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The urge of environmental friendly techniques in textile processing is gaining much attention due to high risks of effluent load causing eco-imbalance. For the present study, the cotton fabric and Reactive Violet H3R dye solution were treated with microwave radiation for 2, 4, 6, 8 & 10 min. at different powers (low, medium & high). Dyeing was performed using un-irradiated (NRC) and irradiated cotton (RC) with un-irradiated (NRS) and irradiated dye solution (RS). Different dyeing parameters were optimized and ISO standard methods for color fastness were employed to rate the color change before and after irradiation. It is found that microwave irradiation for 8 min. at high power has given good colour strength. When 60 mL irradiated dye solution of 7.5pH containing 8g/L of salt as exhausting agent is used to dye irradiated fabric at 60^oC for 55 min. ISO standards for colorfastness employed at various shades have shown that microwave irradiation has improved the rating of fastness properties. It is concluded that microwave irradiation has a promising potential to improve the color strength and dyeing properties under mild conditions.

The Membrane Bio-Reactor (MBR) technology offers a series of environmentally-friendly advantages, such as high quality effluent, pathogens removal capacity and avoided use of chemicals for disinfection, allowing it to be regarded as an environmentally friendly technology, when applied for wastewater treatment. However, membrane fouling still remains a major drawback, preventing its widespread application for municipal or industrial wastewater treatment. The use of additives (i.e. adsorbents, bio-carriers etc.) is considered to be among the major strategies implemented for membrane fouling control over the last few years. The present work examines the influence of bio-carriers addition, as well as of zeolite powder on the reversible and irreversible membrane fouling of a lab-scale MBR. High-strength synthetic municipal wastewater (with BOD5 around 1000 mg/L) was fed as the substrate for the activated sludge process and a flat-sheet microfiltration membrane was operated for solids (biomass) - liquid separation at the flux of 17 L/m2h. The obtained results showed that the addition of zeolite contributed mainly to the alleviation of irreversible fouling, leaving the reversible fouling practically unaffected, while the addition of bio-carriers had quite the opposite effect. In addition, it was shown that the lab-scale MBR system operated successfully, treating a high-strength synthetic municipal wastewater, as high removals were observed in terms of both organics and especially of ammonium removal (over 98%).

This study investigates the effectiveness of fly ash-based geopolymer concrete was conducted to be used as an alternative material to replace the normal concrete. The concrete mixture was prepared by mixing fly ash, fine aggregate, nano-slag, and SP in Na2SiO3/NaOH solution. The mixture was divided into three different groups, with constant water to fly ash ratio of 0.1, and different alkaline content: 0.4, 0.45, and 0.5 of fly ash rather than two curing techniques (moist and autoclave). Several hardeness properties of concrete like compressive strength, density; and splitting tensile strength were examined after 28 d. The microstructural development of geopolymer concrete was monitored using X-Ray Diffractometer. Based on the results of this investigation, it is recommended to cure the geopolymer concrete by autoclaving rather than the traditional moist technique, especially at lower alkaline dosage. However, the partial addition of nano slag by weight of FA had a positive effect on both curing techniques.

New challenges for industrial microbiology and biotechnology of algae are to increase the efficiency of microalgae growth rates and decrease the cultivation costs. Algae could be cultivated in fresh water as well as in salty sea water or wastewater. Microalgae biomass can be used as a sorbent to remove microcontaminants (e.g. heavy metals, biogens) from wastewater. The obtained results showed that there is a possibility of application of a cheap and universal growing medium (Bf) despite common fertilizers: Bristol or BG-11 to cultivate Chlorella vulgaris and Scenedesmus armatus. The mixotrophic condition can be useful for cultivation of Chlorella vulgaris and Scenedesmus armatus. The highest concentrations of algal biomass for both species were determined after the application of the Bf medium, lower after the BG-11 medium and the lowest after the Br medium in autotrophic as well as mixotrophic conditions. The number of C. vulgaris cells in mixotrophic conditions was higher than S. armatus. The utilization of cheap growing media will lowering the production costs of algal biomass on a large scale.