Clean fertilizers for agriculture?
According to US Department of Agriculture statistics, from July 30, 2008 through June 30, 2009, 17.7 million tons of primary inorganic plant nutrients (nitrogen, phosphorus, potassium — the N-P-K on your bag of fertilizer) were used in the US. For selected secondary, micronutrients, and natural organic materials (gypsum, sulfur, sulfuric acid, zinc, compost, dried manure, sewage sludge, and other organic materials), FY2009 saw 2.3 million tons consumed. For comparison, the total weight (20 million tons) is the equivalent of 220 Washington Monuments.
“Bio-processed mineral fertilisers including micro-elements”, patent number 8,066,793, was issued on November 29, 2011 to Clive Prebble Sinclair (Pukekohe, New Zealand) and assigned to Kagree Holdings Limited (Waiku, New Zealand). The patent is classified as 71/8, which includes inventions using bacterial fermentation or decomposition processes to produce fertilizer. For a historical perspective, the earliest US patent (number 26,184) issued in this class and subclass was for improvement in fertilizers to Louis Harper of Navasink, NJ on November 22, 1859.
Claim 1 states:
A bio-processed mineral fertiliser comprising:
a crushed phosphate-rich mineral substrate, the mineral substrate having been at least partially rendered bioavailable by a composting process utilizing microorganisms;
organic proteinaceous matter;
cellulose-rich particulate material;
and an effective amount of one or more selected microelements, the microelement being chelatedly bound to the organic proteinaceous matter and/or to the mineral substrate component wherein the fertiliser has a neutral pH, and is capable of slowly releasing the bound one or more microelements over an extended period of time after application of the fertiliser to soil, yet not exposing the composting microorganisms or existing soil microorganisms to a toxic concentration of said one or more selected microelements.
The invention describes a method of including micro-elements in a dry, flowable fertilizer of degraded minerals together with micro-organisms by the use of chelated microelements within the nutrients provided to the micro-organisms at the start of a composting procedure. The minerals can include limestone, zeolites, serpentine, or rock phosphate or a combination, ground to a particle size of 0.3-0.7 mm, and used in part as a digestible substrate (which becomes partly decomposed) by the micro-organisms which are nourished with some waste protein material under relatively high temperatures for a period of weeks. The waste protein material used as nutrients usually comprises waste from the fishing industry (about 70% by weight of a catch is not used for human consumption).
Several aspects of this invention are noteworthy and allow it to be located in multiple locations within the patentECO clean technology ecosystem.
- This biomediated fertilizer will result in an increased microbial biomass in the soil, which will enhance crop yields and provide a carbon dioxide sink.
- The total amount of a microelements required for effective treatment is far less (than with conventional crop treatments) when the microelement has been included into the biomass, than if the microelement was spread on the land as an inorganic salt. Further, toxic effects of direct application on soil micro-organisms are absent. Release is slow and is likely to be directly from micro-organism to plant root hairs within or near the rhizosphere, so that waterways are not contaminated.
- The invention is capable of consuming considerable quantities of fish offal (that is, the about 70% of the original catch of a fishing vessel that is not usable as fish fillets).
- Macro- and micronutrients are released to the soil slowly, thus reducing episodic loading to neighboring waterways following rain and snowmelt events.
Increased agricultural use of fertilizers such as this could be an important contributor to reducing nonpoint source nutrient loads to water resources like Chesapeake Bay and the Mississippi River and Gulf of Mexico, and to increasing crop yields in a cost-effective way for farmers.