RU2345118C1 - Peat liquid fuel production method - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention refers to production of liquid fuel applied in local municipal combustion boilers. Described is peat liquid fuel production method involving peat preparation and hydrogenation. According to the invention peat is prepared through making peat pulp of humidity 87-99%, which is thereafter dispersed within 1-10 min. Hydrogenation is actually hydrogen barbotage of peat pulp with platinum or platinum-palladium catalyst added within 5-180 min with dispersion in process. Dispersion and hydrogenation are carried out at temperature 293-450 K° and pressure 1-15 atm. Hydrogenation is followed by pulp precipitation and separation into liquid fuel and unreacted agents. To activate peat pulp, prior to dispersion it is added with alcohol in amount 25-35 vl % and/or 0.1 n NaOH solution in amount 0.01-0.02 wt %.

EFFECT: decrease in power consumption of process of manufacture at 5-10 time and reduction in value.

3 cl, 1 tbl, 1 ex

Description

The invention relates to the production of liquid fuel, which can be used in local municipal fuel boiler units.

A known method of producing liquid fuel from wood (RU, No. 94033296, class C10B 53/02, 1997) by exposing wood waste to a gas-vapor mixture in a generator under a pressure of 0.5-1.0 atm and at a temperature of 150-200 ° FROM. Gasification of wood is carried out until it is completely converted into an organic gas product, which is subsequently purified from sulfur compounds and mixed with the unreacted part of the gas product. After which the mixture is heated to 190-240 ° C and sent to the reactor for contact with the catalyst, which is used as granular oxides of non-ferrous metals (copper, zinc, cobalt, etc.) to produce synthetic fuel vapor (methanol). After condensation and separation of the gas mixture, liquid fuel is isolated from it.

The disadvantage of this method is the multi-stage process, which significantly increases the cost of production.

The prototype of the invention is a method for producing an artificial oil-like substance from plant materials (RU, No. 2217471, class C10G 1/04, 2003), including hydrogenation of materials at a temperature and pressure of supercritical values and subsequent separation of the obtained products, while as plant materials use peat, previously prepared in the form of a peat mixture by drying it to a moisture content of 15%, grinding, followed by calibration on a sieve with a hole diameter of 2 mm and mixing with a catalyst, and peat paste by cm sowing dried and crushed peat with kerosene, fuel oil and an iron catalyst - crushed iron in the ratio of components, wt.%: peat 23.8, kerosene 47.6, fuel oil 23.8 and iron catalyst 4.8. The peat mixture and peat paste were respectively loaded into the pyrolyzer and into the hydrogenator, after which, before the hydrogenation operation, the peat mixture was pyrolyzed at a rate of 6 K / min until the temperature Tmax = 720 K or pressure Pmax = 15 MPa was generated in the pyrolyzer, and the mixture was subjected to pre-heating to a temperature 320K peat paste with chemically active vapor-gas-like products of peat pyrolysis, sent to the hydrogenator at the end of its pyrolysis process, at a rate of 6 K / min until the appearance in the hydrogenator perature Tmax = 720 k and pressure = Pmax 15 MPa, followed by exposure hydrogenation without forced cooling for 25-30 minutes. The process of obtaining an artificial oil-like substance is repeated repeatedly. Each subsequent process was carried out in the presence of residual vapor-gas products of pyrolysis and hydrogenation of the previous process, the discharge of which was carried out when they reached a temperature of 420 K in peat mixture and peat paste, respectively, preheated in autoclaves to a temperature of 320 K.

The disadvantage of this method is the complexity and multi-stage process for producing liquid fuel. In addition, the high temperature and pressure at which the process is carried out significantly complicates it and increases the energy intensity and, as a result, the cost of production.

The basis of the invention is the task of reducing temperature and pressure during the production of liquid fuel, as well as reducing the number of technological operations and reduce the number of components used.

The technical result is to reduce the energy intensity of the production process by 5-10 times and its cost.

The task and the technical result are achieved by the fact that in the method for producing liquid fuel from peat, including preliminary preparation of peat with its subsequent hydrogenation, according to the invention, preliminary preparation of peat is carried out by obtaining peat pulp from it with a humidity of 87-99%, which is then dispersed for 1-10 minutes, and hydrogenation is carried out by bubbling peat pulp with hydrogen in the presence of a platinum or platinum-palladium catalyst for 5-180 minutes, do not stop dispersing it, while dispersing and hydrogenating the pulp is carried out at a temperature of 293-450K and a pressure of 1-15 atm. After hydrogenation, the pulp is defended and it is separated into liquid fuel and into unreacted reagents. To activate peat pulp, alcohol or alcohol-benzene in the amount of 25-35 vol.% And / or 0.1 n is introduced into it before dispersion. NaOH solution in an amount of 0.01-0.02 wt.%.

Humidity of peat pulp - 87-99% is due to the fact that with the indicated range a low viscosity of the suspension is ensured and, thus, favorable conditions are created for its mechanochemical activation and hydrogenation by sparging with hydrogen. With an increase in pulp concentration over 99%, an excess amount of moisture is introduced into the mixture, which further increases the cost of drying, and with a decrease in concentration less than 87%, its viscosity also increases, and therefore, the uniformity of its properties in volume decreases, forming clots.

A pulp dispersion temperature of 293-450K at a pressure of 1-15 atm and a dispersion time of 1-10 min ensures homogenization, activation of peat pulp and an increase in the specific surface of the material.

With a decrease in temperature, pressure and duration of the process, there is no formation of a sufficient number of active centers formed during the dispersion process, which leads to a decrease in the yield of liquid fuel to almost zero.

With increasing values of these parameters, the energy intensity of the process increases significantly and no formation of additional active centers occurs, as evidenced by stabilization or even a slight decrease in product yield at the end of the process.

Hydrogenation of peat pulp by bubbling hydrogen in the presence of a platinum or platinum-palladium catalyst with simultaneous dispersion for 5-180 minutes provides the conditions under which the molecules of aromatic hydrocarbons of peat decompose into smaller molecules (destruction) and a liquid oil-like product is formed. The lack of catalyst does not allow to obtain an oily product. With a decrease in the duration of the process less than 5 minutes, the yield of liquid fuel also decreases, and with an increase in the duration of the process more than 180 minutes, an increase in the yield of the product does not occur due to the complete interaction of the active centers with hydrogen.

The introduction of additional alcohol or alcohol-benzene in an amount of 25-35% (volumetric) into peat pulp ensures the extraction of peat tar substances and their translation into a dissolved state, which improves the conditions of the hydrogenation process and, as a result, increases the yield of the finished product. Introduction to peat pulp an additional 0.1 n. NaOH in an amount of 0.01-0.02% (mass) allows you to increase the degree of activation of peat pulp by creating a neutral or slightly alkaline environment that contributes to the creation of favorable conditions under which the molecules of peat aromatic hydrocarbons decompose into smaller molecules and increase the yield of the product.

The process of obtaining liquid fuel from peat is as follows.

An aqueous peat pulp is prepared with a moisture content of 87-99%, then the resulting pulp is loaded into a dispersant and dispersed at a temperature of 293-450 K ° and a pressure of 1-15 atm for 1-10 minutes. After that, the prepared peat pulp is loaded into a reactor in which it is hydrogenated by sparging with hydrogen and in the presence of a platinum or platinum-palladium catalyst with simultaneous dispersion for 5-180 minutes. After the process is over, the pulp is defended and the unreacted residues of peat, moisture and oil-like substance are separated.

To activate the process, before dispersion, alcohol or alcohol-benzene is introduced into peat pulp in an amount of 25-35% (volume) and 0.1 N NaOH solution in an amount of 0.01-0.02% (mass).

Example 1. Prepare 100 kg of 87% aqueous peat pulp, after which it is dispersed for 10 minutes at a temperature of 450K and a pressure of 15 atm. Next, the pulp is placed in a reactor in which the platinum catalyst is loaded, the reactor is closed with a lid and hydrogen is bubbled through the pulp with simultaneous dispersion for 5 minutes. After the process is over, the pulp is defended and the unreacted residues of peat, moisture and oil-like substance are separated. The yield of oil-like product was 69% of the dry matter of peat.

A method for producing liquid fuel from peat is not limited to one example. So, in the framework of the present invention, other examples of the production of liquid fuel from peat are carried out, the results of which are presented in the table.

The main parameters for producing liquid fuel. No. The composition of peat pulp,% Pulp processing mode The output of liquid fuel,% SVT Peat, % Water% Alcohol,% by weight of the pulp NaOH (0.1 N),% by weight of the pulp catalyst temperature, K pressure, atm duration of mechanochemical processing, min hydrogenation time, hour one one 99 0 0 platinum 328 5 one 1.00 fifty platinum palladium 2 5 95 0 0 273 one 5 2,50 69 3 13 87 0 0 platinum 450 fifteen 10 3.00 69 platinum palladium four one 99 1,0 0 328 5 one 1.00 51 5 5 95 5,6 0 platinum 273 one 5 2.00 70 platinum palladium 6 13 87 17.6 0 450 fifteen 10 3.0 76.5 7 one 99 1,0 0.002 platinum 328 5 one 0.75 56 platinum 8 5 95 5,6 0.01 palladium 273 one 5 1,50 77 platinum 9 13 87 17.6 0.05 palladium 450 fifteen 10 3.00 77.5

The invention allows to obtain a liquid oil-like substance, which can be subjected to further chemical processing, to produce hydrocarbons or direct combustion in boilers for thermal energy.

This invention is currently at the stage of experimental laboratory tests.

Claims (3)

1. A method of producing liquid fuel from peat, including preliminary preparation of peat with its subsequent hydrogenation, characterized in that the preliminary preparation of peat is carried out by obtaining peat pulp from it with a moisture content of 87-99%, which is then dispersed for 1-10 minutes, and hydrogenation carried out by barbation of peat pulp with hydrogen in the presence of a platinum or platinum-palladium catalyst for 5-180 minutes, without stopping its dispersion, while the dispersion and hydrogenation are carried out at a temperature of 293-450 K ° and a pressure of 1-15 atm, after hydrogenation, the pulp is defended and it is separated into liquid fuel and into unreacted reagents. 2. The method according to claim 1, characterized in that alcohol is introduced into the peat pulp before dispersing in an amount of 25-35 vol.%. 3. The method according to claim 1, characterized in that 0.1 n is introduced into the peat pulp before dispersing. NaOH solution in an amount of 0.01-0.02 wt.%.