Causes of Damage to Blast Furnace Hot Blast stove

The main reasons for the damage of the hot blast furnace include:

  • The masonry quality is not ideal, and the construction and acceptance are not carried out according to the masonry specifications;
  • The quality of the high-strength refractory fire castable in the hot blast pipe and the combustion pipe area is defective, which causes the upper brick to fall off The lining falls off;
  • The hot blast stove is changed frequently, which causes a certain degree of damage to the brick lining;
  • The operation of the furnace is not standardized, resulting in low-frequency pulsation of gas combustion, forming gas surge combustion, as the combustion capacity increases
  • Structural cracks occur when the hot blast stove cools down;
  • The arch roof combustion temperature exceeds the prescribed standard, and the arch roof fire brick lining is exposed to thermal stress and causes denudation;
  • The hot blast stove oven does not strictly follow The curve is controlled, and the oven effect is not ideal, which affects the life of the hot blast stove;
  • The daily operation and maintenance of the hot blast stove is not in place, and effective maintenance and repair measures are not taken for the hot blast stove and local redness;
  • The hot blast stove The failure of the monitoring devices and interlocking facilities of the company led to errors in post operation;
blast furnace
hot blast furnace

The quality of the tooling equipment and refractory materials required for the hot blast stove was low in the selection and selection of the hot blast stove, which affected the service life of the hot blast stove.

In order to prevent the corrosion of the furnace shell steel plate, acid-resistant paint is selected to protect the hot blast stove vault steel plate in the design. Among them, it is the key to choose a reasonable acid-resistant coating suitable for the use conditions of the hot blast stove. Monitoring method: In the past, two methods were mainly used to detect the temperature of the vault of the hot blast stove. One is to use platinum rhodium-platinum thermocouple to detect the vault temperature of the hot blast stove, which is a contact temperature measurement method, which has the advantage of high accuracy, but there are several defects:

  • The reaction speed is slow, mainly because of the poor performance of the protection tube
  • Inconvenient installation and operation of thermocouples;

(3) Short working life, there is a large amount of CO gas in the vault of hot blast stove, and CO is reducible, and it is very easy to corrode the thermocouple, which increases the maintenance cost in the later period. The other is to use a single-band infrared optical fiber to detect the temperature of the vault of the hot blast stove, which is a non-contact temperature measurement method, that is, the temperature is detected by measuring the infrared radiation emitted by the measured object through a temperature probe.