Automotive Diesel Oil and Heating Oil

Question 1

In France, what is the sulfur spec for HHO ?

Answer 1

1000 ppm

Question 2

What is the problem with n-paraffins in Diesel ?

Answer 2

Very good combustion properties but low resistance to low temperatures

Question 3

In N-paraffins, what is the link between carbon chain lenght and cristallization temperature ?

Answer 3

The longer the chain, the higher the cristallization temperature = the worst the resistance to low temperatures

Question 4

What are the three measurements used to characterize a diesel cold flow properties ?

Answer 4

• Cloud point
• Cold Filter Plugging Point (CFPP)
• Pour point (not for ADO anymore)

Question 5

What is the cloud point ?

Answer 5

The temperature at which a cloud appears in the test tube

Question 6

What is the pour point ?

Answer 6

The temperature at which the product can no longer flow if the test tube is tilted for 5s

Question 7

What are the cloud point specs for ADO ?

Answer 7

From October to March : -5°C

From April to September : +5°C

Question 8

What are the specification for cloud and pour point of HHO ?

Answer 8

• Cloud Point : +2°C

- Pour Point : -9°C

Question 9

What are the specs for CFPP for ADO?

Answer 9

From October to March : -15°C

From Qpril to September : 0°C

Question 10

How can we improve cold flow properties of ADO ?

Answer 10

• change formulation (incorporate lighter HC like kerosene cut, nahthenes or aromatics) but negative effect on comubstion quality
• Additives like anti-settling additives (WASA)

Question 11

What is the cetane number ?

Answer 11

The cetane number measure the ability of ADO or HHO to auto-ignite. The higher the cetane number, the shorter the ignition delay

Question 12

Which family of components has the best cetane number ?

Answer 12

N-paraffins have a good cetane number

Question 13

How is the cetane number measured ?

Answer 13

Cetane number is measure with a Diesel CFR engine and comparison with 2 references

Question 14

What are the two references to measure cetane number ?

Answer 14

Good reference : nC16

Bad reference : hepta-methylnonane

Question 15

How is the calculated cetane number estimated ?

Answer 15

Volatility (ASTM distillation) and chemical composition (density) are taken into account

Question 16

What are the specifications for cetane number ?

Answer 16

• ADO : measured = 51 and calculated = 46

- HHO : measured = 40

Question 17

Why are measured and calculated cetane number sometimes very different?

Answer 17

Because of the additives added in small quantities : measured effect on the CFR engine but too small quantities to impact calculated value

Question 18

What are the ASTM distillation specs for ADO ?

Answer 18

• max 65% distilled at 250°C
• max 85% distilled at 350°C
• max 360 °C at 95% distilled

Question 19

What is the spec for density of ADO ?

Answer 19

820 < d < 845 kg/m3 at 15°C

Question 20

What is the spec for viscosity of ADO ?

Answer 20

2 < viscosity < 4.5 cSt at 40°C

Question 21

Why are nitrogen impurities a problem for ADO ?

Answer 21

Some nitrogen compounds are gum precursors

Question 22

Why is water a problem in ADO ?

Answer 22

It can damage the injection pump and the injectors and to reduce the risk of bacterial contamination

Question 23

What is the spec for water content in ADO ?

Answer 23

200 mg/kg

Question 24

What new problem arrived with low sulfur content in ADO ?

Answer 24

Low sulfur content means poor lubricating power of ADO

Question 25

Which component is added to improve lubricating power lost by deep desulfurization ?

Answer 25

1-2% of vegetal oil ester

Question 26

What is the flash point ?

Answer 26

The flash point is the minimum temperature at which fuel emits enough vapor to inflame in presence of an ignition source

Question 27

What are the flash point specs for ADO and HHO ?

Answer 27

55 < flash point < 120 °C

Question 28

Why do we have to control electrical conductivity of ADO ?

Answer 28

Because it facilitates the elimination of electrostatic charges created during transfer and enable to avoid any risk of inflammation

Question 29

What is the spec for electrical conductivity in ADO ?

Answer 29

Min 150 pS/m at 20°C

Question 30

What is the spec regarding sulfur content in ADO ?

Answer 30

Max 10 ppm

Question 31

Why was a spec on sulfur content added and why so low ?

Answer 31

To protect catalytic converters used in modern vehicles

Question 32

What are the pollutents contained in exhaust gas ?

Answer 32

CO2, SO2, CO, NOx, unburnt HC and particles

Question 33

Why is polyaromatic content monitored in ADO ?

Answer 33

Because PAH are precursors for particles

Question 34

What is the spec for PAH content in ADO ?

Answer 34

PAH content is now limited to max 8%

Question 35

What are the two technologies which enable to meet the new specs for low NOx emissions ?

Answer 35

• Selective Catalytic Reduction (Adblue)

- Exhaust Gas Recycling (cheaper)

Question 36

What are the biofuels used in ADO ?

Answer 36

Fatty Acid Methyl Ester (FAME)

Question 37

What is the best oleaginous plant for FAME in ADO ?

Answer 37

Rape seed

Question 38

What are the two problems with FAME ?

Answer 38

• Poor chemical stability

- Poor low temperature performance

Question 39

What are the possibles bases for ADO and HHO ?

Answer 39

• LGO / HGO from atmospheric distillation
• LVGO from vacuum distillation
• Kerosene cut (cold flow properties)
• Distillate hydrocracking (high cetane + good stability)
• LCO from FCC
• Gas oil from visbreaking
• Oxygenated compounds