UTILITY POWER GENERATION
Reliability maintenance is simplified and minimized
Zero-leakage valve features eliminate damage to controls
Metal-seated ball valves are ideal in severe service applications
Biomass power co-generation
Public energy utility providing steam to pulp paper mill and electricity to the power grid
Fuel for boiler is provided by clean wood waste from sawmills and lumber and paper mills; natural gas is used for boiler start-up and auxiliary boiler. All major functions in the plant are controlled by operators with computer support to continuously monitor and report on pressures, temperatures, flow rates, etc.
The attemporator controls steam temperature but the issue was the on/off isolation valves for the attemperator control were leaking and cutting trim on the control valves. The original valves, supplied by the boiler manufacturer, were globe-style valves attached to electric actuators. The plant manager could not get adequate service support from any of the original equipment makers. Consequently, there was no consistent control of the steam generated by the boiler operation.
Novaspect engineers recommended the following control configuration: three 2-inch EVS 1500 pound, 1.5-inch bore F22 body socket weld metal seated ball valves attached to Field Q QD600 actuators with an Asco solenoid and a Topworx limit switch for each unit.
Metal-seated ball valves have proven to be the valves of choice in severe service applications where critical shut-off or isolation of flow must be achieved due to safety, environmental, or maintenance concerns. The installed valve assemblies are fitted with zero-leakage features, thereby eliminating damage to controls from leaks.
The steam control installation before replacement of valves and controls. Original equipment had issues with leakage and damage to controls that impacted maintenance reliability. To make matters worse, there was no service support from the component manufacturers.
The plant manager could not get any support from the original equipment manufacturers. Because of the success Novaspect has had on other projects in the plant, he called us.
The plant manager is pleased with how the Novaspect solution has made valve maintenance much easier. The technicians who maintain the equipment on-site prefer the double-acting pneumatic actuator to the inferior original electric actuator performance. In addition, the local support of sales and service reps is convenient and helpful for training and troubleshooting.