Hydrotech Systems

Air preheater and gas-gas heater cleaning
to a guaranteed restoration of efficiency
within a 48 hour plant shut down


Hydrotech Systems

Hydrotech Systems

Hydrotech Systems

Hydrotech Systems

Hydrotech Systems

Hydrotech Systems

Hydrotech Systems


Case Studies


Case Study 1
 
German Power plant, 300 MW Unit
 
2 x Ljungström 2CXS 275/2600
Element depth 2,100mm (700mm x1)
 
Cleaning Process before using Hydrotech prior to 2001:
 
Remove entire element layer, top side; transport to ground floor to be washed by conventional
hand-held means. In situclean of middle and cold side elements by conventional hand-held
means. Subsequentreinstatement of hot-endelements once satisfactory clean of remaining
elements has been carried out by labour-intensive wash. Alternatively, in situ clean of entire
preheater matrix from top-side only, incorporating the in-built soot-blowing mechanism.
 
Total duration of shut-down: 3 weeks
 
Clean Process since 2001 employing the Hydrotech System automated cleaning:
 
Day 1:
 
Arrival on site, preparatory work undertaken (Unit still generating/cooling down)
 
Day 2:                  08:00
 
Scaffold underside of preheater: Commence internal set-up of cleaning equipment, cold-side
under; Low-pressure, high-bore flush from above. Additional measures: Gas ductwork above
and below preheater matrix to be protected so as to avoid water/moisture ingress past the
dampers above preheater or into the electrostatic precipitators below air preheaters
 
16:00
 
Commence HP wash of baskets: 26 hour clean envisaged in two passes.Constant monitoring
of drainage and effluent created during the wash including subsequent introduction of Sodium hydroxide solution as and when necessary
 
Day 3:             18:00
 
End wash of baskets; removal of equipment; commence forced-drying of preheater matrix
 
Unit declared available for generation
 
 
 
Case Study 2
 
Dutch Power plant, 600 MW Unit
 
2 x Rothemühle twin-flow Vu 14.5
Primary air element depth 2,200mm (950x2; 300x1)
Secondary air element depth 2650mm (1175x2; 300x1)
 
Cleaning Process before using Hydrotech prior to 2002:
 
Remove entire element layer, top side; transport to ground floor to be washed by conventional hand-held means. In situ clean of middle and cold side elements by conventional hand-held means. Subsequent reinstatement of hot-end elements once satisfactory clean of remaining elements has been carried out by labour-intensive wash.
 
Total duration of shut-down: 3 – 4 weeks
 
Clean Process since 2002 employing the Hydrotech System automated cleaning:
 
Day 1:
           
Arrival on site, preparatory work undertaken (Unit still generating/cooling down)
 
Day 2:
           
Commence internal set-up of cleaning equipment; removal of compensator to allow fixture of rotary joint; scaffold underside of preheater; Additional measures: Gas ductwork above and below preheater matrix to be protected so as to avoid water/moisture ingress past the dampers above preheater or into the electrostatic precipitators below air preheaters
 
Day 3:             08:00
 
Commence HP wash of baskets: 30 hours envisaged in two passes. Constant monitoring of drainage and effluent created during the wash including subsequent introduction of Sodium hydroxide solution as and when necessary
                       
Day 4:             14:00
 
End wash of baskets; removal of equipment; reinstatement of compensator; commence forced-drying of preheater matrix
 
Day 5:            
 
Unit declared available for generation
 
 
 
 
Hydrotech Systems © Hydrotech Systems 2007. All rights reserved.