Cross Fired Furnace, Large Capacity, Engergy Saving, Glass Furnace
1. Brief Description
Glass was used for windows and doors by the Ancient Romans as early
as the 4th century.
Glass furnace is a melting device, which is the most necessary and
important equipment for the glass industry.
The melting process is divided into five stages as following, each
section has its inner connection, affecting each other. If one
stage has imperfect performance, it will influence the next stage,
and ultimately affect the quality of glass.
glass liquid forming
At this stage, the sinter will melt, and the silicate and SiO2 in
the sinter will transform into a flint glass liquid with a lot of
gas bubbles. However, its chemical composition and properties are
not uniform.
clearing
The glass liquid is continuously heated, its viscosity decreases,
and a large amount of gaseous impurities is released, which should
eliminate the visible bubbles with the liquid pool.
homogenization
The molten glass is kept at high temperature for a long time, and
the ripples are eliminated by the diffusion function, and the whole
is homogenized. The temperature of the homogenization can be lower
than that of the clarification stage.
The defects in glass production are mainly caused by the melting
process, and the melting quality is closely related to the output
production quality, production cost, fuel combustion, kiln
activity, etc. It is important to ensure that the physical and
chemical reactions of the ingredients are well behaved throughout
the melting process and that the entire process runs smoothly to
create a high quality glass product.
2. Type of Furnace
Capacity
| Small scale furnace | Daily furnace capacity: below 50tons |
| Medium scale furnace | Daily furnace capacity: 50tons~150tons |
| Large scale furnace | Daily furnace capacity: 150tons plus |
Heating source
| Fired furnace | The combustion fuel can be natural gas, heavy oil, diesel oil…… for
this kind of furnace. |
| Electric furnace | Electricity is the fuel for this kind of furnace. |
| Fired-electric furnace | This kind of furnace is mainly using combustion fuel, electricity
is used as a supplementary heating source. |
3. Furnace structure
It is the part which melts batched materials and Clearing and
homogenizes glass liquid. In the upper space of the melting section
is referred to as the flame space, the lower part is melting tank.
The flame comes from the burner through the port, which feds in
preheated air to increase the flame effiency.
- Heat source supply section
The heated air and gas flow into the pre-combustion room for mixing
via this access after they flow out of the regenerator. This is
also an access for the flue gas to flow into the regenerator from
the flame space.
Batched materials feed into the furnace through dog house, the heat
is transferred via flame space to the glass liquid.
It is a part for cooling and homogenization of the glass liquid,
which is also an access for glass liquid distribution.
- Waste heat recovery section
A waste heat recovery device is designed for improving the flame
temperature of furnace, which could heat the combustion air and gas
by using the waste heat and then to increase the flame temperature
and save energy.
- Gas supply and waste gas exhaust
A gas supply and waste gas exhaust system is designed to ensure the
continues, regular and efficient operation of the furnace, which
includes double deck reversal unit, air and gas flue channel,
middle flue channel, blower, main flue channel and chimney.
4. Furnace melting technology system
The temperature must be strictly controlled, it will affect the
melting rate of the glass, the convection of the glass liquid, the
conditions of the glass formation, the fuel combustion, the furnace
activity and so on.
temperature
The temperature refers to the temperature of the furnace, not the
temperature of the entire furnace. The temperature profile is from
the melting tank through the length of the furnace.
pressure
The furnace pressure is the static pressure of the gas system,
which is determined by the pressure distribution curve.
bubbling
The stability of the shape and position of the bubbles is an
important indicator to measure the melting performance, which will
also affect the production capacity of the furnace and the quality
of the molten glass.
