Pelletized composition for treatment of storm water runoff
US5624576A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 1996 |
| Grant date | Apr 29, 1997 |
| Priority date | — |
| Expiry date | Feb 7, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2978
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A pelletized composition and method of using this composition for removing pollutants from storm water runoff. A bed of the pellets has a useful initial permeability to storm water runoff, and retains a significant proportion of this permeability for a period of several years. Preferably, the pellets are dried to a moisture content of less than 25 wt. % so that they are able to withstand a crush force of at least 7 lb., without structural failure. Optionally, the pellets may contain gravel that forms a core of the compost pellet and that assists in causing the compost to agglomerate into a rounded pellet. When immersed in water, the pellets retain the original dry shape and maintain a significant proportion of the crush strength while providing interstitial spaces through which storm water can flow thereby reducing the problem of sedimentation that is encountered in unpelletized beds of compost used in this service.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.