Supply Double Superphosphate (DSP) Available P2O5 ranges from 20%-38%
Double Superphosphate
Description: Enriched Superphosphate (ESP) or Double Superphosphate (DSP)
Essential Components: Ca (H2PO4)2·H2O and CaSO4
Quality Standard: Q/YLL01-2008 and Q/YLL02-2008
Property: grey or grey-white loose powder or granule (1~4.75mm or 3.35~5.6mm). Available P2O5 in the product falls in between that of the single superphosphate and the triple superphosphate. The product is of moisture absorption and liable to caking after affected with damp.
Introduction of the product:
1. Although ESP is a new product in our domestic market, it has been applied in America since 1953 and widely used in Southeast Asia and Latin America. After trial application in Henan and Shaanxi since 2005, the product has been highly accepted and praised by general farmers for its excellent cost performance.
The total P2O5 in the product is 20% ~ 38% and the available P2O5 ranges from 18% to 36%. It contains rich medium and trace elements such as sulfur, calcium, silicon, magnesium, manganese and iron, and is a water soluble phosphorous and calcium based fertilizer with rich nutrient. The specifications of the fertilizer commonly applied in foreign countries are 22%, 24% (Latin America), 28%, 36% (Southeast Asia), etc, and those prevail in the domestic market are 28%, 30%, 32%, 36%, etc.
The production process of ESP is relatively complicated and the main procedures are shown as follows: Acid mixing→Mix and combination→Chemical synthesis→Curing→PH regulating→Granulation.
2. Nutrients of the enriched superphosphate consists of not only phosphorous but also sulfur that is deficient in the triple superphosphate. Besides, the ESP also has the following six advantages:
(1) Medium and low grade rock phosphate can be used in a large scale. It overcomes the problem that the medium and low grade rock phosphate can be used to produce only 14% superphosphate, enhances the comprehensive utilization of resources and strengthens the sustainable development of the resources available.
(2) Relieve the labor intensity of farmers. Applying ESP to plants can help to relieve the intensity of work.
(3) Save the capacity of transportation and relieve the pressure of railway. Compared with the single superphosphate, ESP has higher content of phosphorus and thus the transportation price per unit of phosphorous is 1:2 (12% : 24%) or 1:3 (12% : 36%).
(4) The ratio of water soluble P2O5 to available P2O5 is the highest among the like products, which is about 90%.
The single superphosphate: 12/16=75%, the triple superphosphate: 28/44=86%, the enriched superphosphate: 28/32≈90%
(5) The product contains sulfur that provides nutrient good for improvement of soil conditions. The ESP contains about 5% sulfur, however the TSP contains only 0.1% sulfur. As we know, sulfur plays an important role in improving the soil texture and strengthening the growth of plant fiber, so it can improve plants performance of wind and lodging resistance. According to the situation of trial application of ESP in Indonesia and Latin America, the soil texture has been improved obviously than it was before. The ESP is physiological acidic fertilizer that is especially suitable for the alkali soil in the Northwest China and North China.
(6) Its essential component is water soluble monocalcium phosphate that can be easily taken up by plants and is regarded as the best calcium supplement for plants.
3. Method of application of ESP:
(1) The effective application method of ESP is the same as with the single superphosphate, that is to say it can be used as base fertilizer and top dressing. Considering the content of available P2O5 in ESP is more than that in SSP, the application rate of the ESP can be scaled down according to the content of the total P2O5.
(2) The ESP is physiological acidic fertilizer and its essential components are mono-calcium phosphate and calcium sulfate, which has high manurial effect, distinguished adaptability and obvious efficiency for improvement of soil conditions. So the product is especially suitable for the saline-alkali soil in the north of China. The product is good for sprouting of plants, growth of roots and developing of plants and can be used as base fertilizer, seed manure, top dressing and raw material of the compound fertilizer. The ESP can be applied separately or used together with other nutrimental fertilizers, especially with the nitrogenous fertilizer, which is conducive to nitrogen fixation.
(3) After mixed with other fertilizers, the product should be applied to plants immediately, e.g. after ESP is mixed with the , the mixture is liable to moisture absorption after air slaking, if it is put aside for a long time, the nitrogen will loose dramatically and the available P2O5 will convert to insoluble P2O5. ESP is not advisable to be used together with alkaline fertilizer for the reason that it will result in phosphate degradation and reduce the manurial effect.
(4) As for the common seeding plants and field crops, the fertilizer is applied usually on both side of a seed or 4~5cm below a seed or sowed together with seeds after being mixed. While top dressing, the fertilizer should be applied to the place where the root system is mostly developed.
Enriched Superphosphate fertilizer(ESP)
