JPH11101423A - Method of treating boiler combustion ash - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively use energy possessed by a liquid fuel in order to treat waste and reduce operation cost of a boiler, by granulating and drying combustion ash produced by a boiler so as to form solid bodies, and charging the solid bodies into a boiler in which solid fuel is burned so as to effect recombustion. SOLUTION: Collected crude heavy oil ash 4 is conveyed to a solidification treatment device 6, water 7 is added in a granulater 8, kneading and granulation are carried out, and the crude heavy oil ash is conveyed to a drier 9 so as to form hard granular bodies. Solid fuel comprising the crude heavy oil ash is conveyed to a position where a coal fired boiler 13 is installed and is fed together with coal as fuel to a banker 11 and is fed from the banker 11 to a mill 12 so as to be crushed and fed to the coal fired boiler 13 and burned. When combustion is carried out in a combustion facility such as the coal fired boiler 13 which uses solid matter as fuel is employed, only a slight modification of equipment enables inclusion of the solid matter into fuel combustion system so as to effect combustion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating powdery combustion ash generated from a boiler for burning liquid fuel such as heavy oil or crude oil.

[0002]

2. Description of the Related Art Powdery combustion ash is generated from a boiler that burns heavy oil or crude oil. Conventionally, this combustion ash has been volume-reduced (valuable) in waste incinerators, and partly according to the "Law on the Treatment and Cleaning of Waste".
It is disposed of as industrial waste and is not reused as fuel.

[0003] This combustion ash is 2,000 kg / kg.
It has a calorific value of up to 6,000 kcal, and it is not preferable to dispose of this as industrial waste from the viewpoint of effective use of resources and the problem of waste disposal. Further, unless the combustion ash having such a large calorific value is effectively used, the operating cost of the boiler for burning the liquid fuel increases, which is a problem.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of recycling combustion ash generated from a boiler for burning a liquid fuel such as heavy oil or crude oil in view of the state of the prior art. .

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is to granulate and dry a combustion ash generated from a boiler for burning a liquid fuel, and to convert the ash into a solid fuel. A method for treating boiler combustion ash, wherein the ash is supplied to a boiler for burning and then reburned.

[0006] The combustion ash generated from a boiler for burning heavy oil, crude oil and the like has a very low specific gravity of about 0.1 and is in a fine powder form, so that it is difficult to handle the ash.

In the present invention, the combustion ash is granulated by an appropriate method such as adding water or the like to the combustion ash and kneading the mixture. As described above, this is dried to form a solid, which is put into a boiler for burning a solid fuel such as a coal-fired boiler and used simply and effectively as fuel.

As described above, according to the boiler combustion ash treatment method of the present invention, the resources contained in the combustion ash can be effectively used, and at the same time, the problem of waste disposal can be mitigated.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for treating boiler combustion ash according to the present invention will be described in detail with reference to an embodiment shown in FIG. In FIG. 1, 1 is a heavy crude oil boiler for burning heavy oil or crude oil, 2 is an air preheater, 3 is an electric precipitator, and collects combustion ash 4 and the like from the combustion exhaust gas.

Reference numeral 6 denotes a solidification treatment device, which includes a granulating device 8 and a drying device 9. A hopper 10 receives the solidified combustion ash. Reference numeral 12 denotes a mill, which receives a supply of solid fuel obtained by solidifying the combustion ash and coal from the bunker 11, crushes and mixes them. Reference numeral 13 denotes a coal-fired boiler, 14 denotes a denitration device, 15 denotes an air preheater, and 16 denotes an electric dust collector.

In the system shown in FIG. 1, heavy crude oil is supplied to heavy crude oil-fired boiler 1 as fuel, and the combustion exhaust gas is led to electric precipitator 3 after heat recovery in air preheater 2.

In the electric dust collector 3, heavy crude oil ash 4, which is combustion ash, is collected from the combustion exhaust gas and collected in the hopper 5. The collected heavy crude oil ash 4 is sent to a solidification treatment device 6, and first, water 7 is added to a granulating device 8 to knead and knead the mixture.
Granulation is performed. The granulated heavy crude ash is sent to the drying device 9 to be hard and small solids.

As described above, in order to solidify the combustion ash, water is added to the combustion ash “1” by “0.2 to 0.4”.
(Weight ratio) After addition and kneading at the ratio of (weight ratio), it was easily formed into small lumps by granulation with a granulator, and further passed through a drying process, resulting in a fine powder having a specific gravity of about 0.1. Ash becomes lumps with specific gravity of 0.5-0.6, and capacity is 1/5
The volume can be reduced to the extent and handling becomes easy.

The solid fuel composed of heavy crude ash obtained in the above steps is transported to a place where the coal-fired boiler 13 is installed. The solid fuel is supplied to the bunker 11 together with the coal serving as the fuel for the coal-fired boiler 13, supplied from the bunker 11 to the mill 12, pulverized, supplied to the coal-fired boiler 13, and burned.

[0015] If the combustion ash is to be reused in a boiler that uses heavy oil, crude oil, or the like as a fuel, the fuel combustion equipment must be largely remodeled. In contrast,
As described above, burning with a combustion facility using solid matter as a fuel, such as a coal-fired boiler, can be easily mixed into a fuel consuming system and burned with slight equipment modification.

The combustion exhaust gas from the coal-fired boiler 13 is discharged outside through a denitration device 14, an air preheater 15, and an electric dust collector 16.

As described above, the present invention has been specifically described based on the illustrated embodiments. However, the present invention is not limited to these embodiments, and specific structures within the scope of the present invention are set forth in the appended claims. Needless to say, various changes may be made to the configuration.

For example, in the above embodiment, solids obtained by granulating and drying combustion ash generated from a boiler for burning liquid fuel are used as fuel for a coal-fired boiler, but this is not limited to a coal-fired boiler. Instead, the boiler may use another solid fuel.

[0019]

As described above, the method for treating boiler combustion ash according to the present invention comprises the steps of:
Since it is dried to be a solid, handling becomes easy.

Since the obtained solid is burned in a boiler for burning solid fuel, mixing with the fuel of the boiler is extremely easy, and the existing equipment can be effectively used.

As described above, according to the method for treating boiler combustion ash of the present invention, it is possible to effectively utilize the energy of liquid fuel, alleviate the waste disposal problem, and reduce the operating cost of the boiler. Can be.

[Brief description of the drawings]

FIG. 1 is a system diagram of a boiler combustion ash treatment system showing one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heavy crude oil boiler 2 Air preheater 3 Electric dust collector 4 Heavy crude ash 5 Hopper 6 Solidification processing apparatus 7 Water 8 Granulation apparatus 9 Drying apparatus 10 Hopper 11 Bunker 12 Mill 13 Coal fired boiler 14 Denitration apparatus 15 Air preheater 16 Electric dust collector

Continuing from the front page (72) Inventor Ishimura Yasunobu 853 Kitagawa, Saijo-shi, Ehime Prefecture Shikoku Electric Power Company Saijo Power Plant (72) Inventor Mitsunori Izumi 2 Sakaide-city Banshu-cho, Kagawa Prefecture Shikoku Electric Power Company Sakaide Power Plant (72) Inventor Shoji Ono 2 Bannoshu-cho, Sakaide-shi, Kagawa Prefecture Inside Sakaide Power Station of Shikoku Electric Power Company (72) Inventor Yukinobu No. 2-5 Marunouchi, Takamatsu-shi, Kagawa Prefecture Inside Shikoku Electric Power Company (72) Inventor Daisuke Nishiura Kobe 1-1-1, Wadazakicho, Hyogo-ku, Yokohama

Claims (1)

[Claims] 1. A combustion product ash generated from a boiler for burning liquid fuel is granulated and dried to form a solid, and the solid is put into a boiler for burning solid fuel and re-burned. To treat boiler combustion ash.