Theories regarding the growing scarcity of rock phosphates for mineral fertilisers

Transcription

1 Theories regarding the growing scarcity of rock phosphates for mineral fertilisers 1. Rock phosphates are becoming scarce 2. Low-cadmium rock phosphates are becoming scarce 3. Secondary phosphates are needed to replace (scarce) rock phosphates used for mineral fertilisers 4. It is possible to substitute all rock phosphates used for mineral fertilizers with secondary phosphates 5. Admixture ratio is helpful to solve the resource problem posited Brüssel, Folie: 1 Zur Knappheit von Phosphaten

2 P stocks Phosphorus concentration in the earth s crust: 0.09% Natural stocks are divided into 3 categories: Category 1: such P reserves comprise the deposits that are currently able to be mined economically; not all deposits are already being mined. Category 2: P resources comprise deposits that are currently unable to be mined economically. Category 3: the remaining geological potential that is presumed to exist but which has not yet been determined finally. Boundaries are fluid in both directions.

3 Calculation of lifetime Re. theory 1: Category 1 reserves discussed hitherto Annual mining 190 million tonnes (2011). As of 2009, documented P reserves of 15,000-20,000 million tonnes. Static lifetime of reserves derived from this = a maximum of 105 years. In 2009, Morocco then announced an additional 50,000 million tonnes from new reserves Documented P reserves of 71,000 million tonnes (from 2009 onwards) Static lifetime of stocks derived from this (new value) = a maximum of 374 years

4 Other restrictions on availability Dependency on political factors Approximately 80 % of the global P exports come from North Africa (from only two States) and from the Middle East Legislation Increasing need for low-cadmium phosphates due to increasingly stringent fertilisation legislation, feed legislation and food legislation.

5 Consumption of P: Losses of P along the chain of use Mining of rock phosphates (100%) Losses in the processing and spreading of the fertilisers (75 %) Harvested material (40%) Man (20%)

6 Use of P for different purposes in GER (in P!) P sources mineral fertiliser animal feed food cleaning products flame retardants drinking water supply other (PSM, Pharma usw.) Applied as mineral fertilizer manure, sewage sludge, meat and bone meal sewage sludge, meat and bone meal, compost sewage sludge ammon-phosphate? sewage sludge Quantity t/year 102,530 37,490 10,030 10, , ? total Brüssel, Zur Knappheit von Phosphaten Folie: 6

7 Processing rock phosphates into mineral fertilisers hard ground soft ground completely solubilised partially solubilised with acids heat treatment with acids grinding sulphuric acid phosphoric acid super phosphate water-sol triple superphosphate Thomas phosphate e.g. Nova phosphate e. g. hyper phosphate water-sol sol. in citric acid water-sol sol. in formic acid very fast very fast slow fast and slow very slow Brüssel, Zur Knappheit von Phosphaten Folie: 7

8 No Type designation Data on method of production and essential ingredients Minimum content of nutrients (percentage by weight) Data on the expression of nutrients Other requirements Other data on the type designation Nutrient content to be declared Forms and solubilities of the nutrients Other criteria 2 (a) Single superphosphate 7 Soft ground rock phosphate Berlin, Product obtained by reaction of ground mineral phosphate with sulphuric acid and containing monocalcium phosphate as an essential ingredient as well as calcium sulphate Product obtained by grinding soft mineral phosphates and containing tricalcium phosphate and calcium carbonate as essential ingredients 16 % P2O5 Phosphorus expressed as P2O5 soluble in neutral ammonium citrate, at least 93 % of the declared content of P2O5 being water-soluble Test sample: 1 g 25 % P2O5 Phosphorus expressed as P2O5 soluble in mineral acids, at least 55 % of the declared content of P2O5 being soluble in 2 % formic acid Particle size: at least 90 % able to pass through a sieve with a mesh of 0,063 mm at least 99 % able to pass through a sieve with a mesh of 0,125 mm Düngerrecht und Klärschlammaschen Phosphorus pentoxide soluble in neutral ammonium citrate Water-soluble phosphorus pentoxide Total phosphorus pentoxide (soluble in mineral acids) Phosphorus pentoxide soluble in 2 % formic acid Percentage by weight of material able to pass through a sieve with a mesh of 0,063 mm Folie: 8

9 Raw materials, substance group or origin Restriction of the permissible raw materials Supplemental specifications and notes : Phosphate fertiliser from [designation as per column 1] as per Annex 1, No Carbonisation of animal bones Substances as per table 7.2. row Incineration of substances of Ash from substances as per table 7.2 animal origin Incineration of sewage sludge Ash from sewage sludge as per table 7.4 row Phosphate precipitation Precipitation of mineral phosphates with calcium chloride, lime water, magnesium chloride, In granulated or dust-attached form Sieve throughput at 0.1 mm max. 0.2 %, at 0.05 mm max %, at 0.01 mm max %, In granulated or dust-attached form Sieve throughput at 0.1 mm max. 0.2 %, at 0.05 mm max %, at 0.01 mm max %, magnesium oxide or hydroxide Melt gasification Substances as per table 7 Processing temperature 1450 C No addition of substances as per table 8.3. Berlin, Zur Knappheit von Phosphaten Folie: 9

10 Type designation Phosphate fertiliser from [designation as per Annex 2, table 6.2] Type determining components; Nutrient forms and nutrient solubilities Information on nutrient assessment; other requirements Basic composition; Type of production Special provisions, notes % P 2 O 5 Total phosphate, Phosphate assessed as total phosphate, phosphate soluble in 2% citric acid Phosphate assessed as phosphate soluble in 2% citric acid Sieve throughput: 98% at 0.63 mm, 90% at 0.16 mm Tolerances: Total phosphate: 0.8 %- point Phosphate soluble in citric acid: 2 %-points The tolerance set for phosphate must not be exceeded altogether Minimum concentrations Phosphatecontaining raw materials as per Annex 2 table 6.2; from only one substance as per Annex 2 table 6.2 In the type designation the text within brackets is to be replaced by the designation as per Annex 2 table 6.2 column 1. The production method as per Annex 2 table 6.2 column 2 must be specified. Berlin, Folie: 10

11 Permissible phosphate forms and phosphate solubilities Phosphate (P 2 O 5 ) 4.1 Phosphate forms 4.2 Phosphate solubilities Water-soluble P 2 O Neutral ammonia citrate soluble P 2 O Neutral ammonia citrate soluble and water-soluble P 2 O Exclusively mineral acid soluble P 2 O Alkaline ammonium citrate soluble P 2 O 5 (Petermann) P 2 O 5 soluble in 2% citric acid Total phosphate, thereof at least 75% of the specified concentration of P 2 O 5 soluble in alkaline ammonia citrate (Joulie) Total phosphate, thereof at least 55% of the specified concentration of P 2 O 5 soluble in 2% formic acid Total phosphate, thereof at least 45% of the specified concentration of P 2 O 5 soluble in 2% formic acid, at least 20% of the specified concentration of P 2 O 5 water-soluble P 2 O P 2 O 5 soluble in 2% citric acid and in alkaline ammonia citrate (Petermann) Total phosphate (method: mineral acid soluble P 2 O 5 ) Berlin, Folie: 11

12 P requirements of crops (hectare and year) twice-cut meadow 40 kg P2O5 4-5 cuts (intensive use) kg P2O5 Exemplary crop rotation in arable farming winter wheat (80 qt grain) 64 kg P205 winter barley (70 qt grain and straw) 71 kg P2O5 grain maize (100 qt grain) 80 kg P2O5 crop rotation total 215 kg P2O5 Crop rotation average 72 kg P2O5 Brüssel, Folie: 12 Zur Knappheit von Phosphaten

13 Supply of phosphorus for fertilisation from different source substances Long-term removal hectare/year (kg P2O5) kg P2O5 Typical arable farming (average) 72 kg P2O5 Long-term supply of P2O5 hectare/year from mineral fertilisers from manure Total from sewage sludge, meat-and-bone meal and bio-waste 15 kg P2O5 35 kg P2O5 50 kg P2O5 12 kg P2O5 Secondary phosphates have no potential to replace mineral fertilisers, but are important in order to supplement the P supply from mineral fertilisers. Berlin, Folie: 13 Zur Knappheit von Phosphaten

14 160,0 140,0 Substitution potential of sewage sludge as P 2 O 5 fertiliser (1) N P2O5 K2O 120,0 100,0 80,0 60,0 40,0 P-requirement + manure 20,0 Sewage sludge 0,0 Animal byprodukts

15 160,0 140,0 Substitution potential of sewage sludge as P 2 O 5 fertiliser (1) N P2O5 K2O 120,0 100,0 80,0 60,0 40,0 P-requirement + manure 20,0 Sewage sludge 0,0 Animal byprodukts

16 Conclusion (1): Conserving resources of P is more than replacing mineral-fertiliser P During manufacture 1. Include suitable alternative source substances at all stages, Examine the ban on the use of ash from CAT I material Ash from sewage sludge. 2. Favour in this respect methods with high recovery rates. 3. Processing into P fertilisers with a high level of availability (increase in fertilisation efficiency), e.g. dispensing with metal salts in the pricipitation of P. 4. Promotion of high-concentration P fertiliser, this then also reduces the pollutant load used to achieve a fertilisation aim. Berlin, Folie: 16 Düngerecht und Klärschlammaschen

17 Conclusion (2): Resource preservation for P is more than the replacement of mineral-fertiliser P During application: 1. Levelling-out of regional oversupply and undersupply 2. Adjustment of fertilisation recommendations (P concentration categories) 3. Correct types of P fertiliser on areas of land with different ph levels 4. Correction of requirements in the field of organic farming (fertilisation only with rock phosphates) 5. Standard, comprehensible labelling of the solubility of the P fertilisers, which only then will enable the farmer to select the right P fertiliser 6. Fertilisation based on soil-testing results for the respective land also for P this then leads away from multi-component fertiliser mixtures with minimum content of nutrients 7. Agronomic possibilities for increasing the efficiency of P fertilisation Close-to-root application, supplementary N fertilisation) Correct time: in the case of winter wheat, 70% of the P absorption in 4-8 weeks (March to May) Berlin, Folie: 17 Zur Knappheit von Phosphaten

18 General conclusion Use of secondary phosphates as a starting material for fertilisers makes sense if a sufficient level of effectiveness is attained and when used, concentrations / loads of harmful substances comparable to the primary phosphate fertilisers are not exceeded. Thankyou! Berlin, Folie: 18 Düngerecht und Klärschlammaschen