While all industrial professionals accept that measurement instrumentation applied to operating parameters like pressure, temperature, and level saves money and time and improves operations in industrial plants, sometimes choosing the right instrument to achieve optimum results can be challenging. In a recent presentation, Emerson’s Yutaka Kawaguchi shared how this was the case for a major chemical manufacturer in Japan.
This chemical company is the only plant to produce DMSO (dimethyl sulfoxide) and polysulfide polymer in Japan. The facility uses four partially buried concrete pits and wastewater is discharged from each manufacturing process into the pits. It is then biologically treated and discharged to the public water area. Periodic inspections to check on the safety and soundness of the pits are required by Japanese law.
Emptying the pits to check for abnormalities such as cracks and damage is difficult, so the plant carries out regular “Water Logging” inspections. Any decrease in the water level over the logging period was measured using a level gauge and recorder. Precise handling of the level of liquid in a tank is important in process control, inventory management and custody transfer. In the case for the chemical company, process control was needed to maintain environmental protection and compliance. Using the level gauge and recorder, the procedure for inspecting the four pits was taking two full days and, since certain elements of treatment needed to be stopped, it delayed production.
The chemical manufacturer needed a better instrument.
Because level gauges and recorders had limited performance improvement and cost reduction, the plant installed guided wave radar level devices instead. Based on microwave transmission technology, the guided wave radar is only affected by materials that reflect energy; and temperature variations, dust, pressure, and viscosity do not affect its accuracy – an important factor, especially in challenging applications such as wastewater pits. The devices were very quickly configured, thus saving time, while the accuracy of the guided wave radar was a significant gain over the previous level gauges. Since there was no wiring needed, the installation location could be changed easily if required. Using a digital signal to the DCS improved the repeatability from 5 mm to 2 mm.
The whole inspection time was reduced by 75% and the cost was less than 50% of the original analog instrumentation system, resulting in savings of 1,000k Yen ($9,000). The new system also reduced the number of man-hours needed by inspectors from 22 hours down to 5.5 hours, and minimized the downtime of the wastewater treatment facility, providing savings of 3,000k Yen ($27,000) per year.
All from the simple selection of the right instrument. More information on guided wave radar technology can be found here.
Where could different instrumentation save money in your plant?