1. Justifications of the proposed schemes -the structural problem& the chemical injection locations
2. Design impeller and tank type affecting energy efficiency, cost, flocculation size. Design Diffuser Walls and Baffles used for Minimizing Short Circuiting
3. Design launder type, structure, sludge and scum model
Filtration의 세번째 key concept 이유: (to promote readily biodegradabl
Ⅲ Flocculation
The purpose of flocculation is to uniformly mix coagulated water to produce either settleable or filterable floc and accelerate the rate of particle collisions, causing the agglomeration of electrolytically destabilized colloidal particles into settleable and filterable sizes.
Considerations of flocculation are:
1. Baffling to prevent of flow short-circuiting
2. Tapered
History and Development of the Activated Sludge Process
- The activated sludge process presently represents the most widespread technology for wastewater purification.
- The invention of the activated sludge process is connected with the efforts of British and American engineers at the end of the last century to intensify biological purification in fixed-film systems.
: wastewa
sludge)라고 하고, 활성오니의 형성과정을 플록형성(flocculation), 이 원리를 이용한 하수의 처리방법을 활성오니법(activated sludge process)이라 한다.
*장점 및 단점 - 활성오니법은 가장 효율이 높은 방법이지만 경비가 가장 많이 들고, 유기물 부하 등의 갑작스런 변동에 대한 적응력이 약해 벌킹(bulking) 등
Process Selection Considerations
Selection of an activated-sludge process for BOD removal and nitrification is a function of many considerations including specific site constraints, compatibility with the existing process, compatibility with existing equipment, present and future treatment needs, level of capability of the operating staff, capital costs, and operating cost.
Complete-mix activ