Heating oil is made from diesel fractions of straight-run distillation and distillates of catalytic and thermal cracking.
It differs from conventional diesel fuel by viscosity and fractional composition. Diesel fuel is lighter.
To meet all industrial requirements, special depressant additives must be added to heating oil. This step helps to improve its performance. In particular, we are talking about the freezing point (-28°C) and ignition point (40°C). Heating oil does not have the pungent smell, which is characteristic of many other oil products.
Heating oil is transported in special tanks equipped with a discharge valve as well as air exhaust and pressure control valves. Small batches can be transported in canisters made of plastics or metal.
Dark heating oil is widely used for heating of residential buildings (low-power heating systems) and in generators of average power.
Quality heating oil should have the following characteristics:
- Kinematic viscosity of not more than 8 mm2/s at 20°C.
- Flash point in closed crucible should not be less than 45°C.
- Sulfur content of not more than 0.5% for low-sulfur fuels, and 1.1% for sulfur fuels.
- Acidity of not more than 5 mg KOH per 100 cm3.
- Ash content of not more than 0.02%.
- 10%-residue coking of not more than 0.35%.
- Density, cloud point, cetane number and iodine number are not regulated.
The color of dark heating oil is usually black, brown or light brown. It may have traces of water. Samples of this oil product must stand the copper plate tests.
Demand for heating oil is high due to its good calorific value. If there is no way to use gas for heating or there’s a lack of finance for purchasing expensive diesel fuel, heating oil can solve the problem.