reverse osmosis – NOAA Teacher at Sea Blog

July 6, 2022July 6, 2022

Oktay Ince: Reporting from the Ship Engine Room, June 28, 2022

NOAA Teacher At Sea

Oktay Ince

Aboard NOAA Ship Thomas Jefferson

June 20- July 1, 2022

Mission: Hydrographic Survey

Geographic Area of Cruise: Lake Erie

Date: Tuesday, June 28, 2022

Latitude: 41° 36′ 5 N

Longitude: 81° 30.7′ W

Altitude: 138 m

Weather Data from Bridge

Wind Speed: 1.6 kts

Surface Water Temperature: 22.2 °C

Air Temperature (Dry Bulb Temperature): 18.2 °C

Wet Bulb Temperature: 12.7 °C

Relative Humidity: 55 %

Barometric Pressure: 10.24 in

Science blog

Today, I am going to share some science and technology information from the engineering department. The engine room is located on the two decks below the main deck. The engineers have many tasks and responsibilities on the ship. I am going to share some of the main ones.

The first responsibility is to make sure the ship engine is working properly. Engineers work around the clock to make sure that in the case of an emergency, they can act quickly. As you may imagine, the ship has a huge engine with many cylinders. I was very lucky to see the engine before and after it was working. When we anchored our ship near the Rocky River, we stopped the engine. The ship’s electric power is powered by three diesel generators. This powers various systems in the ship such as AC, heating, computers, refrigerators etc.

When we were ready to get underway from anchorage for our next journey on Lake Erie, I thought it was a good idea to observe the engineering department and see how they start and operate the engine. Anyway, I went down there about 20 minutes before our departure. Engineers were busy as bees around the machines touching, clicking, opening/closing valves. There was a constant movement. They all know what to do, including me. My job is to watch how the ship engine operates. I was roaming around to see what would be the best place for me to videotape the moment when they start the engine. Luckily, I found one, and “loudly” waited there. Oh, I forgot to mention. Before you enter this place, you have to have hearing protection. I put my ear plugs in and on top I put on ear muffs. I was told the noise was going to be so loud. Once they checked all the parts, it was time to start the engine. All the pistons started to move, and it reminded me of the sound of my mom’s old sewing machine, where there was constant ticking, clicking sounds. It was fascinating to witness that moment.

Starting the ship’s engine

The ship engine is fully operational

Oktay and an engineer pore over notebooks at a table in the engine room — Learning about engineering concepts

four computer monitors in a line, above a control panel — Learning about engineering concepts

Hear this! Every important part in the ship has a back up. Some of them even have third, or fourth back up. For example, when I went to the bridge to learn about how they control the ship up there, the first thing they told me was that everything has a back up. If one screen shows a map, here is the same map on a different screen. So the engine also has a back up, an auxiliary engine, in the case of an emergency it would quickly kick in. However, the auxiliary engine does not have the same power as the main engine. Its role is to keep the ship out of danger, until the main engine issue is resolved, or the ship can pull into port. There was also a steering room down in the engine room in case the deck loses its steering control, they can manually steer the ship down below. Isn’t that cool! For that purpose, there is always an engineer on watch who monitors the steering gear around the clock. Remember, the ship works 24 hours.

Besides engines, the ship has a water treatment system down in the engine room. To be honest, this was the moment where my excitement made its zenith point. You would understand this when you read what I am about to say on this. The water treatment system consists of many tubes which contain membranes to filter the water, desalinate it, and make it ready to drink. The system uses the concept of reverse osmosis (RO) to make drinkable water out of any water systems, even the ocean. However, I must note that even though the technology allows you to make the water, engineers make decisions whether to make the water based on several factors. First, it is preferred to be at least 12 nautical miles offshore in open water. This is because the water is less likely to have pollutants that could clog the filters, which would quickly lead to other issues for engineers to deal with. Deep water is also preferable for similar reasons; sediment, mud, and sand that can be churned up in shallow waters is another way for the filters to be clogged. In the case of Lake Erie, engineers decided to NOT make water because we are working relatively close to shore, and would not be an efficient use of resources. This is because the ship fills all its potable water tanks (~50,000 gallons!) in port using municipal water from the City, which is enough to supply the ship for several weeks. The ship uses ~1,500 gallons of freshwater a day! But remember, that is for a 30 person crew – eating/drinking, showering, cleaning, etc. Long story short, we have sufficient water in the tanks for the duration of our mission. Therefore, there is no need to make more water.

large pipes in an array; tubing; wires — Reverse Osmosis (RO) System

Okay, let’s go back to the concept of desalination by using reverse osmosis. It sounds complicated, right? It is quite simple in principle. To be honest, even myself, who trained in biology both during my bachelors and graduate school, thought that so many people in the world can’t use ocean/sea water to solve the water crisis because the technology is very “expensive” and that is not an option. On the contrary, it is a very simple science concept and it is relatively cheap when you think of the product and the benefits it has. However, why is it still not accessible to everyone in the world? I guess the question will stick in my mind from now on.

Let’s get back to the science concept of osmosis and reverse osmosis. In osmosis, you have a semi-permeable membrane where water moves freely without energy input to the system until the two sides of the membrane have equal number of water molecules. The osmotic pressure to the membrane is equal in both sides due to having the same amount of water molecules on both sides of the membrane. Cells in our body are semi-permeable and water can go in and out of the cell based on the concentration of solutes in both sides of the membrane. You can see the concept of osmosis in every biological system. We have even applied the concept of osmosis since ancient times to preserve foods by dehydration with salt or sugar such as jams, pickles, pastrami and so on. The microorganisms that make food go bad can’t survive without the presence of water. That’s why honey is the only natural product that never goes bad due to its high concentration of substances.

In reverse osmosis, the movement involves water molecules passing through a higher substance concentration (sea water) to a lower substance concentration. As you can see it is the opposite of osmosis. Water should move the other way around. How do we achieve that? When we apply a pressure high enough to the point where it is higher than the osmotic pressure to the saline water, it causes fresh water to flow through the membrane while holding back the salt. The higher the applied pressure above the osmotic pressure, the higher the rate of fresh water transports across the membrane. Here you have freshwater on the other side of the membrane. Pure and simple. Based on the membrane you use in the system, it also traps all the other pollutants as well. Mind blowing! This is how the ship makes its own freshwater.

So far, we talked about engines and the RO system of the ship. We also have generators down there. They are the ones that generate electricity by using fuel. The ship generally runs on one generator at a time, but may require two during some operations. However, the ship has three generators on board in case others fail.

I guess I’ll leave it here and let you learn more about the science and technology of ship engines and RO systems on your own!

Personal Log

As educators, we often fail to connect our discipline to other disciplines. We usually don’t understand how one concept has many other applications. If being a Teacher at Sea on Thomas Jefferson taught me one thing, it’s that science concepts intervene with other disciplines. If students don’t see these connections, or how the concepts they learned apply to different circumstances, then I believe they fail to see the bigger picture. As a result, “true” learning will never be achieved.

I was a scientist by training before I became an educator, and of course I know what osmosis is in biological systems. However, I must confess that I did not see the applications of osmosis this far, not even during my graduate studies. There has not been a single educator who showed me the concept of osmosis in this perspective. I don’t blame them. They probably haven’t had a chance to learn that way too. All I remember is the “U” shaped diagram with a semi-permeable membrane in the middle, and each side having different concentrated solutions, which shows how the water moves freely. And then they explained how once it reached equilibrium, both sides of the membrane had equal concentration. From there, they talked about different solution types, energy requirements of moving molecules from one side to another, etc. I guess you all remember this from your biology or related courses.

From this teaching, did you ever think about how this science concept is used in different applications? Like in this case, reverse osmosis to make freshwater from seawater. If you did, lucky you! You are one of those lucky ones- I didn’t have that opportunity. At least, I did not think about it at the moment. All I worried about was learning the concept and moving on. I guess my teachers at that time had the same “vision” as me. Teach the concept, test it with multiple choice questions and then move on thinking that students learned. When those students come across the same concept in different settings, they mostly fail. The justification of the educator would be like, “I don’t know why they failed. I taught them the materials and had great scores. They must have had a bad day during the testing.” Yeah! Yeah! Yeah! I know those.

Sorry for my long thoughts about our educational system. We really should, at least, teach science concepts to our classroom through its real world application. Only then, would they appreciate the power of the science concept they are learning, which could open a lot more creative ideas on their own, leading to innovation. These were thoughts that sparked my mind thanks to reverse osmosis (RO) system technology on the ship.

Another important thing that came to mind while I was down in the engine room was the importance of teamwork, and how important it is to always have a back up. We all know the importance of teamwork, and how the members of each team are equally important. But when it comes to teaching teamwork to the kids who have not experienced real teamwork, do they really understand its importance? If we want our students to work as a team in our classrooms, we need to design our lessons in a way that if one of the team members fails to complete a task assigned to them, the whole task fails along with it. Once they know this, I think the true understanding of teamwork will prevail to the students.

These were the thoughts that I have been contemplating while witnessing all the cool things I saw in the engine room. Who knows how students would be impacted if they saw these things?

Did you know?

Waves in Lake Erie are mainly caused by winds because of its shallow nature. If those waves move away from their generation zone, they become more regular and then are referred to as swells.

June 6, 2019June 6, 2019

Jill Bartolotta: The Ins and Outs of Going, May 31, 2019

NOAA Teacher at Sea

Jill Bartolotta

Aboard NOAA Ship Okeanos Explorer

May 30 – June 13, 2019

Mission: Mapping/Exploring the U.S. Southeastern Continental Margin and Blake Plateau

Geographic Area of Cruise: U.S. Southeastern Continental Margin, Blake Plateau

Date: May 31, 2019

Weather Data:

Latitude: 28°29.0’ N

Longitude: 079°34.1’ W

Wave Height: 1-2 feet

Wind Speed: 15 knots

Wind Direction: 155

Visibility: 10 nautical miles

Air Temperature: 27.6 °C

Barometric Pressure: 1013.7

Sky: Few

Science and Technology Log

Today and tomorrow I am learning all about the who and how of making the ship go. Ric Gabona, the Acting Chief Marine Engineer, has been teaching me all about the mechanics of powering the ship, managing waste, and providing clean drinking water. Today I will focus on two aspects of making it possible to live on a ship for weeks on end. First, I will teach you about waste management. Second, I will explain how freshwater is made to support cooking, drinking, cleaning, and bathing needs. In conjunction, all of these systems contribute to our comfort on board but also our safety.

Wastewater Management

Waste on board has many forms and it all must be handled in some way or it can lead to some pretty stinky situations. The main forms of waste I will focus on include human waste and the waste that goes down the drains. The waste is broken down into two categories. Black water and gray water. Gray water is any water that goes down the drain as a result of us washing dishes, our hands, or ourselves. Gray water is allowed to be discharged once we are 3 miles from shore. The water does not need to be treated and can be let off the ship through the discharge valve. Black water is water that is contaminated with our sewage. It can be discharged when we are 12 miles from shore. Black water goes into a machine through a macerator pump and it gets hit with electricity breaking the solid materials into smaller particles that can be discharged into the ocean.

Discharge of gray or black water has its limitations. These discharge locations follow strict rules set in the Code of Federal Regulations (CFR) and by the International Convention for the Prevention of Pollution from Ships (MARPOL). The CFR are set by the federal government and the regulations tell you where (how far from shore) you are allowed to discharge both gray and black water. However, sometimes Okeanos Explorer is in areas where black water cannot be discharged so the black water must be turned into gray water. At this point, once the black water has been mashed it will pass through a chlorine filter that will treat any contamination and then the waste can be discharged. However, there are places where nothing can be discharged such as Papahānaumokuākea Marine National Monument in Hawai’i. When in these no discharge areas the ship will store the gray and black water and then discharge when regulated to do so.

It is important to follow these regulations because as Ric says, “We are ocean stewards.” It is important that ships such as Okeanos Explorer be able to explore the ocean while making the smallest environmental impact as possible. The engineers and other ship and science mission personnel are dedicated to reducing our impact as much as possible when out at sea.

Making Water

Water makes up 60% of the human body and is vital for life. However, 71% of the water on earth is saltwater, not able to be taken up by humans, making it challenging to access freshwater unless you live near an inland freshwater system like where I come from up in Ohio along the Great Lakes. While out at sea, we have no access to freshwater and we cannot store freshwater from land on the ship so we must make it. On Okeanos Explorer freshwater is made using two types of systems, reverse osmosis and desalination. Reverse osmosis is used by seabirds to turn saltwater into freshwater. Saltwater passes through a semipermeable membrane allowing the smaller water particles to pass through while leaving the larger salt particles and other impurities behind. If you are seabird, you excrete this salt by spitting it out the salt glands at the top part of your bill or if you are a ship out through a separate pipe as brine, a yellow colored super salty liquid. The other method on the ship used to make water is desalination. Desalination is the process of boiling salt water, trapping the water that evaporates (freshwater), and then discharging the salty water left behind. The engineers could use a separate boiling system to heat the salt water however they have a much more inventive and practical way of heating the water. But before I can let you know of their ingenious solution we must learn how the engines run. Oops! Sorry, I need to go. Need to switch my laundry. So sorry. We will explore ship movement and the engines in the next blog. Stay tuned…

flow meters for potable water and brine — Can you see the yellow colored brine and the clear colored potable water?

Filtered water station on the ship. Look familiar? You may have one like this in your school.

Personal Log

I really enjoyed learning all about the mechanics of operating the ship. It takes lots of very skilled people to make the equipment work and I love the ingenuity of the machines and those who run them. Space is limited on a ship and I am just fascinated by how they deal with the challenges of managing waste and making freshwater 50 plus nautical miles from coast for up to 49 people. Today was a great learning day for me. I do not know much about engines, wastewater treatment, and water purification systems so I really learned a lot today. I now have one more puzzle piece of ship operations under my belt with many more to go.

Aside from my lesson in thermodynamics, combustion, chemistry, physics, and other sciences that I have not touched since college, I learned about the safety operations on the vessel. Today we practiced a fire drill and an abandon ship drill. We learned where we need to go on the ship should one of these events ever occur and which safety gear is needed. I donned my immersion suit and PFD (Personal Flotation Device) to make sure they fit and all the pieces/parts work. Being in the ocean would be a bad time to realize something isn’t right. Donning the safety suit was a funny situation for all movement is super restricted and you feel like a beached whale trying to perform Swan Lake on point shoes.

Jill in immersion suit — Me in my immersion suit, fondly known as the gumby suit.

However, with some help from my friends we were all able to get suited up in case an emergency should arise.

Tonight I look forward to another sunset at sea, some yoga on the deck, and seeing a spectacular star display.

Did You Know?

Eating an apple a day while at sea can keep seasickness at bay.

Ship Words

Different terms are used to describe items, locations, or parts of the ship. As I learn new words I would like to share my new vocabulary with all of you. If there is a ship term you want to know more about let me know and I will find out!

Galley: Kitchen

Mess Deck: Space that crew eat aboard ship

Fantail: Rear deck of a ship

Pipe: Announcement on the ship via a PA system

Muster: Process of accounting for a group of people. Used in safety drills on a ship such as a fire or abandon ship drills.

Stateroom: Sleeping quarters on the ship

Abeam: On the beam, a relative bearing at right angles to the ship’s keel

Bearing: The horizontal direction of a line of sight between two objects

Animals Seen Today

1 flying fish

Whales (Too far away to tell what they were but we saw their spouts!)

June 23, 2015August 21, 2021

Sandra Camp, Beam Me Up, JJ!, June 22, 2015

NOAA Teacher at Sea
Sandra Camp
Aboard NOAA Ship Hi’ialakai
June 14 – 24, 2015

Mission: Main Hawaiian Islands Reef Fish Survey
Geographical area of cruise: Hawaiian Islands, North Pacific Ocean
Date: June 22, 2015

Weather Data: partly cloudy, visibility > 7 NM (nautical miles), winds ENE 10-15 KT (knots), seas SE 3-5 ft., air temperature 88° F, water temperature 79° F

Science and Technology Log

Chief Engineer James Johnson, “JJ,” in his domain on the engineering deck

Science is not just happening with the Coral Reef Ecosystem Division’s fish survey aboard the Hi’ialakai, science is happening all the time all over the ship. Today I was fortunate enough to go on a tour of the engineering deck with the ship’s Chief Engineer, James Johnson (“JJ”), to take a look at some of the technology and machinery that keep this ship running. Engineering is so huge, it requires its very own deck. On this deck, there is the propulsion room, the shaft alley, and the control room, just to name a few. Besides the engines and rudders and propulsion equipment that keep the ship running literally, there are so many things that have to function properly on a daily basis, because life on board depends on them. We need fresh water for showers, scientist gear cleaning stations, drinking, cleaning, and cooking. We have air conditioning so the temperature is comfortable on board. The galley needs refrigeration to keep food fresh and power for cooking. There must be an efficient system for disposing of waste. There are washing machines and electric gym equipment, and a host of other things that all need to work on the ship. All of that takes place in the Chief Engineer’s domain.

Steering Controls — In a worst-case-scenario, the ship could be steered from engineering.

One of the interesting things I learned on my tour is that the ship uses about 2,000 gallons of fresh water on a daily basis. After 10 days at sea, we have used about 20,000 gallons of fresh water all together. Where does all that fresh water come from? The ocean! The engineering deck contains a machine called the Watermaker. It uses reverse osmosis to desalinate seawater. This device is capable of producing 3,000 gallons of fresh water a day. It is pretty amazing.

There is so much going on in the engineering deck, I found it a bit overwhelming. I am amazed that one person (with a small army of helpers) could know how to run all of that different equipment, and to know how to fix it all if anything goes wrong. I know JJ has had many years to develop his skills, but I am still very impressed.

Interview with the Captain!

I have been very impressed with the professional and efficient way the Hi’ialakai is run, particularly with its attention to safety. This is all to the credit of CDR Daniel M. Simon, the commanding officer of the ship. He was kind enough to take some time out of his busy schedule to sit down with me and talk about what it’s like to be a NOAA Corps officer and the captain of a NOAA ship.

What are your primary responsibilities?

Overseeing the overall safety of the ship and the completion of the mission. I ensure that navigation routes are safe and take care of any issues driving the ship. I work with the chief scientists to make sure the mission is completed as safely as possible.

What do you love most about your job?

There are two things I love most: First, the adventure of it all. We are getting to see parts of Hawaii most people never get to see. Earlier this year, we were in Samoa, and last year we had a mission in the Marianas. Second, organizing and managing everything and seeing it all come to fruition.

What kind of education do you need to have this job?

In order to become a NOAA Corps officer, you need a four-year college degree in math, science, or engineering. After that, you can apply to be an officer. I have so far worked for 14 years as a NOAA Corps officer. I spent time on research vessels as an ensign and as an executive officer. I worked in many different capacities in those positions and gained experience that was valuable to becoming commanding officer of the Hi’ialakai, the position they have assigned me to here. I did not always want to be the captain of a ship. I did not have any experience with the ocean before applying to NOAA Corps; it was all new to me. Even though my background was in science, it had nothing to do with a ship. I looked at it as a treasure trove of new information to learn. NOAA sent me to dive school, and I had never even snorkeled before!

Do you have any advice for young people interested in your line of work?

Get the education. College degrees open a lot of doors. Have an open mind, be open to learning new things, and be willing to try new things. I still learn new things every day. Love learning because it never ends. Recruiters are looking for these things: open-mindedness, love of learning, and the ability to handle yourself.

Personal Log

Today, I got to go up to the bridge and see what the command center of the ship is like. Besides a nice view, they have a lot of special equipment up there that helps them navigate the ship and keep an eye on the small boat operations taking place on a daily basis. I learned how to plot the ship’s location on a nautical chart using both GPS coordinates and visual fixed-point references. They even let me steer the ship.

Visual Reference — Taking a visual fixed-point reference

Plotting the ship’s location on a chart using GPS coordinates

My time aboard the Hi’ialakai is quickly drawing to a close. I am very grateful for the opportunity to come aboard and be part of this mission. I learned so many new things every single day, that I have enough material for at least 20 more blogs! Unfortunately, I will be unable to write them. I would like to thank the Coral Reef Ecosystem Division and the rest of the science team conducting the mission for letting me learn about and share their very important research. I would also like to thank the crew and the officers for being friendly and making my short stay here a pleasant one, and particularly the captain for keeping us all safe.

Aloha Honolulu — A last view of the Oahu coastline as our ship pulls in to Pear Harbor

July 7, 2013August 11, 2021

Sarah Boehm: The Dead Zone, July 5, 2013

NOAA Teacher at Sea
Sarah Boehm
Aboard NOAA Ship Oregon II
June 23 – July 7, 2013

Mission: Summer Groundfish Survey
Geographic area of cruise: Gulf of Mexico
Date: July 5, 2013

Weather at 19:13
Air temperature: 26°C (79°F)
Barometer: 1017mb
Humidity: 93%
Wind direction: 135°
Wind speed: 18 knots
Water temp: 27°C
Latitude : 28° 44’ N
Longitude: 85° 32’ W

Science and Technology Log

Mr. Cummiskey, the other science teacher at CDCPS, asked if we saw an influence from farming along the Mississippi River in the Gulf ecosystem. At first it seems crazy that something happening over a thousand miles away can have an impact on an ecosystem as vast as the Gulf of Mexico, but it really is happening and part of our research is to monitor the effects. The first clue I had that something was changing was the color of the water. In the deep waters off Texas the water was a beautiful clear blue. As we got closer to the Mississippi delta the sea water turned a murky brown–a mix of mud brought down by the river and the phytoplankton that was thriving in the nutrient dense waters. Just like eating too much food is bad for people’s health, too many nutrients is actually bad for an ecosystem.

The CTD instrument. The bottles on the top collect water and the instruments on the bottom take measurements.

Each time we get to a sampling station we start by taking measurements of the water quality with the CTD (conductivity temperature and depth). From the bridge the officers control the ship to keep it in one place. Then the deck crew uses a winch and pulley system to move the heavy CTD equipment overboard and down into the water almost to the sea floor. All the way down and back up the machine is taking dozens of readings a second that are transmitted back to a computer in the dry lab.

The CTD records the depth, water temperature, the salinity (how salty the water is), and the dissolved oxygen. We are most concerned with the oxygen level because it greatly impacts the organisms living in the water. Fish and marine invertebrates breathe oxygen molecules that are mixed in with the water. Without enough dissolved oxygen in the water they will suffocate and die. Healthy levels in the Gulf of Mexico are 4 to 6 milligrams of O₂ per liter of water. If there is less than 2 mg/L it is considered hypoxic, meaning there is not enough oxygen. This map uses the data we have collected this cruise to show dissolved oxygen levels in the bottom waters of the Gulf. The green and yellow colors shows the healthy areas, the orange areas are hypoxic.

Click on the map for a larger version. The map is updated as new data comes in.

See those orange areas in close to the coast of Louisiana? That is known as the Dead Zone. Runoff of fertilizer and other nutrient sources wash down rivers and out to sea where they contribute to algae blooms. When the algae dies it sinks and is decomposed, a process that uses up a lot of oxygen. Check out this video to learn more. All my 6^th graders should notice similarities between this situation and the virtual pond we worked with this spring.

Hypoxia video

Not only do the oxygen levels change, but the composition of the fish trawls changed dramatically too. At station #144 we had an oxygen reading of 3 mg/L and an average sized trawl (26 kg) with a variety of species. At station #146 we had an oxygen reading of 1 mg/L (which is hypoxic) but pulled up a huge net of fish that filled 18 buckets. The total weight was 340 kg, but over 300 kg was just two species – croaker and butterfish. We were surprised by this catch and so did another oxygen reading and found while our nets started in hypoxic waters, during the 30 minute trawl we moved into better water with 3 mg/L of oxygen . At station #147 we had a very low oxygen reading of only 0.2 mg/L. Our trawl only brought up 1.7 kg, most of which were jellies and crabs with just a few little fish. There just wasn’t enough oxygen to support more life. Why was station #146 so huge? As the low oxygen waters spread out from the Mississippi River delta, critters were fleeing the hypoxia zone and moving to better water. So along the edge of the dead zone is an area with high population density; the oxygen refugees and the fish swooping in to eat them. However, not all creatures can move themselves out of the way. Creature like bivalves and gastropods (clams and snails) don’t have the capability to move much and so get caught in the annual hypoxic zone of the Gulf.

Bringing up the big catch at station 146

Hypoxia zones caused by nutrient runoff from fertilizer and other man-made sources do not just happen in the Gulf of Mexico. They have also been recorded in the Chesapeake Bay, Long Island Sound and at the mouths of rivers around the world. They can also happen in fresh water ponds and lakes.

The CTD is our main method of recording oxygen levels, but we need to make sure it is functioning properly. So each day we also take a water sample and use a titration method to find the amount of dissolved oxygen. Check out the colorful chemical reactions in this video.

Personal Log

People, like fish, need oxygen and water to survive. Out on the ship oxygen in the air is easy to come by, but fresh water is another story. We are surrounded by water of course, but cannot drink the salt water. I tracked down out Chief Engineer, Sean Pfarrer, to find out more about where all the fresh water on board comes from.

Down in the engine room there is a reverse osmosis machine that processes salt water and turns it into fresh water. The salt water is pumped into the machine under 950 psi of pressure. The pressurized water is forced through a selectively permeable membrane that lets water molecules through, but not the larger salt molecules. (My 6^th graders should find this all sounding familiar) The super salty water left behind is pumped back out to sea, and the fresh water is used on board. Our sinks, showers and laundry all use fresh water. We go through about 1,000 gallons a day, which is close to the 1,200 gallon limit of the RO system (but only about half what 30 average Americans would use on land). To conserve fresh water the heads (toilets in sailor speak) flush with salt water.

RO element — A rod from the RO machine. Water is pumped in the tube and forced through the yellow filter.

Which brings me to one of my favorite science teacher topics – poop. Thirty people over the course of fifteen days generate a fair amount of waste. What happens to all that poop? Just emptying it into the water would be harmful to the marine environment, so we have a little waste water treatment system right on board. When you flush, it all goes down to the marine sanitation device where poop eating bacteria consume our waste. The waste water then passes by chlorine tablets that kill any bacteria before it gets dumped into the sea. I’ll admit I’m a little fascinated by the systems and technology that keeps our floating community operating in a rather comfortable fashion.

We completed our science work this afternoon and are now heading back to port. Check out the Ship Tracker to see where we have been.

CDCPS Science Students:

How did sailors long ago during the age of exploration deal with the drinking water problem?

What do you think we could do to lessen the hypoxia problem in the Gulf?

July 5, 2013August 11, 2021

Sherie Gee: Eco-Friendly Ships, June 26, 2013

NOAA Teacher At Sea
Sherie Gee
Aboard R/V Hugh R. Sharp
June 26 — July 7

Mission: Sea Scallop Survey
Geographical Area of Cruise: Northwest Atlantic Ocean
Date: June 26, 2013

Science and Technology Log:

I was very pleased to learn that the R/V Hugh R. Sharp is environmentally friendly. I was lucky enough to run into some of the crew members that were getting the ship ready to leave the dock. One of the crew members named Tim, showed me around the ship and pointed out various features that keep the ship running. I noticed many piles of crystal salt bags and asked what they were for. That conversation led to the discovery of how this ship and many other research vessels recycle their water while out at sea. Water is categorized into three types: clean water, gray water, and black water. Clean water is used for drinking, showering and washing clothes and dishes. Gray water is the water that has been used after washing the dishes, clothes and other uses. This water is not potable but can be reused in other areas that do not need purified water. Then there is the black water that is basically “toilet water.” The toilet water is run through a reverse osmosis process which is where the salt crystals are used. Once the water has been through the process, then it can be discharged back into the environment; in this case, the ocean. It is now clean and safe enough for all organisms in the ocean. Of course they try to get some volunteers to test this water before discharging it into the ocean but haven’t gotten any so far.

Bags of salt crystals used in reverse osmosis

Along with the recycling of the water, the ship also recycles plastic bottles and aluminum cans. All trash such as paper, table scraps and other is bagged up and disposed of once they return to port. So nothing is thrown overboard.

He also explained that there are very stiff penalties for ocean pollution and not being in compliance. One accidental spill of any sort of substance that goes into the ocean is equal to a $10,000 fine right off the bat. This applies to all commercial fishermen.

Tim also discussed the portable laboratory vans which in this case is used as the wet lab. These vans can be relocated and used on any of the ships that need them.

Personal Log:

I have learned so much just in the first hour on board. I felt like a sponge absorbing all the new knowledge that I was receiving. There are so many people who make up the crew. Thanks to them for making the ship run smoothly. Then there are the research scientists that come on board. I would say about fifteen scientists. Many come from the University of Delaware, NOAA and Woods Hole. We were put into two teams: the day shift from 12:00 P.M. to 12:00 midnight and the midnight shift from 12:00 midnight to 12:00 P.M. in the afternoon. We had to pack our backpacks with everything that we thought we would need for that day because we were not allowed to go back to the stateroom because the other shift was sleeping. I was on the day shift and actually slept a good eleven hours between shifts.