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. If there is air in the pump or suction pipe, the air should be discharged.
2. If the depth of the bottom valve immersed in the water is not deep enough, the depth should be increased.
3. If the rotational speed is too slow or the conveyor belt is too loose, the rotational speed should be adjusted and the conveyor belt should be tightened.
4. If the impeller, suction pipe and bottom valve are blocked by dirt, you should check the pump body and clean the dirt.
5. If the height of water conveyance exceeds the regulations too much, the pump head should be adjusted to the specified range.
The temperature of flue gas generated by a biomass-fired boiler is relatively high. But it is not corrosive. So, it is suitable to use heat resisting glass fiber needled felt bag which has a good use effect. Moreover, this kind of cloth bag is not very expensive.
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.
The term “boiler efficiency” is often substituted for thermal efficiency or fuel-to-steam efficiency. When the term “boiler efficiency” is used, it is important to know which type of efficiency is being represented. Why? Because thermal efficiency, which does not account for radiation and convection losses, is not an indication of the true boiler efficiency. Fuelto-steam efficiency, which does account for radiation and convection losses, is a true indication of overall boiler efficiency. The term “boiler efficiency” should be defined by the boiler manufacturer before it is used in any economic evaluation.
A process load is usually a high-pressure steam load. A process load pertains to manufacturing operations, where heat from steam or hot water is used in the process. A process load is further defined as either continuous or batch. In a continuous load, the demand is fairly constant - such as in a heating load. The batch load is characterized by short-term demands. The batch load is a key issue when selecting equipment, because a batch-type process load can have a very large instantaneous demand that can be several times larger than the rating of the boiler. For example, based on its size, a heating coil can consume a large amount of steam simply to fill and pressurize the coil. When designing a boiler room for a process load with instantaneous demand, a more careful boiler selection process should take place.
The number of passes that the flue gas travels before exiting the boiler has been a good criterion when comparing boilers. As the flue gas travels through the boiler it cools, and therefore changes volume. Multiple pass boilers increase efficiency because the passes are designed to maximize flue gas velocities as the flue gas cools. ZOZEN has developed new design technologies in our WNS series boilers allowing for comparable efficiencies in fewer passes, resulting in smaller boiler systems that will fit in tighter quarters.
Stack temperature is the temperature of the combustion gases (dry and water vapor) leaving the boiler. A well-designed boiler removes as much heat as possible from the combustion gases. Thus, lower stack temperature represents more effective heat transfer and lower heat loss up the stack. The stack temperature reflects the energy that did not transfer from the fuel to steam or hot water. Stack temperature is a visible indicator of boiler efficiency. Any time efficiency is guaranteed, predicted stack temperatures should be verified.
Stack loss is a measure of the amount of heat carried away by dry flue gases (unused heat) and the moisture loss (product of combustion), based on the fuel analysis of the specific fuel being used, moisture in the combustion air, etc.
