# Presentation: 010659

## MARATHON ASHLAND PIPE LINE  ULSD TESTING

**Wesley Neff**
**November 20, 2002**

**Notes:**
EPA ULSD WORKSHOP – 11/20/02 

I plan to briefly describe the results of the ULSD testing performed by Marathon Ashland Pipe Line last year.

## Distribution Concerns

**The distribution system has no experience in handling ultra low specification product in a batched system**
**Off-highway /heating oil <5000 ppm**
**Jet Fuel <3000 ppm**
**Low sulfur diesel <500 ppm**
**Kerosene <2000 ppm**
**Ultra low sulfur diesel ,15 ppm**

**Notes:**
The distribution system has no experience in handling an ultra low specification product in a batched system. At 15 ppm sulfur, ULSD will be the lowest sulfur product in the distribution system.
Listed are Marathon Ashland’s distillate sulfur specifications. Assuming that the sulfur specification of ULSD in  pipelines will need to be about 10 ppm, and comparing that with heating oil at 5000 ppm, results in a product specification  ratio of 500:1. The system has only dealt with sulfur specification ratios in the 10:1 range. As an example a 0.10% contamination (10 bbls in 10,000 bbls) of 5000 ppm sulfur heating oil in ULSD will raise the sulfur content level by 5 ppm.

## Goals for MAPL ULSD Testing

**Determine whether sulfur from other refined products will “trail-back” in the pipeline**
**Determine what batch sequences will work and the amount of interface generated**

**Notes:**
Our refineries in Robinson, IL and Garyville, LA planned some test runs of ULSD in the summer and fall of 2001. We  decided to take advantage of this production of ULSD and perform some pipeline tests.

The next two slides list the goals for MAPL’s ULSD Testing
1) Determine whether sulfur from other refined products will “trail-back” in the pipeline
2) Determine what batch sequences will work and the amount of interface generated

## Goals for MAPL ULSD Testing (Con’t)

**Determine sulfur degradation due to:**
**The originating tank and receipt manifold piping**
**The pipeline and its associated appurtenances**
**The delivery manifold, tank piping and transport loading equipment**
**Determine an appropriate field test for sulfur**

**Notes:**
3) Determine sulfur degradation due to:
The originating tank and receipt manifold piping
The pipeline and its associated appurtenances
The delivery manifold, tank piping and transport loading equipment
4) Determine an appropriate field test for sulfur

## ULSD Testing 

**Initial tests conducted with Premium Gasoline on 4 pipeline systems**
**Many lessons about contamination learned**
**Precautions taken with ULSD tests**
**Automatic sumps were locked out**
**Booster pump units along the pipeline were not started**
**Simple tank to tank movements**
**Pipeline shutdowns minimized**
**Tank lines and tanks emptied prior to ULSD**
**Special sampling procedures implemented  **

**Notes:**
Since ULSD is not readily available, we did our first series of tests with premium gasoline. The premium gasoline had sulfur of 15 – 20 ppm. 
 We conducted gasoline tests on 4 pipeline systems. Some useful data was developed from the gasoline tests, but the best benefit were the lessons learned that were incorporated into the ULSD testing protocol.

Precautions taken with ULSD tests
Automatic sumps were locked out. We had one gasoline test spoiled because of a sump injection of high sulfur material into the test batch.
Booster pump units along the pipeline were not started unless they had been purged with ULSD
Our tests were conducted with simple refinery tank to terminal tank movements – no stops along the way
Pipeline shutdowns minimized – we scheduled our tests so that no pipeline shutdowns would occur while ULSD was in the system. Also, the lines used for the tests have minor elevation change
Tank lines and tanks emptied prior to ULSD
Special sampling procedures were implemented, making sure all sample lines were thoroughly flushed, samples taken with precise timing, and with detailed labeling 

## ULSD Testing 

**ULSD tests were conducted on 4 pipeline systems**
**10”, 12”, 16” and 20” diameter - 70 to 250 miles long**
**Garyville to Zachary test was the most recent**
**Test is representative of all tests**
**Test covered movement from Garyville refinery tankage to MAP’s tankage at Zachary, La**
**70 miles of 20” pipeline**
**Second test on this system in April, 2002 **

**Notes:**
ULSD tests were then performed on the same 4 pipeline systems, ranging in size from 10” diameter to 20”, 70 miles to 250 miles in length. 

The tests on our Garyville to Zachary System were the most recent ( September, 2001). I will briefly describe the results of the testing on this system  This test is representative of all the tests we performed. The ULSD batch tested was moved from MAP’s Garyville, LA refinery to MAP’s tankage in Zachary , LA (about  70 miles of 20” pipeline)

We ran a second test on this system in April, 2002

## ULSD Testing – Garyville to Zachary

**Garyville made 90,000 bbls of ULSD in mid-September, 2001**
**ULSD in tank had 10 ppm sulfur and API gravity of 38.7 degrees**
**ULSD from unit had 7 ppm sulfur**
**76,500 bbls lifted to Zachary**
**LSD at head end**
**Regular gasoline at tail end **

**Notes:**
MAP’s  Garyville Refinery made 90,000 bbls of ULSD in September, 2001.
The ULSD in the refinery tank had 10 ppm sulfur and an API gravity of 38.7 degrees
The ULSD at the refinery unit had 7 ppm sulfur.
The sulfur change between the unit rundown and the refinery tank is an indication of how easily ULSD can be contaminated.

76,500 bbls was lifted into the Garyville to Zachary 20” Pipeline with LSD (~400 ppm sulfur) at the head end and regular gasoline (~180 ppm sulfur) at the tail end 

## ULSD Testing – Garyville to Zachary Results (Con’t)

**Notes:**
We experienced some sulfur contamination at the head end of the ULSD at Garyville. 
This is an expanded plot of sulfur(y-axis) vs. bbls (x-axis) at the head end of the batch. Samples were taken at each end of the pipeline, and at  Plantation Jct which is at the 3⁄4 point on the pipeline. Note that the sulfur content is elevated for over 4000 bbls. Also note that the sulfur profiles are essentially the same at Garyville, Plantation Jct and Zachary. Once the contamination occurred, it did not “trail back” into the batch.  The contamination occurred in the refinery tank line from the refinery tank to the pipeline manifold. The tank is at the end of a long tank line which passes by several other tank connections (or dead leg piping ) before reaching the pipeline manifold. These connections apparently had higher sulfur/lower gravity distillate in them that contaminated the ULSD batch as it passed.  

As I mentioned earlier, we did a second test at the head end of an ULSD batch from Garyville in April. The refinery attempted to flush the tank line prior to lifting the ULSD batch into the pipeline. The results were disappointing – and nearly identical to the prior test. 

## ULSD Testing – Garyville to Zachary Results (Con’t)

**Notes:**
This is the tail end sulfur profile of the batch at Plantation Jct and Zachary - 1000 bbls long, and more typical of what current critical interfaces (ie gasoline/distillate) are on the system.

## ULSD Testing – Garyville to Zachary Results (Con’t)

**Notes:**
This is the head end interface sulfur and gravity profile as it arrived at Zachary. Note that the sulfur and gravity profiles are nearly identical. Since there was no way to determine the sulfur content of the products, we made our switches from adjacent product to ULSD based upon the gravity of the products. As you will see on the next slide, this provided the ULSD batch reasonable protection from contamination 

## ULSD Testing – Garyville to Zachary Results (Con’t)

**Zachary via 20” system wrapped with LSD and gasoline**
**73,034 bbls out of 76,588 bbls delivered to a clean tank at Zachary **
**1-2 ppm sulfur degradation tank to tank **
**4.6% loss to interface**
**Refinery tank line at Garyville contaminated head end 4000 bbls**
**No migration of sulfur at head end or tail end beyond the normal gravity interface zone **
**No degradation due to the pipeline and associated appurtenances**
**No sulfur degradation from delivery piping**

**Notes:**
Results:
73,034 bbls of ULSD out of 76,588 bbls lifted were delivered to a clean/empty tank at Zachary 
There was 1-2 ppm sulfur degradation between the tank at Garyville and the tank at Zachary. The sulfur level at Zachary was 11-12 ppm. 
4.6% was lost to interface
The refinery tank line at Garyville contaminated 4000 bbls at the head end of the batch
The rest of the results are the same as we saw on our tests in 3 other systems,IE:

There was no migration of sulfur at the head end or tail end interfaces beyond the normal gravity interface zone

There was no sulfur degradation due to the pipeline and its associated appurtenances

And there was no sulfur degradation from the delivery piping at Zachary.

This batch was then moved through the Colonial Pipeline System, and Buster will describe their test results in a few minutes.

## Testing Summary

**MAPL results indicate:**
**Pipelines can transport ULSD and maintain the sulfur specification**
**Gravity changes correspond closely to sulfur changes; protective gravity cuts may be acceptable**
**The loss to interface should be the same as with current critical cuts**

**Notes:**
To summarize the results of our ULSD tests:

Pipelines can transport ULSD and maintain the sulfur specification

Gravity changes correspond to sulfur changes; protective gravity cuts may be acceptable (I will talk about this more when I discuss in-line testing)

The loss to interface should be the same as with current critical cuts

## Testing Summary (Con’t)

**MAPL results indicate:**
**Contamination occurs from front end systems such as refinery piping and origin station piping**
**Little sulfur contamination occurs in the pipeline **
**Tankage and delivery system piping does not add significant sulfur contamination**

**Notes:**
Contamination (in our tests) occurred in front end systems such as refinery piping and origin station piping

Little sulfur contamination occurs in the pipeline 

Tankage and delivery system piping does not add significant sulfur contamination

Keep in mind that all of our testing was done from refinery tank to terminal tank, with no stops in between. As compared to some systems, our lines are relatively short and small diameter. We did the tests under ideal conditions.

## Testing Conclusions 

**Must have in-line testing equipment**
**Control contamination that happens during transit**
**Define cut points**
**Suitable test equipment is not available**
**Test equipment must be robust**
**May need an indirect method for interface detection**

**Notes:**
Pipeline operators need in-line  sulfur testing equipment that can operate remotely and quickly. Monitoring the sulfur content of product in a flowing line has never been necessary, and fast acting field equipment is not available. 
The industry needs something that will find contamination that may have happened to the ULSD batch while in transit and allow the operator to take action before off-specification material enters terminal tanks. 
The same in-line equipment is needed to help define cut points. Since sulfur content in an interface changes more rapidly than gravity. it would be desirable to be able to see sulfur as well as gravity during an ULSD cut. Also, there may not be an adequate gravity difference between the ULSD and wrap material to facilitate a cut. Without in-line equipment, protective cuts will be necessary increasing the amounts of interface created.
The test equipment needs to be robust and able to operate at a remote location with only periodic attention. Needs to be able to handle dirty product, water, etc. 
If in-line equipment is not developed, we may need to use a surrogate property to identify change such as a dye or some other type of marker.

## Testing Conclusions (Con’t)

**Each pipeline system will have its own “personality” **
**Anything which creates a product quality problem today will be exacerbated when handling ULSD**
**Slow actuating valves – leaking valves**
**Non-dedicated tank lines**
**Long dead-legs in stations – long suction/discharge piping at pump stations**
**Sumps that inject automatically – prover loops that are not flushed**
**Systems with frequent shutdowns or large elevation differences**
**May need to redesign facilities to minimize contaminaiton**

**Notes:**
Each pipeline system will have its own “personality”, and batch sulfur specifications will need to be adjusted accordingly. Anything which creates a product quality issue problem today will be exacerbated when handling ULSD. Concerns include: 
Non-dedicated tank lines
Non-dedicated suction/delivery headers
Long dead legs in stations
Leaking valves
Long suction/discharge piping at pump stations
Sumps that inject automatically
Prover loops that are not continuously flushed
System shutdowns and systems with large elevation changes
Some facilities may need to be redesigned to minimize contamination.

## Testing Conclusions (Con’t)

**Pipeline ULSD sulfur specifications could vary by system or routing**
**Simple tank to tank movements could add only 1 ppm sulfur with a moderate interface loss**
**More complex network routings could add several ppm sulfur and have a large loss to interface **

**Notes:**
The pipeline ULSD sulfur specification might need to vary batch to batch depending on the origin and destination. For example, sulfur degradation for a simple tank to tank movement from a refinery to a terminal should  be about 1 ppm. More complex pipeline network movements that involve passing through breakout tanks and multiple pipeline segments could result in a several ppm sulfur degradation. These will need to have lower sulfur at the origin.

## DISCUSSION