Figure 16 is a schematic simplified layout or map of an ammonium production system which has 4 components connected by pipelines. The largest component is a reaction vessel with catalyst and this is located in the centre of the layout. It is shown in section form so that the internal details can be displayed. The top and bottom are sealed with semicircular ends. There is a vertical inlet at the top and a vertical outlet at the bottom. A horizontal but zigzagged pipeline crosses through the vessel which represents a heat exchanger that takes heat out of the gases in the reaction vessel and transfers it into the gases flowing through the pipe. Further down the vessel there is another zigzagged pipeline passing through the reaction vessel which represents another heat exchanger. This heat exchanger takes more heat out of the gases in the reaction vessel and transfers it into a coolant circuit. The details of the coolant circuit are not shown. A compressor is located in the top left-hand corner and is shown as a round object with internal rotating vanes. The vanes are curved to symbolise the ability to increase pressure. There is a horizontal pipe inlet on its left side and a vertical pipe outlet at the bottom. In the top right hand corner of the layout there is a circulation pump. The symbol for the pump is the similar to the compressor but it is smaller with straight vanes. The straight vanes indicate that this pump increases flow but not pressure. There is a vertical inlet pipe at the bottom and a vertical outlet pipe at the top. In the bottom left hand corner there is a separator unit. This is shown as a square with a diagonal line going from the top left corner to the bottom right corner. There is a horizontal inlet pipe on its right side, a vertical outlet pipe on the top and another horizontal outlet pipe on its left side. There are pipelines shown connecting these components. They are depicted using two parallel lines about 1 mm apart and they are either horizontal or vertical. An arrow next to the pipeline indicates the direction of flow which can be up or down, or to the right or to the left.

A horizontal pipeline enters the layout at the top left hand corner and carries nitrogen and hydrogen into the system, flowing to the right. It connects to the left inlet of the compressor. From the bottom outlet of the compressor, a vertical pipe flows down to meet a vertical pipe flowing up from the separator. At the meeting of these pipelines there is a T junction. Imagine the T is on its side with the normally vertical part of the T now horizontal flowing to the right. The two vertical pipelines flow into the T and then flow out of the T to the right. The pipeline continues to the right and connects with the left side inlet of the upper heat exchanger that is in the reaction vessel. Connected to the right side outlet of the heat exchanger is a horizontal pipeline which continues to flow to the right. It then turns left to become vertical and flows up to connect with the bottom inlet of the circulation pump. Connected to the outlet of the circulation pump is vertical pipeline which flows up. It then turns left to become horizontal and flows to the left. It then turns left again to become vertical and flows down. This pipeline then connects to the top inlet of the reaction vessel. Connected to the bottom outlet of the reaction vessel is a vertical pipeline which flows down. It then turns right to become horizontal and flows to the left. This pipeline then connects to the inlet on the right side of the separator unit. A vertical pipeline is connected to the top outlet of the separator unit and carries unreacted nitrogen and hydrogen which flows up to connect to the T junction mentioned before. A horizontal pipeline is connected to the other left outlet of the separator and flows to the left, carrying ammonia out of the system. The pipeline leaves the layout at the bottom left hand corner.

 1.2.4 Ammonia synthesis by bulk production