This paper examines a coal-water slurry containing petrochemicals (CWSP) based on lignite, bituminous coal, anthracite, and typical waste - carbon residue obtained from the pyrolysis of tires. Waste motor oil is used as a liquid fuel component of the slurry. The study of CWSP ignition is performed via placing a fuel droplet on a low-inertia thermocouple junction (junction diameter is 0.1 mm; thermal inertia is less than 1 s) into the hot oxidant flow. The temperature and velocity of the oxidant flow vary in the range of 600-1200 K and 0.5-5 m/s, respectively. These ranges are typical for power plants in the large- and small-scale energy industry. The paper specifies the minimum oxidant temperatures which are sufficient for sustainable ignition, as well as the ignition delay times, the times for complete burnout of CWSP droplets (radii of 0.5-2 mm), and the maximum temperatures in the fuel combustion area. We discuss how the oxidant temperature and the component composition of CWSP influence the parameters listed above. Addition of a small amount of coal (with high content of volatiles) in a fuel composition can decrease the ignition temperature of CWSP based on bituminous coal and even anthracite by 50-150 K compared to that which is a traditional one for the energy sector. At the same time, the presence of coal of a high degree of metamorphism in CWSP leads to a substantial increase in the temperature in the fuel combustion zone, as well as in the duration of this process (as a result, more heat is released). The paper indicates the compositions which are characterized by minimum ignition lag, low temperature of ignition, and relatively high temperatures of combustion.
ASJC Scopus subject areas
- Chemical Engineering(all)
- Fuel Technology
- Energy Engineering and Power Technology