What are the effective ways of cleaning the circulating fluidized bed?

1. Active anti-fouling measures:

Design:

1. Sufficiently large furnace combustion space.The furnace adopts a full-membrane wall welded structure, and the height of the furnace is higher than that of the traditional coal furnace, and the large enough furnace space can ensure the primary burnout rate of biomass fuel in the furnace;

2. Safe combustion temperature.The furnace combustion temperature control is designed to be between 700-800 °C to prevent fuel coking.

3. Multi-point ash hoppers are designed to facilitate settlement: ash cleaning hoppers are set up in the furnace area, turning area, and convection area.

4. When the convection heating surface is designed, the pitch is enlarged, which is doubled compared with the traditional boiler pitch:

①Evaporator, arranged in series, larger transverse pitch design level longitudinal pitch, reduce dust accumulation;

② The economizer, the single pipe circles are arranged in series, and the larger lateral pitch is designed to reduce the accumulation of dust.

③The air preheaters are arranged in series, and the horizontal tubular air preheaters have a large horizontal pitch to prevent dust accumulation.

④Soot blowers are installed on the heating surfaces of the convection pipe, economizer and air preheater respectively.

Installation: Strictly control the pitch of the tube bundles to avoid the pitch reduction caused by installation errors, resulting in serious dust accumulation.

2. Passive anti-fouling measures:

Operation: soot blowers are regularly used, and soot is cleaned manually on a regular basis.

3. Selection of soot blowing form:

Commonly used soot blowers for boilers include sonic soot blowers, compressed air soot blowers (with limited pressure), shock wave soot blowers, and steam soot blowers (the pressure and temperature of the steam source are required, otherwise the soot blowing effect will be affected), etc. From the analysis of soot blowing effect and input cost, steam soot blowing effect is the best, shock wave soot blowing effect is second, and compressed air and sound wave effect are the worst.