optimization

High concentrations of ammonia in drinking water resources can cause complications and diseases in human, as well as environmental problems such as eutrophication. The aim of this study was to investigate the removal of ammonia nitrogen from wastewater using the nitrification and modeling by response surface method (RSM).

Experiments were performed in a batch mood and in a laboratory scale by evaluating the amount of ammonium in effluent. The ammonium removal efficiency was optimized according to RSM and the central composite design (CCD).

The results of this study showed that by increasing the contact time and decreasing the ammonium load, the efficiency of the system was increased. The best conditions for nitrification were determined as follows; 38 hours of hydraulic retention time and 173.6 mg/L of inlet ammonium concentrations. Under this condition a maximum efficiency of about 70% was obtained.

Due to the high correlation coefficients, the ammonium removal model was significant and the surface response method was a suitable method for optimizing and modeling.

Mechanizing and optimizing the solid waste collection and transportation systems can be af-fected on the environmental effects and handling costs. To reduce the adverse effects and to optimize the solid waste management, it is necessary the existing system such as Noorabad solid waste collection systems be evaluated and better condition be suggested.
This study was conducted in the North West of Lorestan province, Noorabad. Some part of data was obtained from field studies. Real-time data was collected from existing routes in the city using a stop-watch. By mathematical and software (Excell), collected data were analyzed. Then, according to the local information such as population density, waste generation capita, routes and also the application of mathe-matical relationships, the optimum routing vehicle was designed.
Referring to results, the optimize way was selected and the results showed the vehicle costs and shift workers have been reduced about 25 and 50%, respectively. The result of present study is suggested that the 78 storage tanks with a volume about 550 and 660 liter for residential and commercial areas.
Based on the results of present work, it can be asserted that where are the optimum rout of collection system regarding to reduce the handling costs and time and higher level of servicing.