Prosessivirta

Prosessivirta, or process stream, is a quantity of matter that moves through a process unit or network of units in a chemical, biological, or physical process. It is characterized by a set of state variables that describe its current condition, typically mass flow rate, composition, temperature, pressure, and sometimes phase and enthalpy. A stream may contain multiple chemical species and can exist as a single phase or in multiple phases (gas, liquid, or solid suspensions). Units commonly used include kilograms per second, kilograms per hour, or cubic meters per second.

Describing a process stream requires specifying its properties at a given point in the process. The mass flow rate or mole flow rate indicates how much material moves per unit time; the composition vector specifies the fractions of each component; the energy content is captured by temperature, pressure, and enthalpy. In process modeling and simulation, streams are the links between units and are governed by mass and energy balances. Streams can be split, merged, heated, cooled, or undergo phase changes, and their state is updated as the process evolves.

Applications span chemical, petrochemical, pulp and paper, pharmaceutical, food and beverage, and wastewater treatment industries. They are depicted in process flow diagrams and monitored by instrumentation such as flow meters, thermocouples, and pressure sensors. Modeling tools treat streams as objects with defined properties and use property databases to estimate missing data.

Overall, understanding prosessivirta is fundamental to designing, optimizing, and operating industrial processes, ensuring mass and energy conservation across the process network.