Patent Application
20050217423
1. Field of the Invention
The present invention relates to method for cleaning a furnace residue, and more particularly to a residue cleaning method using water to remove lime powder from the residue and recycle the used water to preserve the environment.
2. Description of Related Art
Residue in an iron smelting furnace may be processed to increase the economic efficiency for the business. A complete cycle post-treatment of the residue includes four processes, namely the residue pre-treatment process, the residue processing process, the residue curing process and the residue refining process. However, not each process is adopted by the operator in the business. The four processes are more or less modified to meet different requirements. The focus of this invention aims at the residue processing process. The purpose of residue processing process is to crush the residue, select the available residue, categorize the selected residue and select the residue containing steel over 55% in weight for further processing, such as sintering. The selected residue may be applied as additives for steel refining, cement or even for road engineering or landscape construction.
The conventional residue processing method is divided into the following two different methods.
With reference to
Further, a lot of additives are required during the steel processing period. The additives normally contain a large amount of lime which has a pH value between 10˜11. Thus when the selected residue is used in road construction, the alkaline nature seriously contaminates the environment. Other residue not fully recovered for further application is a waste of material.
With reference to
Although the second conventional method does meet the requirement to separate the lime powder and the residue, the method still suffers from the following several problems:
expense: In addition to the cost of the installation of the drying machine, the lime powder suspended in the air requires an air filtering machine to filter the air so that the total cost is high.
low efficiency: because the process requires the entire residue to be fully dried for further processing, the amount of the residue material to be dried can not be too much, otherwise, the entire process will be delayed and therefore lead to a low efficiency.
air pollution: Even with the use of the air filtering machine, the dust in the air is only reduced and can not be eliminated entirely.
high maintenance cost: The maintenance, operation and repair of all the machinery require a large amount of capital to keep everything in order.
To overcome the shortcomings, the present invention tends to provide a method to mitigate the aforementioned problems.
The primary objective of the present invention is to provide a method to use water to clean the residue of a furnace so that the lime powder and the residue from the furnace are separated.
Another objective of the present invention is that the used water produced from washing away the lime powder from the residue from the furnace is recycled such that the lime powder is able to be collected.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
With reference to
After the residue is selected and categorized into the aforementioned four classes, the residue of different sizes is sent to different magnetic selection devices (41,42,43,44) for selection of residue containing different amounts of iron therein. The 12˜30 mm class is divided into two subclasses for building construction material and road construction material. The 8˜12 mm class may be applied for use as building construction material.
The residue with a dimension under 8 mm is sent to a sand separation device (5) to filter out the sand contained in the water. The filtered-out sand is able to be supplied as a material for sidewalk slabs or bricks. The water passing through the sand separation device (5) flows to the deposition tank (3) for deposition of both sand and lime. The deposited sand and lime may be applied for other applications at a later time. During the deposition of the lime and the sand, the water is collected in a water tank (7) and then recycled to the sprinkling system of the screening device (2) for reuse.
The residue with a dimension above 30 mm is sent to a crushing device (6) to minimize the size of the residue and then the minimized residue passes through a different magnetic device (45) for selection of residue containing iron. Thereafter, the residue is sent to a second container (11) for collection and to a grinding device (7) for grinding. After passing through the grinding device (7), the residue is sent back to the container (1) to repeat the previous steps.
After the description, it is noted that the method of the present invention has the following advantages:
dust prevention: Because the residue is collected in the container and the water in the screening device (2) washes away the lime powder, dust such as lime powder is eliminated and thus surrounding air is clean.
full recycling: After the washing process, the lime powder is collected and deposited in the deposition tank (3), thus the lime may be collected for use as cement ingredient.
environmental protection: Due to the removal of lime powder from the residue, the residue used for road construction is safe for application to the ground and thus the environment is protected from contamination.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
