DE1671365B1 - Process to increase the fire resistance and to improve the surface of hard coal and lignite briquettes - Google Patents

Description

The invention relates to increasing the fire resistance of Hard coal and lignite briquettes and the improvement of their surface.

The fire resistance of: solid fuel stoves - preferably of briquettes-can by determining the proportion of unburned matter in the rust diarrhea measured during heating, burning and stoking.

Especially with today's modern heating systems with lower Abbrwid, the heating material (briquettes) is more stressed than before. This applies above all to heating systems with a larger filling shaft height. The heating material (briquettes) - mg SEN therefore have particularly high refractoriness.

In the. Verbrehrinni: the briquettes produced according to the previously known methods - more or less unburned food gets into the roasted diarrhea. This will make the Utilization of the calorific value of the respective fuel. decreased.

It is also already: tekannt, bestimrrft2- "Ü erinstoffen to lower the ignition temperature and the melting point of the ash or slag, inter alia, trisodium phosphate add or as catalysts fixed on combustion fuels compounds to be used which, as cations, boron, chromium, manganese Contains iron, sodium, potassium, magnesium, aluminum, calcium, barium and strontium and, as anions, sulfates, persulfates, carbonates, percarbonates, chromates, bichromates, borates, perborates, manganates, permanganates and oxygen derivatives of phosphorus.

In practice, however, lengthy studies have shown that that with these known additives the desired success cannot be achieved and In particular, the fire resistance of hard coal and lignite briquettes does not can improve. Contrary to expectations, the use of the most varied resulted Phosphates to failures that suggested abandoning these attempts.

Surprisingly, however, it was finally found that a significant Improvement of fire resistance by adding sodium tripolyphosphate can be achieved that the raw materials alone or in addition to other already known binders and / or additives added during briquette production or through post-treatment is applied to the finished briquettes. The sodium tripolyphosphate can after of the present invention also in combination with clay, with clay and quartz flour Clay and "water glass, with pitch, sulphite waste liquor, etc., are used. Otherwise is done the production of the briquettes in the usual way.

The sodium tripolyphosphate is preferably used in amounts below 2% added.

At the same time as the fire resistance due to the additives mentioned, there is an improvement in the surface of the briquettes, which can be reinforced by post-treatment with hydrophobicizing agents or by adding binders or to the briquetting charcoal. The following examples illustrate the Advantages of the invention, with the respective example 1 serving as a comparative example. - Example group A - - similar hard coal briquettes, produced with coal tar pitch as a binder Example 1 hard coal briquettes (anhydrous ash content 7.5%), produced from a mixture of 92 parts of briquetting coal , 7 parts coal tar pitch and 1 part emulsion (20 % calcium sulfite waste liquor with 50% solids content, 20 % coal tar heating oil and 60% water).

The oven test in a long-life oven with lower burn resulted in: Burning time 120 hours Composition of the ash: 45% flammable 55% non-flammable reduction the heating power (based on the combustible components): 6.6% Example 2 hard coal briquettes (Ash content anhydrous 7.5%), made from a mixture of 91.5 parts Briquetting coal, 7 parts coal tar pitch, 1 part emulsion (as in the example 1), 0.5 part of sodium tripolyphosphate.

Oven test as in Example 1. Composition of the ash: 15 % flammable, 85% non-flammable. Reduction in heating output (based on the combustible components): 1.8%. Example group B Hard coal briquettes, produced with sulphite waste liquor as a binder Example 1 Hard coal briquettes (anhydrous ash content 60%), produced from a mixture of 87 parts of briquetting coal and 13 parts of ammonium beech sulphite waste liquor (solids content 50%), were raised to 250 for 45 minutes ° C heated.

The oven test with a long-life oven with lower burn resulted in: Burning time 120 hours Composition of the ash: 75% combustible 25% non-combustible Reduction of the heating output (based on the combustible components): 19.2%. Example 2 Hard coal briquettes (ash content anhydrous 60%), produced from a mixture of 85.7 parts of briquetting coal, 13 parts of ammonium beech sulphite waste liquor (solids content 50%), 0.5 part of sodium tripolyphosphate and 0.8 part of clay with 30% ° / a A1203, finely ground, heated as indicated in Example 1. Oven test as in example 1.

Composition of the ash: 28 % flammable 720 /, non-flammable Reduction of the heating output (based on the flammable components): 2.5%. Example 3 Hard coal briquettes (ash content anhydrous 60/0), produced from a mixture of 85.5 parts of briquetting coal and 13 parts of ammonium beech sulphite waste liquor (solids content 50 ° / a), 0.5 part of clay with 30 ° / o A1203, finely ground, 0.5 part quartz flour and 0.5 part sodium tripolyphosphate, heated as in Example 1: Oven test as in Example 1. Composition of the ash: 40 % flammable 60% non-flammable Reduction of the heating power (based on the flammable components): 4 , 3 ° / o. Example 4 Hard coal briquettes (anhydrous ash content 60%), produced from a mixture of 84.8 parts of briquetting coal, 4 parts of calcium beech sulphite liquor (solids content 50%), 9 parts of ammonium beech sulphite waste liquor (solids content 50%) ), 1 part clay with 30 % A1202, finely ground, 0.4 part sodium tripolyphosphate, 0.8 part sodium water glass DAB 6.Heated as in example 1.

Oven test as in Example 1. Composition of the ash: 33 % flammable, 67% non-flammable. Reduction in heating output (based on the flammable components): 3.2%.

Example s hard coal briquettes (ash content anhydrous 60/0), produced from a mixture of 87 parts of briquetting charcoal, 13 parts of ammonium beech sulphite waste liquor (Solids content 50%). Heated as indicated in Example 1. Immersed in a 5% solution of equal parts sodium tripolyphosphate and water glass DAB 6 in Water.

Absorption of the briquettes: 0.4% waterglass, 0.4% sodium tripolyphosphate Oven test as in Example 1. Composition of the ash: 31% flammable, 69% non flammable Reduction of the heating output (based on the flammable components) : 2.9%.

Claims (3)

Claims: 1. Method for increasing fire resistance as well as to improve the surface of hard coal and lignite briquettes, in particular of hard coal briquettes, which are binderless or using known binders are produced, characterized in that sodium tripolyphosphate is the starting material added or applied to the finished briquettes by post-treatment. 2. The method according to claim 1, characterized in that the briquettes with water repellants be treated afterwards. 3. The method according to claim 1, characterized in that Water repellants can also be added to the starting materials.