Numerical and Experimental Study of a Multi-Generation Desalination Power Plant

The demand for more efficient power generation is not only a prominent subject for environmental reasons but for economic reasons as well. Continuing growth in population contributes to more and more consumption of fresh water, demanding less expensive desalination production, especially in the regions with little or no natural fresh water. Multigeneration desalination power plants may provide solutions to these issues through advanced and efficient designs that are capable of supplying fresh water and power to remote or arid regions of the world. This paper examines the flexibility and versatility of multigeneration systems to showcase the myriad of combinations that are available to accommodate any specific application. It also proposes a specific design for a multi-stage flash desalination system that is powered directly by the exhaust gases of a natural gas micro-turbine capable of producing around 1 MW of electrical power. The performance characteristics, the fresh water produced per kW and the overall plant efficiency, are numerically investigated and compared with previous designs that were analyzed on a larger scale. It is determined that the multigeneration system can produce 56,891 gallons of fresh water per day and an estimated 4.07 tons of salt per day and that a small scale multi-generation desalting systems is feasible.

Reproductive Toxicities of Tetradecyltrimethylammonium Chloride and Tetradecyltrimethylammonium Bromide on Caenorhabditis elegans over Four Consecutive Generations

Quaternary ammonium compounds (QACs) become emerging pollutants and their toxicities earn increasing attention.So far,their reproductive toxicities were poorly investigated,and their effects over generations were even less explored.In the present study,reproductive toxicities of two QACs,i.e.,tetradecyltrimethylammonium chloride (TTAC);tetradecyltrimethylammonium bromide (TTAB) were studied on Caenorhabditis elegans with a consecutive exposure over four generations (from F1 to F4).The effects of TTAC on total and initial reproduction showed stimulation and inhibition,which oscillated from F1 to F4.The effects of TTAB on the total reproduction commonly showed stimulation over generations with the greatest stimulation in F2,and it inhibited the initial reproduction but stimulated the reproduction duration.Further exploration demonstrated that TTAC and TTAB significantly disturbed the levels of spermatocyte protein 8 (SPE8);sperm transmembrane protein 9 (SPE9);vitellogenin (Vg);major sperm protein (MSP);ephrin receptor protein tyrosine kinase (VAB-1);the expressions of vab-1,ceh-18,set-2,met-2 and mes-4.Such disturbances demonstrated that both QACs impacted the reproductive processes via oocyte meiosis,gonadal support and germline development.Notably,the effects of TTAC and TTAB in parents were connected with those in the offspring,which highlighted the roles of reproduction in connecting generations.In addition,different effects between TTAC and TTAB demonstrated the anionic influences on the QACs’ toxicities.