Energy from Waste Water Sewage Sludge in Lebanon - Ecorient 2013

Energy from Wastewater Sewage Sludge in Lebanon

Transforming a Waste Disposal Problem into an Opportunity

Ecorient – June 2013

Council for Development & Reconstruction

Table of contents

‐ Objectives of the Study, Slide 4‐ Anaerobic Digestion & CHP Technology Review, Slides 5 to 12‐ AD General Guidelines for Future WWTP, Slide 13‐ Project 1 to Project 7 Definition, Slides 14 & 15‐ Scenario 1: AD from WWTP proper Sludge only, Slide 16‐ Scenario 2: AD with Added Sludge, Slide 17‐ Scenario 3: AD with Added Sludge & Co‐Substrates, Slide 18‐ AD Economics, Slide 19‐ Summary of Findings, Slide 20‐ Challenges & Recommendations, Slide 21‐ Conclusion, Slide 22

Objectives of the Study

• Issue Anaerobic Digestion ‐ AD technology general guidelines for future WWTP projects in Lebanon

• Evaluate Energy potential at 7 identified WWTP sites where sludge AD is feasible

• Evaluate options to maximize Energy production:a‐ Sludge imported from WWTP within 25 Kmb‐ Co‐digestion using local substrates

identified in the area during the National Bioenergy National Plan

Anaerobic Digestion Technology: Principle & Requirements

• Anaerobic digestion is a process in which organic matter from wet organic wastes (ie. Waste water sludge, liquid & solid manure, food processing wastes, slaughterhouse residues, agriculture residues etc.) is converted into Biogas by bacteria in the absence of oxygen.

• The Biogas including 60% Methane (CH4) is then collected and may be used to generate Electricity & Heat (1 Nm3 Biogas 0.6 liters LFO).

• Biogas reduces emissions by preventing methane release in the atmosphere. Methane is 21 times stronger than carbon dioxide as a greenhouse gas.

• In addition, the AD process creates potentially valuable by‐products, such as High Ammonia content fertilizer from hygenized sludge, and/or liquid with available nutrients.

• Finally the AD process has the advantage of Odor Control & Sludge volume reduction to (1/3).

Sludge Anaerobic Digestion Operational Parameters

1 Ton Organic Matter Destroyed

From 20 Nm3 to 900 Nm3 of Biogas depending on feedstock & AD design

+ Valuable Fertilizer

How an Anaerobic Digester Works ?

5 – 20 Days, Temperature Dependent

What an Anaerobic Digester looks like ?

Substrate Inflow Effluent

Substrate

Effluent Gas

Ground injection pipe

Ground sludge pipe

Fluid Zone

Sludge Zone

Mixing Zone

Biogas

Basic Anaerobic Digestion System Flow Diagram

Basic Combined Heat & Power Biogas Engine Gen‐set Diagram

Hot Return Water

Cold Supply Water

Pump

Exhaust Stack

CO2 Recovery

Secondary Exhaust Heat Exchanger

Selective Catalytic Reduction Exhaust after Treatment

Exhaust Silencer Heat Exchanger

Biogas Gensetwith Heat Recovery

Exhaust Oxidation Catalyst

Electric Utility

Exhaust Line

Electric Output

Switchgear

Biogas Supply

Jacket Water & After‐cooler Heat Exchangers

100 MWh/Year Primary Energy : Valorization Methods Comparison

Biogas Combined Heat & Power CHP Gas Engines Gen‐Set

39 MWh/Year Electrical Energy +

41 MWh/Year Heat Energy=

80 MWh/Year Total Energy

Gas Engines Gen‐Set (Electricity Only)

39 MWh/Year Electrical Energy(Heat Energy is Wasted)

Boiler (Heat Only)

85 MWh/Year of Heat Energy

Scale Requirements for Anaerobic Digestion

Feedstock (Tons / Year ) to produce 1 MWe

25,000 to 60,000 (depending on feedstock)

AD Technology General Guidelines for Future WWTP Projects

Medium to Large WWTP Projects in Lebanon

86%

7%7%

WWTP Distribution by Size

Less than 100,000 PEBetween 100,000 PE & 200,000 PEGreater than 200,000 PE

Name PE

100,000 to 200,000 PE

1 Nabatieh 100,0002 Tibnine & Chakra 100,0003 P7 ‐ Baalbek 100,000

4 West Beqaa (Jib Jenine + Saghbine) 100,000

5 Timnine El Tahta 100,0006 Zahle 150,0007 P3 ‐ Aabde 185,000

> 200,000 PE

1 P2 ‐ Tyr 250,0002 P6 ‐Majdal Aanjar 300,0003 P4 ‐ Sarafand 325,0004 P5 ‐ Saida 390,0005 Kessrwan 505,0006 Ghadir 800,000

7 P1‐ Tripoli 1,000,000

8 Bourj Hammoud 2,000,000

7 Identified AD Feasible WWTPWWTP PE Co-Substrates MW

P1

Tripoli 1,000,000 N.A.

3.1 MWJbeil 50,000 N.A.

Batroun 30,000 N.A.Chekka 24,000 N.A.

P2 Tyr 250,000 N.A. 0.9 MWTibnine & Chakra 100,000 N.A.

P3Aabde 185,000 Wheat Residues

1.4 MWBakhoun 48,000 Animal ManureMechmech 68,000 Food Industry Waste

P4

Sarafand 325,000 Wheat Residue

1.5 MWNabatieh 100,000 Yellow Grease

Kfarsir, Yahmour & Zawtar 35,000 Animal ManureFood Industry Waste

P5Saida 390,000 Slaughterhouse Waste

1.7 MWRas Nabi Younes 88,000 Wheat Residues

Olive cake Residues

P6

Majdal Aanjar 300,000 Wheat Residues

1.7 MWZahle 150,000

Animal ManureSlaughterhouse WasteFood Industry Waste

P7

Baalbeck 100,000 Milk Processing Co-products

1.4 MWTimnine El Tahta 100,000 Wheat Residues

Laboua 47,000 Animal ManureFood Industry Waste

Scenario 1: AD from WWTP proper Sludge Only

21,9175,579 4,129 7,253 8,703 6,695 0

54,27623,041

5,865 4,3407,625 9,150 7,038

0

57,059

0

20,000

40,000

60,000

80,000

100,000

120,000

MWh/Year Energy Production through CHP

Energy Production through CHP: Heat MWh/yearEnergy Production through CHP: Electriciity MWh/year

7.32 MW

75 %

% Self Generated Electricity

75 % 75 % 75 % 75 % 75 % 0 %

‐ 8,300 T CO2e/Year







Scenario 2: AD with Added Sludge from nearby WWTP

23,9687,217 6,029 8,940 10,772 8,333 3,964

69,22325,197

7,587 6,338 9,399 11,325 8,7604,168

72,774

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000


Energy Production through CHP : Heat MWh/yearEnergy Production through CHP : Electriciity MWh/year

8.88 MW

+ 9.4 %

+ 29.4 %+ 46.0 %

+ 23.3 % + 23.8 % + 24.5 %

+ 27.5 %

+ 0.0 %

+ 22.5 %+ 42.1 %

+ 25.6 % + 21.0 % + 22.5 %

+ 21.4 %

% Increase in Installed Capacity% Increase in Energy Production

83 %

100 %112 %

95 % 95 % 96 %




‐2,200 T CO2e/Year






Scenario 3: AD with Added Sludge & Co‐Substrates

23,9687,217 11,011 11,921 13,611 13,560 11,395

92,68325,197

7,587 11,576 12,534 14,309 14,255 11,979

97,437

020,00040,00060,00080,000100,000120,000140,000160,000180,000200,000


Energy Production through CHP Heat MWh/yearEnergy Production through CHP Electriciity MWh/year

+ 9.4 %

% Increase in Installed Capacity% Increase in Energy Production

+ 29.4 % + 166.7 % + 64.4 % + 56.4 % + 102.5 % + 187.5 %

+ 70.8 %


+ 0.0 %

11.68 MW

+ 22.5 %+ 89.8 % + 60.8 % + 53.3 % + 90.0 % + 189.4 %

+ 59.5 %

83 %

100 % 205 % 126 % 120 % 156 %









AD Economics

19.70

16.10 15.60 16.20

7.708.70

10.60 10.70

9.00 7.10

0.00

5.00

10.00

15.00

20.00

25.00

P3‐ Aabde P4‐ Sarafand P5‐ Saida P6‐ Majdal Anjar P7‐ Bekaa

Levelized Cost of Electrical Energy in $c/Kwh

$c/Kwh Scenario 2 $c/Kwh Scenario 3

Current Cost of Energy Production by EDL

Target Cost of Energy Production by EDL

Current EDL Tariff

Scenario 1: Sludge AD Only

(6 Plants)

Scenario 2 : Sludge AD withAdded Sludge(7 + 14 plants)

Scenario 3: Sludge AD with Added Sludge & Co‐Digestion

( 7 + 14 plants)Already Installed Generation

Capacity (Tripoli) 3.09 MW 3.09 MW 3.09 MW

Additional Generation Capacity 4.23 MW 5.79 MW 8.59 MW

Total Generation Capacity 7.32 MW 8.88 MW 11.68 MW

Electric Energy 54,276 MWh/y 69,223 MWh/y 92,683 MWh/y

Heat Energy 57,059 MWh/y 72,774 MWh/y 97,437 MWh/y

CO2 Reduction ‐ 20,500 T CO2e/y ‐ 25,700 T CO2e/y ‐35,000 T CO2e/y

Self Generation 75% 83% to 112% 83% to 205%

Levelized Cost of Electricity* N.A. 7.7 to 19.7 c/Kwh 7.1 to 10.7 c/Kwh

* The heat & the fertilizers that are produced are an added benefit that has not been priced

+ 21.4 % + 59.5 %

+ 27.5 % + 70.8 %

+ 25.4 % +70.8%

Scenario 3 represents 3% to 4% of Lebanon’s Bioenergy Potential

Findings Summary

Challenges & Recommendations• The future WWTP design must follow the general guidelines.• WWTP belonging to different Water Establishments must be able to

divert sludge from one plant to another under Scenario 2.• The Water Establishments to which the WWTP belong must have the

legal & administrative possibility to enter into agreements with third parties for acquiring the Co‐Substrates feedstock under Scenario 3.

• The WWTP that generate more then their Electrical Energy consumption must be enabled to evacuate the excess energy on the grid (ie: elaborate a customized Net Metering scheme).

• The Levelized cost of Energy Produced under Scenario 2 being higher than the target level of 14 c/Kwh , incentives will be required to proceed or we must stick to Scenario 3.

• The WWTP must have the legal & administrative possibility to sell the Heat Energy produced & the Fertilizers to neighboring end users.

• The AD technology requires a thorough technical monitoring in order to be effective. The Water Establishments must be allowed to collect money from the end users for the WWT service in order to finance the proper Operation & Maintenance of these plants.

Conclusion

• There is a valuable opportunity to do the following in one stroke:

‐ Produce Renewable Energy‐ Recycle Waste into Fertilizers‐ Reduce Emissions‐ Reduce Fuel consumption‐ Solve a Waste Disposal Problem‐ Save Money‐ Preserve our Environment

What are we waiting for ?

Energy from Waste Water Sewage Sludge in Lebanon - Ecorient 2013

Engineering

Transcript of Energy from Waste Water Sewage Sludge in Lebanon - Ecorient 2013