OIL AND SUSPENDED SOLIDS IN CONDENSATE RETURN

INTRODUCTION

The purity of condensate return and boiler feedwater has always been a concern for operations and maintenance at power utilities. The presence of contaminants (oil or suspended solids, especially iron) in condensate return can greatly increase maintenance costs and significantly decrease boiler efficiency.

APPLICATION

Our main concern in this application is to monitor for oil and suspended solids that contaminate the condensate return. By monitoring the oil and suspended solids in the condensate, power utilities can prevent these contaminants from reaching the boiler. This is a key measurement since the oil and suspended solids can dramatically affect the efficiency of the boilers.

It is also important to maintain very low levels of solids and oil in order to prevent excessive fouling of any condensate polishing filters and thereby reduce downtime.

SOLUTION

The Monitek Acoustic Monitor will continuously check the condensate return and immediately detect the presence of oil and suspended solids.

The sensor will detect even a few ppm of oil or suspended solids.

A high reading from the acoustic monitor would indicate an upset condition in the condensate return line. This could indicate that there was an oil leak in the heat exchanger, turbines, pumps, or other equipment in contact with the condensate stream. The acoustic monitor enables the operators to take immediate corrective action during upset conditions and divert the contaminated condensate away from the condensate tank and boiler.

Oil in the condensate ruins boiler feedwater chemistry. This can lead to corrosion of downstream pipelines and the boiler. The Monitek acoustic sensor can provide immediate and continuous feedback for corrective measures. The monitor can provide an alarm signal that can automatically activate valves to discharge contaminated boiler condensate and prevent it from entering the condensate polishers or boiler.

The acoustic probe will also detect any suspended solids that could foul the treatment system.

By continuously monitoring these parameters, we can reduce the level of downstream contaminants from entering the boiler.

In-line monitoring has been a problem in the past, due to the nature of the process. Conventional optical methods are susceptible to the build up and coating of iron oxides and oil on the sensor windows: this leads to a loss of sensitivity over time. Monitek offers an alternative to traditional optical methods: the acoustic sensor is not affected by any coatings of oil or suspended solids. The acoustic oil in water monitor is easy to use; has an extended calibration; and has no moving parts. Monitek's patented acoustical system allows maintenance free operation in the harshest environments