JPS5821522B2 - Fractional distillation method for thermal decomposition products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for fractionating a thermal decomposition product, and in particular, when a polymer substance is thermally decomposed to obtain a decomposition product, water in the decomposition product is separated during the condensation process of the thermal decomposition. Regarding how to.

Pyrolysis has been carried out by various methods for the purpose of liquefying various solid organic substances, but the method for recovering liquid products from pyrolysis and combustion is simply air cooling of the decomposed and vaporized substances. It is often collected by cooling and condensing using a heat exchanger such as water or water cooling.

When attempting to recover the thermal decomposition liquid of a sample containing a large amount of moisture, such as a cellulosic material such as a plant, wood, paper, or cotton, using this conventional recovery method, due to the influence of the large amount of moisture in the decomposed and generated gas, The gas temperature drops rapidly and easily becomes below the boiling point of water, making it impossible to separate water from substances with a temperature above the boiling point of water.

The cellulose oil thus obtained inevitably contains a large amount of water, and this water content of 30 to 50% poses a major obstacle to its utilization.

Furthermore, it is extremely difficult to separate water from the cellulose oil thus obtained.

For example, when attempting to dehydrate cellulose oil by distillation, the initial boiling point is approximately 60°C, but the boiling point of the drained water reaches 100°C, and during this distillation, it dissolves in the bottom liquid of the pot. Tar precipitates and becomes a black paste, and as the temperature rises, solidification and secondary decomposition occur.

In this way, the pyrolysis liquid after water is separated by distillation turns into a substance completely different from cellulose oil.

The present invention solves the above-mentioned drawbacks of the prior art. That is, the present invention solves the problem of the above-mentioned drawbacks of the prior art. That is, when pyrolyzing organic materials containing a lot of moisture such as plants, wood, paper, cotton, cloth, plastics, kitchen waste, etc., the product is A heater, heat insulating material, and cooler are installed in the distillation route to create a temperature gradient to raise the temperature on the processing equipment side, and several outlets for the condensate are installed in areas with this temperature gradient. , maintaining the temperature of at least the first condensate outlet at a temperature equal to or higher than the boiling point of water;
This is a method for separating water from liquid products in a combustion and thermal decomposition treatment device and crudely separating fractions by condensation temperature, which is characterized by extracting tar, oil, water, etc. according to condensation temperature.

That is, in the present invention, the temperature at least at the initial condensate outlet must be maintained at a flow rate higher than the boiling point of water.

For example, condensation of water is avoided by maintaining a temperature of about 110 to 200°C, and oil with a high boiling point is condensed at the first outlet, and water is collected separately from the rear outlet.

FIG. 1 is a schematic diagram of a fractionating apparatus for carrying out the method of the present invention, in which a sample 8 placed in a reactor 7 is thermally decomposed by a fluid heat medium 9, and the generated thermal decomposition products are are heating heaters 10, 11, 12, 1 with different temperatures, respectively.
3. Cooled to the condensation temperature of each substance by coolers 14 and 15, and collected in liquid form into respective receivers 123456.

A heat insulating material 1617 is wrapped above the reactor 7 and around the heaters 10 to 13.

There is also a thermometer T at each important point. - T6 is provided, cooler 1
Hot water 18 is passed through the cooler 15, and cold water 18 is passed through the cooler 15.

The product that is not liquefied to the end becomes exhaust gas 20 and is released.

According to the method of the present invention, which separates water during the condensation process of pyrolyzed liquid, it is possible to produce low-calorie liquid fuel from plants, whereas previously cellulose pyrolyzed liquid was difficult to dehydrate and was treated as a nuisance. It is also possible to do so.

For example, the calorific value of cellulose oil recovered by carbonizing wood at 450°C using the conventional method is approximately 2000 cal.
/P, and cannot be used as a fuel alone as it is, and cannot be used unless mixed with other high-calorie fuels, but according to the method of the present invention, approximately 4,000 to 600
Cellulose oil of 0 cal/P is easily separated from water during the condensation process of the pyrolysis liquid, and cellulose oil that can be combusted as it is is obtained.

Furthermore, when the pyrolysis liquid roughly separated by condensation temperature is used as a chemical raw material, it contains no or very little water, resulting in a high concentration (very advantageous compared to pyrolysis liquid obtained by conventional methods). .

The present invention will be specifically described below with reference to Examples.

Example 1 Using the apparatus shown in FIG. 1, wood chips 6 were placed in a reaction vessel 7.
0'? The temperature at the upper position of the condensate receivers 1, 2, 3°4 is 1 meter, T3, T4, T5, and Ta are each 1.
The temperature was controlled by heating with a heater so that the temperature was 60°C, 120°C, 100°C, and 80°C.

Further, 55° C. hot water 18 was flowed into the cooler 14, and 5° C. cooling water 19 was flowed into the cooler 15.

After the temperature at each condensing position reaches the set temperature and stabilizes, 450
The reaction vessel 7 was immersed in a fluidized heating medium 9 at 0.degree. C. to carry out thermal decomposition.

The generated pyrolysis gas and steam passed through a temperature-controlled line, and a condensation phenomenon was observed in the condensate receivers 1 to 6, and the generated liquid was accumulated in each receiver.

Visually, the properties of the condensate are as follows: 1 has a black tar-like substance in the receiver, 2 has a pale yellow transparent liquid with a small amount of tar-like substance mixed in, 3 has a pale yellow transparent liquid, and there is not much difference between 4 and 3, but there is a slight difference. There was a mixture of cloudy white liquids. No. 5 had the largest amount of liquid and was pale yellow in color, giving the impression that the liquid was slightly cloudy. No. 6 had the least amount but was transparent and pale yellow in color, paler than the others.

The measurement result of the calorific value of each condensate using a pump calorimeter is 1
5300 cal/P for 2, 4200 cal/P for 2
l/! P, 3 is 3600 cal/P, 4 is 2100 c
al/P, 5 was 0.6 was 2500 cal/fl.

FIG. 2 is a graph showing the relationship between the distillation rate and calorific value of each condensate.

The measurement results of the calorific value revealed that most of the water contained in the wood pyrolysis liquid was concentrated in the 50 receiver, and that the present invention could roughly separate water in the coagulation process of pyrolysis.

The other condensate from which water was roughly separated had a higher calorific value than the cellulosic pyrolyzed liquid produced by the conventional method, and a cellulosic pyrolyzed liquid that could be combusted as it was was obtained.

In addition, the thermal decomposition liquid of cellulosic substances obtained by conventional methods has been treated as a nuisance, but the condensation temperature fraction obtained by the method of the present invention cannot be obtained by distillation of cellulosic thermal decomposition liquid by the conventional method. It is thought that it cannot be used as a raw material for chemicals.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a fractionating apparatus for carrying out the present invention;
FIG. 2 is a graph showing the relationship between the distillation rate and calorific value of each condensate. 1-6... Condensate receiver, 7... Reactor, 8... Sample, 9... Fluid heat medium, 1
0-13...Heating heater, 14,15...
... Cooler, 16.17 ... Heat insulation material.

Claims (1)

[Claims] 1. After thermally decomposing an organic substance containing a large amount of water, when cooling the thermal decomposition product and recovering it in liquid form, the temperature gradient can be reduced by installing a heating heater, a heat insulating material, and a cooler in the distillation path of the thermal decomposition product. and provide condensate outlets at multiple locations along the route, and maintain the temperature of at least the first condensate outlet at a temperature equal to or higher than the boiling point of water to separately recover water and other fractions. Characteristic method for fractionating pyrolysis products.