Talk:Slow sand filter

Quick correction
Sand filters aren't unique in utilizing microorganisms; pretty much all water filtration processes do. 76.103.182.153 (talk) 04:22, 14 September 2009 (UTC)

Slow sand filters *are* unique in having biological action. Rapid gravity filters *do not* have any significant biological activity. Manganese removal filters *do not* have any significant biological activity. Waste water filters fall into a different category. Denitrifying sand filters do have significant biological activity, and are clean water treatment, but are not really designed for filtration - they are designed to provide a media for the biofilm. Slow sand filters have the double action of filtration and biological activity. Bendel boy (talk) 13:22, 14 September 2009 (UTC)

Merge proposal from Sand filter
A Slow sand filter is a very different technology from most other sand filters. Slow sand filters use biological processes to treat water, rapid gravity and upward flow sand filters using physical properties. I would therefore oppose the merge but would suggest instead a re-working of Sand filter to omit Slow sand filter and concentrate on true sand filters Velela (talk) 13:16, 15 March 2009 (UTC)
 * On second thoughts it might simply be better to make Sand filter into a disambig page since all the text is already included in Rapid sand filter. Velela (talk) 13:56, 15 March 2009 (UTC)

I have made some mods to "sand filter" and leave the useful links to the examples. I will do a little more work when I have the time! (Unsigned comment)

There are several issues here. From a scientific point of view, slow sand filters (according to the description) are not filters operating by filtration, but biological digesters, supporting microbes with sand as a substrate. From a social use point of view, sand filters have nothing to do with international development - they are simply a process technology, and can be used anywhere, depending upon the practical considerations. I would also therefore oppose the merge; the information might be better classed under the umbrella of "Water_treatment" and linked from there. Wikiwayman (talk) 09:57, 13 August 2009 (UTC)

I oppose the merge. Slow sand filters are a subcategory of sand filters and so merging the 'sand filter' entry into this article would be technically incorrect. The heirarchy should be sand filters at the top, followed by subcategories including recirculating sand filters, slow sand filters, etc.66.80.65.244 (talk) 20:15, 18 September 2009 (UTC)

I too (strongly) oppose this merge. Some of the points below have already been made, but this merge is completely off-beat. It really doesn't make any sense to merge these filtration methods, simply because they all use sand somewhere in the filtration process. I my opinion the important arguments against the merge are: KCN nontoxic (talk) 19:14, 26 July 2010 (UTC)
 * 1) Slow sand filters utilize biological processes to remove unwanted nutrients from the water. It is true that some mechanical filtration will occur in the filter bed, but this is actually an unwanted side-effect of the passage of non-potable water through the filter medium. Optimally, there should be several settling ponds before leading any water to the slow sand filter. The exact purpose of the settling ponds is to reduce the mechanical filtration acting in the filter as much as possible, since any mechanical filtration leads to eventual and premature clogging of the sand medium. By far, most of the filtration process takes place in the top layer (schmutzdecke/sludge). The sand below is essentially a backup for the effectiveness of the schmutzdecke and a support medium for the sludge and the overhead water.
 * 2) Slow sand filters do not use flocculation chemicals, whereby the water being led to the filter and the sludge produced from slow sand filters are of a completely different category, with completely different handling options.
 * 3) In relation to developing world issues, the slow sand filtration method has the benefit of being simple, cheap, effective, easy to install, easy to understand, easy to optimize during a running operation. It is important to point out, that an operational slow sand filter demands a lot of surface area (more filters being run at the same time, to allow for scraping and washing of old sandbeds, maintenance of pipe gallery etc.). Moreover, some manual labour is also needed in the maintenance and optimization of an operational slow sand filter (using heavy machinery is possible, but really, in a developing world setting, it would make more sense to use more hands, than more machinery). An optimized slow sand water filtration plant would be designed with gravity flow in mind, to reduce needed pumping power as much as possible. In stark contrast the two mechanical filtration processes demand a somewhat more developed infrastructure in a more dense utilization of surface area at the water filtration plant. Also critical is delivery of chemical agents, sludge disposal, presumable micro-pore cylinder operation etc. All of which is based of ample and reliable power supply to pressure pumps and what-nots.
 * 4) In relation to the Wiki project, it might be wise to look into differences for urban and rural needs. For instance slow sand filters are actually to this day still being used in the water supply for London, U.K., and in a developing world setting, I believe the slow sand filter to be a superior method than any other - especially in rural settings, where cheap land is available for a properly planned water filtration plant along with plenty of experienced manual labour.

External links modified
Hello fellow Wikipedians,

I have just modified 3 external links on Slow sand filter. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Corrected formatting/usage for http://www.who.int/water_sanitation_health/publications/ssf/en/
 * Added archive https://web.archive.org/web/20060316064200/http://www.the-ecentre.net/resources/e_library/doc/11-WATER.PDF to http://www.the-ecentre.net/resources/e_library/doc/11-WATER.pdf
 * Added archive https://web.archive.org/web/20060316064200/http://www.the-ecentre.net/resources/e_library/doc/11-WATER.PDF to http://www.the-ecentre.net/resources/e_library/doc/11-WATER.pdf

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Cheers.— InternetArchiveBot  (Report bug) 03:19, 25 December 2017 (UTC)