1.Primary air is used for transportation of fine coal particle from coal mill to boiler floor at different elevations as per requirement.
2.Primary air is used for preheating of moisturised coal in to the coal mill so that minimum energy is required for combustion of the same.
3.As we all know that only 23% oxygen is available in the air by weight. For combustion of huge quantity of coal inside the boiler very high quantity of oxygen is required. This oxygen requirement will be completed by secondary air which is supplied by FORCED DRAFT fans through ducts.
This secondary air is coming via air preheater hence its outlet temperature increases this will help in combustion and low heat input is required for combustion of coal.
Boiler efficiency is mainly depended on the amount of losses in the system. In high capacity pulverized coal fired boilers the total losses account to about 12 to 14%. Roughly 50% of the losses are governed by fuel properties like hydrogen in fuel, moisture in fuel and ambient air conditions. The other 50% losses are carbon loss and dry gas loss. The best efficiency in the boiler can be achieved if the losses are kept to the minimum. Since 50% of the losses are dependent on the fuel and ambient condition, the best efficiency can be achieved by properly tuning the other 50%, i.e. mainly carbon loss and dry gas loss.
The inlet gas pressure is different for different capacity boiler, for example, the pressure for 2 ton steam capacity boiler is about 8~10KPa, while for 4 ton steam capacity boiler is about 12~25KPa. You can tell us the boiler capacity you want, we will help you to get the gas inlet pressure.
When the oil temperature rises to a certain temperature that the oil and gas molecules on the surface of the oil tend to saturate, can catch fire and maintain continuous combustion for a duration of not less than 5S. The temperature is called ignition point.
Four factors are related to the failure of the draft fan of the biomass-fired boiler. The factors are electric, electrical motors, dampers and induced draft fans. Therefore, if the draft fan breaks down, you can check the electric and electrical motor first, then you can check the damper and the induced fan.
Maintenance of the burner: thoroughly clean the rotor plate, ignition device, filter, oil pump, motor and impeller system, and add lubricant to the connecting rod device of air valve. Retest the combustion condition.
1. Sufficient furnace temperature: Sufficient fuel combustion of biomass-fired boilers firstly requires high furnace temperature. The temperature should meet the requirements of sufficient fuel combustion. Besides, the combustion speed is required to be proportional to the temperature. Moreover, the furnace temperature should be raised as much as possible on the premise that slag is not formed in the furnace.
The gas consumption of 10 tph gas-fired boiler is related to technical parameters.
Such as heating surface layout, heat preservation effect, heat loss, water capacity, etc. The calculation formula of gas consumption of 10 tph gas-fired boiler is as follows:
=10 tph gas-fired boiler output÷ thermal efficiency ÷calorific value of natural gas
= 6,000,000 kcal ÷ 0.98 ÷ 8,600 kcal / h = 712 m3
Therefore, the gas consumption of 10 tph gas-fired boiler is 712 m3/ h
The gas consumption of the above gas-fired boiler is calculated at full capacity. In practice, the gas consumption changes with the operation load and operation conditions. In addition, if thermal efficiency of the gas-fired boiler is different, the gas consumption is different, too. The higher thermal efficiency is, the lower gas consumption is.
