This news article was originally written in Spanish. It has been automatically translated for your convenience. Reasonable efforts have been made to provide an accurate translation, however, no automated translation is perfect nor is it intended to replace a human translator. The original article in Spanish can be viewed at Medida precisa de la temperatura de la llama

There are various causes which can distort the measurement of the temperature of a gas mixture

Accurate measurement of the temperature of the flame

Entheses Technology11/03/2009

March 11, 2009

Suction tubes prevent parasitic influences, to measure the exact temperature of a gas mixture: flame or smoke from burning. Measure the exact temperature of a gas mixture is not easy. The temperature indicated by a thermocouple in a gas is generally different from the actual temperature of the gas. There are various causes which can distort the measurement of the temperature: a bad exchange of heat between the gas and hot thermocouple welding; loss of heat by radiation from the hot welding and the environment that surrounds or losses by thermal conduction along the thread of the thermocouple.

The aspiration probe is designed to avoid these disturbances and to measure the actual temperature of a gas mixture. The principle is based on the aspiration to forced a part of the hot gases around the thermocouple. This aspiration increases the speed of the gas in the thermocouple hot welding and promotes the exchange of heat by convection.

On the other hand, the loss of heat by radiation from the hot welding decreases by one or more pods placed inside of the cover of the probe. The necessary gas-venting is carried out through a hole in the tip of the sheath. Aspiration catheter needs before the experimental determination of a coefficient of efficiency of the instrument and dependent on the speed of the gas-venting.

Companies that incinerated waste hazardous, and can generate dioxins, must justify to the appropriate body to their waste effectively have been pirolizado

Pyrolysis of hazardous waste

Pyrolysis of a material is heated up to a certain specific temperature which is broken down into different elements.

Companies that incinerated waste hazardous, and can generate dioxins, must justify to the appropriate body to their waste have been pirolizado effectively. It is therefore necessary to control the temperature of the gas at the foot of the fireplaces in the output of the focus with good accuracy.

Three models of probes

In practice, Pyro-control Chauvin Arnoux proposes three models of suction probes to respond to this demand for accuracy to the dimensions of the base of the chimney and the temperature of pyrolysis, which must be controlled: probe template thumbnail for use in laboratoriesis size reduced for fireplaces of extraction of less than 50 cm diameter; the probe model semi-industrial; and probe industrial model for intensive and use suitable for 1 to 2 meters in diameter chimneys.

According to the temperature you have that control, are proposed different thermocouple types: the type K up to 1100 ° C, S or R types up to 1500 ° C and the B up to 1600 ° C the detachable funnel is composed of ten pods of alumina or Platinum rodiado according to the model. It is important to know that Platinum rodiado bag can withstand temperatures up to 1900 ° c for 15 minutes. Optionally available a second exit to measure the ambient temperature.

For applications in laboratory, the miniature probes are supplied with a table of specific verifications of the lot of the thread to establish the ratio temperatura/f.e.m. own used thermocouple.

Detail of the connections of a probe of aspiration - industrial model with the option of temperature - length of about 2 m.

1) Aspiration of the gas for the measurement of the temperature of the flame

(2) Entry of the thermocouple K or S for the measurement of the temperature of the flame

(3) Option: entry of the thermocouple K or S for the measurement of the temperature environment

(4) Entry of the water for the cooling circuit

(5) Output of the circuit of water for cooling

Principle of a suction tube

The objective of a suction tube is, on the one hand, give priority to the heat transfer by convection between the gas and the thermocouple; and on the other hand, diminish losses by radiation from the hot welding.

The flame or smoke is aspire in the tube with the help of a bomb; the suction hole is located at the tip of the sheath which is easily removable. It is composed of two concentric tubes that surround the thermocouple.

The coefficient of efficiency is determined in the field. It allows to obtain the real value of the temperature of the gas removed by correction of the influence of the chosen nominal aspiration. The body of the tube, the tube in stainless, contains water cooling circuit and the aspiration of the gas circuit. The output of the measurement is performed by a cable of compensation.