Abstract:
Nowadays, increasing wastewater amount becomes a serious problem in big cities,especially the domestic wastewater which reaches 75 percent of total wastewater. Wastewatermust be treated before it can be safely discharged to rivers or environment.An activated sludgeprocess is one of the popular and high efficiency treatment processes used in domesticwastewater treatment. However, this process is difficult and complicated to be designed andrequired lots of knowledge as well as experiences.Using an expert system may overcome this design problem. The aim of this researchis to develop an expert system which can be used to assist engineers in design of the domesticwastewater treatment process, using activated sludge. The expert system consists of knowledgebase for activated sludge process design and database of surface and submersible aerators (onlywhich are available in Thailand). The system assists users in design of activated sludge processby providing all required knowledge and mathematical formula as well as doing all calculationusing the input information from the user. After calculation, proper configuration and aeratorswill be selected from the database, and all candidates ranking by hardware or energy cost will bedisplayed.Data from some existing treatment processes which designed by human expert wereused to test the reliability of the expert system. The designs from the expert system are closed tothose designed by human expert when typical values of parameters were used. When somedesign parameters (FIM ratio or MLVSS), were carefully selected, the differences betweenexpert system and human were almost negligible.