Steam carries about 540 Kcal/kg of useful energy whereas hot water and thermal fluid carry much less energy. Steam does not require a pump to transfer the energy. Generally, if the heating temperatures required are <100°C, then hot water can be used and if temperatures >180°C are needed then thermal fluid might be a better choice. For process temperatures between 100°C and 180°C steam is considered a viable option.
1. They are all a heat conversion device. The heat transfer medium they use is different. The water used in the steam boiler is heated to become steam. The heat transfer medium of thermal oil heater is heat medium oil. The heat is transferred to the heated substance by the heat medium oil.2. When a higher heating temperature is required, such as 280 degrees, the steam pressure of the steam boiler should reach 7MPa or more, and the process piping and heat exchange equipment must also withstand the same pressure. The equipment cost is high and dangerous. Thermal oil heater provides a temperature above 280 degrees, but the pressure is lower than 1MPa.3. The temperature of thermal oil heater can be accurately controlled within 3 degrees and the temperature of the steam changes greatly.4. Thermal oil heater is used alone, the exhaust gas temperature is higher, and the thermal efficiency is lower than that of the steam boiler. However, if used in conjunction with a steam boiler, the
Question details (performance):Black smoke happens during operating. Answer: Fault reason:(1) Insufficient air volume, improper air distribution, low furnace temperature: boiler usually equipped with air preheater, but when the air preheater has leakage, hot air flow doesn't satisfy the need of burning, smoke will happen.(2) In the case of stalling situation in full automatic oil-fired boiler: significant increase of furnace negative pressure, no flame can be seen from the inspection hole, steam pressure and steam temperature drop, the steam flow decreases sharply. The water level drops suddenly and then rises sharply.(3) Incomplete fuel burning: this is the main cause of boiler smoke, in the operation, some combustible gases such as carbon monoxide, hydrogen, methane will be generated in addition to carbon dioxide, sulphur dioxide, water vapor and oxygen, nitrogen, etc. during incomplete combustion. They burn and generate black smoke. Incomplete combustion of fuel will not only lead t
(Question Details) Specific Performance:The pipe of superheater bursts in circulating fluidized bed boiler operation.The bed pressure indicator fluctuates little. Answer: causes of failure:(1) Design Factors.(2) Manufacturing process, installation and maintenance quality.(3) The temperature control device is unreasonable or does not work properly.(4) Effect of operating conditions on overheating and explosion of superheater. Troubleshooting:(1) Report the fact to operator on duty and require operating the boiler in low load.(2) When the overheat damage is serious,please report it to operator on duty and require stoping the boiler immediately to prevent blowout of the near pipes.(3) Adjust the steam temperature as much as possible within the normal range.(4) If the superheater tube is not damaged badly, it has little effect on the temperature level of the steam, and it can be allowed to run in a low load range for a short period of time.
(Details on the problem) Specific Performance:Slagging pipe blocks during operation of circulating fluidized bed boiler. Answer：cause of failure:(1) The internal shape is caused by the limited expansion of the wear-resistant material inside the slag discharge pipe. The internal components of the slag cooler are deformed, affecting the fluidization of the slag cooler; the slag cooler is deactivated for a long time or a single slag cooler is selected for slagging, and the bed material in the deactivated slag cooler is bonded under the influence of steam, which being low temperature coke.(2) The operating personnel did not grasp the ratio of the fluidized air volume of the slag cooler. Inappropriate air volume ratio resulted in poor ash slag fluidization in the slag cooler. Troubleshooting:(1) Operation personnel should strengthen understanding of boiler operating conditions, adjust boiler parameters in a timely manner, set up the concept of boiler material dynamic balance, control boiler
(Question Details) Specific Performance:(1) There are blasting sounds in the furnace, and the furnace chamber is under positive pressure. There is smoke emitted from the combustion chamber in a leakage. In severe cases, the explosion-proof door of the boiler body opens.(2) Drum water level drops rapidly and the feedwater flow rate is not abnormally larger than steam flow. MFT acts when the water level is below -280mm.(3) Drum pressure, steam flow rate, exhaust temperature decrease, smoke temperature difference increases on both sides.(4) The negative pressure at the inlet of the flue and suction fan becomes smaller and the temperature difference between the two sides increased. (5) Smoke temperature decreases at the inlet and outlet of the cyclone separator, and the temperature of the material returned is low.(6) Bed pressure increases, bed materials clean, fluidization poof, bed temperature distributes unevenly and bottom slag discharge difficultly. Answer：cause of failure:(1) Fly ash
Question details (Performance):The steam pipe vibrates violently and has a dull impact sound.Answer: fault reason: There is air in pipeline ; automatic air vent valve is not turned on; or it is out of order. Troubleshooting: Check all the air release valves on the water supply pipe and the air release valves on the top of the boiler tube for gas storage. If the valve fails, it should be replaced immediately.
Question details (Performance):1. The furnace wall at the coal economizer leaks water and steam with abnormal sound.2. The water level in the boiler drops sharply, and the water supply is obviously greater than the evaporation capacity.3. Smoke exhaust temperature and water outlet temperature rise.Answer: Fault reason:1. The water quality does not reach standard, and the oxygen in the water is decomposed into corroded pipe walls when the temperature rises.2. The low feed water temperature and smoke exhaust temperature make the inner and outer wall of the coal economizer pipe produce acid corrosion, or flying ash wear the pipe wall thin. 3. The pipe is blocked by impurities, causing overheating.4. Poor materials, defects in manufacturing, installation and maintenance. Troubleshooting:1. When economizer is slightly broke, it still maintains boiler operation, and the gap seems will not expand rapidly, in this case, load operation should be reduced, and start the spare boiler immediately,
