Homogeneous enriched biosolids product and process of bio-nutrient granulation for making same
US9061948B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Jul 15, 2013 |
| Grant date | Jun 23, 2015 |
| Priority date | — |
| Expiry date | Jul 15, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02A40/20
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A nutrient enriched biosolids fertilizer product including dried granules or pellets of a homogeneous mixture of biosolids and nutrients selected from the group consisting of nitrogen, phosphorus and potassium compounds resulting in a NPK assay of 4 to 15 N-1 to 10 P-4 to 15 K, and a process for producing a fertilizer including the following steps: 1) mixing wet sewage sludge cake with nutrients selected from nitrogen, phosphorus and potassium compounds, in a mixer together with recycled dried granules or pellets of biosolids fertilizer product to form a dryer homogeneous mixture; 2) granulating or pelletizing the dryer homogeneous mixture to result in granules or pellets; 3) drying the granules or pellets of homogeneous mixture to result in dried granules or pellets of the biosolids fertilizer product; and 4) recycling a portion of dried granules or pellets of homogeneous mixture to the mixer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.