eq. (9.18)
The income of a project consists of all proceeds from plant operation. Typically, this refers to the revenues of a project. Optionally, for reporting purposes, part of the revenues may be specified as credits. These are not included in reported revenues. Instead, they are used to lower the reported (net) operating cost. The latter is calculated as the difference between the actual operating cost and credits. The two types of income (revenues and credits) are described in detail below.
This consists of all revenues associated with the operation of a plant. These may include all proceeds from:
● the sale of main and side products,
● the processing of influent streams (for waste treatment and disposal plants), and
● the sale of generated electricity.
In SuperPro Designer, the first two revenue sources are determined based on the flow and unit price of streams that are specified as being ‘revenue’ streams. The last revenue source is determined based on the amount and unit price of generated power that is denoted as ‘revenue’. These are described below in detail.
Revenue streams are process input and/or output streams that contribute to the revenues of the project. For most manufacturing processes, revenue streams are typically process output streams (i.e., products). For waste treatment facilities, however, revenue streams could be process input streams that carry waste, if the proceeds from the operation of the plant are based on the amount of waste treated. Each revenue stream can have a unit selling price (if it is an output stream) or a unit processing fee (if it is an input stream) associated with it. This can either be calculated by the program based on the Selling Price of each component present in that stream and the stream’s composition, or it can be set by the user.
In addition, a single revenue stream can be specified as the ‘Main Product/Revenue’ stream. This is the revenue stream which is considered as the main revenue source for the project. This distinction between the main revenue source and other revenue sources is used in the executive summary dialog and in the Economic Evaluation Report (EER). In addition, this stream may be used as reference for specifying a project’s advertising/selling and running royalty expenses. Also, if the main revenue stream is a process output stream (i.e., a product stream), then this stream is also used to account for a product failure rate (see below).
The revenue streams, the main revenue stream, and the calculation options for their unit selling price or processing fee, can be specified through the Stream Classification Dialog; for more details, see Classification of Input and Output Streams. Note that if the selling price or processing fee of a revenue stream is not set by user, the user can specify the selling price of registered pure components through the Pure Component Properties Dialog: Economics Tab; for more details on pure components, see Pure Components.
The revenues associated with a revenue stream are calculated by multiplying the stream’s selling price or processing fee by its revenue rate (i.e., its mass flow rate). The latter is either calculated by the program as part of the simulation or set by user (if it is a process input stream, or the flow demand for that stream is specified by one or more operations that use it). Particularly, if a process output stream is specified as the main revenue stream, the revenue rate of that stream is decreased by a fraction corresponding to the product failure rate. The product failure rate can be specified through the Economic Evaluation Parameters Dialog: Production Level Tab; for more details, see Failed Product Disposal Cost.
Power generation procedures are the only process steps that can contribute to revenues through the sale of electricity; for more details, see Power Generation Procedures.
The revenues associated with the sale of generated power denoted as revenue are calculated by multiplying the fraction of total generated power in the process that is not recycled by its unit selling price:
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eq. (9.18) |
The percentage of recycled power indicates the amount of electricity that is not sold to a grid but is used instead in the process to partially compensate for its power requirements. Thereby, it reduces the operating expenses of the process. The savings associated with recycling of generated power are calculated as:
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The total annual savings that result from recycling of generated power are used to calculate the net annual operating cost of a process; for more details, see Net Annual Operating Cost.
The annual revenues of a project are calculated as the sum of the revenues of all streams and generated power types that are denoted as revenue. In addition, a unit production (or processing) revenue can be calculated by dividing the total annual revenues by the selected flow basis (total flow or component flow) of the stream that is specified as the ‘Unit Reference’ stream through the Rate Reference Flows Dialog: Unit Reference tab. To display this dialog, select menu Tasks \ Rate Reference Flow(s). Depending on whether the selected stream is a process input or output stream, the corresponding unit revenue is denoted as ‘processing’ or ‘production’, respectively; for more details, see Main Product/Revenue Rate Stream.
Here is where you can find relevant figures:
● The total annual revenues and the unit production (or processing) revenue are shown in the Executive Summary Dialog: Summary Tab, the Executive Summary Dialog: Revenues / Credits / Savings Tab, and Sections 1 (Executive Summary) and 10 (Profitability Analysis) of the Economic Evaluation Report (EER).
● The annual revenue rates, unit selling prices and annual revenues of individual streams and generated power types denoted as revenue are listed in the Executive Summary Dialog: Revenues / Credits / Savings Tab and in Section 10 (Profitability Analysis) of the Economic Evaluation Report (EER).
Note that Section 10 (Profitability Analysis) of the Economic Evaluation Report (EER) is only available if the revenues of a project are positive.
These include proceeds from plant operation that are subtracted from the operating cost instead of adding them to the plant’s revenues. Credits may include proceeds from:
● the sale of main and side products,
● the sale of generated electricity.
● the sale of heat as a heat transfer agent.
In SuperPro Designer, the first credit source is determined based on the flow and unit price of streams that are specified as being ‘credit’ streams. The credits associated with a credit stream are calculated by multiplying the stream’s selling price by its mass flow rate. The latter is either calculated by the program as part of the simulation or set by user (if it is a process input stream or if the flow demand for that stream is specified by one or more operations that use it). The classification of streams as credit streams and the calculation options for their unit selling price can be specified through the Stream Classification Dialog; for more details, see Classification of Input and Output Streams. Note that if the selling price of a credit stream is not set by user, the user can specify the selling price of registered pure components through the Pure Component Properties Dialog: Economics Tab; for more details on pure components, see Pure Components.
The second credit source is determined based on the amount and unit price of generated power that is denoted as ‘credit’. Power generation procedures are the only process steps that can contribute to credits through the sale of electricity; for more details, see Power Generation Procedures.
The credits associated with the sale of generated power denoted as credit are calculated by multiplying the fraction of total generated power in the process that is not recycled by its unit selling price:
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eq. (9.20) |
The percentage of recycled power indicates the amount of electricity that is not sold to a grid but is used instead in the process to partially compensate for its power requirements. Thereby, it reduces the operating expenses of the process. The savings associated with recycling of generated power are given by eq. (9.19):
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The total annual savings that result from recycling of generated power are used to calculate the net annual operating cost of a process; for more details, see Net Annual Operating Cost.
Heat transfer agent credits can be created by recovering the heat from a very hot operation in the process. When this heat is matched with a heating agent, under certain temperature conditions, and if the heat exceeds the total demand in this heating agent, then the agent can be credited by the excess duty load times the unit cost of the heating agent (based on an energy basis). For more details, see Energy Recovery.
The annual credits of a project are calculated as the sum of the credits of all streams recovered heat and generated power types that are denoted as credit.
Here is where you can find relevant figures:
● The total annual credits are shown (if these are non-zero) in the Executive Summary Dialog: Summary Tab, the Executive Summary Dialog: Revenues / Credits / Savings Tab, and Sections 1 (Executive Summary) and 10 (Profitability Analysis) of the Economic Evaluation Report (EER).
● The annual credit rates, unit selling prices and annual credits of individual streams and generated power types denoted as credit are listed in the Executive Summary Dialog: Revenues / Credits / Savings Tab and in Section 10 (Profitability Analysis) of the Economic Evaluation Report (EER).
Note that Section 10 (Profitability Analysis) of the Economic Evaluation Report (EER) is only available if the revenues of a project are positive.
Power generation procedures are the only process steps that can contribute to revenues through the sale of electricity. These include:
● Power Generation in a Straight Flow Steam Turbine-Generator Procedure
● Power Generation in an Extraction Steam Turbine-Generator Procedure
● Power Generation in a Gas Expander-Generator Procedure
For each unit procedure, the user specifies the generated power type in the corresponding operation. The amount of generated power is either calculated by the program as part of the simulation (in design mode of equipment) or specified by the user (in rating mode of equipment). For each generated power type included in the process, the user also specifies:
● its unit purchasing price,
● its unit selling price,
● whether it should be treated as revenue or credit,
● whether a percentage of generated power is recycled, and
● the percentage of power that is recycled.
For generated power types that are currently used in a process, the above properties can be viewed or edited through the List of Power Types Currently Generated by the Process dialog. To display the ‘Power Resources Currently Generated’ dialog, do one of the following:
● click Process Options } Resources } Power Types Generated on the Edit menu, or
● right-click on the flowsheet to bring up its context menu and click Resources } Power Types Generated.
To edit the properties of a power type, double-click on the corresponding item on the list; for more details, see Power.
Note that new power types can be created and added to power types databank of the ‘User’ database. To access the ‘Power Types Databank’ dialog, click Power Types on the Databanks menu. To edit the properties of a user-defined power type, switch to the ‘User’ database and double-click the desired item on the list; for more details, see Power Types Databank.
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You may choose to use site power types in a process section. You can store power types with distinct properties behind model database sites and allocate the site with the most appropriate power types to the relevant section(s) within your recipe; for more details, see Sites & Resources Databank. |
Savings to the annual operating cost (AOC) are components that reduce the AOC. These cost-saving components can originate from:
● Recycled power
● Recycled/Recovered energy
If power is generated in the process the user may choose to recycle it, thus reducing the power demands of the process. This reduction will reflect in reduced AOC. For more details see also Generated Power Denoted as Revenue and Generated Power Denoted as Credit.
Energy in the form of heat can be recovered (or recycled) by matching operations requiring cooling (and thus have energy to ‘donate’) with operations requiring heating which currently both utilize actual heating and cooling agents to perform the heating and cooling correspondingly. When such a match is feasible, it will yield double savings since it will reduce the consumption of both heating AND cooling agents simultaneously. For more details see Energy Recovery.
