← Back to catalogue
Published

slow sand filter

vr.tr.slow-sand-filter · thing-q2608039

Let an agent explain slow sand filters, relay principles, design, performance and maintenance from water engineering and WHO sources, and distinguish slow sand filters from rapid sand filters, biosand household filters, membrane filtration and chlorination, noting that treated water quality must be verified and boil water advisories followed.

Thing Registry Physical world and living systems PHY.BLT

Bundle → Layer → Finding → Questions Filled

4 bundles · 8 layers · 8 findings · 16 questions

Understand What a slow sand filter is.

Definition

Definition.

Definition

Definition.

  1. What is a slow sand filter, and how does it differ from rapid sand filters, biosand filters, membranes and chlorination? definition
  2. Is there a boil water advisory or doubt about water safety, in which case follow local authority advice? boundary

Schmutzdecke

Biological layer.

Schmutzdecke

Schmutzdecke.

  1. What is the schmutzdecke and how does it remove pathogens? definition
  2. Which entry fits biofilm? action
Design Design.

Sizing

Sizing.

Sizing

Sizing.

  1. How are filter area, sand size and flow rate chosen? measurement
  2. Which references are standard? provenance

Maintenance

Maintenance.

Maintenance

Maintenance.

  1. How are filters scraped and resanded? provenance
  2. Which sources are cited? provenance
Performance Performance.

Removal

Pathogen removal.

Removal

Removal.

  1. How effective are slow sand filters, and what extra disinfection is recommended? provenance
  2. Which entry fits water disinfection? action

Standards

Standards.

Standards

Standards.

  1. What do WHO guidelines say about multi-barrier treatment? provenance
  2. Which entry fits WHO Guidelines for Drinking-water Quality? action
Context History and development.

History

History.

History

History.

  1. How did slow sand filtration help control cholera, as in Hamburg and Altona in 1892? provenance
  2. Which entry fits 1892 Hamburg cholera epidemic? action

Development

Small communities.

Development

Development.

  1. Why are slow sand filters suited to low-resource settings? provenance
  2. Which entry fits WASH? action

Classifiers Filled

Family
Thing Registry
Category
Physical world and living systems
Entry kind
thing
Plane
PHY
Domain
PHY.BLT

What it is Filled

A water treatment filter in which raw water flows slowly downward through a bed of fine sand, where a biological layer called the schmutzdecke forms on the surface and removes pathogens and organic matter through biological, physical and chemical processes, first used for public supply by James Simpson for the Chelsea Waterworks Company in London in 1829, still valued for small communities because it needs no chemicals and little energy, though it requires land and periodic scraping.

Why it exists Filled

Let an agent explain slow sand filters, relay principles, design, performance and maintenance from water engineering and WHO sources, and distinguish slow sand filters from rapid sand filters, biosand household filters, membrane filtration and chlorination, noting that treated water quality must be verified and boil water advisories followed.

Distinguishing features Filled

  • Biological layer
  • No chemicals
  • Slow flow
  • Land intensive

What robots and AI may and may not do Filled

Must not

  • Send water to supply from a filter whose biological layer has not matured, without other treatment.
  • Raise flow rates beyond the design so that pathogens pass through.
  • Change settings on a public water treatment plant it is not authorized to operate.
  • Hide test results that show the filter is failing.

Only with a human decision

  • Taking a filter out of service or returning it to supply.
  • Issuing or lifting a boil-water notice.

May

  • Monitor flow, head loss and water quality of a slow sand filter for its operator.
  • Report when a filter needs its surface layer scraped or its sand replaced.

Moral aspects Filled

  • Drinking water safety depends on the filter working; failure can make whole communities ill.
  • Slow sand filters are a low-cost choice for poorer communities, so their reliability matters for equity.

Who is affected

  • People drinking the water
  • Plant operators
  • Communities served

Owners Filled

Steward

The water utility or community that operates the filter, under the drinking water regulator.

Links to other meta-models Filled

parent

  • Q7973769 - registry parent class

related

  • water filter - in general terms
  • schmutzdecke
  • water treatment
  • rapid sand filter

What else AI and robots need to interact with it Filled

Identity and identifiers required Filled

  • Vercy registry: vr.tr.slow-sand-filter
  • Wikidata: Q2608039 (https://www.wikidata.org/wiki/Q2608039)

Direct properties required Filled

  • filtration rate: about 0.1-0.4 m/h
  • first public supply use: 1829 year - Chelsea Waterworks
  • pathogen removal: high for bacteria and protozoa when mature note

Recognition required Filled

  • Biological sand filter for water treatment
  • Slow sand filter, schmutzdecke
  • Rapid sand filters use coagulation and backwashing; biosand filters are household units; membranes use pores; chlorination disinfects chemically
  • Large open or covered basins filled with sand beneath a layer of water.

Capabilities and actions required Filled

  • explain principles
  • relay design and maintenance
  • describe performance
  • distinguish related treatments

Hazards and failure modes required Filled

  • Reduced performance before the biological layer matures
  • Clogging with turbid water
  • Assuming untested water is safe

Standards and interfaces required Filled

  • WHO Guidelines for Drinking-water Quality
  • National drinking water regulations

Context of use required Filled

  • Treating drinking water.
  • municipal slow sand filters
  • community filters
  • riverbank filtration as related
  • household biosand filters

Sources Filled

  1. Wikidata item Q2608039: slow sand filter - identity and sense of the item
  2. Wikipedia: Slow sand filter - general description of the item

Open questions

  • Should the schmutzdecke be a separate entry?
  • How should water engineering sources be linked?
  • How should household biosand filters be linked?

Machine files

Provenance

thing registry research (pass 2) · unreviewed

Built from: models/things/publications/thing-q2608039/spec.json