DE2627077A1 - METHOD FOR THE THERMAL PROCESSING OF ASH-LICH SOLID CARBONATE FUEL - Google Patents

Description

1. Institut Chimii Akademii Nauk Estonskoj SSR, Tallin / USSR

2. Gosudarstvennyj Nautschno-Issledovatelskij Energeticheskij Institute imeni G.M. Krschischanovskogo

3. Slancechimitscheskij combine "Kiviyli" Kiviyli Estonskij SSR / USSR

4. Nautschno-Issledovatelskij Institute Slancev Kochtla-Jarve Estonskoj SSR / USSR

P 63 8o3

June 16, 19

We / Br

PROCEDURE FOR THERMAL VEEAEBBIIUIiG VCN ASCEEHBEICHEN FESTSN KAEEONATBESr.TSICFFElI

The present invention relates to a method for thermal processing of ash-rich solid carbonate fuels.

The process takes place in the production of liquid and gaseous chemical products from solid carbonate fuels, preferably from oil shale, use. The products to be obtained are raw materials for chemical synthesis.

A method for the thermal processing of oil shale is known. According to this method, the crushed slate after drying and heating in the Eei £ is flue gas atmosphere in the dryer to a temperature of 110 to 150 ⁰ C with a hot solid at a temperature of 800 to 850c in the furnace preheated heat carrier in Realst mixed or ( SU copyright certificate No. 270 684, KI. C 10b 53/06).

609885/0722

A method is also known for the thermal processing of ash-rich solid earbonaf fuel - oil shale - in a system consisting of a fuel receiving bunker, a rotating reactor and a furnace. According to this process, the dry slate, preheated in the receiving bunker with hot flue gases to a temperature of 163 to 219 C (preferably up to 19O ° C), is mixed at a rate of 36 t / h with an ash-containing solid slate in the! furnace to a temperature of 622-691 ⁰ C (677 ° up to desirable G) preheated heat carrier in a!.! close of 60 t / h to the reactor

one
feed In the reactor, the slate is mixed with the ash-containing solid heat transfer medium, heating and thermal decomposition of the slate with the formation of a gas mixture and solid residue. To ensure a temperature of the solid material intended for the process of thermal decomposition of 441 to 510 ⁰ C (desirable 483 ° C) and to accelerate the discharge of the vapor gas mixture from the reactor, the hot smoke gases, which have a temperature of 622 to 691 C, fed to the reactor in a length of 0.4 t / h. The supply of flue gas to the reactor leads to an increase in the content of roughage, carbon dioxide and nitrogen in the thermal decomposition gas.

The residence time of the steam gas mixture in the reactor is 1 to 6 minutes. Products of the thermal decomposition process are 4.0 t / h steam gas mixture and 92 t / h mixture of solid residue the thermal decomposition of slate and des

609885/0722

ash-containing solid heat carrier. Then the steam gas mixture, fed to the condensation, whereupon resin and gas are generated.

The solid residue is fed to the furnace, combustion and heating vo to a temperature from 622 to 691 ⁰ C is going on. 60 t / h of the total volume of the preheated ash-containing solid heat transfer medium is returned to the reactor, while the remaining amount is discharged from the system.

To ensure sufficient heating of the ash-containing solid heat carrier, an additional length of liquid fuel (600 to? 20 kg / h) fed to the furnace (US Patent No. 3 ^ 96094-, El. C 10b 53/06).

A disadvantage of the methods described forms a high content of harmful and fiber, ie, hydrogen sulfide and carbon dioxide in the gas and a high amount of toxic phenols at a temperature of 35O ⁰ C and a higher boiling point, in the resin of the thermal decomposition. The secondary chemical processes in the reactor exert a significant influence on the content of these components. Since all these harmful and fiber are acidic, the alkaline compounds contained in the ash-containing solid heat carrier play an important role in their collection.

According to the known method, the heating of the ash-containing solid heat carrier takes place at relatively deep ieüipe-

609885/0722

ratures that cause the formation of compounds that affect the acidic Ingredients in the composition of the ash-containing are active against solid heat transfer medium, do not guarantee.

It is the purpose of the present invention that the mentioned Eliminate disadvantages.

The invention is based on the object of developing a method for the thermal processing of ash-rich solid carbonate fuels which offers the possibility of reducing the content of harmful and Dietary fiber in the gas and phenols, which ^{boil at a temperature of 35O 0} C and higher, reduce in the resin.

This object is achieved in that a method for the thermal processing of ash-rich solid earbonet fuels is proposed, the mixing of the aforementioned solid fuel with a preheated ash-containing one. solid heat carrier, thermal decomposition until the formation of the ash-containing solid Wärmetragers comprising the solid fuel at a temperature of 475 to 50O ⁰ C with the formation of steam gas mixture and solid residue, followed by heating of the Festrückstarides, wherein according to the invention the ash-containing solid heat carrier prior to mixing with the ash-rich solid carbonate ^ fuel is heated to a temperature of 870 to 95O ^{0 C.}

609885/0722

~ 5 -

By, the heating of the heat transfer medium on the mentioned

Temperature increases the degree of decomposition contained in it

η carbonates with formation of free calcium and lagnesium oxicLe * to, which then chemically bind the acidic constituents from the target products of the thermal decomposition.

The present method of thermal processing of ash-rich solid carbonate fuels is preferred carried out as follows and explained with reference to a drawing showing the process scheme.

According to the drawing, the pre-shredded ash-rich solid carbonate fuel, for example oil shale, with a particle size of about 12 mm is continuously fed through a line to a dryer 2, to which flue gases at a temperature of 800 to 850 ^° C. are fed from below through a line 3. The oil shale is dried in the dryer 2 and preheated to a temperature of 120 to 150.degree. Together with the dry slate, the flue gases from the dryer 2 are fed through a line 5 to a dry fuel separator 6, where they are separated. After sanitary cleaning, the gas is then exhausted through line 7 to the outside. The dry slate separated in the separator 6 is transferred together with a heated ash-containing solid heat carrier separated in a separator 8 through lines 9 and 10, respectively, to the reactor

. . who fed 11. In reactor 11 there will be slate and the one mentioned solid heat carriers containing ash are mixed and deposited for a period of time that is necessary for the thermal decomposition of the

609885/0722

fers is necessary · The heating and thermal decomposition of the solid fuel takes place in the reactor 11 by physical Warne of the ash-containing solid V * ame sluggish rs at a temperature of 475-500 ⁰ C. The developed thereby vapor gas decomposition products, ie resin and water vapor as well as carbonization are diverted by a line 12 from the reactor for further processing.

After the condensation of the Daiapfgasgeiaisches, gas with an unsaturated content of about 35% by volume, including an ethylene content of 15 to 17% by volume, resin with a high content of unsaturated (20% by weight) and aromatic ( 50% by weight) of hydrocarbons and gasoline with an unsaturated hydrocarbon content of 65% by weight. The mixture of the solid residue from the thermal decomposition of shale, ie the coke and the circulating ash-containing solid heat carrier is fed through a line 13 to a furnace 14, which is fed through a line 15 with blower air from below. In the furnace 14, the organic substance of the smoldering coke is burned and the entire ash mass is heated ^{to a temperature of 870 to 95O 0 C by the heat developed in the process.}

At a preheating temperature of the ash residue of about 950 ° the degree of decomposition of carbonates is 95%, at a temperature of 870 ° it is 70 I. When the preheating temperature drops to 850 to 800 ° C, the decomposition

609885/0722

degree of carbonates corresponding to 44-25%, while the carbonates practically do not decompose ^{at a temperature below 70O 0 C.}

A temperature rise of the ash residue of over 95O ⁰ C can lead to slagging in the furnace.

The flue gases resulting from the combustion of coke are passed through together with the ash from the furnace 14 a line 16 is fed to the separator 8. In the separator 8, the heated ash-containing solid heat transfer medium is in a for the Carrying out the thermal decomposition process of the fuel in the reactor 11 required Lle ^ ge deposited. the Flue gases are fed together with the excess ash residue through a line 17 to a separator 13, where their decomposition takes place. The ash residue separated in the separator 18 is indicated by a line 19 to ;: ή ei terve use while the flue gases are fed through line 3 to dryer 2.

An advantage of the present method is that as a result of a high heating temperature (870 to 950 °) of the solid heat carrier has a high degree of decomposition of Carbonates reached in the ash-containing solid heat carrier and in this context the content of free calcium and magnesium oxides is increased therein, which gives favorable conditions of Cheinosorptions for acidic as well as fiber from the steam mixture creates.

609885/0722

The preheating of the ash-containing solid heat carrier in the furnace to the specified temperature "offers the possibility of to reduce the content of acidic compounds in the end products and the hydrogen sulfide content in carbonization gas to be reduced to zero.

When smoldering kuckersite slate in the standardized aluminum swell retort at a temperature of 51O ⁰ C, the following test data were determined, which confirm the role of free calcium oxide in the chemosorption of acidic components during thermal decomposition with the solid heat carrier.

TabeHe I

Raw material

yield

of resin

based

on orga-

niche

Substance,

Weight%

Resin density λ 20

J 20

at

Content of acidic components (phenols) ir Resin,

1. Admixture of 69.5- free Kuckersitschiefer

2. Slate + CaCO ^ (1: 2), no free Calcium oxide in front

64.3

0.966 15.0 20.0 32.1

0.940 14.0 21.5 25.5

609885/0722

3. Kuckersitschiefer + 55.0 0.902 0.0 0.7 3.0 Kuckersitschiefer ash (1: 2) (content of free calcium oxide in the mixture 13.7% by weight)

4. Kuckersitschiefer + 56.1 0.596 0.0 0.5 0, ö CaO (1: 0.2) (content of free calcium oxide in the mixture 16.7% by weight)

In connection with the higher temperature of the '.Värmeträgers the heat transfer in the reactor is better, and to supply the need for a specific IZ ₁ close of hot flue gases which contaminate the gas to thermal decomposition with fiber (C0 ~, K ~) of the reactor, falls away.

The one created in the implementation of the present method In comparison to the known methods, the following positive effect is achieved in the thermal processing of Test data determined by Kuckersitschiefer confirmed:

609885/0722

- 10 - 2627077 Resin,
2 Gev. '. ^ 2 Tabel 16.0 12.0 Stress
te on
usable
ren Prc
dukt s procedure Preheating content of the acid content
unrestrained stock of Phe-
divide temperature into nolver-
of ash, carbonisation gas, binding
ha It ig em Υοΐ. ^ ύ gen in 20th related
on or
gani
sch
Crookedness
s about star.
Ge vif t "/ o fixed ^ _G nr
Heat transfer ^H 2 ^{b ot}
ger, ⁰ C 74.4 The present 870 lanes 2.5 23 74.2 The present 950 0.0 1.5 35 74.5 Known after 850 1.0 6 _ SU copyright certificate 75.0 No. 270 684 800 1.5 10 78.0 according to US patent 690 5.0 16 font Kr. 3,496,094

For a better understanding of the present invention, specific examples are given below which illustrate the proposed method.

example 1

Ash-rich solid carbonate base fuel: cuckersite slate.

The pre-crushed slate with a particle size of about 12 mm, with a moisture content of 12.0% by weight, a

609885/0722

An organic matter content of 29.5% by weight, a calcium carbonate content of 32.1% by weight is continuously fed at a rate of 100 kg / h to the dryer, the lower part of which is fed with hot smoke gases. The dried and pre-heated to a temperature of 120 ⁰ C shale is supplied to the Eeaktor. The ash-containing solid heat carrier, heated to a temperature of 95O ⁰ C in the furnace, is likewise continuously fed to the reactor in an amount of 200 kg / h. The temperature of the products of the thermal decomposition of shale at the reactor outlet is 475 ° C.

The yield of products of thermal decomposition each 1 ton of starting slate is characterized by the following data:

Resin 150 kg

Petrol gas 13 kg

Carbonization gas 33 m ^

Heat of combustion of gas 12 000 kcal / m- ³ .

The content of free calcium oxide in aselene-containing solid The heat transfer medium is 37.4% by weight. The content of acidic components in the final products is as follows:

H ₂ S in gas 0.0% by volume
- "- 1.5% by volume
in resin 12% by weight.

609885/0722

Example 2

Made from fuel: Kuckersitschiefer with a moisture content of 10.0% by weight, an organic matter content of 2710% by weight, a calcium carbonate content of 34.8% by weight.

The procedure is carried out similarly to Example 1.

The heating temperature of the ash-containing solid heat carrier in the furnace is 87O ⁰ C.

The temperature of the products of thermal decomposition of slate at its reactor outlet is 475 ° C

Yields of products of thermal decomposition per 1 ton of starting slate are as follows:

Resin 138 kg

Petrol gas 12 kg

Carbonization gas 35 m

Heat of combustion of gas 11 500 kcal / m.

The content of free calcium oxide in the ash-containing solid heat transfer medium is 28.5% by weight.

Content of acidic components in end products is like follows:

EUS in gas traces

CO ₂ · - "- 2.5% by volume

Phenols in resin 16.0% by weight.

Example 3

Base fuel: cuckersite slate with a moisture content of 11.0% by weight, a content of organic sub-

609885/0722

punch of 38.0 wt.%, a content of calcium carbonate of 37.8% by weight.

The procedure is carried out similarly to Example 1.

The heating temperature of the ash-containing solid Y «ane carrier in the furnace is 900 ° C.

The temperature of the products of the thermal decomposition of shale at the reactor outlet is 490 ^° C.

Yields of products of thermal decomposition each Ton of starting slate are as follows:

Resin 209 kg

Petrol gas 15 kg

Carbonization gas 35.5 m ^

Heat of combustion of gas 11 650 kcal / m.

The content of free calcium oxide in the ash-containing solid heat transfer medium is 42.2% by weight.

Content of acidic components in end products is as follows:

H ₂ S in gas 0.0%

CO ₂ - "- 2.0% by volume

Phenols in resin 13.0% by weight.

Example 4

Starting fuel: oil shale with a moisture content of 13.8% by weight, an organic matter content of 17% by weight, a calcium carbonate content of 27.7% by weight, ^ p.

The procedure is carried out similarly to Example 1.

609885/0722

The heating temperature of the ash-containing solid support "is 915 ° C

The temperature of the products of the thermal decomposition of shale at the reactor outlet is 51O ⁰ C.

Yields of products of thermal decomposition per ton of starting fuel are as follows:

Resin 73 kg

Petrol gas 8 kg

Carbonization gas 25 m ^

Heat of combustion of gas 9 500 kcal / m-

The content of free calcium oxide in the ash-containing solid heat transfer medium is 21%.

Content of acidic components in end products is as follows:

HoS in gas traces

Phenols in resin 15> u wt.%.

609885/0722

Claims (1)

PATENT APPLICATION Process for the thermal processing of asehen-rich solid carbonate fuels, the mixing of the mentioned solid fuel with a preheated, asehenhaltigen solid heat carrier, thermal decomposition of the solid fuel at a temperature of 475 to 50O ⁰ C with the formation of steam gas mixture and solid residue with subsequent :? Heating the solid residue until the ash-containing solid heat carrier is formed, characterized in that the ash-containing solid heat transfer agent is heated to a temperature of 870 to 95O ⁰ C before it is mixed with the ash-rich solid carbonate fuel. 609885/0722 Blank page