In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that use...In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that uses solar radiation to warm-up the air;for instance, within saunas. Authors coined the term sustainable technological innovation to refer to a technological innovation in accordance to the principles of sustainability. The object of this research was comparing the sustainability of a Fresnel Lens Solar Concentration (FLSC) against the sustainability of other twelve alternatives to generate heat. This article assesses the sustainability of fourteen technological options for heat generation and transfer to saunas in the northwest region of Mexico where temperatures often reach above 45 C and where there is a greater potential for exploiting solar energy. Emergy accounting, economic analysis, and global warming potential are the three indicators considered in quantifying sustainability. Results show that infrared ceramic photovoltaic, infrared carbon photovoltaic and infrared metal photovoltaic are the most sustainable systems. The Fresnel device reached the fourth and tenth position, using electricity from photovoltaic and from grid respectively, among all fourteen assessed devices, respectively. Although Fresnel equipment does not release any global warming gases into the atmosphere, or even it demands low amount of non-renewable resources, 1.40 and 4.47 E17 seJF/yr. it requires high economic investment, 20,800 and 79,600 USD/yr, for the implementation and operation phases, which decrease its sustainability performance compared to twelve other evaluated devices.展开更多
The paper was monitored the conductivity (g.L"l of NaCI), the absorbances values (Abs) and the amount of TOC (total organic carbon), before and after five consecutive dyeings made with reuse water, obtained fro...The paper was monitored the conductivity (g.L"l of NaCI), the absorbances values (Abs) and the amount of TOC (total organic carbon), before and after five consecutive dyeings made with reuse water, obtained from treated effluent by UV/H202 photocatalysis. All rates of decolorization were above 92%, the removal of total organic carbon was above 89% in all treatments and the economy of NaCI was from 3.10 in the first recipe, 3.17 in the second, 3.49 in the third, 3.79 in the fourth and 4.05 in the fifth recipe. The five dyeings compared with same dyeings made with deionized water presented a color deviation (AE*) below 1. The conventional dyeings would consume 80 L/kg against 40 L/kg used in the dyeing process proposed in this study, representing a great economy of water, with no discharge of effluents.展开更多
The aim of this paper was to study three variables in hydrogen peroxide bleaching of cotton fabrics: the amount of hydrogen peroxide (H2O2), peroxide stabilizer (Na2SiO3) and the process temperature. The factoria...The aim of this paper was to study three variables in hydrogen peroxide bleaching of cotton fabrics: the amount of hydrogen peroxide (H2O2), peroxide stabilizer (Na2SiO3) and the process temperature. The factorial planning of two levels and three factors was done in order to obtain an optimized recipe for subsequent comparison with commons recipes used in industry. Were evaluated the brightness (DL), energy consumption (dQ), H2O2 residual (Rox), processing time and ecological costs.展开更多
文摘In the search for renewable energy sources, solar energy appears, among others, as a powerful alternative;mainly for those countries located at Earth’s equatorial region. This is the case of a Fresnel device that uses solar radiation to warm-up the air;for instance, within saunas. Authors coined the term sustainable technological innovation to refer to a technological innovation in accordance to the principles of sustainability. The object of this research was comparing the sustainability of a Fresnel Lens Solar Concentration (FLSC) against the sustainability of other twelve alternatives to generate heat. This article assesses the sustainability of fourteen technological options for heat generation and transfer to saunas in the northwest region of Mexico where temperatures often reach above 45 C and where there is a greater potential for exploiting solar energy. Emergy accounting, economic analysis, and global warming potential are the three indicators considered in quantifying sustainability. Results show that infrared ceramic photovoltaic, infrared carbon photovoltaic and infrared metal photovoltaic are the most sustainable systems. The Fresnel device reached the fourth and tenth position, using electricity from photovoltaic and from grid respectively, among all fourteen assessed devices, respectively. Although Fresnel equipment does not release any global warming gases into the atmosphere, or even it demands low amount of non-renewable resources, 1.40 and 4.47 E17 seJF/yr. it requires high economic investment, 20,800 and 79,600 USD/yr, for the implementation and operation phases, which decrease its sustainability performance compared to twelve other evaluated devices.
文摘The paper was monitored the conductivity (g.L"l of NaCI), the absorbances values (Abs) and the amount of TOC (total organic carbon), before and after five consecutive dyeings made with reuse water, obtained from treated effluent by UV/H202 photocatalysis. All rates of decolorization were above 92%, the removal of total organic carbon was above 89% in all treatments and the economy of NaCI was from 3.10 in the first recipe, 3.17 in the second, 3.49 in the third, 3.79 in the fourth and 4.05 in the fifth recipe. The five dyeings compared with same dyeings made with deionized water presented a color deviation (AE*) below 1. The conventional dyeings would consume 80 L/kg against 40 L/kg used in the dyeing process proposed in this study, representing a great economy of water, with no discharge of effluents.
文摘The aim of this paper was to study three variables in hydrogen peroxide bleaching of cotton fabrics: the amount of hydrogen peroxide (H2O2), peroxide stabilizer (Na2SiO3) and the process temperature. The factorial planning of two levels and three factors was done in order to obtain an optimized recipe for subsequent comparison with commons recipes used in industry. Were evaluated the brightness (DL), energy consumption (dQ), H2O2 residual (Rox), processing time and ecological costs.