Difference between revisions of "Pretreatment"

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</ul>
</ul>
===Concentrated underground flow===
===Concentrated underground flow===
<h4>Oil and grit seperators (OGS)</h4>
This type of pretreatement is dominated by proprietary systems, some of which have undergone verification under the [http://etvcanada.ca/| Environmental Technology Verification (ETV)] program.
<p>OGS are devices which use physical principles to improve water quality. Typically these are underground chambers installed in catch basins or manholes. Many commercial and custom configurations exist for both new installations and retrofit scenarios. </p>
<table class = "table table-striped table-responsive">
<p>One method is to incorporate baffles within a tank or chamber:
<caption><strong>Inline pretreatment options</strong></caption>
<ul>
<tr class ='success'>
<li>The first baffle slows the incoming water flow, encouraging any larger, heavier particles to drop out of the water, </li>
  <th>Type</th>
<li>A second baffle skims the surface of the water, preventing floating debris, oils and grease from passing. </li>
  <th>Description</th>
</ul>
  <th>ETV products</th>
Proprietary examples of baffle systems (not verified): [http://upstreamtechnologies.us/products/safl.shtml| SAFL baffle]
  <th>Other products (not verified)</th></tr>
</p>
<tr>
<p>Another option is a hydrodynamic device, which forces the incoming water flow into a circular vortex:
<td>OGS Baffles</td>
<ul>
<td>Baffles slow flow, encouraging larger, heavier particles to drop out of the water column. A skimmer may also trap floating debris, oils and grease. </td>
<li>The vortex motion forces the larger, heavier particles are outwards and downwards into a lower chamber, </li>
<td>-</td>
<li>Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber. </li>
<td>[http://upstreamtechnologies.us/products/safl.shtml| SAFL baffle]</td></tr>
</ul>
<tr>
Proprietary examples of <strong>[http://etvcanada.ca/| verified]</strong> hydrodynamic systems : 
<td>Hydrodynamic OGS</td>
<ul>
<td>The shape causes rapidly flowing water to form a vortex which forces the larger, heavier particles are outwards and downwards into a lower chamber. Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber</td>
<li>[http://www.conteches.com/Products/Stormwater-Management/Treatment/CDS.aspx| CDS]</li>
<td>
<li>[https://www.hydro-int.com/en/products/downstream-defender| Downstream defender]</li>
[http://www.conteches.com/Products/Stormwater-Management/Treatment/CDS.aspx| CDS]<br>
<li>[http://nextstorm.ca/sdd/| SDD]</li>
[https://www.hydro-int.com/en/products/downstream-defender| Downstream defender]<br>
</ul>
[http://nextstorm.ca/sdd/| SDD]
Proprietary examples of other hydrodynamic systems (not verified): [http://www.imbriumsystems.com/stormwater-treatment-solutions/stormceptor-systems| Stormceptor]
</td>
<h4>Inline filters</h4>
<td> [http://www.imbriumsystems.com/stormwater-treatment-solutions/stormceptor-systems| Stormceptor]</td></tr>
<p>Using technology adopted from water treatment plants. </p>
<tr><td>Cartridge filters</td>
<ul>
<td>Uses membrane technology adopted from water treatment plants. </td>
<li>[http://www.imbriumsystems.com/stormwater-treatment-solutions/jellyfish-filter| Jellyfish]</li>
<td>-</td>
</ul>
<td>[http://www.imbriumsystems.com/stormwater-treatment-solutions/jellyfish-filter| Jellyfish]</td></tr>
<h4>Catchbasin inserts</h4>
<tr><td>Catchbasin inserts</td>
<p>Great for retrofitting situations, to improve water quality:</p>
<td>Great for retrofitting situations, to improve water quality</td>
Proprietary examples of <strong>[http://etvcanada.ca/| verified]</strong> inserts:
<td>[http://www.cbshield.com/| CB Shield]</td>
<ul>
<td> [http://upstreamtechnologies.us/products/snout.shtml| Snout]</td></tr>
<li>[http://www.cbshield.com/| CB Shield]</li>
</table>
</ul>
Proprietary examples of other inserts (not verified):
<ul>
<li>[http://upstreamtechnologies.us/products/snout.shtml| Snout]</li>
</ul>


===Resources===
===Resources===

Revision as of 14:10, 3 August 2017

Overland sheet flow[edit]

The following pretreatements are recommended where sheet flow is being directed to a BMP (typically a bioretention cell) from the edge of an impermeable surface such as an asphalt parking lot or a paved plaza:

A gravel diaphragm typically requires less setback between the catchment and the BMP. Where space permits, these two designs can be used in combination to even greater effect!

Concentrated overland flow[edit]

Where a curb cut, a disconnected downspout or a swale directs surface water to a point, increasing the flow rate, one or more of the following pretreatments should be considered:

Concentrated underground flow[edit]

This type of pretreatement is dominated by proprietary systems, some of which have undergone verification under the Environmental Technology Verification (ETV) program.

Inline pretreatment options
Type Description ETV products Other products (not verified)
OGS Baffles Baffles slow flow, encouraging larger, heavier particles to drop out of the water column. A skimmer may also trap floating debris, oils and grease. - SAFL baffle
Hydrodynamic OGS The shape causes rapidly flowing water to form a vortex which forces the larger, heavier particles are outwards and downwards into a lower chamber. Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber

CDS
Downstream defender
SDD

Stormceptor
Cartridge filters Uses membrane technology adopted from water treatment plants. - Jellyfish
Catchbasin inserts Great for retrofitting situations, to improve water quality CB Shield Snout

Resources[edit]

This article is particularly heavy on proprietary systems and information. Please inform us of any omissions or broken links using the button below:

  1. REDIRECT Special:ArticleFeedbackv5