RU2214445C2 - Two-step method for preparing coal-water fuel - Google Patents

Abstract

FIELD: alternative fuels. SUBSTANCE: method envisages preliminarily crushing and classifying coal. Coal with particle size no greater than 3 mm and water are introduced into vertical multichamber vibratory-wave mill with driven element amplitude 1-6 mm and rotation speed 1400-2000 rpm. Further crushing and homogenizing of mixture of coal with average particle size 300 mcm and maximum size up to 500 mcm with water and reagent is continued in horizontal vibratory-wave tore mixer-homogenizer with vertical driven element amplitude 1-4 mm, horizontal driven element amplitude 1-6 mm, and rotation speed 1400-2000 rpm. Advantageously, process is effected on mill with the weight of grinding bodies up to 1500 kg and their diameter 15 to 50 mm and in mixer-homogenizer with the weight of grinding bodies up to 2000 kg and their diameter 10 to 40 mm. Fuel can be used in coal industry and power engineering. EFFECT: significantly lowered power consumption: no more than 25 kW per 1 t coal-water fuel. 3 cl, 3 ex

Description

 The invention relates to methods for the preparation of water-coal fuel (HLF) for its subsequent combustion and can be used in the coal industry and energy.

 A known method of producing a high-temperature fuel cell by multistage grinding of raw or enriched coal. Grinding is carried out in the presence of a reagent. At the 1st stage, grinding is carried out in roller crushers, at the 2nd stage, rod drum crushers are used, at the 3rd - tube vibratory crushers with rods and at the 4th - crushers with balls. Suspension is recirculated at one or more stages of grinding. The reagent is introduced before the individual stages of grinding as the disclosure of a new surface (application Germany 3509330, C 10 L 1/32, 09/25/86).

 Closer to this invention, in essence, is a method for two-stage preparation of HFM, including preliminary coarse grinding and classification of coal, feeding classified coal and water to a ball mill, followed by additional grinding and homogenization of a mixture of coal and water particles together with the reagent in a second ball mill (Japanese application 63-15893, C 10 L 1/32, 01.22.88).

 The disadvantages of the known methods are high energy consumption.

 The aim of this invention is to reduce energy consumption.

 This goal is achieved by a two-stage preparation of HFM, including preliminary coarse grinding and classification of coal, supply of classified coal with a particle size of not more than 3 mm and water into a vibration-wave multi-chamber mill with an amplitude of the working body of 1-6 mm and a frequency of rotation of 1400-2000 rpm / min, followed by additional grinding and homogenization of a coal mixture with an average particle size of 300 μm and a maximum particle size of up to 500 μm, water and reagent in a horizontal mixer-homogenizer vibrats ion-wave torus with an amplitude of a vertical working body of 1-4 mm, horizontal - 1-6 mm and a frequency of rotation of 1400-2000 rpm Preferably, the process is conducted in a mill with a mass of grinding bodies up to 1500 kg and their diameter from 15 to 50 mm and a homogenizer-mixer with a mass of grinding bodies up to 2000 kg and their diameter from 10 to 40 mm.

 The method allows you to spend on the production of 1 ton of fuel-efficiency device no more than 25 kW of electricity.

 Below are examples illustrating the achievement of the goal.

Example 1
The feedstock is ordinary coal of the SSR brand (working moisture 9%, ash content 16%, sulfur content 0.2%) with a grain size of 0.3-250 mm from a coal warehouse through a conveyor feed into a hammer mill. From the crusher, crushed coal with a particle size of up to 6 mm is sent to a vibrating sifter, where coal with a particle size of up to 6 mm is separated and the vibratory vertical multi-chamber (first grinding stage) is fed through a vibrating feeder to the mill. Mill operating mode: rotation frequency of 1450 rpm, the amplitude of the oscillation of the working body 5 mm Ball loading: 1st chamber - balls 50 mm - 250 kg; 2nd chamber - 40 mm - 100 kg; 30 mm - 150 kg; 3rd chamber 30 mm - 100 kg, 23 mm - 150 kg; 4th chamber - 30 mm - 250 kg; 5th - camera 30 mm - 125 kg, 15 mm - 125 kg. When passing crushed coal through a vibratory feeder, the coal is moistened with water to a moisture content of 45%. After a vertical vibratory mill, a water-coal suspension with an average particle size of 300 μm and a maximum size of 500 μm is sent to a vibration-wave torus mixer-homogenizer, where the second stage of grinding and preparation of coal-water fuel occurs with a reagent (plasticizer). The mode of operation of the mixer-homogenizer: rotation speed 1850 rpm, the amplitude of the oscillation is vertical 3.5 mm, horizontal 4 mm. Ball load: 10 mm - 200 kg, 23 mm - 750 kg, 30 mm - 800 kg, 40 mm - 200 kg. After the homogenizer mixer, 55% water-coal fuel with an average particle size of 30 μm is obtained. The energy consumption for the preparation of 1 ton of HLW amounted to 24.5 kW.

Example 2
Used coal composition, which is shown in example 1. The sequence of technological operations is the same as in example 1. The operating mode of the vibration-wave multi-chamber vertical mill: the amplitude of the working body is 1 mm, the rotational speed of 1400 rpm The operating mode of the horizontal mixer-homogenizer of the vibrational wave torus: the amplitude of the vertical working body 4 mm, horizontal 6 mm Rotational speed 2000 rpm Get 55% water-coal fuel with an average particle size of 32 microns. Energy consumption per 1 ton of fuel-and-chemical fuel is 24.9 kW.

Example 3
The coal composition is used, which is shown in example 1. The sequence of technological operations is the same as in example 1. The operating mode of the vibration-wave multi-chamber vertical mill: the amplitude of the working body is 6 mm, the rotational speed is 2000 rpm. The operating mode of the horizontal mixer-homogenizer of the vibrational wave torus: the amplitude of the vertical working body 1 mm, horizontal 1 mm Rotational speed 1400 rpm. Get 55% water-coal fuel with an average particle size of 29.5 microns. Energy consumption per 1 ton of fuel-and-chemical fuel is 23.8 kW.

Claims (3)

 1. A method of two-stage preparation of coal-water fuel, including preliminary coarse grinding and classification of coal, supply of classified coal and water to the mill, followed by additional grinding and homogenization of a mixture of particles of coal and water together with a reagent, characterized in that the classified coal with a particle size of not more than 3 mm and water is fed into a vibration-wave multi-chamber vertical mill with an amplitude of the working body of 1-6 mm and a frequency of rotation of 1400-2000 rpm and additional grinding and homogenization of a coal mixture with an average particle size of 300 μm and a maximum particle size of up to 500 μm, water and reagent is carried out in a horizontal vibration-wave torus mixer-homogenizer with amplitudes of a vertical working body of 1-4 mm, horizontal 1-6 mm and its rotation frequency 1400-2000 rpm.  2. The method according to p. 1, characterized in that the process is conducted in a mill with a mass of grinding media up to 1500 kg and their diameter from 15 to 50 mm.  3. The method according to PP.1 and 2, characterized in that the process is carried out in a homogenizing mixer with a mass of grinding media up to 2000 kg and a diameter of 10 to 40 mm.