My presentation video on Phosphorous Removal Technology. Approved by Ass Prof. Sukra Raj Poudel, IOE, Pulchowk Campus, Lalitpur, Nepal. Date Presented: 2018/06/20 Youtube link: https://www.youtube.com/watch?v=l1KgrKeYTew

1. Phosphorous Removal
Technologies
Tutor:
Asst. Prof. Shukra Raj Paudel
Department of Civil Engineering
IOE, Tribhuvan University
2018-06-20
1
Group Members:
Sujan Acharya, 169
Sujan Lamichhane, 170
Sulav Sigdel, 171
Suman KC 172
Suman Rijal,173
Suman Subedi,174

2. Objectives Of Presentation
From this presentation, Students will be able to understand:
 Phosphorous content in wastewater
 Effectes of Phosphorous in water
 Phosphorous removal technologies
 Comparisons between different technologies
2

3. Presentation Outline
 Introduction
 Working Principle of Treatment Process
 Applicability
 Limitations
 Conclusion
3

4. Introduction
 Phosphorous is a chemical element with symbol P and
atomic number 15.
 Phosphorous is essential nutrient for plants.
 It is a part of DNA-molecules which stores energy. But its
presence in large extend is harmful to human and aquatic
beings
source: www.oped.edu
4

5.  One question arise in our minds.
Why is it necessary to remove phosphorous if it is
essential for life?
Phosphorous is good for plant growth, human cell formation but
it is not good for aquatic animals.
• Phosphorous causes Eutrophication
• If it is present more, it will cause Taste and Odour Problem
• Increases irrigation water cost
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Introduction(Contd)

6.  Phosphorous Cycle
source:migardener.com
6

7. Types Of Phosphorus:
1. Orthophophates
H3PO4 , H2PO4− , HPO4
- PO4 ---
In the pH range of wastewaters(around 7), the
dominant forms of orthophosphate are H2PO4-, ,
HPO4--. As the Ph increases, the equation moves
toward the formation of P04 ---
7

8. Types Of Phosphorus(Contd):
2. Condensed(Polyphosphates)
When H3PO4 is heated, it decomposes, losing
molecules of water forming the P - O - P bonds. The
process of losing water is called condensation.
8

9. Types Of Phosphorus(Contd)
3. Organic Phosphates:
When organic compounds containing P are
attacked by microorganisms, they also undergo
hydrolysis into the organicphosphate forms.
 Typical municipal waste : 10 – 15 mg/L as P 30 %
from human waste + 70 % from industries
(mostly in the form of polyphosphates)
9

10.  Eutrophication
• From Greek word ‘Eutrophos’ meaning ‘well-nourished’
• Oxygen depletion
• Low light penetration
• Loss of Aquation life
• Aesthetic problem
source:teacherspayteachers.com
10
Water
becomes
enriched with
minerals
Induces excessive
growth of plants
and algae

11.  Reaction of Eutrophication
CO2 + NO3
- + HPO4
-- + H+ +H2O C106H263O110N16P +
O2 (Nitrate) (Algae)
11
source:uk.businessinsider.com

12. Types Of Treatment Process:
12
Chemical
Treatment
Biological
Treatment
Their
Combination

13. Working Principles of Treatment Process
1. Chemical Process of Phosphorous Removal:
 Common precipitation cations used are Ca, Al and Fe.
I. Precipitation by Calcium:
Calcium is usually added as lime (Ca(OH)2 ). The reaction is
represented as:
Ca + PO4 + OH- Ca10 (PO4) 6(OH)2(s)
 pH has to be elevated between 10.5 and 11 to get effective P
removal.
13

14. II. Precipitation by Al and Fe
Phosphate precipitation of by Al
Al3 + HnPO4 AlPO4(s)+nH
Phosphate precipitation of by Fe
Fe3 + HnPO4 FePO4(s)+nH
In general, with Ca, Al or Fe addition to
precipitate PO4 3-, higher pH is favorable
(more in PO4
- - - as opposed to HPO4
- - or
H2PO4
- ).
14

15. Working Principles of Treatment
Process(Contd)
2. Biological Phosphorus Removal(BPR)
This is achieved by:
 Growing microorganisms that are capable of storing
phosphorus intracellularly as polyphosphate.
 The growth of Phosphorus-Accumulating Organisms
(PAOs) is favored by subjecting the activated sludge
to a cycle of anaerobic and aerobic conditions.
 Phosphorus is then removed by wasting excess
sludge.
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16. 2. Biological Phosphorus Removal(BPR) (Contd)
 The reactor configuration consist of an anaerobic
tank and an activated sludge tank.
 The retention time in the anaerobic tank is about
0.5 to 1 hours.
 Amount of phosphorous removed can be estimated
from bsCOD( biodegradable soluble COD)
16

17. 2. Biological Phosphorous Removal(BPR) (Contd)
source:www.uni-due.de 17

18. E-BPR
 Enhanced- Biological Phosphorus Removal
 Still under development
 Better Phosphorus Removal Efficiency
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Food for PAO
• Volatile Fatty Acid(Acetic,
Propionic)
• Anerobic Condition
Digestion
• Breakage of
Phosphorous bond
from waste water
• Aerobic Condition

19. source:unacademy.com 19

20. Applicability Of Technologies
Applicability of two processes of Phosphorous removal can be
explaind by studying comparisions between two processes.
 Comparision based on Effluent quality
Chemical Phosphorous Removal has higher effluent quality
 Comparision based on Sludge production
Biological Phosphorous Removal has lower sludge production
 Comparision based on Needed Plant Volume
Biological Phosphorous Removal will need less plant volume as the
volume of anaerobic zone is reduced. 20

21. Applicability Of Technologies(Contd)
 Comparision based on Energy and Chemical Consumption
Chemical P Removal will, of course, comsume less
energy and chemical.
source:www.chemeng.lth.se 21

22. Limitations
 Successfully operated on Large-Scale
 But on small-scale low budget P-removal, problems arise.
 Economy
 Diffifulty in Sludge Removal
 Shortage of Skilled Manpower
 Maintenance Problems
 We cannot expect same efficiency by downgrading
large scale P-removal into small scale 22

23. Concluding The Presentation
 Method of treatment system mentioned in this
presentation are outdated.
 Search for simple and effective way of treatment is
important issue around the globe.
Technologies in their development stage
• Wetlands Incorporating Active Media
• PhosphoReduc Filter System
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24. Thank You, Class
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