Question

To conduct a proximate analysis of a 100 g sample of waste, you first place it in a 105 °C oven until it reaches a stable weight of 88 g. Next, you place the dry sample into a closed crucible and place it into a 950 °C furnace. After baking, the sample weight is 15 g. Finally, you place the sample into an open crucible and bake it at 950 °C. The sample then weighs 6g.

Calculate the following: Moisture content (% weight, dry basis), Volatile
combustible matter, fixed carbon, and ash content.

Answer 1

The moisture content on a dry basis of the waste sample is 13.64%. The volatile combustible matter is 82.95%, fixed carbon is 10.23%, and ash content is 6.82%, calculated based on the change in weight after heating the sample in various conditions.

Step-by-step explanation:

You asked for help with the following: Calculate the moisture content (on a dry basis), volatile combustible matter, fixed carbon, and ash content for a waste sample, following certain steps with given weights before and after heating processes.

To calculate the moisture content on a dry basis:

• Original sample weight = 100 g
• Weight after drying at 105 °C = 88 g
• Moisture content (dry basis) = (100 g - 88 g) / 88 g × 100 = 13.64%

To find the volatile combustible matter (VCM), fixed carbon, and ash content:

• Weight after heating in a closed crucible at 950 °C = 15 g (loss attributed to VCM)
• Weight after heating in an open crucible at 950 °C = 6 g (final weight, indicating ash content)
• Volatile combustible matter (VCM) = (88 g - 15 g) / 88 g × 100 = 82.95%
• Fixed carbon = (15 g - 6 g) / 88 g × 100 = 10.23%
• Ash content = 6 g / 88 g × 100 = 6.82%

These calculations help in determining the composition of the waste sample by examining the losses at different treatments: drying, combustion, and ashing.