Once you’ve got your process design down, your manager will probably want to know something about cost. Aspen Icarus provides a more precise cost estimation than that of the FACT Method, and can be used to price everything from your columns, reactors, and other process equipment (ISBL), to the pavement on your parking lot, and fire hydrants on the road (OSBL). It works in a similar fashion as FACT method, by pro-rating each item and area, but does so in a more detailed manner.
In evaluating your process, you’re going to need to report ISBL and OSBL. ISBL (Inside Battery Limit) facilities are comprised of major purchased equipment costs, and the costs associated with that equipment. OSBL (Outside Battery Limit) facilities include storage tanks, shipping for feedstock and product, cooling water, steam, fire water, instrument air, flare stack, environmental treating, and other facilities (FACT description). Appraising ISBL and OSBL is done through Aspen Icarus Project Evaluator.
Before you begin, the first thing you will need to do is to fix your simulation so that it will import correctly into Icarus. It’s not the simplest thing to remember, but it really should be done to ensure your Aspen file will be properly detailed and analyzed by Icarus.
Fixing an Aspen Simulation to Work in Icarus:
o With your Aspen Simulation open, go to File à Import, and first change the file type to Templates (*.apt). You will need to open a file located under C:/Program Files/Aspen Tech/Aspen Plus 11.1/GUI/ Templates/Simulations/ called Aspen IPE Stream Properties.apt.
o Now go to your Data Browser, open the Components folder, and then open the Specifications subfolder. Click on the Databanks tab, and highlight all of the fields on the right.
o Click the button. Reinitialize and Run. This should allow you to properly import your working Aspen files. Now you will need to send your project to Icarus and map your equipment.
Mapping ISBL:
o Once you have your Aspen Plus file fixed to import, go to File à Send to à Aspen Icarus.
On the left-hand side of the screen, you should see the following tabs:
o Select the first tab, Project Basis View. In the Basis for Capital Costs folder, click on General Specs .
o There is a field labeled Project Type, which indicates what type of a project this is (addition/new). For a plant addition (i.e. for U.O. Labs) change Grass Roots/Clear Field to Inside Plant Addition.
o Now, select the center tab, Process View, and left click your design. Select Map to turn it into an Icarus component. You may also click on to map all items.
o For columns, when you reach the Project Component Map Preview screen, check out the Configuration option box. This lists ten different configurations (use the arrows to scroll up and down – it only looks like it has two options) to choose from. The detailed descriptions are on page 4-30 of the Icarus manual.
o Important Note: Make sure you choose a configuration that does NOT have a split condenser or you will run into problems later on.
o You can also add extra equipment to the blocks you are mapping by selecting New Mapping. Click OK to map.
o To add extra pumps or peripheral equipment, on the left-hand side of the screen, click on the third tab, Project View. Right-click on the main process area, and Add Project Component. The equipment that is of concern to you at this point is listed under Process Equipment.
o Once added, right-click on each item and click Size.
o Enter any required input; this includes known flow rates, pressure head required, etc.
o Click on (or Run à Evaluation Project) and Evaluate All Items.
o Select the area you are dealing with, and on the right side, select List. It should look something like the image to the right.
o Right-click on each item and choose Size to view the sizing information Icarus obtained from Aspen.
o You can also right-click on each item and choose Item Report to view the sizing and cost data. You can also select multiple items at once to view multiple reports. Go ahead and fix anything that doesn’t look right.
o Clicking the Results tab will reveal your overall capital and utilities costs.
Once you’re confident that you have correctly mapped your ISBL components, you can move on to OSBL. A lot of OSBL tends to be project-specific, so be careful with sizing. Most importantly, make sure whatever you tell Icarus, as well as what Icarus tells you, makes sense.
Mapping OSBL:
Icarus is a good tool for estimating the cost of OSBL within your facility. You have probably already used the FACT method to calculate costs of OSBL, and you might find that the numbers are fairly similar. Understand that although Icarus may be more exact with their calculations (FACT only uses percentages of one cost to estimate another), it is also just an estimation based on sizing. For example, it will estimate the size of water facilities, or amount of wiring, based on the area of your plant. Before adding OSBL facilities, note that the following elements are sized with a default value, and will need to be resized:
• Utilities (except for Electricity)
o These are read from the PROJSUM.ICS reports file. Within the Results tab click on the Project Summary tab (it may be hidden if the middle window isn’t expanded enough – its tab should be next to Executive Summary):
• Area Sizing/Pipe lengths:
o Area sizing is needed for infrastructure sizing, and pipe lengths are needed for flare headers, process lines, steam lines, condensate returns, etc.
o Note: To proceed with these sizes, adjust your VISIO diagram to scale for the now known equipment sizes.
o When your scale is under control, you should be able to read area sizes and your pipe rack with a ruler. In Icarus, Areas refer to objects that contain particular types of mapped equipment, not necessarily areas of your plant.
o Piping and wiring lengths are calculated from the center of an Area so be sure that the sizing and type of area specified is accurate.
o The number and size of each type of storage tank should have been calculated previously.
o The wastewater treatment and settling pond sizes are also calculated depending on what your process requires.
• What you do NOT need to add:
o On the left-hand side of the screen, click on the Project Basis tab. In the Basis for Capital Costs folder, click on General Specs . There is a field labeled Project Type, where you can indicate if this is a type of plant addition or a brand-new project. You should choose Grass roots/Clear field, which indicates that this is a new project.
• Icarus automatically adds certain components, which you do not have any control over, so do NOT add these components:
Components Included
Project Type MAIN Substation UNIT Control
Grass roots/Clear field Transformers, Switchgears
MCC*, SW Transformer
Operator Center, Control Center
• Adding OSBL:
o On right side of screen, click the Projects tab and the + sign next to Additional Project Components.
o Double-click on either inch-pound or metric and a window similar to the one shown below should open in the right-hand window:
o Note: Each is considered an “Area” by Icarus. You can either drag the entire area to your project in the left-hand window, or expand the area and drag certain components.
o You might want to create/drag areas for storage, wastewater, main process, and plant area (as big as the whole plant for parking, buildings, roads, etc).
o Once you’ve dragged over the components you need, double-click on them in the left-hand window (Project View) to see their default sizes, and make necessary adjustments to their size or Number of identical units (number you wish to purchase). Check the cost, because some items are too project-specific for IPE to calculate, and you may need to research a cost and add it in.
Some OSBL facilities to consider:
Water
• Raw water treating (Make up for BFW + process water + cooling tower) x 1.1
Clarification and/or silica removal may be required if city water is not the raw water source.
Boiler feed water (BFW comprises all steam demand – non-recovered condensate or process steam) x 1.1. Demineralization required
• De-Aerator All water going to steam generators Electric Power
• Incoming power switch yard Total electric power load
• Motor control centers. All electric motors in facility. One or more for process And one or more for OSBL
• Un-interruptible Power Sufficient for all instrument and shut down systems and emergency lighting (say 5 kW minimum)
• Emergency Generator Say 50 kW minimum Air System (Instrument Air and Yard Air)
• Typically air is available to the consumer at 90 psig. Suggest minimum 300 scfm
• Compressor(s) Usually two at 100%; one motor and one turbine drive
• Air Dryer Usually one sized for 100% + spare
• Air Receiver 5 minutes of capacity going from 90 to 60 psig.
Fuel Gas
• Incoming gas metering station
• Fuel gas supply drum (5 minutes of capacity going from 60 psig to 45 psig with main supply source not flowing)
• Fuel gas collection drum if process makes useable fuel gas
Fire Fighting Facilities
• Central Fire Pumps 200-psig discharge pressure minimum.
1 motor, 1 turbine and 1 diesel minimum)
• Central Fire Water Tank Eight hours at maximum capacity of one fire pump
• Ring Mains Size for 1500 gpm flow or 8 inch diameter minimum
• Hydrants and monitors Sufficient to attack the fire from at least two locations
• Breathing Apparatus
• Fire Truck (Should have some sort of fire fighting truck. May need full size engine)
• Foam inventory
• Fire Station
Aqueous Effluent Treating Plant
• This is very much a function of the plant and the types of aqueous effluents.
• As a minimum, require a collection tank, and aerated bio-digester followed by polishing tank or pond and land farm for sludge disposal. If you can hook up to the municipal sanitary sewer, so much the better, if not then you need a separate sanitary waste treating plant. . Flare System
• Flare line (s)
• Flare Drum (s)
• Flare Stack (s) (minimum height 150 feet)
• Flare drum pump out pumps Roads, Bridges, Fences, Parking Lots
• Should be around 1 – 2 % of total installed cost dependent upon plant size Raw Material Receipt and Product Shipping
• Product Loading System Control Building
• Dispatcher’s Office
These services can be combined in one or more buildings depending upon plant size Spare Parts
Commissioning and Start Up 1% of all equipment and materials Percent of equipment capital cost Insurance Spares Fired Heaters @ 10%
Heat Exchangers @ 4 % Pumps and Compressors @15%
Columns, Vessels, Reactors @ 1%
Fire and Safety Equipment @ 14%
Instruments @ 10%
Electrical @ 13%
Invested Spares 25% of major critical un-spared equipment such as compressors and high pressure pumps
Storage Tanks
The sizing of storage tanks is a function of the amount of material that is likely to flow in or out of them in a given time period.
Feedstock.
If a storage tank is expected to receive one lot of feedstock equivalent to 20 rail cars of 25,000 gallons capacity per car, then the tank must be able to receive at least 500,000 gallons of material. Since it would make no sense to run the tank totally empty or totally full, tanks are specified for a "working capacity. This "working capacity" is then multiplied by say 120% to give the actual size of the tank. So for 500,000 gallons of working capacity we would specify a 600,000-gallon tank for this service.
Continuing this example, the plant would have at least two 600,000-gallon tanks in the feed system. One tank would be receiving feedstock, and the other would be providing feedstock to the process. If the feedstock delivery method is somewhat erratic, or it more or less tank cars might make up a shipment, then there may be need for further tankage.
For added flexibility you might also choose to have three 400,000-gallon tanks rather than two 600,000-gallon tanks.
All incoming feedstock is usually tested for quality assurance purposes, either by random samples or by testing a tank of received product.
If your feedstock is being delivered by pipeline then it is common to run to a tank and then into the process. You would most likely fill the tank one-day, test it the next and release it for processing on the third. This suggests that you should have three tanks each with say 120% of one day's capacity.
Product
Product storage is a function of testing policy and shipment size.
It is industry practice to run a full lab test on a tank before it is released for shipment. Typically samples are taken from the top, middle and bottom of the tank and are tested both individually and as a composite sample. That means that the tank must have no flow in or out from the time the samples are taken. Any product produced in that period must go to another tank(s).
There must be enough tankage for supplying the maximum sized product shipment, plus testing a full tank, plus rundown capacity for product.
In lieu of a witty comment, look at this amusing Dilbert anecdote with the full knowledge that we are nearing the end.