Transcript for:
Water Resources Seminar Insights

all right good afternoon everyone uh my name is Kevin Wagner I'm the director of the Oklahoma Water Resources Center and want to welcome you to our water seminar today uh today we have Dr P bino with us he's an associate professor in chemical engineering and is the Harold hon chair in petroleum engineering and the petroleum program coordinator so Dr bikina and I have worked together for several years um on produced water you know there ways that we can treat it and make it uh uh more usable um not only in the oil field but for for other uses as well and Dr bikina is probably going to say this whenever um he he talks but um people are always amazed when I tell them like the average oil well in the United States produces eight barrels of water per barrel of oil um so a lot of the research has been on other beneficial ways we can use that water that's produced during oil production so it's not Frack water although that can be part of it um it's really broader than that and in like every oil well is producing this water so um he's doing some fantastic work that he's going to be talking about today um and uh he's going to be talking a little bit about some Pro uh some work they're doing related to uh the uh NSF epcore program with the measurement of uh CO2 solubility and brins and hydrocarbons um for CCS you're going to have to tell me what CCs is carbon capture and sequestration there we are carbon capture and sequestration and enhanced oil recovery I know what e o r is so Dr bikina I'll turn it over to you thanks for being here thank you so much Dr KAG uh good afternoon everyone so I hope uh you guys are hearing like the online people so so uh as uh Dr Wagner mentioned I mean the talk is on measurement of CO2 solubility in brins and hydrocarbons for I mentioned only two applications here ccs and E applications but the UR inherently has produce water disposal also you know um all right so here is a brief outline of the talk and um since the talk is related to carbon sequestration enhanced oil recovery and produce water disposal I'm going to briefly uh talk about them you know for the people who are not probably aware of one or more of them and then uh um um mention the objectives of this study and the methodology that we follow and then I'll discuss the results and U conclude it with some key findings that we uh found so uh first let us actually see like what is uh CO2 sequestration so obviously you know we all know that CO2 is a major greenhouse gas right and not because it is very potent compared to other greenhouse gases but because of its uh potency like you know not potency sheer volume compared to the other greenhouse gases carbon dioxide actually is H in terms of uh its volume you know overall effect and hence is uh you know it's a dominating effect so um 3 days ago like the atmospheric CO2 concentrations it's a global average is 421 PPM that was 280 PPM like in 1780s like pre-industrial uh period like 150 plus percentage rise so this is all manmade uh due to the man-made activities uh we know the consequences you know on the environment you know uh and so on don't need to mention them so the sequestration CO2 sequestration is basically a technology that has potency to mitigate this adverse effects of global warming so how it is done basically they capture the carbon dioxide at the source uh like maybe a thermal power plant or um you know other sources like uh you know refineries where they can actually you know get lot of CO2 emissions and then if there is any um purification required they do it and then compress the carbon dioxide from gasius to liquid or super critical State and then inject the carbon dioxide into subsurface formations uh as this schematic shows here you know typically uh the subsurface formations can be depleted oil and gas reservoirs you know so or uh we you know um CO2 can be used for enhanced oil recovery again in depleted oil and gas reservoirs and then we can also inject CO2 into regular um saline aquifers you know so that is purely for uh storage purpose but for other two applications could be you know storage and also for enhanced Royal recovery purpose the fourth applic fourth host site can be a whole bed seams like when we if we can actually inject carbon dioxide into coal beds and due to preferential absorption of carbon dioxide on the coal surface over the methane gas so when we inject carbon dioxide carbon dioxide actually goes and absorbs on the coal surface and dissolves methane like it is enhanced methane production so uh we are actually solving two things here one is um we are getting rid of carbon dioxide and also producing oil under gas you know at the same time so once the carbon carbon dioxide is injected into the subsurface surface formations you know there are like four major trapping mechanisms basically if we inject carbon dioxide for sequestration purpose the objective is you know it should never go back to the atmosphere you know it should be there forever so what makes uh the injected carbon dioxide stays there forever is basically these four uh major trapping mechanisms the first trapping mechanism which is very important at the early years of the uh injection process even during the injection is the structural and statgraphic trapping in general these host sides you know are forest and permeable rock formations um but usually they are accompanied with a cap Rock low permeability Rock On Top of the that high permeability Reservoir so that cap Rock acts as a seal and make sure that you know the injected Co actually stays there so that is structural and statgraphic trapping so then once the injection process is over usually carbon dioxide is in non wetting phase uh to typical these host sites and once the injection is over I mean during the injection the CO2 may be displacing the native fluids already in the reservoir which are typically water and you know uh hydrocarbons but after the or maybe even during the injection itself because C is a non- wetting phase the vetting fluids can might actually come back during that coming back process into the reservoir some of that CO2 will be trapped uh permanently um as a residual CO2 uh due to capillary forces which is a very permanent you know uh very strong uh uh trapping mechanism and then of course um you know CO2 can dissolve in the water braine present in the reservoir and also in the hydrocarbons you know that is that we call it as solubility trapping you know once it dissolves and if those fluids are there along with with them like CO2 is also there and then finally in the long run mineral trapping like the injected CO2 reacts with the fluids and the solids present in the reservoir and then um form minerals carbonate minerals you know they they are the most stable form of sequestration but it takes really long time you know more than a thousand years like tens of thousands of years so earlier years I think structural residual and solubility trapping are important and this talk is about of course uh all three of them but mostly solubility trapping because it is measurement of CO2 solubility in the Aquas and organic fluids but that that solubility will actually in turn affect the residuals trapping and also structural trapping and in the long run even mineral trapping so so coming to the enhanced oil recovery part uh I mean I I presumed at least maybe there may be some non- petroleum background uh audience here and then I'm just briefly going to talk about what you know what is a typical petroleum production system and uh how we produce like uh the oil like the stages of oil recovery so this is a schematic of a typical petroleum production system what you're seeing it here is some major components in the production system the number one component is obviously the oil and gas reserve o without which obviously you the petroleum production system would not you know have any meaning you know because with no Reservoir other components have no purpose and then obviously that's where we have oil and gas and the reservoir if we are talking about saline aquer you know it may not be oil and gas but can just be water so and then we have a well penetrated uh into the subsurface and of course obviously to the reservoir Zone a part of the well and that part of the well we call it as wellbore and uh we have well head you know if you go to any uh oil field what you actually see there in oil well is this part obviously because the the ma majority of the well is actually you know down the down below the sub surface subsurface um so then and of course um um as we can guess um we almost always have oil and gas and water also in the reservoir it does not necessarily be a sell and equiper even in the typical oil and gas Reservoir you know water is always present because before oil and gas actually migrates to that Reservoir it was all water so and hence you know some of that water will always stay there and that water is what we produce you know along with the oil and gas and um so and hence I mean that's a very dirty water we call it as produced water and very high saline sometimes we have you know as nasty as like radioactive elements and um all you know organic waste and all those things um not useful for um drinking purpose for sure and even for agricultural uses also maybe may not be useful as it is unless we actually treat it you know uh and hence um we cannot sell it to anybody it's a cost to the company and we have to you know separate that unwanted water from The Wanted oil and gas and that happens right at the wellhe head and then the gas and the oil uh you know goes on their respective Pathways to either the end user or maybe R and race and if you zoom it into the reservoir part you know as I said this is a you know Reservoir a forest and permeable rock this part both the red green and the blue part and the top portion is the cap rock or the Seal Rock This is what is going to be actually holding the reservoir fluids in place when we inject carbon dioxide into this uh Reservoir formation and this is what is actually causing the structural and Strat graphic trapping you know it's like a seal of of the box so even within the oil Zone I mean gas oil and water are segregated because based on their densities obviously gas is the lightest you know water is the densest so usually we actually drill well into the oil column because it is easy to produce gas because it is lighter lower viscosity right oil is the most important thing so even in the oil Zone we cannot assume that you know it is 100% oil you know uh there would be water as like this is a core sample from that zone and then when you zoom it into that Forest rock you know at a Poe scale you can see those blue Rings they are actually water you know we have water even in the oil column okay so obviously Reservoir is a you know Reservoir is a porest and permeable Rock um filled with maybe partially or like fully hydrocarbons right so it is down below the surface of the Earth as we can rightly guess you know as we go down deep into the you know uh subsurface the pressure and temperature rises right you know um drilling a well into that pressurized environment is like you know putting a pole to your soda can or something you know what happens you know it is under pressure right uh once you drill well and complete it you know that natural pressure energy lets some of that initial oil and gas to produce on its own uh that's the best phase of oil recovery because we are not actually using any external energy source uh to bring the fluids from the subsurface to the surface and then obviously pressure is a finite source of energy and um it would quickly deplete I mean depending upon how we are operating and then by the time the you know that pressure is depleted um to such a level um where it is no longer useful to bring the fluids to the surface we would in the worst case probably we would only produce 5% of the initial uh oil in place so still we have 95% left there and um so then we know the reason why the remaining 95% is still there it is pressure diation so obviously since we know the physics what is happening uh you know anybody would actually attack that right parameter in order to you know get maybe some more oil out that is actually secondary recovery where we inject uh you know a chaper environmentally okay uh fluid to repressurize the reservoir you know through injection Wells and we inject let's say water you know um not very portable water maybe sea water or you know are water produced from the same well or same Reservoir and then it repr pressurizes the reservoir and then sweeps some of the remaining oil towards the production well and it causes some more oil recovery uh with that um you know we may get um additional 10 to 20% of oil so in the worst case lower end if you add like 5% and 10% 8 I mean still we have 85% even after the secondary recovery you know at this time what is happening is at the end of the secondary recovery for example if we are injecting water uh you know uh as a driving fluid are displacing fluid so we are injecting water and we are producing water you know that would not make any sense because you know uh we are not getting any oil out we have to you know stop and see like you know uh what else we can do to get oil more oil so obviously this time it is not the pressure depletion because we can inject as much water right it should be something else and we will discuss quickly what is that something else and then we need to attack those things to get any more oil that that thing we that part of the recovery we call it as tertiary recovery or enhanced oil recovery okay so again let's first discuss you know you know what are the reasons why the secondary recovery is failing after some time and uh so that we can attack on those Rees there are some po scale reasons you know you know you see this schematic here uh the um yellow grains represents uh grains of the forest Matrix like if you have a rock rock has uh grains and pores right the ELO is grains and in the four space the red is oil and you have the blue Rings surrounding to the uh sand greens that represent water I mean already existing in the reservoir of course in it is a two-dimensional diagram and hence the water looks like it is not touching from grain to grain right it looks like a discontinuous phase but actually water is the wetting phase grains are touching each other in 3D and it is a continuous phase always no matter what oil in this schematic is continuous uh first one uh continuous in the sense like you can go from one side of the reservoir to the other side of the reservoir just swimming through by swimming only through oil but once you start injecting water during the secondary recovery you know at the displac of Jone see like what is happening you know at the end of the water flooding uh some some of that oil is getting discontinued you know and trapped in the in that pores once uh you know the size of the trapped oil blob is actually larger than the the the space between these two grains and hence you know that cannot go from here to the other side so once that happens you know if you are injecting water you know water can just bypass and produce on its own without bringing any oil out this is uh capillary trapping you know of oil and uh it is because of the high interfacial tension between the oil and water the oil droplet is like a stiff balloon you know if if we attempt a balloon big balloon to actually push it through a small U you know Keyhole or something it would not come to the other side right the stiffness is what is actually blocking so we need to attack that stiffness to probably to bring to produce some more of the trapped oil that is a core scale mechanism we also have Reservoir scale mechanisms of course these pores are like Micron size I mean micro pores are maybe even in extreme cases narrow I mean Nano Force but Reservoir scales are like miles or you know kilometers scale and uh for example between the injection well and the production well you know if there is a high permeability Zone we call it as a thief Zone you know the injected or the displaced displacing fluid would actually bypass through that zone and uh it would not actually go to the other zones you know even in the swept zone that hyperpermeability zone we know that we have that capillary trapping right in the other zones it's not even it didn't even go so that is one of the reservoir scale mechanisms why there is so much oil left after the secondary recovery and the another reason is a gravity over right for example if you are injecting a lighter fluid like a natural gas or something to recover this heavier oil you know the because of its density uh the gas actually turns to flow at the top of the reservoir it would not come to the bottom and hence that bottom part is unswept likewise if you inject water it would actually tend to flow at the bottom and leaving the top portion unep either way it is you know gravity over right density aspect and then we have viscous fingering what does it mean is if the displacing fluid is uh has less viscosity or less viscous than the oil so it would instead of like a piston uh sweep uh clean FL uh sweep it would actually form finger like structures leaving the you know between the fingers un swep Jones so again these are all Reservoir scale mechanisms these are the reasons why so much oil maybe 85% 85% is like conventional reservoirs when it comes to you know these recent shales and all those things you know probably you know you may not have any primary recovery at all secondary maybe maybe 5% most of it is probably you know or maybe hydraulic fracturing you know all those things that's even a worst case thing okay so we have two dimensional numbers here capillary number and Mobility ratio so these dimensional numbers help us uh what we should do in order to get more oil out of you know out of the reservoir after the secondary recovery you know for example here capillary number is defined as V mu which is um these two parameters are for the displacing fluid velocity of the displacing fluid and the viscosity of the displacing fluid you know these two parameters together represent uh viscous forces and uh over Sigma which is the interfacial tension between the oil and water you know that's what the it is making it stiff the droplet and the Theta is the contact angle reability these two parameters at the denominator are representing uh interfacial forces so this is it is a ratio of viscous to interfacial forces you know so if the interfacial force dominate you know that poor scale trapping is you know uh exists actually because water try to drag the oil droplet along with it due to viscous forces but if the if the you know capillary Force dominates the viscous force it would not move so and hence what we need to do we should increase this capillary number by manipulating one or more of these parameters so that you can expect some more oil obviously the velocity of the injecting fluid uh we cannot really control it because we cannot power wash a reservoir you know if you have a oil Mark or something you know power washing would work actually in the reservoir the velocity is determined by res wire itself basically so we don't really attempt uh you know that parameter but the other three viscosity of the injecting displacing fluid if you in increase the viscosity of the displacing fluid viscous fingering will be addressed right you know uh it would not actually form fingers higher the viscosity of the oil water you know or the displacing fluid that's a positive thing or you can reduce the interfacial tension so that that stiffness would go down and it can easily shape change its shape the fluid and then come from one Poe to the other Poe and and and so on to the uh production Val so likewise Theta wetability you can U manipulate the VAB ility using surfactant um uh so that the capillary number increases and you can expect some more oil out likewise uh Mobility ratio you know I'll quickly talk about it also you know uh these are the effective permeabilities of the displacing and displaced phases the case and the MU is again the viscosity of the displacing and displaced phases so we need to reduce the mobility ratio you know here by either increasing the viscosity of the displacing fluid or decreasing the viscosity of the oil so how we are going to be able to do the uh how we are able to decrease the viscosity of oil Maybe by injecting steam you know if you heat it up it like it right uh how can we actually increase the viscosity of water maybe adding a polymer you know so those are all actually um you know these e techniques once you know what is happening with respect to physics of course you would develop a technology to basically attack those uh that physics right so for example there are you know various types of e uh you know techniques chemical flooding where we can can inject alkaline surfactant and polymer mixer you know uh for enhanced oil recovery what they do is alkaline and surfactant favorably attacks the it reduces the surface tension interfacial tension and favorably changes the contact angle Theta and polymer actually increases the viscosity of the you know displacing fluid you know three effects at the same time you know um you can expect some you know more oil recovery likewise low solidity water flooding I'm going to talk about it later uh in detail and thermal flooding basically to reduce the viscosity of the oil you know which is good IM missible flooding and missible flooding basically you inject a gas and it dissolves in uh the oil and lightens it reduces the viscosity and reduces the interfacial tension you know there are some positive uh effects to favorably change uh the mobility ratio and the capillary number so recently nanof fluids and ionic liquids are also used uh for especially wetability alteration and to some degree interfacial tension reduction also you know um so this is one of our you know work like using Nano fluids for enhanced oil recovery so what you are seeing here is by the way the scale bar the black line is 100 Micron meaning that from one side of this picture to the other side maybe a millimeter so what your seeing here is uh it is a micr fluidic chip it's not a chip per say it's a small portion of the chip you know the chip is 2 cm by 1 cm but what we are seeing is like a like a 1 mm you know across so this is a dead end Poe this is a Poe and uh dead end it only has entrance it does not have the exit so uh we injected oil you know we saturated the chip with oil first and then followed by the objective is like uh we inject the water from the same well we call it as produced water to see if this difficult to produce water can be produced you know so we did water flooding and water was not able to even go in because of course it does not have the exit even when we have the exits you see that at Corners you know outside the four you know oil is stuck you know water can go there but it is not able to recover even Outside Inside it didn't really work so then that water when we replace that water with our proprietary nanofluid see like what happens so the wetability alteration you see like this is this was oil wet you know now it is becoming water wet and you know oil is you know getting out you see that internal inside also it's actually separating uh you know nanoid is separating the oil from the rock you know changing the bability so uh of course I mean that's um like it happened in a day like in a small you know thing sometimes it is like probably happens in 15 minutes day or sometimes it may not even happen depending upon Rock oil and water properties okay so then uh this is um you know latest technology but coming back to our you know objective you know is like using produced water High especially High salinity produced water for enhanced oil recovery purpose unfortunately High sality produced water is not useful for uh you know um enhanced oil recovery you know as you could see here this is again another microfluidics based experiment what you are seeing is like a microfluidic channel of U I think around 500 Micron across and you're not seeing the entire Channel part of it and this is the flow Direction so it's a microfuidic channel made of glass but we transformed it to uh carbonates by some in-house you know geomaterial microfluidic technique and then that I mean that has a carbonat uh surface now and we injected uh High salinity water through that Channel first you know we let it soak and Then followed by a model oil we call it as like um acid number 1.5 oil and to displace the water in a straight Channel any fluid can displace any other fluid you know so uh it did displace uh water was displaced maybe there may be a film of water but mostly oil and not uh you know in this situation like it was all oil you know and then we let it soak what happened is some of the surfactant molecules natural surfactant molecules in the oil actually um made that initially water wet Reservoir into oil wet Reservoir you know overnight and then you know when we tried to inject the same high cinity brain again to displace the oil a Big Blob of oil is stuck to the surface you know ideally it should not stuck but you see that a big blob from one side to the other side you know when we were flowing that fluid it was not even responding you know you I'll play that video but when that high salinity fluid is replaced by a lower salinity fluid you will see like what happens so direction of the flow and uh time and the high city fluid is getting is flowing and stopped and then replaced by a lower fluid I mean it's getting released you can see you know it's wetability is altering you know uh yeah once it loses its contact then it would actually flow um so meaning that lower salinity fluid might actually do better than the high salinity fluid but if we want to reuse the high sality fluid for this purpose what we should do we should dilute it with you know um maybe potable water or something like that which we don't want to do so instead the idea is okay can we use that high sality fluid by itself um by itself um by itself in the sense you know what will happen if we actually carbonate that high salinity Water by adding CO2 into it and inject that carbonated water into the you know Reservoir with the expectation that some enhanced oil recovery along with some of that water or maybe all of that water will be disposed of you know right along with you know some CO2 sequestration so uh one shot three birds basically so very ambitious uh objective we are testing it now and um that objective requires us to know you know how much CO2 like what would be the solubility of CO2 in oils and Waters because you know the properties is for sequestration purpose to quantify how much oil how much CO2 is permanently sequestered in the oil and water phases and as a free pH right for all those quantifications we need to know the solubilities so and of course uh you know I didn't talk about the produce water in depth but uh you know as Dr Wagner mentioned every I mean we have like more than a million actively producing oil and gas wells in the states itself and then on average about almost like 9.2 barrels of water produced with each barrel of oil I mean we should actually technically call those Wells as water wells they oil wells but we still call it as oil well so again 97 barrels of water produces with along with one MMF of gas also natural gas so lot of water and uh to put it in the perspective and in 2021 you know USA generated 20 approximately 26 billion barrels of or trillion barrels probably uh could Beil yeah barrels of produced water very huge quantities and that which is actually 70 times more in volume compared to all other liquid Hazard do was the single most dominating liquid Hazard do W is produced water and that's the reason why we have a separate Wing to tackle it and I think we all probably some of you might have felt the earthquake couple of weeks ago right a week that is because of produced water you know I cannot conclusively say but we know that produced water re injection into class two Wells is one of the reasons for or maybe the reason for induced seismicity which we don't want instead of injecting that into class two injection Wells if you use that water for enhanced oyal recovery the difference between class two injection Wells and the using it for enhanced oil recovery is class two injection Wells is like you are injecting into a dead end the pressure is rising and all the seismicity is getting affected but in the oil for oil recovery you're injecting this fluid and producing another fluid so basically you can manage the pressure there right and then uh yeah as I already mentioned you know to tackle all these um global warming things CO2 sequestration and produce water disposal and enhanced oil recovery we proposed high city carbonated produced water fading and uh and hence we need to know the solubilities of CO2 in Aquas and organic fluids and uh this work is how to measure them in the lab and and model them using maybe any existing methods so we attempted to actually measure the CO2 solubility in you know Aquas brins and also produce water samples and hydrocarbons you know regular hydrocarbons and and a crude oil as well I'm going to show you the uh results and then we also attempted to actually um uh use a state of thermodynamic model to predict the solubility of CO2 in brains and compared it with our experimentalis so this is an experimental setup uh or the procedure we use to measure the solubility of water uh I mean solubility of CO2 uh in brins you know it's a very simple process um you know from the first principles what we were doing was we were actually saturating water or the braine with the CO2 in this pressure cell and then taking a a small sample of that carbonated water through this back pressure regulator into this U you know uh oil uh which is at atmospheric pressure once you actually take that soda and put it into this atmospheric cell you know the water and the gas has to separate because you know and then we measure the weight of the water or the Aquas fluid and the volume of the gas and that's enough to you know know the um saturation or the solubility of CO2 in the uh it's a simple process but when to do it it requires you know a lot of skill and also uh the back pressure regulator that you seeing here is the world's most sense to back pressure regulator you know it requires highend you know instrumentation basically and then the same technique would not be useful to measure the solubility of CO2 in the oils fortunately you know because you know some of the components of the oil lighter components can actually diffuse into the carbon dioxide and then you know you cannot do this weight versus weight volume approach and hence we had to actually build a different system uh the working principle here is basically we have a high press gas glass capillary we take a certain n volume of oil into that capillary tube and then pressurize that with oil I mean uh CO2 what happens is unlike when we pressurize you know brine with CO2 in this case oil swell significantly water doesn't swell you know and the swelling you know the swollen volume is a representation of the solubility how much CO2 you know is dissolved so what all we need is the initial volume and the final volume stabilizer volume from those we can calculate the um swelling factor and from well impact factor to the solubility so and then this is the model that we used and U uh of course we used some machine learning also along with this model and it is a very ENT model and covers a very high uh range of temperatures pressures and serenities practically it covers the entire R uh range we required or more than that so here are the results you know this is a plot between the pressure I mean versus the CO2 solubility what you are seeing here is the solid lines are the experimental data and the uh these um what are those um dotted lines are are um you know the model okay so um this is dzer water and uh next salinity and the highest sality is here uh the trend is basically as the salinity increases you know at every pressure uh the solubility of CO2 in that brain decreases you know and as the pressure increases in all the fluids uh solubility increases as you could see here until 1,000 PSI and above that the increment is like insignificant and that's one Trend and the model and the you know experimental measurements are like decently matched and then the same data here this plot also pretty much X except we also have uh you know experimental data for two produced water samples in this uh plot the we do not know the composition of the produced water we know the TDS and we know the density of the produced water and uh so this produced water sample density is actually between the DI water and one molar NAC brain and the solubility right uh perfectly fell in between you know and hence we thought okay there may be a strong some kind of relationship between the density of the water and how much CO2 it can dissolve and then we plotted uh you know our data that way and we saw strong relationships you know density of the brain versus CO2 solubility at uh different pressures you know each line represents the pressure you know all you know for all the fluids tested you know see the correlation coecients exponentially you know decreasing the solubility with density uh correlation coents are 99 % Plus for all of them so this is uh one of our findings what does it mean is if you know the density of your produced water probably you should be able to you know estimate your the solubility of CO2 in just from the density so I mean without knowing the composition and all those things you know which is a good thing uh then coming back coming to the like the oil solubility work you know as we as I said like we used three different hydrocarbons of different molecular weights hexan to Doan and a crude oil for all of them these blue lines as the pressure increases the solubility is increasing for all of them that's it TR and then as the molecular weight is red increasing the solubility is decreasing you know hexen dissolved more CO2 than doin and we do not know the molecular weight of our crude oil but uh we would guess you know the crude oil has even more heavier components and its molecular weight would be even heavier than the Doan and it has a lower uh you know solubility and the green lines are actually the swelling Factor you know lines you know at low pressures the swelling factors are not that um high but uh especially uh for decan at 700 PSI you know swelling Factor was more than seven what does it mean is 1 ml of decan saturated with CO2 at that pressure swallen seven times you know which is a very good thing for enhanced oil recovery if it swells viscosity reduces if it swells large high enough the two droplets next to each other isolated might even combine again back and flow right good thing so you could see here decan like initial volume and the fin final volume around 30 around 80 so that corresponds to this data point and each brain experiment uh was actually repeated three times each time we got like five data points basically all those points are brain data uh each data point is like 15 replicates here like each data point is three replicates and um so then the conclusion is spelling Factor increases with pressure as you could see here but higher higher pressures and solubility decreases with increase in molecular weight of hydrocarbons and we also tried the same way like if there is any Trend between the density of hydrocarbon versus the CO2 solubility previously it was exponential decline right now it is decline again but it is uh linear decline so for all pressures again you know uh pretty decent correlation questions more than 90% for all of them so again this is a a new finding and uh so these data points are for hexan and uh this these are Dean and this is uh do Dean and crude oil data points all of them are falling on that line so meaning that if you know the density of the crude oil you know you should be able to you know predict the CO2 solubility again like uh we did another um experiment where what happens like U if you also have water along with oil what happens to the swelling factor of the oil would the presence of water uh has any influence on the swelling factor of the oil uh you know we made some modifications to the system so that you know we can have both oil and water in the column and then water doesn't swell it it takes CO2 in but it doesn't swell but oil swells measurement point of view is the same thing like before and then uh when we compare the experiments with the in the presence and absence of water what we found is uh at lower pressures you know for all the you know three systems we tested you know there is no oh by the way Blues are like with in the presence of water and this orange is like in the absence of water you know for uh for three different you know hydrocarbons um up to this all these data points uh there is no significant difference there is no effect of uh you know presence of water but at higher pressure 700 PSI see like you know this is like with water this is without this is with water without water with and without so for even hexine lower molecular weight we have seen some difference here also so the conclusion is that when we have like water along with the oil in it the swelling factors are and and propably solubilities are um smaller uh compared to when we don't have water so here are some quick conclusions you know you know just a recap CO2 solubility in the tested brains and hydrocarbons increases with pressure I it's intuitive uh with pressure solubility should increase but the good thing is that we have a tool to measure the solubilities um you know for unknown systems like uh you know um produced Waters with lot of you know chemistry in it so above 1,000 PSI CO2 solubility the tested brains did not change much as brain density increases CO2 solubility decre decreased exponentially basically and uh CO2 solubility in braine matches well with the model predictions meaning that we can use that model uh you know to predict the CO2 solubility without conducting the experiments the issue is that uh it may not work for produce Waters because it has so many salts you know the model considered only sodium chloride so if you have multiple salts and all those things and hence our experimental system you know you know uh should be used um CO2 solubility decreases with increase in molecular weight of hydrocarbons you know meaning that if you have a heavier oil you know CO2 dissolution may not be that much in it and also and hence it would not swell that much you know so probably CO2 you know SE I mean like e is better for uh you know light Royals which is also a kind of known information uh it's a you know we proved it experimentally as hydrocarbon density increases CO2 solubility decreases linearly so this was exponentially per brain and here linearly Trends were different at high pressure presence of water reduced oil SP in fact and and here is our team and uh myself and Dr H is my um collaborator and Dr uh shopan pradan he's my postar he also did uh PhD with me he was the one who did all these experiments and I mean as I said like mean they are high pressure experiments you know he's dealing with very little volumes you know High all those things like it was like a couple of years work because we were uh waiting for each data point like uh for oil swelling experiments 3 days 4 days because it was all due to uh diffusion only we are not stirring or any doing anything so and then uh the modeling work was done by my PhD student uh Mr R Bach and um so of course without uh the funding sources of this would work would not have been possible and uh the major funding source for this work is like NSF score friend that U you know that is continuous now and we also got some funds from Hamilton syringe company by the way if anybody wants to use it like the monthly fund actually $1,000 $2,000 kind of Grants uh it's very easy actually simple Grant I mean you would immediately know you submit it and then whether they accept it or reject it you can use those funds to buy high pressure syringes or anything or even any other things also outside so uh that was it and uh if you have any questions I will be glad to answer sorry I mean it was like super f train so well thanks for your seminar um I'm always curious about next steps you know what is the next steps maybees number one next steps with your research where you go with that but uh kind of more broadly when do you see this being ready for Prime Time ready for application within the industry yeah yeah I mean this project also involves you know um some microfluidic testing you know basically prepare these brins you know inject it into microfluidic chips you know what what happens some of that oil will be displaced some of the remaining I mean the remaining oil would swell right and uh there will be some uh CO2 dissolved in the water so if you look at uh for example um this picture uh yeah this one so now the volume of oil is the real volume of the oil here because there is no swelling involved right so by by just seeing it you know like what is the volume of it by the way the the depth of the thing is like 20 Micron which I did not mention so but if you inject CO2 or carbonated water the oil swells you know how do you know like you know what is the remaining oil volume that you know volume that you seeing is not the real volume right so you know the swall and volume and uh you can back calculate what should be its original volume and what is the how much CO2 is dissolved in it likewise how much CO2 is dissolved in the water right and that way you know how much produced water is disposed how much uh sequestration happened and what is the true enhanced oil recovery so the reason why we are actually measuring all these things is basically for this application once we use those fluids for enhanced oil recovery it's not like just U using regular water where swelling and all those things would not occur to quantify this uh sequestration produce water disposal and enhanced oil recovery efficiencies you know um we did this work and also we we have actually started working on uh The Next Step also we are actually conducting um microfluidics experiments using High sality carbonated water and um so we are on the way and of course the ultimate thing is like using this in the field yeah so first of all thank you so much for the talk because I kind of I'm I don't have any background in petroleum engineering so I really understand now the complexities of thank what is involved in this it's actually more complex I'm sure but I'm sure but at least I have a sense of thank you yeah um so I have two questions one is more big picture and it's more related to the carbon sequestration and I don't know so I'm asking like you're introducing all the carbon dioxide how does it change the the alkalinity and hardness of the water because you're adding so much that's an issue yeah I mean some of I mean you can probably expect some precipitation precipitations actually you know because you know salts actually might actually precipitate uh it's a very very complex process and um it invol I mean uh somebody should actually consider you know the chemistry of the fluids and rock fluid interactions you know all those things um and then if any precipitation is happening especially near wellbore that might actually block you know for for you know block is for further injection so there there should be a mitigation process or maybe there should be counter measurements and counter measures basically to not to happen you know that all those things obviously yeah a second question is more related to like the the solubility of carbon dioxide in that braine so in the model that you showed it it's nice that your model had very good agreement with your experiments especially for the brins I was just curious why it did not match for di di water is also pretty good match yeah but consistent for me that's opposite because usually for Di you have very good matches and then for real Waters you get the thank you so much for you know this observing and asking and I cannot conclusively say the reason but what um you know my intuition is saying is that uh that experiment I mean the model original model was built like using some experimental data okay okay and um so all the brain data you see that all the brain data is latest data okay obviously the DI water data is 1940s 1930s experimental uncertainities and all those things maybe there if you look at the data of our data you know for example if our uh if this is if the dotted lines are our data and if that is the model prediction and then we can say maybe we did not saturate it fully right consistently our data is I mean we have higher solubility than the model meaning that probably you know the you know experimental data the model is not doing well so that model is based it's not it's it's an empirical model it's not based off a to some extent it is a thermodynamic model but there are some parameters that requires tuning tuning by the experimental data so if the experimental data original data has issues yeah thank you great questions right thank you again for being here it looks likee yeah we have time yeah I'll probably go on a tangent and think about more broader aspect of things so we are talking about carbon sequestration sequestration so we are trying to Caron in the soil or right so but how I approach this is that we have a higher carbon dioxide concentration in the atmosphere now and then for that due to that we have higher temperature so I I see the the positive end of these things which is you know we can plant our uh crops early we can have a longer growing season and carbon dioxide is plant food based sure sure of course so I I can see the other maybe the carbon dioxide isn't so bad but definitely we need to control the rate at which it is ex like increasing sure so we all definitely definitely I mean that's the reason why you know soil sequestration exist in the first place right you know but of course as you would probably agree it's not really the permanent solution right so whereas you know a rightly executed you know CO2 sequestration uh I mean like this um in the forest media probably is more permanent you know it's it's again it's coming into the atmosphere again right soil thing like it's a cyclical thing so but but you know all these things should first of all I mean there is still debate whether this global warming thing is a reality or not I mean like they say some say like it is a cause some say it is an effect you know um you don't know but um you know um it's a science if you know uh uh Global uh what is that Global the CO2 is uh greenhouse gas the greenhouse thing is you know science we know it actually when you have CO2 you know in a a chamber or something like that you know the temperature rises you know anybody can test that so but if that is what is causing uh this uh global warming effect globally or not we don't know but I believe it and um all these things should actually come together soil sequestration and all those things basically tackle that problem um in 2021 [Music] um 2021 and now it is 24 right in the last three years I think U it only increased a few PPM like two or two PPM 3 PPM I mean because my I used my old presentation updated it actually so when I looked at it actually it was 419 now it is 421 so maybe it slowed down actually so yeah uh I don't know I mean we can always check the data it is updated daily even yesterday's data we can actually see thank you thank you so much for attending questions chat all right let thank Dr B again apprciate just real quick um we're going to take a break in March uh and observance a spring break so we won't have a seminar then uh but then we'll be back April 18th with Dr Kieran mangle from B systems and a engineering and then May 16th will be our last the semester we'll have Dr Sher hunt from the USDA a research service so hope to see you then thanks again for being here