Liyan Xinjinfeng Cement Co., Ltd. was established in 2006 as a subsidiary company of Jiangsu Jinfeng Cement Group and specialises in production and sales of cement and clinker, pure low temperature waste heat power generation, and civil construction services.
The retrofit brought 504kW power savings equivalent to an annual cost saving of 2 million RMB ($27,000).
The challenge
Liyang Xinjinfeng’s cement line had a capacity of 5000t/d with a maximum of 7000t/d. The Kiln ID fan in this line worked under over current and over rated power conditions with high power consumption and poor safety. The actual operating efficiency of this fan was low.
The customer invited Howden to conduct a performance test of the Kiln ID fan and complete a retrofit to reduce the safety risk, improve efficiency and ultimately reduce energy costs. The original fan had been in operation since 2010 and was no longer meeting the design parameters.
The solution
In early 2021, the original fan was removed and the new refurbished fan installed during a planned overhaul period. The full project was completed and put into production within 4 months.
The retrofit consisted of major work being done to the fan body; the fan rotor, housing, intake box, inlet damper, coupling, bearing support and coupling shield were all replaced.
The existing motor remained in place and the original foundation did not need to be moved which meant the original anchor bolts were used and only a small area of partial modification was made.
The original inlet and outlet air ducts were used with new connection ducts installed on site which connected the original air ducts and the fan. The new fan impeller adopts a composite wear-resistant lining plate to enhance the wear-resistant performance of the impeller.
The outcome
Following the refurbishment of the fan, the performance parameters now meet the design values.
The full voltage efficiency was increased from 67.4% to 83.7% and output power of the switchgear is reduced from 3114kW to 2610kW. The retrofit brought 504kW power savings equivalent to an annual cost saving of 2 million RMB ($27,000).
The current of the motor was reduced below the rated current (197A) from 203A to 176A, which improves operational safety, and the power consumption per ton of feed is reduced by 15.1%.
“We are very satisfied with the performance of the modified fan and convinced by the tailored design. Based on the site status and our requirements, Howden provided a tailored proposal which has exceeded our expectations.” – Site Equipment Supervisor of Liyan Xinjinfeng Cement Co., Ltd.
|
Unit
|
Pre-retrofit
|
Post-retrofit
|
Raw material input
|
t/h
|
395
|
390
|
Inlet flow
|
m3/h
|
803258
|
855617
|
Total pressure
|
Pa
|
8194
|
8003
|
Inlet temperature
|
℃
|
230
|
210
|
Output power of switchgear
|
KW
|
3114
|
2610
|
Shaft power
|
KW
|
2634
|
2197
|
Total efficiency
|
%
|
67.4
|
83.71
|
Fan before retrofit

Fan after retrofit
