Operation Experience with On-Line Analysis Equipment

Previous operation experience has shown us that on-line measuring instruments are an essential support to secure adherence to the demanded limit in outflow. They are of enormous importance for the early recognition of anomalies in the biocenosis and, with the help of the recorded course, give an extensive overview of the function in the stimulation. With conscientious and professionally competent care by motivated company staff, the reliability of the operation and the measurement accuracy of the on-line measuring instruments are guaranteed. The expenditure for the purchase and the care of the measuring instruments is calculated into plant business.


a) Time Spent

Time needed for the servicing of the instruments (inspection, duplication tests in the laboratory, calibration, prevention of pollution in the pipelines and preparation of the reagents) was all together 170 hours in the business year 2003, 172 hours in the year 2004, 144 hours in the year 2005, 138 hours in the business year 2006 and 140 hours in the business year 2007.
The time involved per instrument and per week amounted to an average of 33 minutes in the year 2003, 33 minutes in 2004, 28 minutes in 2005, 27 minutes in the year 2006 and 27 minutes in 2007. The time required drops with the years because one becomes always more familiar with the instruments.


b) Reliability of the Operation
The reliability of the operation was established when the downtime of the on-line measuring instruments was recorded. The downtime of all instruments together amounted to 657 hours in 2003, 919 hours in 2004, 760 hours in 2005, 424 hours in 2006 and 775 hours in 2007.
The average downtime per on-line measuring instrument was 109 hours in 2003 (4.45 days per year and instrument) 153 hours in 2004 (6.38 days per year and instrument), 127 hours in 2005 (5.28 days per year and instrument), 71 hours in 2006 (2.94 days per year and instrument) and 129 hours in 2007 (5.38 days per year and instrument). All on-line measuring instruments are very reliable.


c) Accuracy of Measurement

From 1998 to 2007, a total of 1,097 countermeasures for all on-line measuring instruments were carried out int the laboratory.
From these 1,097 countermeasures 934 measures (85%) were within the permissible deviation guaranteed by the manufacturer. With 163 of the 1,097 measurements (15%), the permissible deviations were slightly too large.


d) Operational Costs