Comparative calculation of the economic effect of pyrolysis / direct combustion of fuel briquettes

For example, let’s take Piny-kay briquettes (or any other wood briquettes) and charcoal briquettes obtained by pyrolysis of a wood briquette.
Let’s compare the economic benefit from direct combustion of raw materials – wood briquette and combustion of charcoal briquette produced in the pyrolysis process from Piny-kay briquette.

The calculation of the economic effect was carried out:
– all calculations are based on available heat;
– RAW MATERIALS: Piny-kay briquette;
– taking into account the same efficiency of equipment used in the combustion or pyrolysis of raw materials;
– without taking into account the different calorific value of gaseous products obtained by direct
incineration or pyrolysis;
– excluding the wages of the service personnel;
– excluding depreciation, operating and other deductions;

1. Characteristics of Piny-kay wood briquette:
A) Caloric content 4500 kcal / kg
B) Ash content up to 3%
B) Humidity up to 5%
2. Characteristics of the obtained charcoal briquettes:
A) Caloric content 7500 kcal / kg
B) Ash content up to 3%
B) Humidity up to 5%

MORE DETAILS: about ecological plants for the production of charcoal briquettes: Equipment for the production of charcoal
3. Percentage yield of charcoal briquette: 35% ( content carbon 82%)
4. Received amount of heat from a ton of raw materials:
A) With direct combustion: 4500000 kcal
B) When burning gaseous and liquid pyrolysis products:
      4,500,000 – (7,500,000 * 35%) = 1,875,000 kcal
Where 7,500,000 * 35% = 2,625,000 kcal is the available heat contained in charcoal briquettes produced from 1 ton of pini-kay briquette, which is 58% of the calorie content of the briquette.
5. Average annual price of raw materials in Ukraine: 2500 UAH / t (including delivery)
6. An increase in the consumption of raw materials to obtain the same 4,500,000 kcal of thermal energy at
pyrolysis will be: 48% = 0.58 tons or in monetary terms 1 450 UAH.
7. The output of charcoal briquettes will be: 0.58 * 35% = 0.203 tons.
8. That is to obtain 4,500,000 kcal of thermal energy, which corresponds to 1 ton of raw materials with direct
burning will consume:
      1 + 0.58 = 1.58 tons of pini-kay briquette in the amount of 2500 * 1.58 = 3950 UAH.
9. Output of charcoal briquette from used raw materials to obtain 4 500 000 kcal of thermal
energy, will be: (1 * 35%) + (0.58 * 35%) = 0.553 t.
10. Average annual price of coal briquettes in Ukraine: UAH 14,000 / t
11. Profit from the sale of charcoal briquettes: 14,000 (UAH) * 0.553 (t) = 7,742 UAH.
12. The economic effect (profit) during pyrolysis of the pini-kay briquette will be:
      7 742 (UAH) – 3 950 (UAH) = 3 792 UAH. and 4 500 000 kcal of heat received

Those the resulting profit from the sale of charcoal briquettes during pyrolysis of 1.58 tons of Piny-kay briquette will amount to UAH        3,792 and 4,500,000 kcal of thermal energy.
At the moment, the production of fuel briquettes from wood waste is becoming more widespread throughout the world, as it contributes to the preservation of forests and profit from production waste. Briquettes are compressed waste from wood processing plants (shavings, sawdust, wood chips). At the same time, a product is supplied to the market that has a number of advantages in combustion and heating in comparison with other types of fuel.
So, 1 tone of fuel briquettes can replace:
1 ton of briquette = 5 cubic meters of firewood;
1 ton of briquette = 480 cubic meters of gas;
1 ton of briquette = 700 liters of fuel oil;
1 ton of briquette = 500 liters of diesel fuel.

It should be noted that the moisture content of the briquette is 8.5%, while the moisture content of wood can vary from 30 to 65%. Thus, there is no need to use pre-drying when carbonizing the briquette.
Let’s list the main benefits of burning charcoal briquettes, thanks to which they are gaining more and more popularity:

  • long burning time, about 6 hours. High class briquettes can burn for more than 6 hours.
  • low ash content of fuel briquettes. Not more than 0.5 – 1.0%. When it burns, it is not coals, but ash that remains;
  • briquettes can be used several times. It is necessary to extinguish them, then, if necessary, rekindle;
  • retention of shape throughout the entire burning time, high strength of the briquette;
  • briquettes have the ability to burn simultaneously throughout the volume, both outside and inside, due to the presence of an internal hole;
  • no acrid smoke and flame;
  • constant combustion temperature.