Mixed fuel

FIELD: power industry.

SUBSTANCE: mixed fuel includes lignin and hydrogen in the weight ratio of lignin to hydrogen of 9:1 to 1:9, mainly of 2:1 to 1:3.

EFFECT: more complete combustion of lignin; reduction of ash content of fuel.

1 cl


The invention is intended for use in the fuel and energy sector, in particular to improve the properties of the lignin used as fuel. The goal is achieved by introducing into a flame of hydrogen gas, promoting more complete combustion of lignin, increased heat transfer, due to the high thermal conductivity of hydrogen and the product of its combustion is water vapor, which reduces the heat loss, reducing harmful components in the combustion products and, consequently, reducing pressure on the environment [1].

Lignin is not made on purpose. Lignin and its chemically modified forms are waste timber production, are formed in the implementation of a number of technologies of wood processing and often in large quantities accumulate in the plant dumps, polluting the environment. Wide application of lignin is not yet found. This substance serves as a raw material for producing granular activated carbon, porous bricks, fertilizers, fillers, plastics and others, but more often than boiler fuel in the same factories where it was obtained. Lignin has a calorific value, which is for absolutely dry lignin 5500-6500 kcal/kg for the product with 18-25%humidity 4400-4800 kcal/kg, for lignin with 65%humidity 1500-1650 kcal/kg

The structure of the hydrolysis leagues who John is a well-developed system of micro - and macropores, what contributes to the retention of large amounts of water. This water will attempt to remove or its content be reduced to a minimum to increase the calorific value of lignin [2].

The number of known ways of using lignin as fuel.

In the simplest cases, lignin milled, dried and burned in a special boiler, dried in the pipe-drying to a residual moisture content of 35-40%, and then burn or dry, and then bitteroot or granularit. The first method is time-consuming and complicated in hardware design, the second is complex, explosive and significant emissions of lignin in the atmosphere, and the third (as the first two) - the need for energy costs for drying and briquetting[3, 4, 5].

A method of obtaining fuel pellets [5], in which the lignin and(or) the cellulose material with humidity of about 55% by weight is mixed with calcium carbonate and dried in the dryers to 5-15% moisture, and then add in 1-10% of a suitable thermoplastic material (paraffin GAC, paraffins, lignosulfonates and others) and granularit at a temperature of not less than 95°C. To increase the calorific value of the fuel mixture can be added shredded tyres, thermosetting resin and(or) waste oil refining industry. It is obvious that this method, as mentioned above, blade the same disadvantages: the necessity of pre-drying the lignin and complexity of instrumentation.

The number of known ways, including a combination of lignins before burning with a pasty or liquid industrial waste and oil sludge, tar, termoisola, extracts oil production, oil or kovovymi residues and organic waste industries[3, 4, 5, 6].

All the above methods have the common disadvantage that require delivery of lignin to the place where suitable waste production, or delivery of this waste to the place where there is accumulation of lignin and the need for its use as an energy source. Almost all methods use lignin as fuel associated with the preliminary drying of lignin, requiring energy costs and the related equipment.

It is known that waste of a number of biotechnological productions associated with the processing of plant matter, is as lignin and hydrogen gas with a high calorific value [7, 8].

When the butanol biosynthesis, for example, from sugars derived from waste wood, 20-30% by weight of this wood goes into the blade in the form of saturated water, lignin, and identifies hydrogen gas. From 1 ton A.S. wood by the method of enzymatic hydrolysis get 600 kg of sugar, 400 kg of lignin, and after further biotransformation chem and 210 liters of butanol, and 380 kg of gases, of which 97% CO2and 3% N2(368 kg of carbon dioxide and 12 kg of hydrogen).

Well-known difficulties of storing and transporting hydrogen in most cases make appropriate use of the resulting "biohydrogen" for internal needs of the production, in particular to generate heat by burning together with lignin.

A method of obtaining fuel from biomass under pressure and at high temperature in an atmosphere of various gases like nitrogen, carbon dioxide or inert gases, including hydrogen, which is used to create an oxygen-free atmosphere developed in the 30s of the 20th century the Fischer-Tropsch process to produce liquid fuels for internal combustion engines. Gases to create an oxygen-free atmosphere included in the received fuel in proportion to their very low solubilities, and, of course, their influence on the properties of the resulting product is negligible. Such a product cannot be considered a combined fuel biomass, including lignin with hydrogen, or would have had to consider those and fuel obtained also in the atmosphere of nitrogen, carbon dioxide or inert gases, prevent oxidation, one of which is the burning of fuel in an atmosphere of oxygen [9]. Thus, the above-mentioned patent may not RA smotriatsa as an analogue of the claimed invention.

The invention aims at eliminating the fuel production process is the stage of drying the lignin, the use of other waste requiring transport to the place of disposal, increasing the calorific value of one of the waste products of lignin due to its co-incineration with other waste that production of gaseous hydrogen and simplified apparatus registration process, consisting in the use of burners known designs with minor technical improvements (see coal-water fuel).

The closest prototype of the same purposes of the claimed invention, the essential features are lignin wet grinding, turning it into an analogue of the coal-water slurry [1] and burned in a specially designed burner and fuel from lignin [5], which is a mixture of lignin from waste oil.

Disadvantages prototypes are low calorific value fuel, the need for pre-drying the lignin, the necessity of its mixing with other substances requiring delivery to the source of the lignin, increased ash content.

Technical results of the invention are the elimination of the fuel production process stage drying of lignin, it Pach is the use of solid or liquid waste, requiring transportation to the source of the lignin and the use of simple hardware design of the combustion process, reduced the ash content of the combined fuel, provided the replacement parts lignin with hydrogen, the product of combustion is water vapor.

Technical results achieved by the fact that the lignin and the hydrogen produced on the same production burn-in duplex burners, in which different levels of burn the lignin obtained after wet grinding, and the hydrogen obtained in the same biotechnological process. The mass ratio of lignin and hydrogen range from 9:1 to 1:9, predominantly from 2:1 to 1:3. The calorific value of the combined fuel can be estimated, taking into account the calorific value of lignin, its water content, calorific value of hydrogen and its amount in the composition of the combined fuel.

Thus, the set of distinctive features of the described invention achieves the specified result.

As a result of the analysis of the prior art co-combustion of lignin and similar hydrogen, characterized by signs, identical with all the essential features of the claimed invention, not found, therefore the claimed invention meets the condition of "novelty". Simplicity, n is implemented to date, demonstrates compliance with the present invention, the term "inventive step".

Thus, the above information suggests that the claimed invention is intended for co-combustion of waste biotechnological production of lignin and hydrogen has the above properties. For the claimed device as it is described in the above-mentioned claims, there are no obstacles to its implementation in practice using common and available tools, electronics and automation. Therefore, the claimed invention meets the condition of "industrial applicability".

Sources of information

1. Vinculis PS, Donchenko VK, Skorik SCI Polydisperse and mixed fuels: an environmental and economic aspects. SPb., Publishing house "Ehusbook", 2009, 198 S.

2. Holkin SCI Technology hydrolytic production. - M., "Forest industry", 1989, s-444.

3. EN 2129142 Nizhegorodtsev VI; Nizhegorodtsev SV; Nizhegorodtsev T.V.; Toropova L.V. Way to obtain fuel from lignin. 1996.

4. EN 2147029 Fuel briquette and method of its production. Lori V.G. 1999.

5. WO 79/00988, 29.11.79.

6. N.I. Chernov, Korobkova SO, S.V. Kiselev Biomass as an energy source. Herald of the Russian Academy of natural Sciences, 2010, No. 1, p.54-60.

7. Kondratiev That Is, The., Gogotov I.N. Molecular hydrogen in the metabolism of microorganisms. M.: Nauka, 1981. 342 C.

8. Hakobyan V.B. have been, Sychev A. Hydrogen is a valuable by-product of the production of biobutanol". Alternative energy and ecology. 2009, No. 6, pp.8-12.

9. US 2008/0016752 A1.

Combined fuel comprising lignin and a hydrogen mass ratio of lignin to hydrogen from 9:1 to 1:9, predominantly from 2:1 to 1:3, and characterized by low ash content.


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FIELD: chemistry.

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