PROXIMATE ANALYSIS OF COAL

ABSTRACT

This report is written to account for the experiment carried out on the proximate analysis of a naturally occurring coal from Enugu state and a coal made from wood in the absence of air.

The outcomes of this experiment are they moisture content, ash content and volatile matters contains in each of the given samples of coal. The values were determined in percentage and the experiment shows that the algebraic sum of the weight percent of moisture content, ash content and volatile matter is ….%. This was achieved using a 3g weight coal powder.

INTRODUCTION

Proximate analysis has long been used to determine the rank of coals by separating volatile components, fixed carbon and inert components. Because of the wide ranging quality of coal products and the commercial value of ranking these products the need for good methods is obvious.

It is well known that when coal is heated out of contact with air it decomposes as volatile matter (such as hydrocarbon gases, hydrogen, tar, ammonia moisture etc.).

The compositions in the coal contributes greatly to its properties meanwhile, moisture content in coal may accidental or may be due to the its hydgroscopic properties. Unlike the ask content which has been traced back to the origin of the coal (i.e plant of shale).

However, volatile matter content governs largely, the characteristics of the combustion and it determines the suitability of a coal for special purposes.

In this case, and over the year proximate analysis has been the most accurate and simplest method of classifying coal.

PROCEDURE

The following are the procedures for the experiment:

1.      At first the moisture content was determined as followed:

2.      3g of powdered coal was weighed accurately into a petri dish and spread evenly over the surface.

3.      The sample was then dried in oven at a temperature of 110^OC for an hour.

4.      After this time, the sample was removed from the oven and allowed to cool in a desiccator before weighing.

5.      The inherent moisture content was then calculated from the loss in weight.

6.      Following after this was the determination of the ask content:

7.      1g of the coal was weighed in a silica tray 7x4x1cm in dimension.

8.      The sample was heated slowly in a muffle furnace to prevent mechanical loss  at a temperature well around 800^OC, holding at this temperature for an hour.

9.      After this, the sample was removed from the furnace and allowed to cool in a desiccator, after which it was weighed.

10. The ash was noticed to have red colour. Hence it can form clinker.

11.  Finally, volatile matter determination followed:

12. 1g of coal was weighed in a porcelain crucible having a capacity of 30ml

13. The crucible was closed with a well-fitting lid and was suspended in a silica tray

14. The heating followed in a muffle furnace for 7 minutes at a temperature of 980^OC.

15. The resulting product was allowed to cool in a desiccator and then weighed.

DATA AND RESULTS

Table1: moisture content.

Weight	Enugu Coal	Ordinary Coal
Weight of the crucible	147.98	7.460
Weight before heating	150.98	10.46
Weight after heating	150.76	10.30
Mass of the water	000.22	0.160

From the results obtained from the other groups A, B, and C, there masses for water in Enugu and Ordinary coal are:

for Enugu coal; 0.17, 0.20 and 0.29

for ordinary coal; 0.18, 0.17, 0.18

Therefore upon cooperation, the average weight for coal can be estimated as:

Average weight of Enugu coal =  

Average weight of ordinary coal =

Therefore, the moisture content of the coal is:

Moisture content of Enugu coal =

Moisture content of ordinary coal =

Table 2: Ash content

Weight	Enugu coal	Ordinary coal
Weight of the crucible		147.98
Weight before heating		148.98
Weight after heating		148.12
Weight of the ash		0.86

When compared with the other groups, the average ash weight for ordinary coal is:

Average weight for ordinary coal =

Therefore the ash content for the ordinary coal is:

Ash content =

Table 3: volatile matter.

Weight	Enugu coal	Ordinary coal
Weight of the crucible		142.71
Weight before heating		143.71
Weight after heating		143.21
Weight of the ash		0.50

Average volatile matter =

Weight percentage of  volatile mater =

CONCLUSSIONS

This experiment was carried out successfully for the ordinary coal because the time went against us during the experimentation.

It is however cleared that the moisture content in coal ranges between 5 – 8% depending on its mode of formation.

The ask content of the coal as concluded in this experiment is not less than 85% and the volatile matter content was estimated to be 52.3%.

Hence there will be need to provide a means to minimizing the pollution that might be caused by the fly and bottom ashes during the massive usage of coal.