What are the coking methods?

Coking methods:

a) Open the ignition door, lay wood blocks of 1-1.5m range long area in front of grate (better use refractory wood blocks like tree knot, wood plate with nails prohibited), and use cotton or other combustible to ignite.

b) Flame should be in the middle of furnace, burning evenly and can not be intermittent. During boiling, fire should be gradually strengthened to avoid sudden heating. During wood coking period, open flue damper to adopt natural ventilation.

After coking more than 24 hours by wood, fuel appropriately biomass fuel for combustion and at this time shut down flue gas damper and FD fan damper, discontinuously turn on ID fan and FD fan for mechanical ventilation.

c) Temperature rise speed during coking should be according to flue gas temperature of furnace outlet, and its temperature rise speed is different according to different furnace wall structure: brick-concrete furnace wall, temperature rise can not exceed 80 °C every day and later gas temperature should not exceed 160 °C. Heat-resistant concrete wall, after normal curing period (alumina cement is about 3 days and nights, silicate and slag silicate is about 7 days and nights, then start coking. Coking temperature rise should not exceed 10 °C per hour, later the gas temperature should not exceed 160 °C, the highest temperature range duration should not be less than I day). If furnace wall is very wet, slow down temperature rise speed appropriately.

d) Coking time: light wall is generally appropriately for 3 ~ 6 days and heavy wall is generally appropriately for 10 ~ 15 days. Regularly inspect the furnace wall and control temperature properly to prevent defects such as cracks and bump.

e) Coking is qualified when up to one of the following standards: e-1) When using furnace wall ash sample method, take mortar (each about 50g) from T cross joint of refractory brick in the central of both sides of combustion chamber wall and in the central of both sides of furnace cavity outlet and its moisture content is lower than 2.5%.

e-2) When using thermometry, while temperature inside 100mm of brick wall surface in both sides of the combustion chamber is up to 50 °C, then maintain 48 hours, or joint temperature between two sides refractory bricks at furnace outlet external and thermal insulation layer is up to 100 °C, and then maintain 48 hours.

f) Pressure can not rise in boiler during coking. When pressure rises to an atmospheric pressure, exhaust steam by safety valve and fill water timely.