1. T.K.Haldar & P.R.Mohanty Heavy Water Board Dept of Atomic Energy
Uranium Recovery from Phosphoric Acid – promising Hydro-metallurgical application of Solvent Extraction
T.K.Haldar & P.R.Mohanty
Heavy Water Board
Dept of Atomic Energy
Solvent Extraction Revisited: IIP-IIChE:NRC, New Delhi , February 2010

2. National Priority Energy Security Food Security GDP Growth 6.5%-7.5%
POPULATION
1.1 Billion

3. Food Security Projected Growth rate : 6.5% – 7%
Rising Fertilizer Consumption
P2O5 Consumption : more than 30 lakh tpy
Equivalent to 1000 MT Uranium per year
1000 MT Uranium is let out to agricultural land every year
Accumulation is cause for Concern
Can be addressed if Uranium is removed at source i.e. Phosphoric acid

4. Energy Security Current Power demand: 250 GWe
Current Power generation: 200 GWe
Nuclear : 4.4 GWe
Expected demand in 2050 :1260 GWe
Projected share of Nuclear Power : 670 GWe
Quantum jump in Nuclear power generation primarily to reduce carbon emission
Needs Augmentation of Uranium resources besides exploiting abundant Thorium resources

5. Indian Nuclear Option Indigenous PHWR : 13,000 MW by 2018
Fuel : (Indigenous + Imported)
Imported PWR/LWR
40,000 MW by 2030
Fuel : (Imported)
Indigenous FBR
400,000 by 2050
Fuel (Indigenous U, PU & Th)

6. Why Uranium from Phosphoric Acid
Cleanup of Phosphoric Acid & lessen environmental load
Inadequate mineral Resource
Quality
Quantity
Considering Indian mineral sources U-recovery from Phosphoric Acid make economic sense

7. Indian Perspective Energy Security Food Security Nuclear Comunity
POPULATION
U in Phos. Acid
U to Nuclear Fuel Cycle
Nuclear Comunity

8. Technology Status & Options
Global scenario
SX Technology deployed & proven
No known operating plant since 1999
Technology can be fine tuned for cost effectiveness using previous experience
Indian scenario
Comprehensive Technology Development, Demonstration & Deployment
Credible approach towards programme implementation for economic viability

9. Comprehensive Approach
Technology development in all related fields for large scale industrial deployment.
Technology initiative encompasses wide ranging and multi-dimensional issues.

10. Research, Development, Demonstration & Deployment (RD3)
Technology for Uranium from Phosphoric Acid
Solvents & other inputs
Solvent Extraction
Solid - liquid & Liquid-liquid Devices

11. SX Process Development
PROCESS CHEMISTRY
PROCESS DEVELOPMENT
URANIUM FROM PHOSPHORIC ACID
PROCESS EQUIPMENT
ENGINEERING CHALLENGES
SAFETY & ENVIRONMENT
ECONOMIC FEASIBILITY

12. SX Chemistry for U-recovery from Phosphoric Acid
Extraction
2(RH)2(aq)+UO2(H2PO4)2(aq) <=> (R2H)2UO2(aq) +2H3PO4 (aq)
(R2H)2UO2 (aq) <=> (R2H)2UO2 (org)
Stripping
(R2H)2UO2 (org) <=> (R2H)2UO2 (aq)
(R2H)2UO2 (aq) + 2H3PO4 (aq) <=> 2(RH)2 (aq) + UO2(H2PO4)2

13. Metal Extractant – D2EHPA
CH2CH3 |
CH3CH2CH2CHCH2O O P
CH3CH2CH2CHCH2O OH
Structure of D2EHPA
RO O---H ―O OR
P P
RO O― H---O OR  
Hydrogen bonded dimer

14. D2EHPA Dimeric Anion P O - H
2EHO
O2EH P O H
2EHO
O2EH

15. U IN TETRAHEDRAL D2EHPA MATRIXO H
2EHO
O2EH U O U

16. PROCESS SCHEMATICS SX 1ST CYCLE SX 2ND CYCLE WPA PRODUCER PRODUCT
SOLVENT REGENERATION
SOLVENT REGENERATION
SX ST CYCLE
SX ND CYCLE
FEED PRE-TREATMENT
POST TREATMENT
RM RECOVERY
WPA PRODUCER
PRODUCT

17. ACID PRE-TREATMENT FLOCULATED & FILTERED ACTIVE CARBON TREATED RAW WPA
OD : 0.5
OD : 0.05
OPAQUE

18. Process Issues Feed acid profile Pre & Post treatment requirement
Solvent mix / selection
Extractant, Diluent, Synergistic agent, Modifier etc
Choice of Stripping agent
Process control inputs
Waste & Effluents

19. Process Development MINI SCALE LAB SCALE DEMONSTRATION SCALE
BENCH SCALE

20. Process Development Studies
Feed Acid grades (% P2O5)
28%
42%
54%
No. of Sources 5 3 2
Qty Evaluated, M3
500
100 50
Study hours Clocked
10000
2000
1500
Solvent cycles encountered
4000
1000

21. Search For Right Solvent(s)
Promising molecules
Short listing (Screening & Selectivity) – in isolation and in synergistic combinations with other molecules
Qualifying the short listed species for initial evaluation
Selection of potential candidates for further development

22. Identified Solvents, Quality & availability
Primary Solvents
D2EHPA , TBP , TOPO , TAPO, DNPPA
Quality
Nuclear grade purity
Impurities in ppm level detrimental
Secured Availability
In-house Capability
100 MTPA D2EHPA, 190 MTPA TBP, 40 MTPA TOPO / TAPO / DNPPA

23. Development of Solvent Production Capability
Process Chemistry / Synthesis route
Process design
Equipment Selection & detailed engineering
Sound O&M Practices
Quality Assurance
Emissions and Effluents
Safety & Environment
User Acceptability & Cost Competitiveness

24. Industrial Scale Production Facility
The Journey
Lab Scale
Bench Scale
Pilot Scale
Industrial Scale Production Facility

25. Process Equipment Solid-liquid Separation
Belt Filter
Clarifier

26. Process Equipment Liquid-liquid Contactors
Mixer-Settler
Centrifugal Extractor
Rotating disc Column

27. Engineering Challenges
Materials of construction
Plant lay out
Regulatory compliances
Seamless integration with conventional Fertiliser Industry
Economics

28. Environmental Issues Effluent Management Local Statutory requirement
Radiological Monitoring and Protection

29. Taking a Call by Indian Nuclear Community
Concern for environment
voluntary, not regulatory
Potential Energy Resource
Exploitation Vs. Wastage
Investment Decision
Economic & Strategic
Challenge for Nuclear Community
Growth of SX - Process

30. Thank You