Solid material comminution or disintegration – Processes – With application of fluid or lubricant material
Reexamination Certificate
1999-10-21
2002-06-11
Rosenbaum, Mark (Department: 3725)
Solid material comminution or disintegration
Processes
With application of fluid or lubricant material
C241S029000
Reexamination Certificate
active
06402064
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for finely granulating granular substances with pollutants such as incinerated ashes adhered.
The present invention relates to a method for carrying out fine granulation of granulating granular substances with pollutants such as soils contaminated by heavy metals, oily constituents and the like adhered and incinerated ashes conveyed from through flying incinerator and also carrying out separation of granular substances without containing pollutants or granular substances, from which most of the pollutants are removed, from the granular substances which are subjected to fine granulation treatment mentioned as above.
2. Description of the Prior Art
Hitherto, unrecycable inflammable substances such as unrecycable raw garbages have been burnt up through a stoker type or fluidized bed type incinerator and the burnt up ashes have been transferred as incinerated ashes to a disposal plant.
In actual incinerated ashes, burnt up scraped metal, fragments of burnt up scraped metals, potteries or earth and sand those of which are burnt up being mixed in the inflammable substances as mentioned above are contained, and consequently in the constituents of incinerated ashes various kinds of metals, silica, alumina and lime are mixed. Since this sort of incinerated ashes are large in scraped volume and are adhered with noxious materials such as heavy metals and dioxin class substances and the like, which are produced during the incineration process, establishment of a technology for method of reduction of volume of the incinerated ashes, rendering the same to be non-noxious or recycling the same.
A method for reducing the noxious heavy metals such as lead, zinc, copper and cadmium to unnoxious following methods are enumerated: (1) solidification through fusion, (2) solidification by cement, (3) treatment by agent, (4) stabilization by acid or other solvent, (5) treatment by carbonation and (6) washing by water. Among those, the surest method is the solidification through fusion of (1) and this method is to scrap the incinerated ashes to a disposal plant or recycle them as extra minute fragments of grains after fusion at a high temperature exceeding 150° C. and today this method is put to practical use. In this method, even when the fused substances contact with water, elution of heavy metals mentioned as above is not said to happen because the heavy metals are trapped within the fused substances.
Since in the method 2 of solidification by cement, the cement is mixed in the incinerated ashes, there exists a fatal disadvantage that the volume of the incinerated substances increases. Further, alkaline of the incinerated ashes, which are subjected to mixing cement in them, is intensified and hence risk of elution of lead and the like is rather built up. In the method 3 of treatment by agent, a pH adjustment is important and still, due to the reason that kinds of substances contained in the incinerated ashes are varied and not to be fixed, pH adjustment is not easy and addition of agent is supposed not to be effective when the pH adjustment is not carried out adequately. In the method 4 of stabilization by acid or other solvent, because the stabilization is carried out in a condition with heavy metals remained, it is hard to prevent heavy metals from elution in long term. In the method 5 of treatment by carbonation, maintenance control of the plant is hard and further equipments are complicated and hence this method is not practical. In the method 6 of washing by water, it is supposed that removal of heavy metals are carried out relatively easily if the environment is not acidified by acid rain but the effect of the method is merely assured by flying ashes in the powder state. Consequently, in this method sufficient effect can not be anticipated for the heavy metals and dioxin class substances adhered to granular substances in a massed granular state.
Also the aforementioned method of solidification through fusion allows reducing dioxin class substances to be unnoxious by thermal discomposition by virtue of a high temperature of treatment of the incinerated ashes, in view of the present situation it is said that this method of solidification through fusion is most effectual and hence this method bears main stream among various method.
However, in view of considerations over a long period of time, in the solidification through fusion too, the possibility of elution of heavy metals trapped within the fused substances buried in the disposal plant can not be denied. Further, there gives rise problems such that construction cost of the facilities and treatment cost are high because large facilities such as incinerating furnace and a large quantity of fuel are required for the solidification through fusion due to high temperature for fusing incinerated ashes.
On the other hand, in recent years, there gives rise to a problem such that soils in the vicinity of chemical factories and metal refineries are contaminated by heavy metals, organic chlorine or oily constituents. Also beach shore soils contaminated by crude oil being effluent to ocean because of disasters at sea and also crude oil adheres to the drug out soils which are conveyed through a tunnel digging of a land subsidence at the area of crude oil deposited and consequently the treatment of such soils becomes hard frequently. Further, the soils with pollutants in questions adhered (contaminated soils) include the soils which are contaminated by mixing aforementioned incinerated ashes into them.
As to soils contaminated mentioned as above too, establishment of a technology for removing aforementioned pollutants and for recycling stones, sands and extra minute grains contained in the contaminated soils after extracting them is anticipated.
Generally speaking, it is said that dioxin class substances adhered to the incinerated ashes sticks to relatively strongly to the surfaces of granular substances with diameters below 2 mm in the incinerated ashes. Then, upon classifying granular substances with diameters more than 5 mm from the incinerated ashes, carrying out treatment for removing dioxin class substances adhered relatively weakly to the aforementioned surfaces, those granular substances are supposed to be unnoxious and allowable to be recycled. In spite of such a situation, as far as the inventor of the present invention is concerned, no methods are proposed for separating the incinerated ashes in a state of massed granular substances to individual granular substances without crushing them and also detaching the dioxin class substances from the granular substances below 2 mm to which dioxin class substances is said to stick relatively strongly.
Also since the incinerated ashes are formed of a soft texture, it is not only hard to detach dioxin class substances adhered to them by means of an usual crushing machine but it is not possible to do so because, if the incinerated ashes are crushed by crushing machine, for example a ball mill, the granular substances of the incinerated ashes are also granulated and thus the granular substances with dioxin class substances adhered can not be separated and, on the contrary, reduction of their volume becomes hard.
In the contaminated soils, though the portions where the granular substances mutually constituting soil grains become to a massed granular state are limited, likewise the aforementioned incinerated ashes, not only detachment of pollutants as above by means of an usual crushing machine is hard but also soil grains in the contaminated soils too are reduced to be granulated because the diameters of pollutants such as heavy metals and oily constituents are extremely small; thus separation of those pollutants are hard.
On the other hand, Japanese Laid-Open Patent Application No. 8-164363 discloses a crushing machine
10
for removing acute angle portions of stones and the like in the dredged soils without crushing dredged soils containing sands, gravels and clays and also for crushing the clods of solids, sand
Ito Yo
Kawaguchi Kenji
Shibata Hirohiko
Shida Yutaka
Tango Takao
Rosenbaum Mark
Shinroku Seiki Kabushiki Kaisha
Wolf Greenfield & Sacks P.C.
LandOfFree
Method and system for carrying out treatment of granular... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and system for carrying out treatment of granular..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and system for carrying out treatment of granular... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2947605