APPROACH FOR ADULTERATION DETECTION

8.0 APPROACH FOR ADULTERATION DETECTION

A number of analytical techniques are available to detect adulteration. In all cases described below, it is important to have good sampling technique and access to a good petroleum analytical laboratory. For the majority of the tests, accurate data and analysis of original or uncontaminated fuel are also pre- requisite. Some of the approaches for detecting adulteration are outlined below:

(i) Full specification tests of the standards:

This may be quite time consuming and many parameters may be well within the requirements even if the fuel is adulterated. In fact fuel standards or specifications are framed to ensure that the fuel corresponds to certain level of quality commensurate to technology requirements of the vehicles. Parameters in the fuel standards may not necessarily stand as checkpoint for any sort of fuel adulteration.

(ii) Testing selected parameters:

This asks for testing some critical parameters, which are likely to be affected or altered by adulteration and adversely affect engine performance and emissions and can be evaluated. Lists of such parameters are given below in Table 3 &4. In general, many of the selected parameters may already be included in the full specification standards. However, dosage of multifunctional additive and cetane improver are intended for following the adulterants by dilution. However, convenient methodology for determination at refinery and outlet levels are yet to be lined up in the country.

Table-4: Selected Parameters for Diesel Testing

1. Flash Point
2. Density
3. Distillation
4. Sulphur
5. Polycyclic aromatics (+2 rings)
6. Total sediment
7. Cetane number
8. Cetane index
9. Multifunctional additives-dosage
10.Cetaneimprover-presence,

dosage: For diesel fuel without cetane improver, cetane index can be utilized. If dosage can be determined, it may be used for detection of adulteration based on depletion from original dosage.

(iii) Testing methods:

There can be several alternate approaches, some prominent approaches are:

» Use of conventional manual petroleum testing methods.

» Utilization of automated instruments for conventional petroleum testing. For example- gas chromatographic method is used for simulated distillation. A number of instrumental analysis methods have been developed for establishment of parameters of fuels.

(iv) Emerging instruments for fuel surveillance:

Several new instruments are available which claimed to carry out instrumental analysis for the estimation of key parameters of transport fuel. For example the following may be noted.

(a) Accurate and comprehensive fuel analyzer. The portable FOxFTIR fuel analyzer is claimed to be ideal for the analysis of commercial fuels.

(b) ZeltexZX101CC Portable Octane analyzer.

(v) Use of marker:

Various markers can be used to identify adulteration, such as kerosene in gasoline. Earlier kerosene was used as major adulterant for adulteration in gasoline and diesel fuel. For detection of adulteration of fuels with kerosene a blue dye and furfural were used. However, where visible dyes have been applied in South Asia, they have not been effective. It is believed that presently the range of adulterants has widened. Various chemical/biochemical markers are available in market e.g. Spectrace marker by Mortan international, petro markers by M/S GFI, Biocode markers by M/S Biocode ltd., etc. The marker is added in trace level with the fuel and whenever the product is to be tested, the marked chemical is detected and measured by specific instruments/ immunoassay. This detection test can also be easily carried out in field with equal accuracy as laboratory tests.

Properties of Markers

» They should be miscible with fuels
» Detectable by simple test procedures
» Difficult to remove from marked fuels
» Non-reactive with other fuel additives
» No interaction with material of construction and fuel impurities; and
» Should be cost effective

Limitations of Marker System

» Relatively a high cost option
» Difficult to maintain a constant dosage at low concentration
» May be leached out by water in the product tanks
» May interact with materials and fuel impurities

8.1 Key Issues Related to Adulteration Detection

There are several issues related to detection of fuel adulteration. A very sound system of fuel quality monitoring and surveillance is a pre-requisite to launch an adulteration detection programme. Institutions involved in the programme should have access to state of the art fuel testing laboratories and sample storage and handling facilities. Some of the key issues are described below:

1. Monitoring the quality and frequency:

To check adulteration a system of monitoring is suggested whereby fuel samples will be collected from atleast 10 % of the fuel dispensing stations in a week. In this way all fuel stations will be covered in a period of three months. At one time three samples will be collected and sealed jointly by collecting and dispensing station.

2. Agency for collection of samples and co-ordination:

Since consumer interest is the prime objective of the quality surveillance program, consumer representatives groups should be involved in the process. The following organizations should be explored to take up the sample collection and surveillance activity.

(a) Society of Automobile Manufacturers (SIAM)
(b) Consumer forum
(c) NGOs interested in the field
(d) Representative from the local Transport Authority
(e) Civil Supplies Department
(f) Bureau of Standards; and
(g) Pollution Control Boards/Agencies

Moreover any quality conscious consumer may collect and get the fuel samples tested for quality assurance as and when he desires.

3. Testing laboratories:

In different cities the following possibilities should be explored

- Independent Government funded test laboratory to be managed under a society.
- Government test laboratory
- Private existing laboratory to be reinforced.
- Private new laboratory
- New laboratory to be set up in academic institute premises for the purpose.

There should be system of accreditation, periodic checking of quality for analysis by round -robin test and also withdrawing accreditation in case of consistent out-off-line performance in round -robin tests.

4. Sample collection, handling and storage:

The different aspects of sample collection, handling and storage including type of sample collector, need for inert gas blanketing etc. may be investigated and prescribed in a standard to improve the reliability of the monitoring process.

5. Product data sheet:

To facilitate subsequent analysis it is suggested that a product is also accompanied by a data sheet of analysis as it leaves the refinery or marketing installation in particular the item of short test based on tests on the dispatched product.

6. Handling failure samples:

In case of first failure, after identifying the source of contamination the controlling officer of the oil companies will take appropriate action for the group responsible for adulteration. The penalized person will have the possibility to appeal to the supervisor of the controlling officer in first case. The supervisor may review the case and dispose off the appeal keeping the samples collecting authority informed. Similarly an appealing point is to be conceived for repeated failure cases. However, the present practice of penalizing the dealer and Oil Company being the judge is not yielding the desired results. Other practices include the practice in line with that of Australia, wherever the outlet belongs to a company, the quality aspects of that outlet is the sole responsibility of the parent oil company supplying the product and in case of any failure the company is penalized.

7. Disposal of spent sample:

If it is a pass sample it can be sent back to the pump through the Oil Company. The failed sample will be collected and returned to oil companies.

8. Funding the cost of fuel quality surveillance:

Charging a small tax either at the dispensing outlet or at the refinery outlet can cover the cost of fuel quality surveillance.

9. Annual market product quality survey:

Analogous to Octel, Ethyl and Parammins worldwide survey of fuel qualities transport fuel quality survey for summer and winter periods, covering at least 50 samples collected all over the country should be carried out.