JPS601907B2 - chemical crushing agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chemical crushing agent that can safely and gradually destroy concrete, rocks, etc. without using explosives.

Conventionally, when destroying concrete, rocks, etc. in civil engineering work, etc., explosive demolition using explosives or mechanical demolition using breakers or the like has been carried out.

However, these systems generate noise, vibration, flying stones, dust, gas, etc., and require safety and pollution countermeasures, making them unsuitable for destroying urban buildings or for construction in densely populated residential areas. On the other hand, it has been known for some time that scales that contain quicklime as its main component can statically destroy concrete, rocks, etc. by utilizing the expansion pressure caused by hydration, but the hydration rate of quicklime is very far from that of quicklime. When the slurry expands, it flows out from the crushing holes and the expansion pressure escapes, so it cannot be used as a crushing agent as it is.

As a method to improve this, a method has been proposed to close the entrance of the fracture hole with a rapidly hardening cement or an instrument, but this method is difficult to operate and is not practical.

The present invention was made as a result of research to improve these drawbacks, and the main component composition obtained by firing is Ca0.
Contains 30 to 95 M% of CaF2, and contains CaF2 such that the weight ratio of Ca○/CaF2 is 1 to 80, and Ca0 is CaF2
Its gist is a chemical crushing agent characterized by being coated with That is, the present invention was made based on the knowledge that when the main component is Ca0 and the Ca0 is covered with CaF2, the hydration rate is relatively slow, but the expansion rate is high. The component range of the crushing agent of the present invention is Ca030 to 95 wt%, preferably 45 to 95 wt%.
t%, but if the content of Ca0 is less than 3%, the effect of Ca0 will not be sufficiently exhibited and the expansion pressure necessary for crushing will not be obtained.

Furthermore, if it exceeds 95 wt%, no particularly remarkable increase in expansion pressure is observed, and if it exceeds 95 wt%, cheap quicklime cannot be used as a Ca0 source in terms of purity, making it uneconomical. CaF2 is contained so that the weight ratio of Ca○/CaF2 is 1 to 80. If the ratio is less than 1, it may be combined with other components, but the Ca○ content is relatively low. Since the amount decreases, sufficient expansion pressure cannot be obtained, and the activity of Ca○ is suppressed too much, so that sufficient expansion pressure is not developed.

Further, when the weight ratio of Ca○/CaF2 exceeds 80, sufficient hydration retarding effect is not observed, and when mixed with water, Ca0 hydrates explosively within a short period of time. In addition, in the present invention, SP2, AI203, Fe203, CaS04, etc. are added as auxiliary components to Ca0 in the firing raw material.
When mixed and fired in a range of 20%, the following a○・Si0
2, 3Ca○・Si02, Ca○・AI203, Ca○
・74203, book a○・Fe203, Ca01CaS0
Compounds such as No. 4 are effective in suppressing the hydration of Ca○, and these compounds can be used as appropriate.

The chemical crushing agent of the present invention is prepared by mixing quicklime or calcium carbonate with a fluorine compound (NaF) so that it has a predetermined composition.
, KF, Na3AIF6, AIF3, N is F, HF, N
a2SiF6, etc.), and if necessary, SP2,
It is carried out by mixing AI203, Fe203, and CaS04 in a range of 0 to 20%, firing at 800 to 1400 qo, and pulverizing the fired product.

If the firing temperature is less than 80,000, a sufficient retardation effect cannot be obtained, and if it exceeds 140,000, the hydration retardation effect does not particularly increase, so firing at a temperature of 140,000 or less is sufficient. In addition, in the preparation of the chemical crushing agent of the present invention,
The hydration retardation effect becomes large when the CaF2 production reaction and the Ca◯ hardening effect occur in parallel during firing.

On the other hand, those in which the CaF2 production reaction proceeds at room temperature, such as HF and N ratio F, have little hydration retardation effect, and those in which CaF2 is simply mixed with Ca0 and fired have no hydration retardation effect. However, the deviation is also not desirable. The crushing agent of the present invention is extremely excellent as a crushing agent even with only the main components obtained by firing, but it can be made more practical by adding various auxiliary agents in consideration of the hydration retardation effect and workability. It can be used as a crushing agent.

Specific effective agents include water reducing agents, retention agents, hardening start retardants, etc. Using water reducing agents improves operability, and water reducing agents include lignin-based, higher polyhydric alcohols, etc. sulfonate and its highly condensed compound system, polyol composite system, water-soluble melamine resin system, B-
Various types such as naphthalene sulfonic acid formalin condensate can be used, and the amount added is 0.5 to t.
A range of % is preferred. If it is less than 0.5 M%, no water-reducing effect will occur, and if it is added in excess of t%, the effect will not improve.

Furthermore, although a retaining agent is not necessarily required, adding hydraulic gypsum will quickly harden the gypsum, which will help retain the shape of the crushing agent and retain mixed water.

If the amount of hydraulic gypsum is less than 3%, curing will be insufficient and the added effect will not be achieved.If the amount is too large, it may interfere with the pond component, but the amount of the main component will be relatively small. , about 3 t% or less is preferable. In addition, as hydraulic gypsum, Q-hemihydrate gypsum, 81-hemihydrate gypsum, O-type anhydrous gypsum, etc. can be used, but due to their hydration rate, Q
・It is preferable to use 8-hemihydrate gypsum. In addition, as hardening start retarders, organic carboxylic acids such as citric acid, succinic acid, malic acid, and malonic acid, polysaccharides such as sugar, and phosphates such as sodium tripolyphosphate, sodium pyrophosphate, and calcium phosphate are used. , borax compounds such as borax, copper compounds, amino acids,
One type selected from protein decomposition products or two or more types that can be mixed can be used, and the amount added is 0.01-1. Book t
A range of % is preferred. When actually using the crushing agent of the present invention, it is sufficient to add 30 to 4 parts by weight of water to 10 parts by weight of the crushing agent to form a slurry, inject it into holes drilled in the object to be crushed, and form a static layer. As the hydration of Ca○ progresses and it hardens and expands, the object to be crushed is crushed silently. Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Examples 1 to 8, Comparative Examples 1 and 2 Quicklime (Ca09 skin t%) crushed to 100 mesh pass
) per 100 parts by weight, NaF as a fluorine compound,
Na3NF6, Na2SiF6 and auxiliary components Si02, Yama203, Fe203, and CaS04 were mixed as shown in Table 1, and fired in an electric furnace at 1000o0 for 2 hours to obtain a clinker.

After leaving this material in a desiccator to room temperature,
Got the mesh path thing. X-ray diffraction revealed that no raw material fluorine compounds were present in this product, and that CaF2 was
It was confirmed that it was generated to cover a○. After adding auxiliary agents to this powder as shown in Table 1, it was made into a slurry with a predetermined amount of water, and poured into a concrete soul of 1 × 1 m × 1 kite with a hole of 3 skins ◇ × 40 skins, and its destructive effect was evaluated. Observed. The results are shown in Table 1. Comparative Example 3 Quicklime crushed to 100 mesh pass (Cao9 skin t%
), 15 parts by weight of fluorite (CaF297%) were added and mixed well, and a crushing agent was prepared under the same conditions as in Examples 1 to 8, and the same tests were conducted.

The results are shown in Table 1. omitted holy wings groove S cod ” turtle Pi night S lotus ant 8 Physical writing Thin se embarrassment Small Kaden Key theory Kaoru Hayabusa Yui Mizo - Groove Mizomori smoke twist S too far y cloudy ÷Turtle to 8 state of mind Hy touch Dragon' carp) M* The entry is Ship to.

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Claims (1)

[Claims] 1. The main component composition obtained by firing is 30% of CaO.
~95 wt%, CaF_2 such that the weight ratio of CaO/CaF_2 is 1 to 80, and CaO is CaF
A chemical crushing agent characterized in that it is covered with _2. 2 CaF_2 source becomes CaF by calcination and reaction with CaO
Claim 1, which is a fluorine compound that produces _2
Chemical disruption agents as described in Section. 3 As firing raw materials, SiO_2, Al_2O_3, Fe_2O_3, CaS in an amount of 20 wt% or less based on CaO
The chemical crushing agent according to claim 1 or 2, further comprising O_4. 4. The chemical crushing agent according to any one of claims 1 to 3, wherein a cement water reducing agent is added as an auxiliary agent in an amount of 0.5 to 2 wt%. 5 Hydraulic gypsum is used as an auxiliary retention agent of 3 to 30%
Claim 1: wt%
The chemical crushing agent according to any one of Items 1 to 4. 6 Organic carboxylic acid as an auxiliary curing initiation retardant,
Claim 1: At least one selected from among polysaccharides, phosphates, boron compounds, copper compounds, amino acids, and protein decomposition products is added in an amount of 0.01 to 1.0 wt%. The chemical crushing agent according to any one of Items 5 to 6.