Waste Heat Recovery

Waste Heat Recovery System (WHRS) in cement plant is proven practice for power generation and it is constructed by utilizing the waste heat from the gas of clinker cooler vent and pre-heater outlet to generate electricity power. The operation of Waste Heat Recovery Power Plant shall not affect the normal cement production.

We provide waste heat recovery system which is tailored design considering following parameters:

No effect to cement line
No additional fuel consumption
Maximum utilization of the waste gas
Lowest power/water consumption
Optimum set of equipment arrangement and selection
Stable operation
Less land occupation & structure cost
Low noisy and long operation life time
Reliable, high applicability, simple operation and maintenance

We use reliable new technology to increase power output and to make the Waste Heat Recovery Power Plant with maximum efficiency

Main Equipment of WHR System:

Boiler, Turbine and Generators
Cooling water system
Chemical water treatment system
Water supply and sewerage system
Electricity
Process automation
Fire-Fighting & Fire alarms
Civil Work design

Our scope for design and supply of equipment and materials

Boiler: GB standards
Steam Turbine: GB standards
Process water/steam pipes and valves: GB standards
Other Mechanical Equipment: GB standards
Mechanical Materials: GB standards
Electric Generator: IEC standards
LV/MV Switchgear: IEC standards
Other Electrical & Automation Equipment: IEC standards
Electrical Materials: IEC standards

WHR power plant is based on the waste heat from the clinker kiln. When there is fluctuation of the clinker kiln, the power generation of WHR power plant is varied. When there is waste gas temperature fluctuation, the steam produced by the waste heat recovery boilers will be fluctuated accordingly. The selection of equipment for waste heat recovery power plant should suit all the fluctuation of gas parameters and the thermodynamics.

We carefully study the existing installed cement production process and understand thermodynamics system in order to fulfill the operation requirements, save energy and to achieve best efficiency of waste heat recovery system

AQC boilers are installed next to the cooler side of the cement lines, for producing main steam and LP steam and hot water, and a precipitation chamber is set up at the bottom of boiler to alleviate the boiler abrasion. SP boilers are installed besides the preheater tower, for producing main steam and LP steam.

Thermodynamic system:

Water after being de-aerated is pumped to AQC boiler’s hot water stage.
The outgoing hot water from AQC boiler’s hot water stage is divided into four parts:

part of them is used as feed water of AQC boiler’s main steam stage,
part of them is used as feed water of AQC boiler’s LP steam stage,
part of them is used as feed water of SP boiler’s main steam stage,
part of them is used as feed water of SP boiler’s LP steam stage.

The superheated steam produced by SP boilers and AQC boilers merge together and introduced to the turbine to drive the turbine for power generation. LP steam from SP boilers and AQC boilers merge together and be introduced to the turbine as supplement steam. Exhaust steam of turbine after work is condensed to water, and then pumped to a deaerator, thus a complete thermodynamic circulation system form.

The characteristics of the system are as follows:

In order to make best of the waste heat, the AQC boilers adopt multi-stages heat receiving surface.
To make sure power station failure will not affect cement production, each waste heat boiler is equipped with bypass gas duct and damper. Once waste heat boilers or sub-station fail, the waste heat boilers can step out from the cement production system so the normal cement production operation can be guaranteed.
The boilers are vertical type, which can save floor space, reduce air-leakage and increase heat recovery rate, meanwhile, proper solution solve boiler abrasion, ash clogging, etc.
The deaerator adopts vacuum type, which assures deoxidation sufficiently.
Since the grain of dust at outlet of kiln is large, a precipitation chamber is installed at the AQC boiler’s bottom, which make the large grain settled down to light the scouring and wearing to boiler.
The WHR operation is controlled by DCS, which can guarantee the power station’s safety and stabilization.