JPH058958B2 - - Google Patents

Description

[Detailed description of the invention]

a. Field of Industrial Application The present invention relates to a foaming agent for use in an aqueous suspension of clay minerals, which has excellent foaming properties and excellent foam stability. b. Prior Art Ionic and nonionic surfactants are generally used as foaming agents, and other water-soluble polymeric substances such as protein substances and cellulose may also be used. In general, methods for generating bubbles include a method of generating bubbles by mechanical action, and a method of generating gas by chemical reaction. The foaming agent of the present invention is a substance that generates bubbles by a method using mechanical action and is effective in retaining the bubbles. In particular, after foaming a suspension of clay minerals such as bentonite and mountain clay, it has the effect of stabilizing and maintaining the foam for a long period of time. c Problems to be solved by the invention Conventionally, as a foaming agent for suspensions of clay minerals,
A common surfactant was used. However, over time, the multiple bubbles themselves coalesced and even collapsed, resulting in a lack of long-term stability. Furthermore, under pressure, the bubbles were destroyed and the bubbles were not stable. d. Means for Solving the Problems The present inventors have conducted extensive research in order to obtain a stable aerated fluid that does not cause bubble destruction even after repeated circulation under pressure. As a result, the foaming agent of the present invention was obtained. The foaming agent of the present invention is prepared by adding and mixing 0 to 1 part by weight of a surfactant having a carboxyl group and/or a sulfuric acid group to 1 part by weight of a surfactant having a sulfone group. The aerated foam fluid using the foaming agent according to the present invention has excellent foam stability, does not collapse under pressure, and has excellent flow characteristics. In particular, when a suspension containing clay minerals is foamed using the foaming agent of the present invention, the resulting aerated foam fluid exhibits excellent stability even under pressure changes and has excellent fluidity. Therefore, it can be suitably used as a drilling fluid. Furthermore, when the aerated foam fluid containing clay minerals using the foaming agent of the present invention is used as a drilling fluid, it is easy to separate the excavated soil, and it also has good fluidity and water permeability as a drilling fluid. Excellent suppressive effect. Therefore, when the aerated foam fluid is used as a circulating fluid in an earth pressure shield construction method, it exhibits excellent water-stopping effects and excellent properties in separating excavated soil. Another example of a shield method using a fluid containing bubbles is Japanese Patent Publication No. 47560/1983. but,
Generally, in the earth pressure shield construction method, mud in which mountain clay, bentonite, etc. are appropriately suspended is used as the circulating fluid. When proceeding with shield construction using this mud, there were many problems in the progress of the construction, such as the shield machine becoming sticky and it being difficult to separate the excavated soil from the mud. In such a shield construction method, the aerated foam fluid using the foaming agent of the present invention has excellent flow characteristics, can easily separate excavated soil, has a water-stopping effect, and contains stable bubbles, making it an excellent fluid. It is. Examples of the sulfonic group-containing surfactants of the present invention include polyalkylsulfonic acids, polyalkylbenzenesulfonic acids, naphthalenesulfonic acid formalin condensates, ligninsulfonic acids, petroleum sulfonic acids, and other alkali metal salts of compounds containing sulfonic groups. (Na, K salts, etc.) and ammonium salts. Examples of the carboxyl group-containing surfactant of the present invention include polyacrylic acid, polymethacrylic acid,
Examples include alkali metal salts such as Na and K salts or ammonium salts of other carboxyl group-containing compounds such as polyvinyl acetate, higher fatty acids such as oleic acid and linoleic acid. As the surfactant containing a sulfate group of the present invention, a surfactant containing a sulfate ester can generally be used. For example, lauryl sulfate, polyoxyethylene alkyl ether sulfate,
Polyoxyethylene alkyl phenol ether sulfuric acid, higher alcohol sulfuric esters, and alkali metal salts (such as Na and K salts) or ammonium salts of sulfuric esters can be used. The foaming agent of the present invention contains 0 parts by weight of the above carboxyl group-containing surfactant and/or the above sulfate group-containing surfactant per 1 part by weight of the above sulfone group-containing surfactant. ~1 part by weight was added and mixed. This foaming agent has an excellent foaming effect, the resulting foam is stable against pressure changes, the aerated foam fluid has excellent fluidity, and when used for excavation, excavated soil can be easily separated and stopped. Excellent water effect. e Effect The foaming agent of the present invention has carboxyl groups and/or
Alternatively, 0 to 1 part by weight of a surfactant having a sulfuric acid group is added and mixed. The obtained foaming agent is added, for example, to 100 parts by weight of mud, which is the circulating fluid in the shield method, by adding 0.1 to 100 parts by weight.
A foam-containing fluid can be prepared by adding 2.0 parts by weight and causing foaming. This bubble-containing fluid has excellent fluidity and can be fed with a small pump pressure. This aerated foam fluid has a water-stopping effect that suppresses spring water at the excavation face in the shield method, and also effectively suppresses water in the fluid from escaping into the formation, maintaining the fluid flow characteristics and stabilizing it. Make it something. Further, the circulating fluid for shield construction method foamed with the foaming agent of the present invention has other characteristics such that excavated soil can be easily separated, and the water content of the separated excavated debris is low, making it easy to handle. It is also stable against pollution. f Example [Example 1] 50 parts by weight of mountain clay (produced in Gifu), 16 parts by weight of bentonite (produced in Gunma), and 75 parts by weight of water are sufficiently stirred in a mortar mixer to make mud (referred to as basic mud). . Next, products 1 to 5 of the present invention are prepared as shown in the table below.

【table】

[Table] Invention product 1 was added to the basic mud above at 0, 0.1, 0.4,
0.5 and 1.0 were added, and the mixture was stirred and foamed in a mortar mixer for 10 minutes to obtain an aerated foam fluid. The (1) bubble mixing ratio, (2) fluidity characteristics (clay), and (3) drainage volume (in ml used to judge the water-stopping effect) of this aerated foam fluid were measured.

[Table] The above commercial product is a sulfuric acid ester salt of lauryl alcohol ether, which is commercially available as a foaming agent from Nissin Rika Sangyo Co., Ltd.

【table】

【table】

[Example 2]

Inventive products 2, 3, 4, 5 were added to the basic mud of Example 1.
0.3% of each was added, and (1) bubble mixing ratio, (2) flow characteristics (viscosity), and (3) drainage amount (10 minutes pressurized mL) were measured.

【table】 [Brief explanation of the drawing]

The drawing is a schematic diagram showing an apparatus for measuring the drainage amount of mud using the foaming agent of the present invention and mud using a commercially available foaming agent. 1... Water layer, 2... Pressurized air supply port, 3... Glass bead layer, 4... Mud and glass bead layer, 5...
Paper, 6... graduated cylinder, 7... container.

Claims (1)

[Claims] 1. A foaming agent for suspensions of clay minerals, which is prepared by adding and mixing 0 to 1 part by weight of a surfactant having a carboxyl group and/or a sulfuric acid group to 1 weight of a surfactant having a sulfone group. .