JPH0212997B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for producing lignite obtained by briquetting in the presence of a binder and with the use of other additives, which binder may already be present originally, as is the case with many lignite coals, or may be briquettes based on fuels such as coal, coke, lignite, charcoal, etc., which are additionally formulated in addition to additives.

It is known to produce briquettes by pressing from powdered, finely divided or coarse-grained materials. There is a difference between a process without a binder during the briquetting process and a briquetting process with the addition of an organic or inorganic binder.

By adding a binder, the briquetting state of the pressed product is improved during briquetting, e.g. it becomes better plasticized during the forming process, and at the same time the binder also increases the cohesive strength of the briquetteted material and thus makes handling of the briquettes easier. It can be improved. In particular, the added binder has an advantageous influence on the properties of the briquettes, such as hardness, flame resistance, combustion efficiency, smoke generation, etc.

A large number of binders used in briquette processing are already known, such as coke, anthracite, lean lime and glutinous charcoal. However, the conventionally known briquettes and their manufacturing methods have various drawbacks. For example, pitch or asphalt bitumen is used as a binder for briquettes, which emits considerable smoke on combustion and rapidly disintegrates due to softening of the binder. This in particular means that the material present is not fully utilized during combustion, and a significant amount of unburned carbon still remains in the ash. As a result, up to approximately 60% of carbon is still present in the ash, which is either discarded without being utilized as waste or has to be recovered in a laborious manner.

Coal tar pitch as a binder has the disadvantage that carcinogens may be present and its use should therefore be avoided as much as possible; the use of pitch as a binder in briquettes used as household fuel is prohibited. , prohibited for environmental protection reasons.

Furthermore, there is a series of lignite coals that can be easily briquette-processed without the addition of additional binders. This is because these brown coals inherently contain about 5-10% organic components that act as binders. However, the mechanical properties of briquettes of this type are not sufficient for special applications. Difficulties arise particularly when lignite briquettes of this type are used for coking purposes.

German Patent Application No. 11 86 825 describes the use as a binder of the sulfite waste liquor produced when obtaining the pulp, which has to be treated with charcoal in a special manner. In addition to the specific binder, 0.1 to 1% of oil can also be added to the briquetting compound as a further additive.

Although a series of briquettes containing a binder in addition to the fuel and their production are already known, improved methods of producing briquettes from fuels such as charcoal, coke, charcoal, lignite, etc. and briquettes with improved properties are also available. The demand for seed briquettes continues to exist.

Therefore, the problem of the present invention is to prevent damage that cannot be ignored.
It is concerned with providing a smokeless briquette made of fuel produced in the presence of a binder, which does not produce fine dust or dust and can be handled well, and which also has high cold-resistance properties and especially high flame resistance. A further object of the invention is to provide a ash which is characterized by high efficiency during combustion and which contains very little or no unburnt components, and which is also well coked and has a wide range of uses. The object of the present invention is to obtain a fuel briquette that yields coke with excellent mechanical properties that can be used. A further object of the present invention is that it can be used in the processing of practically all solid fuels, especially bituminous coal, mochi charcoal, poor lime, blacksmith coal, anthracite, coke, lignite, charcoal, etc.
The object of the present invention is to provide an advantageous method of producing improved briquettes containing binders by a simple briquetting technique which allows the use of a variety of binders and which can be carried out on conventional briquetting equipment.

This task involves combining monomeric aliphatic dihydroxy compounds with an aliphatic group of at least 10 carbon atoms on one of the carbon atoms between the two hydroxy groups, polyisocyanates and aliphatic monomers containing tertiary nitrogen. About 0.1 to 10% by weight of cationic polyurethanes obtained by reacting with diols to quaternize the tertiary nitrogen or by reacting polyisocyanates and corresponding aliphatic monomer diols in which the nitrogen has already been quaternized. , about 0.1 to 19% by weight of a natural or synthetic binder and about 80 to 99% by weight of a fuel that is actually solid. Ru. The fuel briquettes may contain 80-99% by weight charcoal and 80-99% brown coal. In this case it is also possible to use lignite which originally contains 5 to 10% of natural components which act as binders.

Advantageously, the fuel briquettes contain a bitumen-based binder. Also very advantageous are fuel briquettes according to the invention containing 80 to 99% coke or lignite coke.

To prepare this briquette, a monomeric aliphatic dihydroxy compound having an aliphatic group of at least 10 carbon atoms on one of the carbon atoms between the two hydroxy groups is mixed with a polyisocyanate and a tertiary nitrogen-containing compound. Cationic polyurethanes obtained by reacting with monomeric aliphatic diols to quaternize the tertiary nitrogen or by reacting with polyisocyanates and corresponding aliphatic monomeric diols whose nitrogen has already been quaternized. Approximately 0.1~
10% by weight, about 0.1-19% by weight of natural or synthetic binders
and about 80 to 99% by weight of pulverized fuel can be mixed together and formed into briquettes in a manner known per se.

It is particularly advantageous if the pulverized fuel, binder and cationic polyurethane are mixed cold. The briquettes thus obtained are particularly suitable for coking.

The cationic polyurethanes used as additives according to the invention are monomeric aliphatic dihydroxy compounds whose hydroxy groups are bonded to each other by preferably up to 7 atoms in the aliphatic chain. produced by reacting with an isocyanate and an aliphatic monomer diol (which contains a tertiary nitrogen) and quaternizing the tertiary nitrogen by treating it wholly or partially with an acid or a quaternizing agent. be able to. Instead of using monomeric diols with tertiary nitrogen atoms and subsequent quaternization, it is also possible to use corresponding monomeric diols in which the nitrogen has already been fully or partially quaternized. When producing these cationic polyurethanes, intermediate products with NCO end groups are first produced by reacting dihydroxy compounds with polyisocyanates, which are then chain-extended. This also allows the starting components to be reacted in a so-called one-shot process.

Monomeric aliphatic dihydroxy compounds include in particular glycerol aliphatic monoesters such as glycerol monostearate or aliphatic compounds such as N
-stearyldiethanolamine, 1.2- or 1.4
-Dihydroxyoctadecane is suitable.

The cationic polyurethanes that can be used in accordance with the invention and the corresponding production methods are described in detail in German Patent Application No. 24 00 490.

Cationic polyurethanes can be used as anhydrous materials in aqueous solutions or dispersions of various concentrations. For example, cationic polyurethane 15-30
Preference is given to aqueous solutions or dispersions containing % by weight.

pulverized actually solid fuel, i.e. granules;
The mixing of the fuel in the form of fines, dust or the like with binders and additives can be carried out in a conventional manner. Furthermore, additives can be sprayed or splashed onto the briquette product, ie onto the existing mixture of fuel and binder. All three components can also be combined together. It is particularly advantageous if the mixing is carried out in the cold. Mixing can be carried out in conventional stirring devices, mixers and mixers.

According to the invention, different fuel materials can be used. All kinds of charcoal can be briquette-processed, such as bituminous coal, mochi charcoal, poor coal, blacksmith coal, anthracite coal, etc. Particularly suitable are brown coals of various origins. Charcoal is also highly suitable within the framework of the invention.

It is particularly surprising that very low smoke briquettes are obtained according to the invention. The production of briquettes can be carried out using simple briquetting techniques and does not require the use of special processing techniques. Briquette compounds can be formed on conventional machines. Suitable briquetting machines are, for example, roller presses, ring roller presses, extrusion presses, etc.

The hardness of the obtained briquettes is very good, and therefore the briquettes are easy to handle.
It is characterized by almost no disintegration and hardly any fine dust or dust. Pressure resistance is remarkable. What is particularly surprising is the excellent flame resistance of the briquettes according to the invention.

A particularly advantageous embodiment of the invention uses polyvinyl alcohol as the synthetic binder in the briquetting process. In this case, a particularly good weight ratio of cationic polyurethane to polyvinyl alcohol is from 1:3 to
The ratio is 3:1. The viscosity of the polyvinyl alcohol is advantageously between 0.003 and 0.07 Pa.s, in which case the viscosity is 4
% aqueous solution at 20°C. Commercially available polyvinyl alcohol, which is generally produced by saponifying polyvinyl acetate, is suitable for producing fuel briquettes of this type. Polyvinyl alcohols with different degrees of polymerization and viscosities can also be used. The viscosity given within the framework of the invention is 4 at 20 °C.
% aqueous solution. Particularly suitable is fully saponified polyvinyl alcohol.

Suitable commercially available polyvinylallols within the framework of the present invention are available, for example, from Hoechst under the trade name MOWIOL.
Company newsletter “BI Das Mowiol-Sortiment” and “AI
Zur Geschichte des Mowiol” (Hoechst AG,
G1103, September 1976) describes this type of polyvinyl alcohol in detail.

Processing of the solid fuel, cationic polyurethane and synthetic binder polyvinyl alcohol can be carried out in the manner described above. Although the present invention relates to the production of fuel briquettes from conventional solid fuels, charcoal-based briquettes, especially anthracite-based briquettes, are sometimes advantageous. Briquettes of this type have high cold resistance.

This feature of the invention is achieved through the use of cationic polyurethane and polyvinyl alcohol as synthetic binders. There is no need to use other binders. However, it is also possible to use other binders, for example natural or synthetic binders, in conjunction with the abovementioned additional components.

In particular, it could not have been predicted that this example would result in a fuel briquette with very low smoke and excellent mechanical properties with high utilization. In particular, the cold resistance of the briquette is improved, resulting in a fuel briquette that can be handled well both at room temperature and at high temperature. The present invention can be practiced with very small amounts of binders and additives, and can be achieved by incorporating only about 1% by weight total of additives and binders into the solid fuel. Of course, the effects can be produced even in smaller amounts.

It is not necessary to use large amounts of binder and in many cases can be processed with less than previously used. In other words, it is possible to reduce the amount of bitumen added when briquetting charcoal by several percent.

A further advantage is that the moisture content of the charcoal does not have to be significantly reduced before briquetting. The briquette is
It is possible to process charcoal with a moisture content of 1.5% or more, and in many cases with a significant moisture content, i.e. up to 20%.

Charcoal containing very large amounts of water, e.g.
In the case of brown coal that has been pre-dried only slightly to 20%, it is possible according to the invention to maintain its moisture content very high by adding additives, so that the binder present is distributed homogeneously into the coal component. Distributable.
It is not necessary to add agents such as caustic soda and acids, which are often used to increase wettability.

It was particularly unexpected that all types of charcoal could be processed by the present invention. Each type of charcoal can be processed individually. Therefore, in the case of charcoal that is difficult to briquette, it is not necessary to mix several types of charcoal, as was often done in the past, by adding other charcoal, such as rice cake charcoal, to obtain briquettes.

No foul odor occurs when burned. The binder and additives are very well distributed in the charcoal and no undesirable agglomeration occurs. Only a very short mixing process is required. The use of additives is harmless.

Fine particles as well as coarse particles can also be used separately or mixed together. It is also possible to use powdered charcoal. The weather resistance of the briquettes is also perfect.

Briquettes produce only a small amount of waste when burned and in most areas of use. It is particularly surprising that this briquette has an inherently high degree of utilization and effectiveness. The combustible components in the embers are significantly reduced.

The briquettes according to the invention are particularly suitable for use in coking, where they exhibit good mechanical properties, particularly advantageous properties at high temperatures. The coke produced in the coking of briquettes according to the invention has increased hardness properties and can be used in many fields.

The invention will now be explained in more detail by means of examples: Example 1 Preparation of cationic polyurethane used as additive Equipment: heating capacity of 500 ml, equipped with stirrer, reflux condenser with drying tube and addition funnel. Use a three-necked flask. 19.5 g (0.0545 mol) of commercial quality glycerin monostearate is pre-placed into the flask. 15 mg of dibutyltin diacetate, 24 ml of anhydrous acetone and 16.0 ml (19.5 g) (0.112 mol) of a mixture (80:20) consisting of toluylene diisocyanate (2.4) and (2.6) are added in sequence.

The reaction vessel is then heated under stirring for 30 minutes until the solvent is slightly refluxed. During this time, the reaction temperature is approximately 65℃
It is.

A solution of 6.5 g (0.0546 mol) of N-methyldiethanolamine in 20 ml of anhydrous acetone is then added dropwise over the course of 10 minutes, followed by heating again so that a gentle reflux is maintained. NCO less than 1.5% after 60 minutes reaction time
The contents precipitate, giving rise to a mildly viscous, aqueous, clear solution of polyurethane, which is diluted by adding 160 ml of technical grade acetone.

Add 27.3ml of 2N hydrochloric acid within about 5 minutes to make salt. The salt is then partially colloidal and partially present as a white precipitate, which is dissolved by adding 140 ml of water over a period of 15 minutes, maintaining the temperature of the flask contents at about 50°C. The acetone is removed from the resulting clear solution by vacuum distillation.

A slightly cloudy, slightly yellowed polyurethane ionomer solution of 20% by weight resulted.

The concentration can be increased by further distilling off water. At 32% by weight the polymer solution is still slightly fluid.

Example 2 Briquetting of coal In a mixer, 93 parts of a fine-grained mixture of anthracite and wrought coal (particle size <3 mm), 5 parts of bitumen and the polyurethane according to Example 1, calculated as dry matter and used as a 20% by weight aqueous solution Combine 2 parts at room temperature. The mixture is then heated in a subsequent simmering machine for approx.
Warm to 130℃. The briquetting mixture thus prefinished is pressed in a roller press in the usual manner. The still warm briquettes are then stored for a further approximately 30 minutes for cooling and hardening. The briquettes thus produced have a hardness approximately 30% higher than briquettes produced without the addition of the cationic polyurethane according to the invention.

Example 3 Briquetting processing of brown coal Brown coal is dried to a moisture content of 17% and crushed to a particle size of 6 mm or less. Cationic polyurethane 3% according to example 1
After adding (calculated as dry matter), mixing and warming, the mixture is formed into briquettes in a conventional extrusion press. After pressing, the briquettes are stored for a further approximately 6 hours for cooling. The hardness of the lignite briquettes is improved by up to 50% compared to the hardness of briquettes obtained without the addition of the cationic polyurethane according to the invention.

Example 4: Briquetting charcoal Charcoal is crushed into particles with a particle size of 10 mm or less using a crusher, as is commonly used for lime. Then charcoal 80
18 parts of bitumen and 2 parts of the cationic polyurethane according to Example 1 (calculated as dry matter) are mixed and formed into briquettes in a roller press at a temperature of 130 DEG C. After pressing, the briquettes are stored for a further approximately 0.5 hour for cooling. The briquettes have improved hardness.

Example 5 Briquetting of coke powder 88 parts of coke powder, 10 parts of bitumen and 2 parts of the cationic polyurethane according to Example 1 (calculated as dry matter) are mixed together and pressed into briquettes in a roller press at a temperature of 130°C. do. After cooling and storage, the briquettes have improved hardness compared to coke briquettes produced without the addition of the cationic polyurethane according to the invention.

Example 6 Anthracite briquette processing course 100Kg in the mixer,
1 kg of cationic polyurethane according to Example 1 and fully saponified polyvinyl alcohol [viscosity approx. 4 _cP ]
(=0.004Pa.s) MOWIOL4-98 (MOWIOL4
-98) Made by Hoechst] Fill 2 kg in sequence.

Mix each component intimately for 5 minutes and introduce into a double roller press. The mixture is heated briefly with steam before being processed into briquettes.

The briquettes obtained emit particularly little smoke during combustion and have a hardness value of approximately 80 dN/cm ² after 20 minutes.
The carbon content in the roasted smoke is minimal.

Example 7 In a stirrer, 0.5 kg of the cationic polyurethane used in Example 6 and 0.5 kg of the polyvinyl alcohol used in Example 6 are combined. Stir both components until a uniform mixture is obtained.

Anthracite 100, which is made from a mixture of normal grain components
Add to Kg in several batches. 〓After intimate mixing in a machine, the coke is heated in a double roller press for 110
℃ steam treatment and briquette processing.

After a short curing time, hard briquettes are obtained which are distinguished by a particularly slight roasting.

Claims (1)

[Claims] 1 (1) 1 of the carbon atoms between the two hydroxy groups
reacting a monomeric aliphatic dihydroxy compound containing an aliphatic group having at least 10 carbon atoms with (2) (a)(i) a polyisocyanate and (ii) an aliphatic monomer diol containing a tertiary nitrogen; The tertiary nitrogen is then quaternized or cationic, obtained by reacting (b) with (i) the polyisocyanate and (ii) the corresponding aliphatic monomer diol in which the nitrogen has already been quaternized. polyurethane
A fuel briquette containing a binder and an additive obtained by briquetting about 0.1-10% by weight of a natural or synthetic binder, about 0.1-19% by weight of a solid fuel, and about 80-99% by weight of a solid fuel. 2. The fuel briquette according to claim 1, containing 80 to 99% by weight of charcoal. 3. The fuel briquette according to claim 1, containing 80 to 99% by weight of lignite. 4. A fuel briquette according to claim 1, wherein the lignite contains 5 to 10% of natural components as binders. 5. A fuel briquette according to any one of claims 1 to 3, containing a bitumen-based binder. 6. A fuel briquette according to claim 1, containing polyvinyl alcohol as synthetic binder. 7. The fuel briquette of claim 6, wherein the weight ratio of cationic polyurethane to polyvinyl alcohol is from 1:3 to 3:1. 8 Claim 6 or 7 containing polyvinyl alcohol with a viscosity of 0.003 Pa.s to 0.07 Pa.s
Fuel briquettes as described in section. 9. A fuel briquette according to any one of claims 6 to 8, containing fully saponified polyvinyl alcohol. 10. A method for producing fuel briquettes containing binders and additives, comprising: (2) reacting the dihydroxy compound with (a)(i) a polyisocyanate and (ii) an aliphatic monomer diol containing a tertiary nitrogen, and then quaternizing the tertiary nitrogen; or (b)(i) Cationic polyurethanes obtained by reaction with polyisocyanates and (ii) corresponding aliphatic monomer diols whose nitrogen has already been quaternized.
about 0.1 to 10% by weight of a natural or synthetic binder, about 0.1 to 19% by weight of a pulverized fuel, and about 80 to 99% by weight of ground fuel, which are mixed together and formed into briquettes in a manner known per se. Method of manufacturing fuel briquettes containing additives. 11. Claim 1, in which the pulverized fuel, binder and cationic polyurethane are mixed together when cold.
The method described in item 0. 12. Process according to claim 10, in which polyvinyl alcohol is also used as synthetic binder. 13 (1) Monomeric aliphatic dihydroxy compounds containing an aliphatic group having at least 10 carbon atoms on one of the carbon atoms between two hydroxy groups, (2) (a)(i) polyisocyanates and (ii) react with an aliphatic monomer diol containing a tertiary nitrogen and then quaternize the tertiary nitrogen, or (b) react with (i) a polyisocyanate and (ii) a corresponding aliphatic monomer diol in which the nitrogen has already been quaternized. Cationic polyurethane obtained by reacting with aliphatic monomer diol
Using a fuel briquette containing binders and additives obtained by briquetting approximately 0.1-10% by weight natural or synthetic binder approximately 0.1-19% by weight crushed fuel approximately 80-99% by weight A coking method characterized by: