Lobitos Water Project 30/11/2016 Initial Plan

Transcription

1 Lobitos Water Project 30/11/2016 Initial Plan Team Manager: Bradley Cunningham Design Coordinator: Umar Harith Bin Mat Zaini Financial Director: Robert Booth Risk Assessor: Dominic Alborz 1

2 TABLE OF CONTENTS PREFACE 3 BUDGET AND BUDGETING 4 MAXIMUM MATERIAL COST NECESSARY PER UNIT: 4 WATER TANKS: 4 ADDITIONAL ESTIMATED COSTS: 4 DESIGN 6 THE MATHEMATICAL PREDICTIONS OF OUR SYSTEM 7 DEW POINT TEMPERATURE (1) 7 ABSOLUTE HUMIDITY (2) 7 AIR FLOW RATE (3) (BASED ON 2 INCH PIPING) 7 SUMMARY 8 SUMMARY 9 2

3 Preface This is a small manifesto of our initial plan. All information contained inside is subject to change throughout the project however, as a team, we have decided on these ideas to be presented for viewing and constructive criticism. Our aim throughout the project has four principles in mind. This is simple, effective, efficient and cost effective. This has been the driving force of our ideas whilst also trying to introduce engineering principles that we have been taught to improve our designs. If you have any questions regarding the information presented or would like to advise of criticise, please do so at lobitoswaterproject@outlook.com. Please also note that a bibliography will not be provided, however, we do have these available on our personal copies and available upon request. 3

4 Budget and Budgeting Maximum material cost necessary per unit: 6m of 4inch/2inch plastic pipe S36/S / inch plastic right-angle joint S m of 2inch plastic pipe (for pump) S Hand Pump estimated cost (dependent on supplier) - 18 Black foil (potential condensing material) per square metre estimated cost Total material cost excluding water tank / depending on which pipe used. Water Tanks: 50L Plastic Tank L Plastic Tank L Plastic Tank These tanks are largely not affordable as they are not marketed for this type of use. Through EWB: 1100L S L S Other tanks would have to be inquired about. A quick phone inquiry to a substantial plastic producing company detailed that a 500L tank would come to about per, and they will be happy to supply sizes between 500 and 7500L. However this is a company in New Zealand and while similar prices could be expected in Lobitos, it should be noted that the supplier we actually end up using may be more expensive. Each unit produces a litre of water every 50 hours; a large number of units would be required to sustain Lobitos. Assuming 50 Units are set up the expected cost would be between 4750 and Additional Estimated Costs: Estimated cost of potential turbine implementation: 15 per unit 4

5 Additional pipe may be required and implementation costs could be fairly high depending on whether they are installed independently or through EWB. In the event of any given part of the system breaking, each part is replaceable, however it is quite likely that will just be through the EWB suppliers. As the tank is the least likely part to suffer damage. We found a series of oil drums that could be used effectively as our water tank. These water tanks are 45 gallon, or approximately 205 litres. A company that specialises in selling these drums produces these and they cost 40 each plus shipping. Shipping is roughly about 15 from the US to the UK. If we assume the shipping costs are similar to Lobitos, although it could be less, this will lead to an overall estimated cost per unit of: 84.87/ depending on which pipe used. 5

6 Design As we all know we will be build an underground condenser. The picture below is a simple condenser to help us understands how simple condenser works. So from this, I reckon we step up the condenser game. We have done some of these before in the initial design: 1. Add a wind-powered turbine to create suction at the inlet and outlet (suck the air out) 2. Some kind of sail on top of inlet to guide the inlet to face the wind direction. 3. A filter inside or at the inlet of the condenser to avoid big debris coming in. 4. We wouldn t have cooling water therefore we use the surrounding (underground) to cool the dew to become water. Hence, plastic material must be void as plastic it s not a good conductor. (cons: I suggest we use metal; however, it may rust. If we use stainless steel it may be expensive) 5. Place a 2.5x2x1 meter manhole for maintenance purposes. 6. Put some sort of wire gauze or any method to increase the surface area in the tank to maximize the amount of water produce from dew. Computer design will be on the way. (software: Solidwork, SketchUp) 6

7 The Mathematical Predictions Of Our System For our system to gauge its production capabilities, we first have to establish what factors we have in the environment surrounding it for water extraction. These factors are moisture within the air, the temperature and the relative humidity. Obvious these values will apply to Lobitos and will be taken as an average. I will also outline these values so that they can be amended to suit as the project progresses if new values are found out (the values will be in red). I will also address the added speed on air intake with the pressure drop in the second part. Each calculation will be under a heading to allow for easy locating. Dew Point Temperature (1) The temperature to which a parcel of air must be cooled to reach its saturation point. t d = t -( (!""!RH) ) - Where td is the dew point temperature in degrees Celsius and! t is the observed air temperature also in degrees Celsius. This would make our td = 24 o C. From this value, we now know that water will condense, as we will be four degrees hotter and this will decrease with our wind tunnel. However, as the system will be underground (which should be cooler), this should allow for a lower number as if the observable temperature is lower, we will have a lower value for td. For example, if we estimate 23 o C underground, our td value will be 13 o C, which will increase the rate of condensation. Absolute Humidity (2) The measurement of the density of water vapour within the air (!".!" T) AH(g/m! ) = e[ (T+243.5) ] RH T Where AH is the absolute humidity, T is the observable temperature in Celsius, RH is the relative humidity in percentage value and e is the base natural logarithm. The value we get here for AH is g/m 3 or 0.022kg/m 3. Air Flow Rate (3) (Based on 2 inch piping) Q a = 60π v(!! )! - Where Qa is the Air Flow rate (m 3 /min), v is the air velocity (m/s) and d is the pipe inner diameter in meters (for our estimation, we will assume the inner diameter is 2 inch), we will also use an average air velocity of 6.6 m/s (assuming this is directed perfectly at our air well inlet). For this, our Air Flow rate would be m 3 /min. We will be planning on using a pressure drop system to increase the speed of the flow rate, however the calculations for this are much more complex and will be discussed if this is followed through. 7

8 Summary Using these values we can make various assumptions about how much water production we can attain. We know that we need the central tank to be at a temperature of 24 degrees approximately which should be attainable through the air flow rate through the piping of m 3 /min and the absolute humidity of 0.022kg/m 3 means that, if we use our Air Flow rate, we can multiply the flow rate by our absolute humidity to acquire our average kg/min of water production which is kg/min or g/min. we can then divide 1000 by this value which would give us 2983 minutes to achieve a litre or 50 hours per system based on the values above. Obviously it is understandable that this is a long time to acquire a litre however, the system is passive and does not require any input from the user so the idea would be to build up the water production first then allow this to be used after a week period so that stores are their to be used. Also, due to the cheap nature of the system, more than one of these stations can be built. Factors do need to be noted within the calculations that have not been taken into account, for example, the temperature will obviously change as this is using 28 o C as a constant temperature whereas this is obviously not the case at night. However, this should still be consistent, as the underground nature of the system will mean that the air will still be cooled as it reaches the central tank. 8

9 Summary Overall we feel that our project is progressing towards meeting our key principles. Obviously we understand that this is not a finished system and will still require more input and work, however we feel that it is important to present our ideas to other teams and the EWB for scrutiny and constructive criticism. Our future plans are to create a computerised design before the end of the year and present this on our blog. We also plan to have a prototype built by February 2017 and then we will have enough time to adjust this if required. Finally we will create an instruction manual then write up our final reports (bear in mind that a lot of steps have been neglected to be mentioned between this.). 9