JPS58205007A - Combustion method of pulverized coke - Google Patents

Abstract

PURPOSE:To permit a pulverized coke, which is regarded as difficult to burn continuously, to be continuously burnt similarly to other fine-quality fuels, by burning the coke in a specific state. CONSTITUTION:A powder coke, which is regarded as relatively difficult to burn continuously, is ground into a pulverized coke so that not smaller than 85% thereof can pass a 100-mesh sieve and the coke has a percentage of free water of not larger than 3%. The pulverized coke is carried into a furnace by means of air, and the temperature therein is maintained above 800 deg.C. The thus pulverized coke is strongly affected by water in physical properties, such as fluidity or the like: the coke changes its falling state from a hopper and fluid state by the carrier air. For this reason, the water content of the coke is controlled so as to be not larger than 3%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of making coke breeze, which has conventionally been considered to be a material of relatively narrow industrial use, such as for sintering iron ore, useful as a high-quality fuel.

Coke powder 7 is generated in large quantities as a by-product during the production and handling of various types of coke, and in recent years in particular, restrictions have been placed on the use of high-quality coal such as strong coking coal, and as a result, the amount of by-product is becoming impossible to ignore.

This means that the burden of energy costs on industry is becoming more serious! In view of the current situation, there is an urgent need to take some kind of improvement measures, and at the same time, there is an urgent need to find new ways to effectively utilize coke breeze.

The present inventor has been involved in the pulverization of coal, the carbonization and cocoonization of coal, and the
We have been conducting research on coal combustion, coal gasification, etc., and recently we have developed a method to crush coke powder, which has been considered relatively difficult to continuously burn, so that more than 85% of it passes through a 100 mesh sieve.
We have discovered that it is possible to burn coke continuously in the same way as other high-quality fuels by converting it into pulverized coke with an adhering moisture content of 3% or less, transporting it into the furnace using air, and maintaining the temperature inside the furnace at 800"C or higher. It is.

In the present invention, pulverizing the coke powder so that it passes 85% or more of 100% of the coke is an essential condition for continuous and rapid combustion. It is used for pulverizing coke and does not require any special measures, but it is preferable to dry it at the same time as pulverizing in order to reduce the moisture content of the pulverized coke to 3% or less. When the moisture content of raw coke powder is high, for example, 5% or more, it is necessary to pre-dry it using a rotary drum dryer or the like before applying it to a pulverizer. More than 85% of water is passed through a 100 Metssie sieve and the moisture content is 3.
It is possible to transport fine coke with dry air and burn it continuously, but in order to control the combustion temperature and operate the furnace smoothly, it is necessary to reduce the particle size of fine coke to 1.
It is particularly preferable that the powder be pulverized to a degree that 98% or more passes through a 0.00 mesh sieve. Coarse coke powder that does not pass through a 100 mesh sieve cannot be fully burned in the furnace, and may remain as unburned carbon in the ash of the combustion residue. It becomes the economy. For this reason, the smaller the amount of coarse coke powder, the better.

In this case, no toxic exhaust gas of carbon monoxide was detected. As long as the proportion of coarse coke that did not pass through the 100 Mesosie sieve was 15% or less, continuous operation of the furnace was not hindered. mosquito< .

When the coke is pulverized as shown in the figure, the moisture content is preferably 2.beta. or less, preferably 1% or less. Originally, a typical inert carbon is coke, but when it is pulverized as in the present invention, its physical properties such as fluidity are strongly affected by moisture, and its falling condition from the hopper and transportation This causes a change in the flow state caused by air. Therefore, in carrying out the present invention, it is still essential to control the water content in coke to 3 g or less.

Note that the transport static electricity used in the present invention needs to be dehumidified as much as possible due to the above-mentioned circumstances. The degree of dehumidification is not restricted in the present invention, but it varies depending on the environment and place where the present invention is implemented, or depending on the temperature.

The present invention will be described in detail below with reference to Examples, but it is obvious from what has been stated in the detailed description of the invention that the present invention should not be limited only to the following Examples.

EXAMPLE Finely pulverized coke is placed on a conveying static electricity from a Roots blower using a rotary valve and is conveyed by air.

The solid-gas mixture of air and coke enters a special burner.
The powder forms a swirling flow from the tip, is sprayed into the furnace, and is combusted by the combustion air.

LPG was used as the pilot and initial heating fuel.

The water equipment uses a scrubber to clean the exhaust gas assembly.

Main equipment specifications ■Furnace body Air jacketed stacking furnace inner diameter
11000φ ■Burner Fine coke, LPG mixed burner capacity LPG MAX 1 o N, 7/h co-px
MAX 100 kq/h ■Transport device Rotary valve 2-stage % type % ■Roots blower u+oNm/h X 30 ㎜mg
% Ingredients Moisture 11%, v, Ml, 0%, Ash 12%
, SQ, 78%, Fixed C87% Combustion Procedure First, LPG is ignited and burned at 1t)Nm% for about 15 minutes. After that, fine coke is transported at 1 o o kq/h A
Input at R10ONrn'/h. Combustion air is 65
0 to 105ONTrVk3. LP() after temperature rise
If the temperature is around the pilot level (3N/h) or if the furnace temperature is too high, the coke will begin to self-combust. The furnace temperature can be set high or low by varying the amount of coke introduced by changing the rotational speed of the rotary valve.

Combustion temperature LPG pie ← at loft 800 ~ 160°C
Self-combustion time 1200~160
Typical composition of 0"C exhaust gas (coke 100 kg/h, conveying air 100N, combustion air 1050 NII//i'I, furnace temperature 1200
"C) N278%, 0280mm, COD, 35chi, Co
213.4% used in this example, and with a special burner and a special conveyor, it can be used as an alternative fuel to heavy oil without any problem.

patent applicant Hiroshima Ganushi 11 Co., Ltd. agent Patent attorney (642[+) Kanji Ida 39-

Claims (1)

[Claims] (11100) Fine coke powder with a water content of 3% or less that has been pulverized so that it passes 85% or more of the 11100 Metssie sieve is sent into the furnace with air, and is continuously combusted at a furnace temperature of 800"C or higher. How to burn coke.