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•An innovative plant configuration for the DME production is assessed.•The plant is composed by a membrane reactor and a Double Recycling Loop.•The study is based on MatLab+Aspen modeling.•A microporous zeolite membrane is assembled inside the DME synthesis reactor.•Reactor performance improves at high CO2 content in the feedstock.

Among the thermal desalination process, the humidification-dehumidification (HDH) is quite energy demanding due to the presence of circulating air (as water carrier from the saline source to the condensation unit) that increases the required interface areas. Nevertheless, this process shows many unique attributes that are pushing a recent revival of R&D in the field of small-scale solar desalination. Within this framework, we believe in the importance of developing solutions for decentralized production in rural remote areas and suggest an innovative process scheme of HDH with brine recirculation. This process assumes the multiple extractions for the minimization of entropy generation and the internal recirculation of brine, in order to cut the cost of seawater pretreatment and the related environmental impacts. The multiple extraction HDH tower with partial rejection of heat and seawater introduces a new concept in the HDH panorama: the closed-air closed-water (CACW). The process scheme of the HDH with brine recirculation and the related mathematical model are presented in the paper. The degrees of freedom of the process and the way to fix the main parameters under conservative assumptions, are discussed in the following. Moreover, the preliminary results of a sensitivity analysis (such as the condenser surfaces and packing tower height) are shown. Although the paper presents the way to drastically improve the theoretical performances of HDH, a solution with acceptable operating costs and mild operating conditions is presented: the arrangement with three extractions and one stage of condensation (~10 m of humidification and dehumidification parallel towers) for an installed capacity of 50 m3/day, has a GOR of 3 and a RR of 50% at a maximum process temperature of 65°C.

An innovative concept for steam methane reforming (SMR), based on reformer and membrane modules (RMMs), has been developed and tested to investigate its performance, in terms of feed conversion, on an industrial scale. A major benefit of the proposed RMM configuration is a shift of the chemical equilibrium of SMR reactions, achieved by removing the hydrogen produced at high temperature through the integration of highly selective palladium‐based membranes, which enhances the yield of product. In this manner the process can operate at temperatures as low as 600–650 °C, compared to the 850–880 °C range used in conventional plants, and allows for the use of a low‐temperature heat source. This Full Paper discusses experimental data on feed conversion at different operating parameters, gathered during 1000 h of testing, and processes these data to optimize the overall architecture, defining the maximum achievable feed conversion. An overall conversion of 59 % is achieved with two‐step reactions at a reforming temperature of 620 °C. A conversion as high as 90 % can be obtained with a three‐step architecture at 650 °C by properly extending the design parameters within reasonable limits.

Water-gas shift reaction is an important industrial reaction, used for producing synthesis gas and ammonia as well as pure hydrogen for supplying at PEM fuel cells. In this work, an overview on water gas shift reaction performed in Pd-based membrane reactors is shown, paying particular attention to the influence on the performances of some operating variables such as reaction temperature, reaction pressure, H2O/CO molar ratio and sweep gas.

Water-gas shift reaction is an important industrial reaction, used for producing synthesis gas and ammonia as well as pure hydrogen for supplying at PEM fuel cells. In this work, an overview on water gas shift reaction performed in Pd-based membrane reactors is shown, paying particular attention to the influence on the performances of some operating variables such as reaction temperature, reaction pressure, H2O/CO molar ratio and sweep gas.

•An innovative PCM-based cold energy storage system is presented.•A 25 kWh storage device is described and tested.•The tank is fully charged in 2.5 h and discharged in 1.6 h at high power.•The storage unit can be coupled with HVAC systems for peak shaving.