About MFA-Diagrams

What is Material Flow Analysis?
Material Flow Analysis (MFA) is a tool to investigate the flows and stocks of material-based systems.

The objectives of Material Flow Analysis (MFA):
  • Delineate a system of material flows and stocks by well-defined, uniform terms.
  • Reduce the complexity of the system, while providing a basis for sound decision making.
  • Assess the relevant flows and stocks in quantitative terms, thereby applying the balance principle and revealing sensitivities and uncertainties.
  • Present results about flows and stocks of a system in a reproducible, understandable, and transparent way.
  • Use the results as a basis for managing resources, the environment, and wastes.

Methodology of MFA
MFA is a formal graphic language with specific rules and meanings.

There are four fundamental building blocks for a MFA, and two building blocks nested within:

  • Good: Goods are materials within a MFA that are the contents of the flows.
    • Substance: A substance is a concentration of a specific element within a good.
  • Flow / Flux: Flows are directed pathways of goods.  A flow is expressed in [unit]/[time], e.g kg/year, ml/sec, kWh/min. A flux is expressed in [unit]/{[time][area]}, e.g. crop yield per year per hectare, rainfall per year per square meter.
  • Process: Processes can be physical processors, e.g. a factory, an engine, or activities, e.g. running, consumption.
    • Stock: Stock is the accumulation of goods in a process.
  • System: The system is the set of material flows, stocks, and processes within a temporal frame and a spatial or virtual boundary.  Spatial boundaries include a region, a municipal incinerator, a private household, a factory, a farm.  Virtual boundaries can be used to include processes affecting the analysis from outside of a spatial boundary, for example emissions from electricity feeding into the grid.

The building blocks of MFA: Good, Flow, Process, and System.
Source: Paul H. Brunner and Helmut Rechberger, 2004. Practical Handbook of Material Flow Analysis.

To submit a MFA diagram for consideration of posting on this blog, email the image file along with the source and supporting information to mfadiagrams@gmail.com.  This blog is an initiative of Nels Nelson.