AKJLexLab Coal Test Report - AKJ · PDF fileThe harder the coal, the less fines the handling process ... control testing on the material at ... increases in surface moisture. The coal

AKJLexLab

Coal Test

Report

November 18

2012 The following report is a summary of testing performed at the University of Kentucky School of Mining on coal submitted by ABC mining. We welcome the opportunity to come view the testing process in person.

Personalized report

highlighting your specific

coal handling challenges

AKJLexLab Coal Test Report 2012

1 ABC Mining

Contents

I. Surface Moisture .................................................................................................................................................................2

II. Size Fraction .........................................................................................................................................................................2

III. Hard Grove Index ..............................................................................................................................................................3

IV. Moisture Footprint.............................................................................................................................................................3

A. Dust Control ............................................................................................................................................................................4

B. Wet Coal Flow.........................................................................................................................................................................4

C. Freeze Control ........................................................................................................................................................................5

1. Side Release ...................................................................................................................................................................5

2. Body Feed .......................................................................................................................................................................6

V. Dust Control Testing ........................................................................................................................................................7

VI. Wet Coal Flow Testing ....................................................................................................................................................8

VII. Freeze Conditioning Testing...........................................................................................................................................9

A. Side Release ..............................................................................................................................................................................9

B. Body Feed................................................................................................................................................................................ 10

VIII. HotShot Testing ............................................................................................................................................................... 11

IX. Car Top Binder Testing................................................................................................................................................. 12

X. Coal Pile Sealant............................................................................................................................................................... 13

XI. SponCom Testing ............................................................................................................................................................ 13

Thank you! ................................................................................................................................................................................... 14


2 ABC Mining

I. Surface Moisture

When the coal sample was submitted (10/27/12) the moisture was tested using a moisture analyzer:

Figure 1 - Moisture Analyzer

The results of that test are as follows:

As Received:

- Surface Moisture: 12.1%

- Total Moisture: 15.4%

After 48 hour air dry (coal was spread to a depth of approximately 1 inch)

- Surface Moisture: 4.2%

II. Size Fraction

Upon receipt the coal was coned and split into 10 lb samples. One sample was sieved to determine the

amount of float dust by weight. Float dust is defined by any particle 200 micron or smaller.

As Received:

Float Dust (by weight): 11%

The 10 pound coal sample was then crushed to 1/4 inch minus and sieved again.

After crushing to 1/4 inch minus:

Float Dust (by weight): 17%


3 ABC Mining

III. Hard Grove Index

Most material handling challenges that AKJ attempts to treat are predicated by the amount of surface

area that requires treatment. Knowing the amount of fines in a specific coal is critical, but it is also

important to analyze how hard or soft a coal might be. The hardness of the material determines how

much it will break up during routine handling and create new surface areas. AKJ utilizes a Hard Grove

device to catalogue coals and determine how relative hard or soft the material is.

Figure 2 - Hard Grove Device

The harder the coal, the less fines the handling process will create. The softer the coal, the more fines

created and the more surface area requiring treatment.

- HG Index: 38

IV. Moisture Footprint

Nearly all material handling challenges can be linked back to the surface moisture present on the coal in

question. The lower the surface moisture, the dustier the coal. The more susceptible a coal is to

wet coal flow challenges and the harder it is to effectively freeze treat. In addition, dramatic swings in

surface moisture can increase the likelihood of spontaneous combustion. AKJ subjects coal samples to a

battery of tests at a wide range of surface moisture levels to create what we call a moisture footprint.


4 ABC Mining

0

25

50

75

100

125

150

4.00% 6.00% 8.00% 10.00% 12.00%

MAX

AVG

Figure 3 - AKJ's DustCube and a TSI DustTrak

A. Dust Control

Dust levels at lowest surface moisture level (4.2%)

- Average: 94 mg/m^3

- Max: 150 mg/m^3

Dust levels at 6%


- Max: 111 mg/m^3

Dust levels at 8%

- Average: 4.2 mg/m^3

- Max: 19 mg/m^3

Dust levels at 10%


- Max: 0.91 mg/m^3

Dust levels at 12%


- Max: 0.84 mg/m^3

B. Wet Coal Flow

As the surface moisture increases and dust becomes less of an issue, wet flow challenges often begin to

arise. Wet flow issues include coal build up on vertical surfaces, rat holing and even complete bridging

or plugging. This is caused by hydrogen bonding and occurs when the hydrogen bonds are strong

enough to not allow coal particles to fall into free space. To test this phenomenon, AKJ utilized a steel

hopper outfitted with an oscillating vibrating feeder. 10 pound samples are loaded into the hopper and

the amount of coal that passes through the device is measured. As the surface moisture on the coal is


5 ABC Mining

raised, more coal hangs up in the corners of the hopper and when the surface moisture becomes high

enough complete bridging occurs.

Weight at 4.2% (amount of the 10 pound sample that passes through the hopper)

- 9.98 lbs.

Weight at 6%

- 9.20 lbs.

Weight at 8%

- 7.41 lbs.

Weight at 10%

- 1.47 lbs.

Weight at 12%

- 1.48 lbs.

C. Freeze Control

As you would expect, freeze proofing coal is more challenging as the surface moisture increases. AKJ

evaluates two types of freeze conditioning; side release and body feed.

1. Side Release

Moving coal in rail cars during harsh winter conditions can be challenging. Frozen coal can build up on

the vertical sides of rail cars creating a layer of carry back. This can increase unloading times and lower

coal yields, both of which are detrimental to the bottom line. To simulate this challenge in a lab setting,

AKJ freezes coal to steel plates for 24 hours at 5°F. A shear testing device is then used to determine

the amount of force required to break the frozen bond.

Figure 5 - Steel Coupons

Figure 6 - Shear Testing Device

Figure 4 - Hydrogen Bonding


6 ABC Mining

Shear Force at 4.2%

- 1,852 grams of force

Shear Force at 6%


Shear Force at 8%

- Overload (greater than 6,800 grams of force)

Shear Force at 10%


Shear Force at 12%


2. Body Feed

In addition to applying side release agents, the coal itself needs to be treated to prevent large chunks of

frozen material or pigs. Pigs can clog up grizzly bars and delay the unloading process as well as increased

wear and tear on unloading equipment. To simulate this material handling challenge, AKJ forms half

sphere molds of the coal being tested and then freezes those molds at 5 degrees F for 24 hours. Each

one is made up of precisely 50 grams of coal. The coal won’t hold the form at lower surface moisture

levels (below 8% in this case).

Weight after 1 minute in shaker at 8% (amount that passes through a ¼ sieve)

- 38 grams

Weight after 1 minute in shaker at 10%

- 31 grams

Weight after 1 minute in shaker at 12%

- 8 grams

Figure 7 - Carryback

Figure 8 - Coal Pigs


7 ABC Mining

V. Dust Control Testing

As discussed in the previous section (IV. Moisture Foot Print), the coal in question is very dusty

between 4.2% and 8% surface moisture. Once it reaches 8% the dust levels begin to decline. For that

reason, AKJ focused dust control testing on the material at the dried material (4.2% surface moisture).

The AKJ DustBox (Figure 3) is utilized to determine the effectiveness of various products and their

ability to control dust on this specific coal. The DustBox simulates a transfer point in a material handling

unit by subjecting the coal to free fall and impact and introducing an increase in air velocity. A TSI

DustTrack (also in Figure 3) is used to quantify the results.

10 pound samples are used and each one is run through untreated initially. The dust levels (maximum

and average) are recorded and then the coal is treated and adequately mixed (achieving good coverage

is critical). The coal sample is then run through the DustBox again and dust levels are recorded to

determine how effective the treatment was. Note that reusing the same sample does not result in

lower dust levels (illustrated in the video linked here).

Sample 1 - Untreated


- Max: 150 mg/m^3

Sample 1 - Treated at 0.5 gallons per ton with AKJ’s FC-200


- Max: 12.56 mg/m^3



- Max: 150 mg/m^3

Sample 2 - Treated at 0.5 gallons per ton with AKJ’s EnviroGreen 2600


- Max: 8.68 mg/m^3

Note that this is a very severe test conducted in a small, confined space. AKJ would expect the dust

levels represented above to be lower in actual field conditions. No products currently being used on

this coal in the field were provided for testing.

http://www.progresstechnologies.com/akjindustries/productsservices/dust-control/utility/

http://www.youtube.com/watch?v=BCznXvAGU94


8 ABC Mining

VI. Wet Coal Flow Testing

As discussed in section IV. Moisture Foot Print, wet flow testing is conducted using a vibrating hopper

to determine how well coal moves through a tapered enclosure as it increases in surface moisture. The

coal in question is very susceptible to this material handling challenge. The material started to stick in

the corners of the hopper at 8% surface moisture and complete plugging began to occur at 10% surface

moisture.

AKJ offers two products to alleviate wet coal flow challenges: DrySorb and ReleasEZ.

DrySorb is a dry product that effectively absorbs the surface moisture present and converts it to a

lubricating gel. The material works quickly, but does not achieve full absorption for 30 minutes. Ideally,

Drysorb would be used in scenarios where the coal can be treated as far “up stream” from the problem

area as possible.

Sample 1 (8%) - Untreated (amount of the 10 pound sample that passes through the hopper

- 7.82 lbs.

Sample 1 (8%) - Treated with ¼ pound per ton of AKJ DrySorb

- 9.97 lbs.

Sample 2 (10%) - Untreated

- 1.51 lbs.

Sample 2 (10%) - Treated with ½ pound per ton of AKJ DrySorb

- 9.98 lbs.

Sample 3 (12%) - Untreated

- 1.44 lbs.

Sample 3 (12%) - Treated with 1 pound per ton of AKJ DrySorb

- 9.93 lbs.

When DrySorb is not the answer due to application challenges, AKJ offers ReleasEZ. ReleasEZ is a wet

product that treats the surface moisture present to weaken the hydrogen bonds and restore flow. It

does not require time to work, but sufficient mixing in the coal stream is critical to performance. When

at all possible the product should be applied at a transfer point where the coal is in free fall.

Sample 1 (8%) - Untreated (amount of the 10 pound sample that passes through the hopper)

- 6.12 lbs.

http://www.progresstechnologies.com/akjindustries/productsservices/wet-flow/

http://www.youtube.com/watch?v=BU8TjCRWvZU

http://www.youtube.com/watch?v=KvGqw8T1qSQ


9 ABC Mining

Sample 1 (8%) – Treated with ½ gallon per ton of AKJ ReleasEZ

- 9.83 lbs.

Sample 2 (10%)– Untreated

- 1.46 lbs.

Sample 2 (10%) – Treated with 1 gallon per ton of AKJ ReleasEZ

- 9.58 lbs.

Sample 3 (12%)– Untreated

- 1.32 lbs.

Sample 3 (12%) – Treated with 1 gallon per ton of AKJ ReleasEZ

- 9.55 lbs.

Note that the coal being tested responded well to both products applied. The DrySorb product was

given 5 minutes to perform before the treated sample was run back through the hopper. No products

currently being used on this coal in the field were provided for testing.

VII. Freeze Conditioning Testing

The first freeze conditioning test performed was to determine the effectiveness of AKJ’s side release

agent, FreeFlow SR300. SR300 was designed to coat the inner walls of a rail car before it is loaded with

coal . The material contains AKJ’s proprietary additive, SurfaceBond, to help it adhere to the vertical

steel or aluminum surfaces and resist runoff. As discussed previously in this report (section IV), a shear

testing device is used to determine the amount of force it takes to break frozen coal from a steel

coupon (Figure 5 and Figure 6).

A. Side Release

Shear Force at 4.2% - Untreated steel coupon


Shear Force at 4.2% - Steel treated with FreeFlow SR300

- 145 grams of force

Shear Force at 6% - Untreated steel coupon

http://www.youtube.com/watch?v=TLMr1OpBu1o

http://www.youtube.com/watch?v=nweroZ1E4SE

http://www.youtube.com/watch?v=hdfDTsA4eRM


10 ABC Mining


Shear Force at 6% - Steel treated with FreeFlow SR300














Note that the steel coupons are treated by dipping them into the freeze conditioning chemical and then

hung vertically for 1 minute. The amount of product that stays on the coupon is measured and

recorded. In the event that competitive products are supplied AKJ offers data on how much product is

still present on the coupon after 1 minute (this is done to simulate the product loss after a car is treated

but before it is loaded with coal). No products currently being used on this coal in the field were

provided for testing.

B. Body Feed

Body feed products are tested by evaluating their ability to weaken ice crystals between coal particles.

Coal is frozen into half spheres (this shape is used because it is the easiest way to create samples of

close to identical size, weight and compression) and then frozen at 5 degrees F for 24 hours. The

frozen sample is then placed in a sieve container outfitted with a ¼ inch screen. The container is placed

in a shaker for 1 minute. After 1 minute, the frozen sample is then weighed to determine how much

frozen material was unable to break up.

http://www.youtube.com/watch?v=vUAUxNNfFqo


11 ABC Mining

Sample 1 (8%) – Untreated (portion of the 50 gram frozen sample that passes through a ¼ sieve)

- 41 grams

Sample 1 (8%) – Treated with FreeFlow FC-100 at 2 Pints Per Ton

- 49 grams

Sample 2 (10%) – Untreated

- 29 grams


- 44 grams

Sample 3 (12%) – Untreated

- 6 grams


- 40 grams

No products currently being used on this coal in the field were provided for testing.

VIII. HotShot Testing

When cars are not treated effectively or not treated at all, carry back can begin to occur. Carry back is

simply a layer of frozen coal on the inside of a rail car that did not unload. Typically, once carry back

occurs in a rail car it stays there until the weather breaks. This can delay unloading times, reduce coal

yields, and drastically increase the likelihood of derailments to cars by making them out of balance. AKJ

simulates carry back by freezing a one-inch compacted layer of coal to an untreated steel coupon. We

then apply SR300 to the top of the frozen coal to simulate spraying a “dirty car” with a side release

agent. It is critical to note that SR300 was designed to coat and prevent freezing from occurring, not to

penetrate and melt already frozen material. AKJ’s HotShot is then applied to the top a frozen coal

sample. Both sample are left in the freezer and then tested using the shear testing device to determine

how effective they are at melting away the carry back.

Shear Force at 10% - Topped with SR300 and tested 10 minutes later


Shear Force at 10% - Toped with HotShot and tested 10 minutes later

http://www.progresstechnologies.com/akjindustries/productsservices/freeze-conditioning/hotshot/

http://www.youtube.com/watch?v=sC7z2dTK_iE


12 ABC Mining


Shear Force at 12% - Topped with SR300 and tested 10 minutes later


Shear Force at 12% - Toped with HotShot and tested 10 minutes later


IX. Car Top Binder Testing

Dust emissions from rail cars in transit are becoming more and more of a problem. AKJ has

participated in a 5 year study conducted by the BNSF that resulted in 3 car top binding products being

approved for use. AKJ’s CTS-100 was one of those products and has been used to treat more than 75

million tons of coal. In an effort to constantly improve our product line, AKJ operates a wind tunnel at

the University of Kentucky to test various products and additives. The coal in question is loaded into

simulated rail cars and then treated at various application rates with AKJ’s newest car top binding agent,

DustLock 2012. It is then subjected to the wind tunnel, capable of sustained wind speeds of 60 MPH.


- Failure at 30 MPH

Sample 2 – Treated at 10 Gallons per Car

- Failure at 50 MPH

Sample 3 – Treated at 12.5 Gallons per Car

- Withstood 60 MPH winds

Sample 4 – Treated at 15 Gallons per Car

- Withstood 60 MPH winds

When initially developing the test, AKJ quantified the results by weighing the cars before and after

subjecting them to the wind tunnel. We quickly learned that the test is a pass/fail scenario. At high

wind speeds, as soon as the crust is compromised a layer of untreated material is exposed to the wind

and the coal profile rapidly erodes. No products currently being used on this coal in the field were

provided for testing.

Figure 9 - Dust in Transit

http://www.progresstechnologies.com/akjindustries/productsservices/dust-control/in-transit/

http://www.youtube.com/watch?v=ty4C9PfnUWk


13 ABC Mining

X. Coal Pile Sealant

Storing coal comes with an array of challenges. Significant dusting concerns, loss in coal quality, increase

in moisture and even spontaneous combustion. AKJ 100LX is used to seal coal piles for weeks and even

months at a time to combat each of these issues. By creating a water proof, durable outer crust, the

pile will no longer emit dust even during the hot summer months. In addition, sealing the pile limits

moisture intake and reduces oxidation to maintain the highest coal quality possible. It also reduces the

amount of airflow through the pile which reduces the risk of spontaneous combustion. A coal “puck”

will be sent along with this report that showcases the powerful bind AKJ 100LX creates on the coal in

question.

XI. SponCom Testing

Figure 10 - AKJ's SponCom Testing Device

AKJ funds a fellowship program at the University for a Master’s level student. Our current project is to

simulate spontaneous combustion in a lab setting in order to evaluate various coals and how susceptible

they are to the phenomenon. An adiabatic device was created that analyzes how a specific coal sample

reacts as it oxidizes. Oxidation is an exothermic reaction that generates heat. If that heat is not able to

dissipate, it can often build to the point of spontaneous combustion.

The device is used to assign a K value to each coal, which is simply the rise in temperature (degrees C)

as a function of time. Specifically, we are determining how many degrees a sample rises per hour. If the

K value is below 2.0, the coal is not likely to experience spontaneous combustion. As the value

increases above 2.0 it represents a material that is far more susceptible to the phenomenon.

The K value for the coal in question: 1.3

http://www.progresstechnologies.com/akjindustries/productsservices/dust-control/coal-pile-storage/

http://www.youtube.com/watch?v=Num9j6ODWGk

http://www.progresstechnologies.com/akjindustries/productsservices/spon-com/


14 ABC Mining

Thank you!

We appreciate you taking the time to submit coal samples and to learn more about what AKJ's line of

products have to offer. We welcome the opportunity for personnel from your company to come view

the testing first hand at the University of Kentucky School of Mining. Feel free to contact Trey Cranfill

(859.420.8739 or [email protected]) to arrange a visit or to ask any questions regarding the

testing process and/or results. We hope you found the report to be useful and look forward to helping

you solve any material handling challenges you may encounter.

Regards,

AKJ - Your material handling experts

Documents

AKJLexLab Coal Test Report - AKJ · PDF fileThe harder the coal, the less fines the handling process ... control testing on the material at ... increases in surface moisture. The coal