OIL & GAS – Refinery automation
PHASE SEPARATION
SensoTech’s LiquiSonic® is an inline analytical system for determining the concentration in liquids directly in the running process without delay. The device is based on meticulous measurement of the absolute sonic velocity and process temperature allowing for the detection of phase transitions.
Phase separation in pipelines
The accurate detection of various phases in a pipeline is necessary for several industries. Often multiple products flow through the same pipe, but every single product is supposed to end in a different location. In applications in which product A is discharged by product B, the intermediate phase is to be separated.
Safety aspects are closely connected in applications with high-risk potential. In particular, the monitoring in multi-fuel pipelines for the petrochemical industry provides not only data about the product quality (incoming goods), but also avoids incorrect filling of storage tanks and thus serious accidents.
In the petrochemical industry, contrasting fuels are conveyed over long distances in just a pipeline. Here the rapid detection of the different products as well as the quality monitoring is focused.
Phase separation in batch processes
In batch processes, the product phases are separated due to the physical and chemical properties of each product.
Application example: biodiesel/glycerol
In the manufacture of biodiesel, glycerol is produced as a by-product. The mixture of the two substances is conveyed in large settling tanks and then has several hours to separate. The LiquiSonic® sensors are usually installed into the outlet of the tank. By the detection of the phase transitions, the valve is activated and the biodiesel and the glycerol are supplied to the processing. The intermediate phase returns to the separation process.
Phase separation in continuous processes
In a continuous process, one or more sensors control the separation of a process stream. In this instance, only the phase-specific value of sonic velocity is monitored and kept constant.
Frequently, the product concentration of the carrier phase varies in the inlet. This quickly shifts the height of the phase boundary. Thus, the carrier phase could be pulled off with the product, which greatly affects the purity. In process the separation is made via one pump in each of the two outlet pipes.
The advantages of the LiquiSonic® measuring and analyzing technology are both the rapid response time of less than 1 s and the connection of up to four sensors to only one LiquiSonic® controller. The controller processes all measuring values and passes the data to the process control system. Depending on the type of vessel and process objectives different installation variants are possible.