Reverse Osmosis Membrane
Calculation on Reverse Osmosis Membrane and draw the mechanical drawing.
Your mass and energy balance will provide information on operating conditions, heat and mass transfer rate required etc. What it does not typically provide is any information on the type/size of the equipment to be employed, materials of construction etc. Thus, the objective here is to make an informed recommendation about the equipment to be used for one particular unit operation. Note that this part of the project may well involve additional calculations beyond those carried out by HYSYS or other Simulators and will certainly involve checking the output of your chosen Process simulation package
- In the case of a membrane system, the number of units, the number of pumps, the arrangement of the cascade, pressures flows etc.
- In the case of activated carbon, the bed volume and dimensions, number of beds, pressure drop etc.
Each group should choose one part of the overall (original) flow sheet - some examples are given below - for this more detailed analysis.
- Reverse Osmosis
- Activated Carbon
It is fully appreciated that these topics differ somewhat in intrinsic difficulty - and this fact will be taken in to account during assessment.
As a guide, your detailed design section should contain sufficient information to enable the equipment to be ordered from a supplier, a standard specification sheet and the preparation of mechanical drawings to build the equipment.
Project Background -
A number of fluorinated chemicals have become concerning pollutants. These chemicals may have entered the environment due to their use in consumer products, as incorrectly disposed of intermediates or from their use in fire-fighting foams at locations such as airports and oil refineries.
Problem Description -
You have been contracted by the owners of multiple airports to capture and treat the run-off from historic fire-fighting training. As a first case you have been asked to design a system for a regional airport, located 30 minutes from a city of 200,000 people that handles 50 plane movements per day. But longer term there may be 20 such plants required.
Fire-fighting training at the airport has resulted in contamination with a small area of highly contaminated groundwater, and a larger area with lower contamination. This contamination has led to nearby residents being unable to use their ground water, and the contamination is now reaching river systems and wetlands that are of recreational and environmental importance.
Summary of a Consultant's report
You a have been given some data summarizing preliminary work done by an Engineering Consultancy. To prevent the plume from moving it is necessary to extract around 3 million m3 of water per year, due to the high rainfall and rapid infiltration of water in the region. It is also likely that over time the concentrations of these compounds will decrease - due to extraction/destruction and infiltration of fresh water - but these compounds will likely desorb from the soil.
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Small Highly Concentrated Plume
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Larger Low Concentration Plume
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Area (km2)
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0.05
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6
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Volume (m3)
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50,000
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6,000,000
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Extraction Required (m3/yr)
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25,000
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3,000,000
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Concentration PFOS in groundwater (mg/L liquid)
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3000
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18.3
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Loading of PFOS on soil (mg/kg solid)
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4.3
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0.24
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Concentration PFOA in groundwater (mg/L liquid)
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100
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0.61
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Loading of PFOA on soil (mg/kg solid)
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0.006
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not detected
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The porosity of the soil is 0.1, its density 2650 kg/m3
There is quite a range in the concentrations specified by environmental authorities around the world for the compounds. The table below gives a summary from a variety of US jurisdictions. It is advisable to
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Country
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Agency
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Guideline PFOA (mg/L)
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Guideline PFOS (mg/L)
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USA
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USEPA
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0.7
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USA
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Delaware Depratment of Resources and Environmental Control
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0.4
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0.2
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USA
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Minnesota Department of Environmental Quality
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0.3
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0.3
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USA
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New Jersey Department of Environmental Protection
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0.04 (may be lowered to 0.014)
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|
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USA
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Vermont Agency of Natural Resources
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0.02
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Attachment:- Assignment Files.rar