Method of converting sewage sludge to fertilizer
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
May 28, 1985
Grant Date -
N/A
app pub date -
Oct 17, 1983
filing date -
Oct 17, 1983
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A method of converting sewage sludge solids into dense controlled release, attrition resistant fertilizer agglomerates is disclosed. The method is carried out by forming a fertilizer premix from dry sewage sludge solids and uncondensed liquid ureaform. Acidic material, preferably phosphoric acid, is distributed throughout the premix to bring the pH to between 4 and 6, and the premix is heated for 5 to 60 minutes to 120.degree. C. The heated premix is compressed between solid surfaces at pressures between 500 and 10,000 pounds per square inch to form agglomerates. The method is preferably carried out on a continuous basis using a heated blender and conveyor for blending and heating the fertilizer premix containing the sewage sludge solids, liquid ureaform, and phosphoric acid. Continuous compacting rollers are used to convert the premix to fertilizer agglomerates which may be readily broken up and screened to any desired fertilizer particle size range. The fertilizer produced releases nitrogen safely and at a slow rate. Complete fertilizers may be produced by the method of this invention, and worthless, very light weight sewage sludge solids may be converted to useful plant food products.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully