assess the consistency of the presented designs, the performance indicators of the novel designs are compared against previous simple designs of MED and PRRO processes at a specified set of operating conditions. Results show the superiority of the integrated MED and double permeate reprocessing design. This has specifically achieved both economic and environmental advantages where total productivity is increased by around 9% and total retentate flowrate (disposed to water bodies) is reduced by 5% with a marginally reduced energy consumption.