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Sun Haiquan
SINOMA
Decreasing Energy
Consumption in Cement
Plant
Challenges for Cement Industry
＊ Resources
＊ Energy
＊ Environment
Challenges for Cement Industry
Market pressure for low cost
Greenhouse gas emission
Stricter environment Act for SOx & NOx
High efficiency and low
emission cement plant
Typical Chinese Cement Plant
Capacity : 5500 t/d
Altitude : ～600 m；Cement Type : OPC
Raw Material Grindability : moderate
Raw Material Burnability : moderate
Coal Quality : Qnet,ad≥5200 kcal/kg
Technical Target
Designed Fuel Consumption : ≤680 kcal/kg
Power Consumption up to Clinker : ≤54 kWh/ t
Power Consumption for Cement : ≤75 kWh/ t
Alternative Fuel Usage : 30％
NOx Emission : ≤320 mg/Nm3（NO2@10%O2）
6-stage preheater
more energy-efficient than 5-stage preheater
exhaust gas temperature ≤270℃,
Pressure drop ≤5200Pa.
Technology for Energy Conservation and Emission Reduction
Decrease Fuel Consumption
Technology for Energy Conservation and Emission Reduction
C1 gas duct换热对比
185
141
115
100
23
189
147
105
91
25
178
140
103
87
25
0
20
40
60
80
100
120
140
160
180
200
C1 C2 C3 C4 C5
换热对比（℃）
改进型喷腾预热器 原喷腾预热器 新三代
C4 gas ductC3 gas ductC2 gas duct
Effect:
compared to conventional preheater
C1 outlet temperature decreases 30 °C;
heat consumption decreases 10 ~ 15 kcal / kg.cl;
Computer thermal simulation results
High solid/gas ratio spout turbulence heat exchange technology
Decrease Fuel Consumption
Technology for Energy Conservation and Emission ReductionDecrease Fuel Consumption
Standard Modularization Design
Fourth Generation Cooler : Walking Floor
TC air flow control valves distribute on whole grate,
for Auto-Controlling of Constant Flow
keep air flow constant by stabilizing
pressure difference of each grate
unit.
Decrease Fuel Consumption
Fourth Generation Cooler : Air Flow Control Valve
Technology for Energy Conservation and Emission Reduction
Decrease Fuel Consumption
Technology for Energy Conservation and Emission Reduction
Low wear
Easy maintenance
Modular design
Less spare parts.
Fourth Generation Cooler : New Grate Design
Decrease Fuel Consumption
Technology for Energy Conservation and Emission Reduction
Special labyrinth sealing between the grates to ensure no
clinker leakage.double seal
precision
casting
after 32 months
operation
Fourth Generation Cooler : Zero Clinker Leakage
Decrease Fuel Consumption
Technology for Energy Conservation and Emission Reduction
The pushing force of burner is >1500 m/s.
Axial air 300m/s
Swirl channel 160~180m/s
Cooling air 15~30m/s
Coal air 24~28m/s
• 6~7% Primary air
• Convenient to adjust the shape of flame
• long-lasting
High efficiency & low primary air burning
Decrease Fuel Consumption
Technology for Energy Conservation and Emission Reduction
Oxygen enriched combustion technology to inferior fuel
Benefits of oxygen-enriched combustion：
Substantial increase in the flame temperature
Accelerating he burning speed to promote complete combustion of
Reduce the ignition temperature of the fuel and burnout
reduce the waste gas volume thus to some extent reduce the fuel consumption.
Notes: 1. It works for low quality fuel and waste coprocessing.
2. Not help too much for high quality fuel.
Decrease Fuel Consumption
Technology for Energy Conservation and Emission Reduction
Stable Coating ZoneOutletZone
Calcining ZoneUpper Transition
ZoneSafe Zone Inlet Zone
Heavy Condition 恶劣条件
Magnesia Aluminate
Spinel brick
High Performance
Low Thermal
Conductivity
Brick
High Alumina
Spalling- resistance
Brick
Castable
Lower Transition
Zone
Castable
Magnesia
Aluminate
Spinel brick
Magnesia Hercynite
Spinel brick
Normal Configuration of kiln：
Refractory Optimization
Kiln
diameter[m]*
Lining thickness
[mm]
ISO – Mix VDZ – Mix
< 3,6 180 218 / 618 B218 / B618
3,6 – 4,2 200 320 / 620 B320 / B620
4,2 – 5,2 220 322 / 822 B322 / B622
> 5,2 250 425 / 825 B425 / B825
Recommendation for kiln lining thickness and brick mix
Kiln
Decrease Fuel Consumption
Technology for Energy Conservation and Emission Reduction
Others
High solid-gas ratio for pulverized coal conveying
Use of intelligent control technology to optimize the
operation
Improve the sealing of equipment will reduce the air
leakage and reduce the fuel consumption
Steady operation and high availability
Waste heat recovery power plant
………
Solutions for Cement Industry
6 stage Preheater
spout turbulence
Fourth Generation Cooler
High efficiency & low primary air burning
Refractory Optimization
Power Consumption in Cement Plant
Ball mill time ：＞100kWh/t·cement
VRM time : 85kWh/t·cement
New Target ：＜75kWh/t·cement
SectionkWh/t
Per sectionkWh/t.clinker kWh/t. cement
Ratio
(%)
Raw mill 15 23.2 17.4 22.6
Coal mill 25 4.1 3.1 4.0
Pyro system 26 26 19.5 25.6
Cement mill 27 27.0 35.1
Other 10 8.0 14.8
Total 75 100
Grinding tech improvement play the most
important role to reduce power consumption!
Sum power consumption of grinding section :
47.5kWh/t. cement, 62% of total power consumption
Decrease Power ConsumptionTechnology for Energy Conservation and Emission Reduction
Decrease Power Consumption
Technology for Energy Conservation and Emission Reduction
Configuration
Decrease Power Consumption
Technology for Energy Conservation and Emission Reduction
Item RP
system
VRM
system
Main motor ,kWh/t 7.2 7.5
Process fan, kWh/t 4.0 6.8
Separator, kWh/t 0.2 0.3
Elevator, kWh/t 0.8 0.1
Others, kWh/t 0.8 1.3
Total, kWh/t 13.0 16.0
Roller press final-grinding technology of raw meal
RP grinding system can save 3 to 4kWh/t.raw
meal comparing with VRM system generally.
Analysis of runing datas of 12 sets RP
grinding system: RP7.7kWh/t，
system13.6kWh/t.
• VRM which occupied 80% Chinese market share is
widely used 5000tpd projects because of its simple
process flow, high reliability and good drying capacity.
• Recently, raw meal roller press finish grinding system is
rising.
Decrease Power Consumption
Technology for Energy Conservation and Emission Reduction
Comparison of raw grinding system
System Roller press VRM Remarks
specific
power
consumption
kWh/t 12~14 15~17
middle grindability％ 80～100 100
Wear rate ,g/t 0.5~3
Surface
Welding
2~6
Roller+Table
lifetime,h 7000 7000 middle abrasion
Drying capacity ,% 5~7 7 5 stage preheater
feed size,% D90=60mm D90=80mm
process flow raletively
complicated
relatively
simple
large-size difficult easy
availability normal higher
Performance
after wear
stability bad good
Capacity bad good
Decrease Power Consumption
Technology for Energy Conservation and Emission Reduction
Optimization of roller mill for Cement Grinding
improvement
Roller Shape
high efficiency separator
high performance wear material
adjustment
roller pressure
table rotating speed
dam ring height
cement quality
efficiency
basically equivalent to the product from ball mill
lower to 30 kWh/t cement
Decrease Power Consumption
Technology for Energy Conservation and Emission Reduction
Optimization of roller mill for Cement Grinding
improvement
Roller Shape
high efficiency separator
high performance wear material
adjustment
roller pressure
table rotating speed
dam ring height
cement quality
efficiency
basically equivalent to the product from ball mill
lower to 30 kWh/t cement
Decrease Power Consumption
Technology for Energy Conservation and Emission Reduction
Upgrading Existing Ball System
System Pre grinding Mixed grinding Combined
grinding
Semi-finish
grinding
Flow sheet
Capacity upgrade 30～70% 70～200%
Energy saving 10～20% 20～30%
Decrease Power Consumption
Technology for Energy Conservation and Emission Reduction
Waste Heat Recovery Power Plant
SP Boiler
Outdoor Pipeline
Cooling Tower & Pump
TG BuildingDemi-water
AQC Boiler
Others
High efficiency fan and VFD
Use of intelligent control technology to optimize the operation
Improve the efficiency of cyclone for raw meal grinding
system to lower the raw grinding power consumption
Decrease pressure drop of preheater………
Technology for Energy Conservation and Emission ReductionDecrease Power Consumption
1、 Low-NOx Burner
2、Tertiary air staged combustion
3、SNCR
Air staged combustion Calciner
Technology for Energy Conservation and Emission ReductionTechnology roadmap to reduce NOx emission
1、 Modification in Preheater
2、Add chemical (CaO, Ca(OH)2) in the preheater
3、Scrubbing Plant
Technology for Energy Conservation and Emission ReductionTechnology roadmap to reduce SOx emission
Reference 5500tpd cement plant applied 6 stage preheater system, two support kiln,
fourth generation cooler with middle roller crusher, low primary air burner. Starting up
on June 21st 2016, first clinker on June 29th 2016, performance test during 19th to
22nd of July 2016.
Technology for Energy Conservation and Emission ReductionApplication of some of the solutions
Kiln feeding rate:375t/h
Technology for Energy Conservation and Emission ReductionApplication of some of the solutions
Kiln feeding rate:400t/h
Technology for Energy Conservation and Emission ReductionApplication of some of the solutions
Performance guarantee:
Production Capacity : 5500t/d
Clinker Strength (28 days) : 58MPa
Clinker Strength (3 days) : 28MPa
Clinker Fuel Consumption : 686kCal/kg.clinker
Clinker Power Consumpiton : 52kWh/ton.clinker
NOx Emission(with SNCR) : no more than 320/Nm3
NOx Emission(without SNCR) : no more than 550/Nm3
Technology for Energy Conservation and Emission ReductionApplication of some of the solutions
Actual Performance
Production Capacity : 5900-6000t/d
Clinker Strength (28 days) : 58.1MPa
Clinker Strength (3 days) : 32.6MPa
Clinker Fuel Consumption : 662.9kCal/kg.clinker
NOx Emission (with SNCR) : 260±30/Nm3
NOx Emission (without SNCR) : 498/Nm3
Including bag house exhaust fan (2.16kWh/t.clinker), the power
consumption in pyro-system section is 22.3kWh/t.clinker.
Technology for Energy Conservation and Emission ReductionApplication of some of the solutions
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