The present study is aimed to access the growth rates, biomass productivity and nutrient removal in different concentrations of microalgae Botryococcus sp. beads using kitchen wastewater as a media. Verhulst logistic kinetic model was used to measure the optimal concentrations of microalgae Botryococcus sp. in kitchen wastewater in terms of cell growth rate kinetics and biomass productivity. The study verified that the maximum productivity was recorded with 1×106 cell/ml of the initial concentration of Botryococcus sp. with 42.64 mg/l/day and the highest removal of tp and ammonia was obtained (78.14% and 60.53% respectively). The highest specific growth rate of biomass at 0.2896 μmax/d compare to other concentrations, while the lowest occurred at concentrations of 105 cells/ml at 0.0412 μmax/d. The present study shows the different concentrations of Botryococcus sp. in alginate beads culturing in kitchen wastewater influence the cells growth of biomass and nutrient uptake with optimum concentration (106 cells/ml) of Botryococcus sp. which is suggested for wastewater treatment purposes. The result of scanning electron microscopy (sem) shows differences in morphology in terms of surface; smoother and cleaner (before the experiment), cracks and rough surface with black/white spots (after the experiment). These findings seemly can be applied efficiently in kitchen wastewater treatment as well as a production medium for microalgae biomass.

Flexible and rigid road pavement deteriorates over time and needs high-performance patching repair materials. Cold mix asphalt patching is an easy and inexpensive repair material to repair potholes and other damaged roads. However, the repaired road pavement fails because it doesn’t have adequate compressive and bonding strength to the substrate. Thus, this research uses high-performance geopolymer repair materials to patch against road pavement potholes substrate. Geopolymer repair materials could improve the bonding strength, making them suitable for road repair purposes. For making geopolymer repair materials, the main materials used were high calcium aluminosilicate source materials such as fly ash, sodium hydroxide, sodium silicate, and water. This study tested the compressive and bonding strength of geopolymer repair materials after 1, 7, 14, and 28 days. This study found that the compressive strength of 90 g of alkali activator was the highest, at 37.0 MPa. The bonding strength improved gradually from day 1 to day 14, and then considerably on day 28. The compressive strength and bonding strength both increase in direct proportion to the amount of alkali activator present. Alkali activator is optimal at 90 grams for compressive strength and bonding strength of geopolymer repair materials.