Technology Selection Reflections. Getting rid of all the muck Biggest bang for the buck Reliability, no need for luck. Selecting a Treatment Process. Input. Algorithm. Output. Water characteristics. Treatment Process. Resources (Capacities). Decision. Institutional. Economic.
Getting rid of all the muck
Biggest bang for the buck
Reliability, no need for luck
More data, but no design change!
Amount of Data
How could you increase the y intercept? ____________
Identify critical data!
How could you increase the slope? _________________
We will return to this question after we review our options
Get turbidity below
30 NTU (WHO limit for disinfection only treatments)
5 NTU (Particle removal technologies should exceed this goal)
Hazardous chemical removal
Anthropogenic contaminationWater Treatment Objectives
WHO is working on guidance for these contaminants
Need a good small-scale design!
Need a simple cleaning technique!
Flow control (“floating weir”)
Can’t handle much head loss
Scour when head loss is low
Requires a hill side
Top layer of sand can dewater if supply water stops or if head loss is low
3 200 L drums
Takes up lots of space
*Okay, he designs and sells slow sand filters…
Will determine treatment technology
Assume pathogens are present!
Could each community in the Global South have a designated person who maintains the POU devices?
Add 2 mL of m-endo broth (selective media)
Place membrane filter in the petri dish on top of the nutrient pad
Petri dish with sterile absorbent nutrient pad
8 coliform/100 mL