Cogeneration Of Power

• 1. COGENERATION OF POWER
  A Case Study of Cement Industry
  

2. Cement Industry: An Introduction
An energy intensive industry consuming about 4GJ per tonne of cement produced.
In dry process cement plants, nearly 40 percent of the total heat input is rejected as waste heat from exist gases of pre-heater and grate cooler.
In India, the industry accounts for 10.3% of total fuel consumption in the manufacturing sector.
3. Process Description
Procurement of Raw Materials
Raw Milling Preparation of raw materials for the pyro-processing system
Pyroprocessing pyroprocessing raw materials to form portland cement clinker
Cooling of portland cement clinker
Storage of portland cement clinker
Finish milling
Packing and Loading
4. Wet Process Raw Material Grinding
Limestone
Water
Kiln
Crusher
Raw Mill
Slurry Basin
Storage Yard
Slurry Tank
Additives
Clay basin
Water
Clay
Wash Mill
5. Dry Process Raw Material Grinding
EP
Dryer
Preheater and Kiln
BT
ST
Storage
Raw Mill
Dryer
Heat generated
BT Blending Tank
ST Storage Tank
EP Electrostatic Precipitator
6. Average Energy Consumption in a1 MTPA Cement Plant
Thermal Energy: 0.80 Million Kcal/Tonne Clinker
Electrical Energy: 100 KWH/Tonne cement
Coal Requirement: 2,00,000 Tonnes/Year
Power Requirement: 20 MW (At 70% Load Factor)
7. Total Power & Captive Power Requirement for Various Plant Capacities
* Taking Captive Power Requirement @ 30% of Total Power for Maintaining Continuous Production from Kiln
8. PREHEATER EXIT GAS, 300 400OC, 180-250 KCAL/KG
COOLER EXIT GAS, 200 300OC, 80-130 KCAL/KG
SOURCES OF WASTE HEAT
9. COGENERATION POTENTIAL IN INDIA
Plants that are amenable for Cogeneration : 40
Total Cogeneration Capacity, MW : 160
Expected Power Savings : Upto 25 30% of Total Power Requirement can be achieved in a cement plant
10. CO2 Reduction Possibilities
CO2 Reduction Potential : 1.50
(Million Tonnes per Year)
Percentage Reduction as compared to emissions due to electricity consumption : 18
11. Power Generation through Waste Heat Recovery
Utilization of waste heat from the Pre-Heater gases for power generation.
Utilization of waste heat from AQC.
Utilizing 40% Thermal Energy discharging into the atmosphere.
Producing about 30% of Total Power Requirement for the Plant itself.
Reducing CO2 amount in the atmosphere.
12. Technical Consideration For Cogeneration Schemes
Availability of waste heat for cogeneration
Location of Waste Heat Boiler
Suitability of Waste Heat Recovery Boiler
Maximum Flue Gas Temperature
Quantity of Heat Recovery
Type of Boilers, Turbines and Condensers
De-dusting Arrangement
Availability of Water
13. Recent Developments
Improved Waste Heat Recovery Boiler (THERMOWIR)
Removing 60% (48-60 gm/Nm3) dust from the gases reducing load on existing ESP
Higher efficiency compared to conventional Heat Exchangers
14. Recent Developments
Modified Rankine Cycle System KALINA Cycle
Uses Binary fluid of Ammonia and Water
Efficiency gains of upto 50% for low temperature (200-280oC) and upto 20% for higher temperature heat sources compared to rankine cycle
15. Recent Developments
Organic Rankine Cycle (ORMAT Energy Convertor (OEC))
Uses organic fluid as working medium instead of steam
Suitable for much lower temperature heat sources as organic fluid has a much lower boiling point as compared to water.
16. 17. Case Study: 1.2MTPA, 4-Stage Preheater Cement Plant
18. Estimated Cogeneration Potential
19. Barriers in Adoption of Cogeneration Technology
Technical Barriers
Financial Barriers
Institutional Barriers
20. Technical/Technological Barriers
Non Availability of Proven technology indigenously.
Design of waste heat recovery boiler suitable to withstand high dust load in the waste gases.
High performance risk due to demonstration.
21. Financial Barriers
Large Capital Requirement and financial constraints.
Viability remains to be established.
High cost of technology and access to funds.
Depressed cement marketing scenario.
22. Institutional Barriers
Lack of incentives for adoption of technology.
Lack of capacity building efforts resulting in lack of operating experience and confidence level.
23. THANK YOU!