How To Clean A Syphun Pump Of Oil

I wrote a brief post almost ODME some time back merely this post is going to be in detail. More and more companies are at present focusing on saving the environment. Oil major do non seek to engage with company that do non consider environmental aspects in their 24-hour interval to day work.

And so far and so that it is not enough nowadays to simply fulfil the legal requirements. Anybody wants us to go beyond legal requirements.

ODME is i of the equipment which ensures surround compliance on board ships.

Only in that location continues to be detention because of ODME non-compliance. These non-compliance are old intentional just many times unintentional. Visitor should focus on developing a safe culture which can take care of intentional non-compliance.

Merely thorough knowledge of the equipment such as ODME is the only fashion to avoid unintentional non-compliance. This guide can assistance usa to be more enlightened of ODME by knowing more most it.

What is ODME for ?

Well if you are reading this, most likely you know what is ODME for. But lets yet ask information technology. Why do we need ODME? Can't we just ban throwing oily mixture overboard and country information technology with barge.

We are concerned about the environment only in that location are businesses to sustain. Send owners would argue that they should exist allowed to dispose the h2o office of the oily mixture into the sea ?

ODME brings a residue between "do non throw oil into sea" and "reduce operational costs" to the ship owners.

Simply sometimes we forget that the purpose of ODME is to remove water from the slops and not as much oil as is immune.

How does ODME do information technology ?

Broadly speaking ODME controls the performance of these two valves shown in the below diagram.

These two valve will never be open or close together. If i is open, the other will be in close position.

We know that Marpol Addendum I regulation 34 lists the conditions in which oily mixtures can be tending into the sea.

When conditions number 4 & v are satisfied, ODME volition open the overboard valve to allow the disposal of oil h2o.  Whenever nosotros exceed whatever of these two atmospheric condition, ODME will close the overboard valve and open slop valve.

Now for doing this task, ODME need to  measure

• Instantaneous rate of belch to ensure that it is non more than 30 L/NM
• Total quantity discharged to ensure that information technology is non more than required

So lets see what all components help ODME mensurate these things.

What all components make ODME

If you call up, the formula for Instantaneous rate of belch is

Now if ODME need to measure IRD, it surely need values for oil content in PPM and Flow rate.  Speed connection is commonly given either from log or GPS.

All these values are fed to the computing unit of the ODME. Computing unit of measurement does all the mathematical calculations to get the required values. Nearly of the times you will discover the computing unit of measurement in Cargo control room. Now lets meet how and from where the computing unit of measurement gets these values

Menstruation rate

ODME computing unit gets the flow rate from flow meter. A small sample line goes from the main line, pass through the menstruum meter and goes dorsum to the main line. Flow meter calculates the flow in m3/Hr and gives this value to the computing unit through a signal cable.

Measuring PPM

Measuring cell is the component that measures the amount of oil (in ppm) in the water. Measuring jail cell is located in a chiffonier called "Analysing unit of measurement". Well-nigh of the times you volition notice "Analysing unit" in the pump room.

The measuring principle relies upon the fact that dissimilar liquids have unlike light handful characterstics. Based on the low-cal scattering design of oil, measuring cell determines the oil content.

The sample water is passed through a quartz drinking glass tube. And the oil content is determined past passing this sample water in different detectors in series.

But to measure out PPM in a h2o sample, a sample from the belch water demand to laissez passer through the measuring prison cell. This job is done by a sample pump.

Sample pump draws the sample from the discharge line before the discharge valves. This sample is sent to the measuring cell (in analysing unit of measurement) for measuring the oil content and and then sent back into the same discharge line.

It is important that sample pump not run dry out or with excessive discharge force per unit area. To avoid this situation, a pressure sensor is fitted inside the analysing unit of measurement. This force per unit area sensor measures the inlet and outlet force per unit area of the sample pump.

Measuring prison cell should always get the continuous flow of the sample so that the most current sample is analysed. The pressure sensor also eliminates the possibility of running the ODME with sample valves closed.

The measuring cell need to be cleaned regularly during the operation. This is to avert any deposits of oil traces around measuring jail cell which tin give wrong readings. To clean the measuring cell, ODME runs cleaning cycle in pre-divers interval during its operation. The cleaning cycle involves flushing the jail cell with fresh water.

Cleaning line and sample lines into the measuring cells are segregated by pneumatic valves. So when cleaning cycle is initiated following takes identify

• The pneumatic valve of the fresh h2o line into the measuring cell opens
• The pneumatic valve of the sample line into the measuring cell closes
• If the ODME has provision for detergent injection, the required amount of detergent will be injected during the cleaning cycle

We need to make certain that the detergent tanks is not empty and nosotros use maker recommended detergent only.

So there are three additional lines you volition find going into analysing unit for cleaning bicycle.

• Fresh h2o line for the cleaning of measuring cell
• Air line for operation of pneumatic valves
• Cleaning solution line for meliorate cleaning of the measuring prison cell

The analysing unit sends the information values similar pressure and oil content to the calculating unit of measurement in the CCR. Depending upon the make, the analysing unit send these values either direct to computing unit or through converting unit.

If a converting unit of measurement is fitted, information technology may be doing additional tasks similar controlling the cleaning cycle.

The calculating unit calculates the IRD based upon all these values fed to it. If the IRD is less than xxx L/NM, it gives the command to solenoid valve assembly to open the overboard valve and close slop recirculation valve. When the IRD becomes more 30 50/NM, it closes the overboard valve.

The computing unit also calculates the amount of bodily oil that has been discharged to sea. The requirement is that we cannot belch total oil more than than 1/30000 of the total cargo carried. Before we starting time ODME, we need to calculate and feed this maximum allowed value in the ODME. This we volition hash out afterward in this mail.

Just as yous tin see, slowly we take created a basic line diagram of ODME. Now if you lot tin take out the line diagram of ODME on yous vessel, cheque if you tin can chronicle to information technology. I randomly took a line diagram of one of the make to encounter if we tin place the parts and line of ODME ? I could, can you besides place in the below image ?

If y'all could, Very well. Merely if you still want the answers, here is it in the below image

Now that nosotros are clear on what ODME is fabricated upward of and well-nigh the components of ODME, lets run across how senior deck officeholder should operate ODME.

Operation of ODME

As we know ODME is required under Marpol Annex I, which deals with pollution aspects related to oil cargoes. At present in 10 steps lets encounter how nosotros should use the ODME.

Lets assume we are on a production tanker of 45000 DWT which has merely discharged an oil cargo of 29000 MT (30000 m3 @ 15 C). This tanker demand to make clean these tanks which were carrying total oil cargo of 29000 MT. How to proceed with cleaning and decanting the slops with ODME ?

Step 1: Set the total oil quantity in ODME

Marpol has put a limit on how much total oil nosotros can discharge in the launder water. This limit is 1/30000 of the total cargo carried. Then in our example of product tanker, lets summate

Total Cargo carried in the tanks to be cleaned : 30000 m3 @ 15 C

Total oil from the washing that can exist discharged = 1 m3 (1000 litres)

Set the total oil limit as k litres in ODME. Lets demonstrate this in ODME of make Rivertrace technology.

To set up the total oil limit, go to Oil dischrage under Manner selection by pressing the enter button (center one).

Under "Oil Discharge Fix Upwards", become to "warning limit" and press enter.

Ready the new value by Upwards and down arrows and press enter.

It will ask to confirm, which we will and we take now set the max oil discharge limit.

2. Allow minimum 36 hours settling time

We will wash the tanks and collect the slops in slop tank. But before we tin showtime pumping out oily water through ODME, we need to allow a minimum of 36 hours settling time. This settling fourth dimension ensures that the oil has separated completely from the water.

We may argue that if our discharge is limited to 30L/NM, then what difference does information technology make with settling time ? But the fact is that even when we tin use the ODME to discharge oily water, nosotros must ensure that the oil is minimum in the h2o.

three) Check all other conditions in Marpol Annex I, Reg 34

We must ensure that other conditions related to vessel existence enroute, minimum speed and distance from nearest state is OK.

four) Prepare ODME for functioning

After we are satisfied with all conditions, nosotros can prepare to first overboard discharge of the slops.

We already discussed what components are nowadays in ODME and what are their functions. So we know what we need to exercise to set up ODME for operation. Offcourse it could be little different on unlike vessel simply most of the things will exist mutual. We must check and locate each item mentioned in the manual. Here is epitomize of some of the common items need to check before ODME operation

• Check if the inlet and outlet valves for flow meter are open
• Bank check if Fresh h2o supply is available and all valves are open
• Cheque if sample line inlet and outlet valves are open
• Check if air supply for pneumatic valves is on.
• Check if cleaning solution is present in the container
• Check if power supply is on for the converter unit
• Check & rotate the sample pump shaft with hand to check if it is free to move

Too check and confirm that all values are in machine and non in manual mode. These values to check are for flow rate, speed and PPM.

5) Start the cargo pump in recirculation way

One time nosotros accept set up the ODME, we can start the slop tank pump containing oily h2o in recirculation fashion. Now fifty-fifty when it is running on the recirculation manner and overboard valve is closed, on some equipments you can check the IRD in the CCR ODME screen. If you lot see some strange valves, for case loftier PPM of oil in sample, end the pump and

• either start a cleaning cycle manually, if that part is nowadays in the ODME
• or Clean the measuring cell manually with maker'southward tool as would be described in the ODME transmission

6) Get-go overboard belch

Later all the above steps are completed and verified, we tin can start the ODME to commence overboard belch.

7) Monitor during entire overboard discharge operation

Now if everything is going fine, carefully monitor following

The discharge h2o is not making whatsoever visible sheen on body of water surface. Remember y'all dont need any torch to run into that. You demand to do the overboard discharge operation during daylight only.

Check and monitor the values for oil in water (PPM) and IRD. If IRD is close to 30 L/NM, you dont want information technology to cross 30L/NM and finish the functioning. In this case y'all tin reduce the pump speed to reduce the flow. With flow rate reduced, the IRD will reduce too.

Monitor the oil water interface level past MMC or UTI tape. This is of import because we are serious about the environment. We want to stop the overboard discharge few centimeters before nosotros achieve the oil surface. This shows our seriousness to salve the environment. The too shows that our aim was non to dischrage as much oil equally we can but was to belch as much clean water as we tin can.

Moreover nosotros practise not want to spoil our ODME system by allowing the oil to enter into the organisation.

8) Stop the overboard belch

The ODME volition stop automatically when either the IRD exceeds 30L/NM or we accept cross the total oil dischrage limit.  But we should exist ready to stop the ODME manually as well. Nosotros should stop the overboard discharge manually when either of the post-obit happens

• We take reached the interface level
• Rapid increase in PPM. Nosotros can continue if we are sure that oil water interface is withal very far.
• We see some oil sheen on the sea surface

9) Do not start the ODME multiple times

If the ODME is stopped automatically considering of IRD exceeding 30L/NM, we must not offset the ODME again. Some people start the ODME over again to check if they tin nevertheless be able to reduce the onboard quantity. Even when you can argue that y'all are doing so through ODME, y'all are actually voilating MARPOL unintentionally. Many vessels were detained past Paris MOU for multiple attempts to offset ODME. The detention has a logic and following reasons

• By multiple starts, the operator is trying to throw as much oil overboard as he can
• Once ODME stops automatically, the operator need to allow farther 24 hours of settling time to start the ODME again. This is because if the level of oil/water mixture is very less, on recirculation this would accept churned. Now to have the h2o separate out from oil, we need to allow it 24 hours.

But if the ODME had stopped because of some error when the water level was still high, there is no need to expect for another 24 Hour settling fourth dimension.

ix) Perform the cleaning cycle

Each time ODME is stopped, a cleaning cycle will start. But if information technology does not showtime automatically, we can first the cleaning cycle manually.

ten) Close all the valves and system

Once the ODME operation is complete, we can close all the valves and electric power. We tin then make a entry in oil record book for this functioning.

Conclusion

At that place has been number of detentions and hundreds of observations on incorrect use of ODME. These detentions likewise include willful wrong operation of ODME.

At that place were few cases where seafarers had bypassed the ODME even when ODME was in perfect shape and working. This was because, the seafarers sometimes feel that an equipment such as ODME is hard to operate.

But if we know our equipment well, not only these will seem piece of cake to operate simply besides will operate perfectly.

Source: https://www.myseatime.com/blog/detail/a-step-by-step-guide-of-how-to-operate-odme-and-principle-of-its-operation

Posted by: voglnevill.blogspot.com

Share this post