Standard Test For Ash From Petroleum Products , D482 Ash contents is defined as the inorganic residue that remains after combustion of the oil in air at specific high temperature. Ash ranges from 0.1% to 0.2%. The ash content of a fuel is a measure of the amount of inorganic noncombustible material it contains. Some of the ash forming constituents occur naturally in crude oil: others are present as a result of refining or contamination during storage or distribution. For instance, it could be due to the presence of compounds of the following elements: vanadium, sodium, calcium, magnesium, zinc, lead, iron, nickel. Or it could be picked up by the crude oil during storage and handling. Metals content above 200 ppm are considered to be significant but the variations are very large. The higher the ash content the higher is the tendency of the crude oil to form sludge or sediment. Oils containing more than 0.05% ash are considered high ash oils; those containing less than 0.02% ash are considered low ash oils. Prepared By Yasir Albeatiy

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University of Zakho
Faculty of Engineering
Department of Petroleum Engineering
2014-2015
Name of Student: Yasir Ammar Ahmed
Class 2 / 2nd
stage
Experiment NO. 7
Standard Test For Ash From Petroleum Products , D482
Experiment contacted on: 12/1/2015
Report submitted on: 19/1/2014

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Contents
1.1 Objectives -------------------------------------------------------- Page 3
1.2 Introduction ------------------------------------------------------ Page 3
1.3 Apparatus and Materials ---------------------------------------- Page 4
1.4 Procedure --------------------------------------------------------- Page 5
1.5 Result and Calculations -----------------------------------------Page 5
1.6 Discussion --------------------------------------------------------Page 6
1.7 Conclusion --------------------------------------------------------Page 8
Figure(1): Apparatus and Materials used in this experiment --------------- Page 4
Figure(2):Pendant superheater slag with corrosion product underneath. – Page 6
Figure(3): Treatment can make deposits friable for easy removal ----------Page 7
Table (1): Typical residual oil analyses ----------------------------------------Page 8

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Standard Test For Ash From Petroleum Products ,
D482
1.1 Objectives
To determine the ash content of a sample of Residue Crude Oil (RC).
1.2 Introduction
Ash contents is defined as the inorganic residue that remains after combustion of the
oil in air at specific high temperature. Ash ranges from 0.1% to 0.2%. The ash
content of a fuel is a measure of the amount of inorganic noncombustible material it
contains. Some of the ash forming constituents occur naturally in crude oil: others are
present as a result of refining or contamination during storage or distribution. For
instance, it could be due to the presence of compounds of the following elements:
vanadium, sodium, calcium, magnesium, zinc, lead, iron, nickel. Or it could be
picked up by the crude oil during storage and handling. Metals content above 200
ppm are considered to be significant but the variations are very large. The higher the
ash content the higher is the tendency of the crude oil to form sludge or sediment.
Oils containing more than 0.05% ash are considered high ash oils; those containing
less than 0.02% ash are considered low ash oils.
Knowledge of the amount of ash-forming material present in a product can provide
information as to whether or not the product is suitable for use in a suitable
application. Ash can result from oil or water-soluble metallic compounds or from
extraneous soldier such as dirt and rust.
Refining crude oil that contain high value of ash content leading to deposition of the
metals (in any form) on to the catalyst leads to catalyst deactivation whether it be by
physical blockage of the pores or destruction of reactive sites. In the present context,
the metals must first be removed if erroneously high carbon residue data are to be
avoided.
Since most of the ash in heavy fuels occurs naturally, it usually is difficult for the
refiner to remove it economically. Purchasing different crude oils with lower ash
content can be very expensive. Therefore, methods have been developed for
counteracting the effects of ash. These include the use of additives, modifications in
equipment design, and the application of fuel processing methods such as water
washing.

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1.3 Apparatus and Materials
1. Crucible.
2. Stand.
3. Source of flame (heat).
4. Sample of residue crude (RC).
5. Scientific Balance.
6. .
Stand Source of flame (heat) Scientific Balance
Crucible Residue Crude (RC) Furnace
Figure(1): Apparatus and Materials used in this experiment

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1.4 Procedure
1. First of all we took a dry clean crucible and weight it with the scientific
balance.
2. Record the weight of empty crucible which will be W1 .
3. Add 2 g of the sample (RC) to the crucible.
4. Record the weight of sample (RC) which will be W2 .
5. Put the crucible contain the sample on the stand and then poke the fire in
the burner under the crucible and heat it carefully at such temperature that
the sample continues to burn at a uniform and moderate rate leaving only
carbonaceous residue wen the burning ceases.
6. Heat the residue at muffle furnace at 775 + 25 o
C until all carbonaceous
materials has disappeared ( 20 -30 mins).
7. Cool the crucible at room temperature in a suitable container.
8. Weigh the crucible this will be W3 .
1.5 Result and Calculations
Weight of empty crucible, W1 = 17.9 g
Weight of the test specimen, W2 = 2 g
Weight of ash and crucible, W3 = 17.92 g
To calculate the ash content of residue crude, we use this equation below:
𝑨𝒔𝒉 , 𝒎𝒂𝒔𝒔 % =
𝑾𝟑 − 𝑾𝟏
𝑾𝟐
× 𝟏𝟎𝟎
Where:
W3 – W1 = mass of ash in grams
W2 = mass of sample in grams
𝐴𝑠ℎ , 𝑚𝑎𝑠𝑠 % =
17.92 − 17.9
2
× 100 = 1%

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1.6 Discussion
1. What is the problems of combustion of oils with high ash content?
The combustion of high ash oils produced troublesome deposits on boiler convection
surfaces such as steam generating, superheat, reheat, and economizer sections. The
firing of high ash oils (even in those units which were originally designed to burn
coal) produced convection surface deposition that was difficult to remove by soot
blowing. The deposition of ashes problems is divided into two main problems:
a. Slagging refers to deposits formed on sections of the boiler exposed mainly
to radiant heat, such as the furnace walls. Slagging deposits are formed
from molten or half molten ash particles that stick to the hot furnace walls.
They are not formed immediately upon firing up the boiler but accumulate
slowly after an initial layer has been formed over the walls.
b. Fouling is used to characterize the deposits formed on the convective pass,
such as the heat exchanger tubes. In this case, deposits are formed by
inorganic vapours that condense on the relatively cooler surfaces of the heat
exchanger tubes. Although the mechanisms of formation for slagging and
fouling are not the same, both are closely linked with the tendency of the
fuel ash components to melt or vaporize at low temperatures.
Figure(2):Pendant superheater slag with corrosion product underneath.

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2. How you can decrease the ass formation in fuel combustion?
Additives are used to control fouling by elevating the melting point of the
deposits, by physically diluting deposits, or by providing a shear plane to assist in
removal by soot blowing. Additives used to control fouling contain magnesium,
silica, manganese, and/or aluminum.
The melting point of untreated ash constituents can be as low as 1000°F. The
introduction of appropriate metal oxides elevates the melting point of ash
components by several hundred degrees. The additive components most
commonly used to raise the deposit melting point are magnesium and/or
aluminum. Dosages depend on ash levels in the fuel and the ratio of various ash
components. When melting temperatures are raised, the physical characteristics of
the deposits are altered. Often, the heaviest deposition occurs in areas where the
gas temperature is lower than the melting temperature of a deposit. Therefore, a
treatment program designed solely to elevate the melting point of the deposit will
not solve the problem, and it is necessary to introduce additive components that
change the physical characteristics of the deposit, making it more friable.
Additives used for this purpose contain compounds of magnesium or aluminum.
Aluminum is usually the most effective material for increasing friability of
deposits.
Figure(3): Treatment can make deposits friable for easy removal.
Also removing salts in crude oil before its exposed to distillation process can paly
a role in decreasing the ash contents in crude oil and its products. Since the ash
forming materials derived from metallic salts and organometallic compounds,
reducing the salt in crude oil will decrease the ash content as well, for this
purpose a de-salter unit is placed before the distillation tower wash the crude oil
with sweet water to remove the metallic salts in it.

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3. What is the relation between the sulfur content and ash
content in reside crude oil? Why ?
Table (1.1): Typical residual oil analyses.
From the table Sulfur emission regulations have severely restricted the use of high
sulfur oils. Generally, high sulfur oils (greater than 1.0% sulfur) have high ash
contents. Because sulfur compound will make new compounds with other materials
which will solidify at specific temperature in the boilers that result the high ash
contents of RC that contain high ratio of sulfur. These oils are usually imported from
the Caribbean area. Prior to 1972, most East Coast boilers were burning high sulfur,
high ash oils.
4. Why light fractions of petroleum products have negligible ash
content?
Light fractions don’t contain metallic salt and organometallic compounds as well
as the combustion temperature of light fractions is low compare with the
temperature that form the ashes.
1.7 Conclusions
1. The principal elements contributing to high ash contents of petroleum residual
stocks and the cokes obtained from these stocks are sodium, iron, and
magnesium, the contents of which increase with increasing content of chlorides
in the crude oil.
2. The contents of silicon, nickel, vanadium, and manganese in the residual stocks
and in the cokes are essentially independent of the salt content of the crude oil.
3. Thorough desalting of crude oil is a basic prerequisite in the production of low-
ash cokes.
4. In order to produce low-vanadium coke, the coker feedstock must be selected
very carefully.
Characteristic High Ash Medium Ash Low Ash
Specific Gravity, at 60 °F 0.9548 0.9944 0.9285
Viscosity SSF at 122 °F, sec 240 200 100.5
Calorific Value, Btu/gal 147,690 152,220 147,894
Bottom Sediment & Water,
%
0.1 0.4 0.1
Sulfur, % 1.93 2.26 0.62
Ash, % 0.06 0.04 0.02
Vanadium, ppm 363 70 6
Sodium, ppm 16 50 9
Nickel, ppm 48 19 14
Aluminum, ppm 9 1 10
Iron, ppm 12 3 1