Level measuring through lime kiln's ceramic wall
Level measurement in a lime kiln is difficult due to the high temperature of 1000°C inside it. Because of that isotopic measurements are often used, but the use of radioactive sources is associated with law restrictions and hindered maintenance. The solution is Gladiator microwave level switch. Its signal penetrates easily the firebrick wall.
Limestone and quicklime are often used in many industries e.g.:
- metallurgy (iron melting, steel treatment, ore flotation, alkalinity regulation, waste neutralization)
- pulp & paper (preparation of cellulose pulp)
- sugar plants (in the technological process)
- chemical industry (carbide production, paints, varnishes, other lime-based chemical compounds)
A temperature is primarily controlled variable in a lime kiln, but for proper firing, it is also necessary to control the level of lime in the hopper. Popular measuring devices either do not have the ability to penetrate the firebrick wall or, for obvious reasons, are not suitable for work at 1000°C. The sugar plant Eridania Sadam S.p.A. in San Quirico, with a production capacity of 16 thousand tons of sugar beet per day, faced the problem of effective measuring the maximum level of lime kiln filling. Previously tested microwave barriers failed because their signal could not penetrate the 200 mm thick firebrick wall.
Solution
The Hawk Gladiator Gen 3 microwave level switch was used to alarm the maximum level in the lime kiln with internal diameter of 8 m. As the only one tested, thanks to a strong signal adapting to the conditions, it was able to provide reliable alarming and finally work for all the campaign without any stops or problem related to this measurement.
Gladiator microwave switches emit a 100 Hz microwave beam. Signal strength is continuously adjusted to conditions to ensure the best performance. Mounting does not require precise positioning of the transmitter and receiver due to the wide angle of the wave distribution and their circular polarization. These features additionally provide the possibility of mounting close to the walls of the tank or chute without the risk of signal attenuation.
Features
- strong signal with high penetrability
- circular polarization insensitive to wave overlap and attenuation
- signal strength adapting to the working conditions
- versatility of application: from level signaling, through positioning of machines and devices, to preventive maintenance
- delay adjustment
- programmable, additional alarm contact
- integral and remote versions
- the possibility of remote GSM communication
Benefits
- measurement through a thick ceramic wall
- reliable level alarm
- simple assembly and service, 1-minute calibration
- information on device / application status due to an additional, programmable alarm contact
