Triple Super Phosphate (TSP) is a high-analysis phosphatic fertilizer produced by treating phosphate rock with phosphoric acid. It contains a very high concentration of water-soluble phosphorus and supplies phosphorus in a readily available form that supports root development, flowering, and overall crop productivity.
Product Identification
| Parameter | Specification |
|---|---|
| Chemical Formula | Ca(H₂PO₄)₂·H₂O |
| Fertilizer Grade | 0-46-0 (N-P₂O₅-K₂O) |
| Category | Fully water-soluble phosphatic fertilizer (P only) |
| Nitrogen Content | Nil |
| Calcium Content | Present (secondary nutrient) |
| Granule Reaction | Acidic |
Chemical Nature
TSP is a chemically processed calcium phosphate fertilizer formed by acidulating phosphate rock with phosphoric acid. It provides highly reactive, water-soluble phosphorus without adding nitrogen.
Strengthening & Granulation Behavior
TSP granules develop mechanical strength through:
✔ Crystallization of monocalcium phosphate
✔ Controlled granulation moisture
✔ Thermal drying and curing
✔ Anti-caking surface coatings (clays, fatty amines)
📌 No metallurgical behavior applies (ionic compound)
Thermal & Chemical Behavior
Thermal Decomposition:
Loses crystal water above ~100–120 °C
Converts to dicalcium phosphate at higher temperatures
Further heating forms insoluble calcium phosphates
Chemical Reactivity:
Highly reactive in soil
Rapid phosphorus availability
Calcium buffers excessive soil acidity
Key Agronomic Characteristics
✔ High phosphorus concentration without nitrogen
✔ Immediate phosphorus availability
✔ Supplies calcium as a secondary nutrient
✔ Ideal where nitrogen is supplied separately
Manufacturing & Processing
Produced through full acidulation using phosphoric acid:
✔ Beneficiated phosphate rock
✔ Wet-process phosphoric acid
✔ Acidulation reaction
✔ Granulation, drying, screening, and coating
Key Process Controls:
Acid concentration
Rock reactivity
Free acid content
Granule moisture
Available Forms
Granular TSP (field application)
Powdered TSP (fertilizer blends & industrial use)
Bulk TSP (plantations & large farms)
Applications
Agriculture: Pulses, oilseeds, cotton, sugarcane, vegetables
Best suited for: Nitrogen-rich soils, legume crops, calcareous soils (localized effect)
Industrial: Phosphate chemical feedstock, animal feed phosphates (after processing), intermediate for compound fertilizers
Advantages of TSP
Agronomic:
✔ High P₂O₅ without nitrogen
✔ Immediate crop response
✔ Calcium improves root development
✔ Excellent for balanced nutrient programs
Commercial:
✔ Lower cost than MAP/DAP per unit phosphorus
✔ Simple, single-nutrient composition
✔ Excellent blend compatibility
Limitations & Considerations
No nitrogen or sulfur content
More hygroscopic than DAP
Dust issues if poorly granulated
Less suitable for fertigation systems
TSP vs DAP vs MAP
| Parameter | TSP | DAP | MAP |
|---|---|---|---|
| N (%) | 0 | 18 | 11 |
| P₂O₅ (%) | 46 | 46 | 52 |
| Calcium | High | Trace | Trace |
| Soil Reaction | Acidic | Slightly alkaline | Acidic |
| Blend Compatibility | Excellent | Moderate | Excellent |
Why Choose TSP?
✔ Pure phosphorus source
✔ Ideal for legume crops
✔ Provides calcium supplementation
✔ Cost-effective phosphorus fertilization
✔ Flexible nutrient planning
Storage & Handling
Store in dry conditions
Avoid prolonged humidity exposure
Use moisture-resistant bags
Follow FIFO inventory practices
Soil Suitability Summary
| Soil Type | Suitability |
|---|---|
| Neutral soils | Excellent |
| Slightly alkaline soils | Good |
| Highly alkaline soils | Moderate |
| Acidic soils | Use cautiously |