Slow sand filtration water treatment plants
Practical Action
Programme of practical courses
TITLE
OBJECTIVE
MATERIAL
METHOD
TIME
INTRODUCTION
DEVELOPMENT
PRACTICAL WORK
REVISION
Start-up of the filter
The participants will be capable of starting up the filter
Slow filter with a clean and properly levelled sand bed
Field demonstration
An hour and a half
Explain the importance of starting up the filter correctly in order
to ensure its effectiveness and produce safe water; point out that
the operators must be capable of starting up the filter. Explain
the steps to be followed in general terms.
Demonstrate the steps to be followed, placing emphasis on the
most important:
1) Explain how to prepare the sand for sifting and how to
clean it
2) Discuss the best way of washing the filter box and how to
put the layers of gravel and sand in place
3) Demonstrate each of the key actions involved in filling
the filter through the bottom, explaining the direction of
the flow in each case and what is being done and why.
4) Allow the participants to ask questions
1) Ask the participants to start up the filter, explaining what
they are going to do before each step. Correct any
mistakes immediately.
2) Ask them to start up the filter under the supervision of
the trainer
3) Ask them to start up the filter again whilst the trainer
makes a note of their performance and their possible
weak points.
Revise the parts that the participants were unsure of.
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