Process Graph (P-Graph)
As long as you have technology data inputted in the model, you can access the Process graph. A process graph is a diagram that contains all possible combinations of the technologies and products in the system. This allows you to quickly and easily identify all potential supply chain pathways. P-Graphs consist of raw materials, intermediate products, final products, and technologies.
Raw Materials are unprocessed materials used to make other products (e.g. milk). Intermediate Products are products that can be used as an input to make other goods (e.g. milk produces cheese which can then be used to make pizza. Cheese is an intermediate product). Final Products are products that cannot be further processed into a new product (e.g. pizza). Technologies are any equipment or processes that can transform one product to another (e.g. cheese factory)
In a process diagram, raw materials are depicted as yellow circles, technologies are depicted as gray rectangles, intermediate products are depicted as blue circles, and final products are depicted as green circles.
Dairy Supply Chain Example
The example below shows a p-graph for a milk processing supply chain containing three technologies.
Milk can go through the Ice Cream Factory and be made into ice cream, or it can go through the Cheese Factory and be made into cheese. Ice cream is a final product which can be directly sold to the customer, while the cheese can further be processed by the Pizza Factory to make Pizza. Pizza is a final product that can be sold directly to customers.
Nutrient Pollution Control Example
Technologies do not have to take in only one material and only output one product. There can be many combinations of materials, technologies, and products. An example of a simplified p-graph for the nutrient pollution case study is shown below.
In this example, raw manure can go through solid-liquid separation (SLS) technology or P Release technology. SLS produces two intermediate products, the solid component can be further processed into pellets while the liquid component can go through P release technology to generate phosphorus. The P release technology can take in raw manure, liquid manure, or solid manure and produces Phosphorus.
Waste to Energy Example
The image below shows an example of a P-Graph generated by ADAM. This is the P-graph shown for the Waste to Energy case study. Based on the P-Graph, the Waste to Energy case study only has one type of technology in the system which is an Anaerobic Digestion + Electricity generation technology.
