Fuel freezing point is the temperature at which the fuel loses fluidity. It is an important index that indicates the fuel flows at low temperatures. It often refers to the maximum temperature at which the oil surface remains stationary within 1 minute. The higher the fuel freezing point, the lower the low-temperature fluidity. When the oil temperature is below the freezing point, it cannot be transported in the pipeline.
The selection of a burner of the gas-fired thermal oil heater should be determined according to the boiler proper structure and fuel characteristics and in combination with the actual conditions and requirements. In addition, this kind of boiler can adopt a waste heat recovery device to improve thermal efficiency and reduce heat energy loss.
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.
The fineness of pulverized coal is an important indicator to measure the pulverized coal quality.
In terms of combustion, the particle size of pulverized coal is expected to be as small as possible to facilitate the ignition and combustion, reduce the heat loss of incomplete combustion, the amount of air supply and heat loss of exhaust smoke.
In terms of pulverized coal milling, the particle size of pulverized coal is expected to be as coarse as possible to reduce the power consumption and steel consumption. Therefore, when selecting the fineness of pulverized coal, a compromise of the two aspects is taken as the economic fineness.
It shall be determined through combustion adjustment tests according to the fuel properties and the type of pulverizing equipment.
Compared with the price of a traditional coal-fired boiler, the operation cost of a gas-fired boiler is relatively high. So, users need to consider the price and quality before purchasing a boiler. For a gas-fired boiler, the energy-saving performance is more important than the boiler price. One year is enough for a gas-fired boiler with good energy-saving performance to save the extra costs of the boiler proper. And, the gas consumption is an important indicator to measure the energy-saving performance of a boiler.
Although biomass-fired boilers are environment-friendly boiler products, there are also some situations that biomass-fired boilers can’t be used. Main reasons as follows:
Fuel restrictions: The fuels that contain synthetic compounds can’t be used as the fuel of a biomass-fired boiler, such as waste wood furniture, waste paper, production and domestic waste.
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 function of the burner is to send the fuel and air into the furnace constantly, organize the air flow of pulverized coal reasonably and mix them well for rapid and stable ignition and combustion.