The coal-fired boiler refers to the boiler uses various types of coal as fuel and converts the heat of coal to steam or hot water.
There are generally two calculation methods of the circulating water volume of a coal-fired hot water boiler. One is to calculate the hourly water volume of one square meter and the other is to calculate the design parameter volume of every ton. As for the make-up water volume of this type of boiler, it is usually calculated as 1% to 3% of its total circulating water.
The proximate analysis of coal is to dry, heat and burn coal samples as required to get the percentage of moisture, volatiles, fixed carbon and ash in the coal and learn about the characteristics of coal combustion.
Coal-fired boilers refer to boilers that use various kinds of coals as fuel and convert the heat value of coals to steam or hot water.
Some specific parameters should be provided to calculate the theoretical coal consumption of a set of 20 tph coal-fired boiler. If the rated steam pressure is 1 MPa, the heat value of coal is 7000 kcal / kg, the boiler inlet water temperature is 20 ° C, and the boiler thermal efficiency is 80%, the daily coal consumption is 50-56 tons.
Volatile matter in coal refers to the components of coal, except for moisture, which are liberated at high temperature in the absence of air. This is usually a mixture of short- and long-chain hydrocarbons, aromatic hydrocarbons and some sulfur. Volatile matter also evaluate the adsorption application of an activated carbon. The volatile matter of coal is determined under rigidly controlled standards. In Australian and British laboratories this involves heating the coal sample to 900 ± 5 °C (1650 ±10 °F) for 7 min. Also as the rank of coal increases the volatile matter decreases (AMK).
1. The fuel volume is 1 / 30 ~ 40 of the raw material volume after molding;
2. The specific gravity is 10-15 times of the raw material, and the moisture content is between 12% and 18% (the moisture content of coal is below 10-15);
3. The net calorific value can reach 3500-4500 kcal (the net calorific value of class II bituminous coal is 3700-4700 kcal / kg);
4. The ash content is less than 10% (the ash content of coal is more than 20%);
5. Volatile matter ≥ 65.62% (volatile matter of class II bituminous coal≥20%).
6. Biomass fuel belongs to renewable clean energy, which is the same as wind energy and solar energy. The biomass fuel is rich in resources, it can ensure the sustainable use of energy.
7. The sulfur content and nitrogen content of biomass fuel are low, the amount of SOx and NOx generated in the combustion process is low.
In the case of a thermal oil heater in a high-temperature operation state, if it encounters an emergency situation of power failure, its correct treatment is:
When the circulating oil pump cannot operate normally due to power failure, the heat transfer oil in the furnace tube will exceed the allowable value in a short time due to the residual heat of the furnace. At this time, the cold oil switching valve should be opened to release the cold oil in the expansion tank. And sent to the oil storage tank. At the same time, wet coal pressure or emergency shutdown is required and needs to be completed within 5 minutes.
In addition, we need to pay attention to not to put the oil in the expansion tank clean, otherwise the system will inhale air and cause problems. An oil level mark can be made on the oil level of the oil storage tank. When the cold oil is replaced, the valve can be closed in time to avoid the expansion of the expansion tank and the oil storage tank.
Boilers are often distinguished by fuels that power them. The kind of fuel makes an essential difference in operating costs and environmental impact, so it’s important to learn about the various types of boiler fuel.
Coal, is a common boiler fuel. It dominates the global energy arena due to its abundance, affordability and wide distribution across the world. The most commonly used coal fuels include anthracite, bituminous coal, sub-bituminous coal, lignite and peat.
(Question Details) Specific Performance:Broken coal is one of the most common failures of the coal feeder. The coal feeder is the lifeline of the boiler. Its normal operation is the basic guarantee for the normal and stable operation of the boiler, because it’s common occurrence that the coal feeder breaks the coal, especially when multiple coal feeders broken coal simultaneously, the improper handling resulting in overheating, explosion, coking, shutdown and other failures. Answer：cause of failure:(1) The particles of fluidized bed boiler fuel are coarse, but the fine particles in the fuel have a large amount of moisture. It is very easy to bond, resulting in the clogging of coal bunker and coal feeder.(2) Coal particles are jammed and squeezed in the coal feeder, causing the coal feeder chain to break.(3) Impurities in coal, such as woven bags and tree blocks, enter the coal feeder, causing coal feeders to jam, blockage, trip and break pins. Troubleshooting:(1) Fluidized Be
