Most attemperation that I am familiar with in this setting is to spray water into the steam line in the boiler, before it gets to the turbine. There are temperature limits . How does an attemperator control superheater temperature, if attemperator flow however, if the temperature drops below saturation point (drew point), boiler. babcock & Wilcox power generation group. Plant Service Bulletin. Spray Attemperators for. Industrial Boilers. – Cracks in the thermal liners which have caused.

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What is meant by the droop setting in a steam turbine?


But cascaded reboiler outlet temperature control could be very beneficial too. One supplier of reheater attemperators thought it could mitigate bending and cracking of long masts—generally attributed to bending moments created by the flow of steam and to flow-induced vibration—by shortening the masts to less than half the diameter of pipes they were installed in. Students Click Here Join Us! After separation from the boiler water in the drum, the steam is superheated to improve the thermal efficiency of the boiler-turbine unit.

Less cooling will occur at high steam flow rates. He said that use of a ring-style attemperator might reduce the downstream straight run by the equivalent of a few pipe diameters.

Steam temperature is attekperator controlled by spraying water into the steam between the first and second-stage superheater to cool it down. To present it in a block diagram, it will look similar as in the figure above, except you will have three function generator or f x blocks, one for each of the tuning settings.

Difference between attemperator and desuperheater It probably is.

September 23, at 8: Variable-area probe-style attemperators were a popular choice for low- to medium-flow applications and sometimes still are when orders for plants powered by gas turbines surged in the late s Fig 8. It is is very informative detail.


January 24, at 3: Difference between attemperator and desuperheater My company makes desuperheaters, and there is a difference only in the way you wish it to be.

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Anderson pointed to attemperators as the leading cause of piping failures in combined-cycle plants. Others use a combination of steam and fuel flow that alters spray flow based on the relative difference between fuel and steam flows. This discussion will focus on steam temperature control through attemperation.

Are your measurements and controller outputs ranged exactly the same as they were before the retrofit? A gain scheduler should be implemented to adjust the controller un according to unit load. Difference between attemperator and desuperheater Isn’t this semantics?

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At first, the main and re-heat steam temperatures swinged and it affected MW and steam pressure. Red Flag This Post Please let us know here why this post is inappropriate.

May 8, at 8: Adding to the challenge, steam temperature is affected by boiler load, rate of change of boiler load, air flow rate, the combination of burners in service, and the amount of soot on the boiler tubes.

November 11, at However, you attempwrator likely also require some degree of feedback control to compensate for other variables such as different burners in use, boiler sooting, etc.

Steam Temperature Control | Control Notes

Final desuperheaters are not intended for use after startup. Simple Steam Temperature Control. The manufacturer will specify. This will have a negative impact on the stability of the main steam temperature control loop unless gain scheduling is implemented. This loop measures the desuperheater outlet temperature and manipulates the control valve position to match the desuperheater outlet temperature to its set attempeerator coming from the main steam temperature controller Figure 2.


The disadvantages include the potential for carryover of water into piping and tube bundles harpsand the significant distance of the measured setpoint from the spray-water injection point. The many presentations and technical papers prepared by Anderson and Dooley based on their HRSG assessment program are having a positive impact.

If this is not possible, its integral on attemperator in boiler be blocked under attemperator in boiler one of these conditions: Failure of downstream pressure part—such as pipe fittings, heat-transfer tubes, etc Fig 3.

Ravi, there are several designs for this feedforward of which some seem to work better than others depending on the particular situation, boiler design, fuel type, etc. Difference between attemperator and desuperheater Difference between attemperator and desuperheater Hi All, What are the technical differences between an attemperator and desuperheater.

The time to achieve complete evaporation depends on the total surface area of the water injected and is proportional to the square of the droplet diameter.

The simplest method for controlling steam temperature is by measuring the steam atte,perator at the point it exits the boiler, and changing the spray water valve position to attemprrator deviations from the steam temperature set point Figure 1. What is a condenser in a steam turbine?

Overshoot the desired outlet temperature. Recent Posts F users share best practices with colleagues Special Report: Anderson next explained how attemperation works attdmperator what can go wrong with any desuperheater attempefator, including the following: Why do we use dry steam in a steam turbine instead of saturated steam? This is slightly off topic but still relevant question for Control engineers at a time when Advanced process control schemes attemperator in boiler becoming more prevalent.