Boiler smoke and wind mixed heating adjusting system and control method thereof

Abstract

The invention relates to a boiler smoke and wind mixed heating adjusting system and a control method thereof. A heat exchanger located in a flue is arranged on the inlet side or the outlet side of a dust remover, a fan is installed at an air inlet of the heat exchanger, an air outlet of the heat exchanger communicates with a hot air intake port at a flue on the outlet side of a desulfurizing towerthrough a first pipe, and a first ventilation door is arranged on the first pipe; and the air outlet of the heat exchanger communicates with an air inlet of an air feeder through a second pipe, and asecond ventilation door is arranged on the second pipe. According to the boiler smoke and wind mixed heating adjusting system and the control method thereof, the smoke temperature of the dust removeror an inlet of the desulfurizing tower is reduced, protection of the dust remover is promoted, the loss of desulfurization water and discharge of waste water are reduced, hot air is fed into a primary fan, and the drying capacity of a coal mill can be greatly improved; the hot air is mixed and enters a chimney, and white smoke plume visual pollution can be effectively eliminated; temperature measuring points and a controller are installed, so that closed-loop control of the temperature is achieved, an expected effect can be effectively achieved, and the economic efficiency and environmental protection property of the device are adjusted to an optimal balancing state.

Description

technical field [0001] The invention relates to the technical field of flue gas treatment of coal-fired boilers, in particular to a boiler flue-air mixing temperature raising regulation system and a control method thereof. Background technique [0002] The pulverized coal used in the pulverized coal furnace is made by grinding lumpy raw coal with a coal mill. In order to improve the combustion effect and grinding efficiency, it is necessary to heat the cold air through the air preheater installed inside the boiler and then turn it into hot air. The hot air is blown into the coal mill to increase the drying and grinding output to assist the research. The hot air carries the coal powder into the furnace for combustion. The high-temperature hot air has the effect of supporting combustion. It is necessary to control the outlet temperature of the coal mill within a certain temperature range to achieve safety and The balance of economy, in actual production, because the raw coal c...

AI Technical Summary

Problems solved by technology

The flue gas temperature at the outlet of the air preheater is usually 120°C-150°C. The flue gas enters the desulfurization tower after passing through the dust collector. The temperature of the flue gas discharged from the desulfurization tower is usually 45°C-50°C, which will evaporate and carry away a large amount of desulfurization The tower sprays water, resulting in waste of water resources and excessive discharge of desulfurization wastewater

At the same time, the high-humidity flue gas discharged from the desulfurization tower is sent into the chimney and discharged into the atmosphere. Because of the high humidity of the flue gas, a "gypsum plume" phenomenon of white smoke is often produced at the chimney outlet, causing "negative" visual pollution and causing "negative" visual pollution in the chimney. A large number of aerosol "fog droplets" will be formed at the exit and fall to the nearby area, causing further sensory pollution to people and increasing the formation of smog.

One of the existing methods to solve the white smoke from the chimney is to install a hot water circulation heat exchanger at the chimney inlet. Since the low-temperature and high-humidity furnace smoke contains sulfur oxides, it is easy to form acid dew at low temperatures and is extremely corrosive. Fluoroplastics are used as the heat exchange surface, and the use of fluoroplastics as the heat exchange surface has low heat exchange efficiency, large investment, large space occupation, and large new resistance of the flue

The bag filter is an ultra-low emission dust removal equipment. If the flue gas temperature is too high or too low, it will affect the dust removal effect and safety of the bag. It is necessary to maintain the temperature of the flue gas within a certain range to ensure the safety and safety of the bag filter. Dust removal effect, in production practice, there is a problem that the outlet temperature of the air preheater is too high and difficult to adjust and control

Changes in boiler load, external conditions, and internal and external moisture of coal-fired coal have been fluctuating in a large range, and the temperature of the flue gas entering the outlet of the air preheater will change drastically, which brings troubles to temperature regulation and control. This requires the study of a set of boiler flue gas temperature regulation and control method and the regulation and control system using this method to realize the synchronous regulation of the flue gas temperature at the inlet of the bag filter and the inlet of the chimney, and to dynamically adjust the temperature of the flue gas under different working conditions. temperature, to control the wind and smoke temperature in different locations within their respective target ranges

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