Abstract:
The main objective of this study is to develop a visual basic language program to be used for primary analysis, design and preliminary cost estimation and comparison of biological wastewater treatment systems. This program includes main menu, flow and mass balance, design, plant lay out, hydraulic consideration, cost estimation, cost comparison and analysis parts. The design function of this program includes sand trap or grit chamber, equalization tank, primary sedimentation tank, aeration tank, secondary clarifier, aerated lagoon, anaerobic pond, facultative pond, maturation pond, trickling filter, rotating biological contactor (RBC), anaerobic filter, anaerobic contact process, anaerobic expanded bed, single-stage nitrification, separate-stage nitrification, separate-stage tricking filter, single-stage trickling filter, RBC with combined nitrification, RBC with separate nitrification, nitrogen removal, phosphorus removal, nutrient removal, disinfection (chlorination, ozonation and UV radiation), gravity thickener, dissolved-air flotation (DAF), aerobic digestion, anaerobic digestion, sludge drying beds, filter press and belt filter press. This program will enable engineers in designing more proper and precise wastewater treatment plants in a shorter time. All parameters in this program can be easily changed or corrected in order to give the most satisfying results. Using computer in design and primary cost estimation of wastewater treatment systems can be very useful, because of its time saving and mistake-free calculation. By letting user explore different treatment approaches, one can analyze and finally get the most economical process.