JPH028982B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an invention in which a treatment liquid obtained by treating coal dry distillation gas by the Fumax Rodax method is used as an accelerator for cement compositions, and a water reducing agent composition containing the treatment liquid as a component. It is related to. (Prior Art) In order to promote the strength development of cement compositions (general term for cement paste, mortar, grout, concrete, etc.), it has been common practice to add an accelerator. For example, when performing construction at low temperatures, when demolding is accelerated to speed up the rotation of the formwork, etc.
It is also used in combination with an admixture that has retarding properties to cancel out the retarding properties. Calcium chloride has traditionally been used as an inexpensive and highly effective accelerator, but its use has recently been strictly regulated because it causes rust in the reinforcing bars in reinforced concrete. . Therefore, a so-called non-chloride type accelerator that does not contain chloride is desired in this industry, but the currently proposed non-chloride type accelerator has a balance between price and effectiveness, that is, from the point of view of cost performance, it is better to use calcium chloride. It is unsatisfactory compared to (Problems to be Solved by the Invention) An object of the present invention is to provide a non-chloride type accelerator with good cost performance. It is a further object of the present invention to provide standard or accelerated water reducers that are chloride-free. The present invention has achieved these objects by using a treatment liquid obtained by treating coal dry distilled gas by the Fumax Rodax method as an accelerator. By the way, the above-mentioned processing liquid is industrial waste, and the present invention also aims at the effective use of this industrial waste. (Means for Solving the Invention) The present invention firstly provides an alkali metal-based or alkaline earth metal-based treatment liquid (suspended substances such as free sulfur) obtained by treating coal dry distilled gas by a fumux-rodax method. This is a cement composition characterized by containing 0.02 to 2.0% by weight of cement (based on the weight of cement) in terms of solid content.
(hereinafter referred to as the first invention) Furthermore, secondly, the present invention provides that (a) the above treatment liquid (from which suspended matter has been removed) is 0.05 to 1.0% by weight in terms of solid content (b) based on the weight of cement; 0.01 to 0.25% by weight of lignin sulfonate (c) 0.01 to 0.10% by weight of oxycarboxylate and
A cement composition characterized in that the total of (b) and (c) is 0.05% by weight or more and (d) alkanolamine is contained in an amount of 0.002 to 0.02% by weight. (Hereinafter referred to as the 2nd invention) The above-mentioned fumax-rodax method is a processing method developed in Japan as a processing method for removing harmful substances such as hydrogen sulfide, hydrogen cyanide, and ammonia during dry distillation of coal, and is implemented in various parts of the country. has been done. This is described in the June 1975 issue of the magazine ``Sulfuric Acid and Industry'' published by the Japan Sulfuric Acid Association, pages 9-13, and the summary is as follows. When hydrogen sulfide in coal dry distillation gas is absorbed into an alkaline aqueous solution and then this absorption liquid is brought into contact with air in the presence of an oxidation catalyst (for example, picric acid), hydrogen sulfide is oxidized and sulfur is liberated. This is called the fumatsu process. The liberated sulfur reacts with alkaline substances and hydrogen sulfide in the absorption liquid to form polysulfide salts. On the other hand, hydrogen cyanide in the dry distillation gas exists as a cyanide salt in the absorption liquid, and this reacts with the polysulfide salt to generate rhodan salt. This is called the Rodax method. Thus, hydrogen sulfide and hydrogen cyanide in the dry distilled gas are converted into rhodan salts and removed by the Fumax-Rodax process. Therefore, rhodan salt is present as the main component in the Fumax/Rhodacus treatment solution, but in addition, thiosulfate,
Other by-products are also included. Various alkaline substances such as ammonia, sodium hydroxide, calcium hydroxide, etc. can be used as the alkaline substance in the absorption liquid, and the salt in the treatment liquid accordingly becomes a salt of the alkaline substance. It is called a so-and-so-based processing solution, named after the alkaline substance used. For example, when sodium hydroxide is used, it is called sodium base, and when calcium hydroxide is used, it is called calcium base. usually,
Ammonia is used as the alkaline substance in the absorption liquid, but since an ammonia-based treatment liquid releases ammonia gas when added to a cement composition and is not suitable for handling, in the present invention, an alkali metal-based or alkaline earth metal-based treatment liquid is used. A processing solution is selected. Furthermore, suspended substances such as free sulfur are suspended in the treatment liquid of the Fumacs Rodax method, and the presence of these suspended substances has various disadvantageous effects on the use of the treatment liquid as an admixture, so they must be removed. do. In addition, the treatment liquid in the present invention includes those that have been subjected to some processing in addition to removal of suspended matter. Such minor treatments include removal of substances precipitated during concentration or cooling, removal of trace amounts of phenols by activated carbon treatment, salt conversion, and the like. Note that an ammonia-based treatment solution can be converted to an alkali metal base or an alkaline earth metal base by salt conversion. The composition of the solid content in the Fumax-Rhodacus process solution (based on alkali metals or alkaline earth metals and from which suspended solids such as sulfur have been removed) used in the present invention is as follows: about 75-93% (usually 85-90%) and about 2-15% (usually 5-10%) thiosulfate, totaling about 90-95%.
%, and the rest are various by-products. When added to a cement composition, the Fumax-Rhodax treatment solution used in the present invention exhibits a promoting effect of promoting strength development of the cement composition. The appropriate amount of the treatment liquid (added weight % based on cement weight) is 0.02 to 2.0% (preferably 0.05 to 1.0%). When the amount is less than this, the promoting effect is insufficient, and even when the amount is more than this, the promoting effect reaches a ceiling and becomes economically disadvantageous. The above treatment liquid used in the present invention can be used alone or in combination with other accelerators or water reducing agents. It can also be used in combination with various admixtures (AE agent, expansion agent, viscosity imparting agent, pozzolan substance powder, granulated blast furnace slag powder, etc.). However, when used in combination with the three components lignin sulfonate, oxycarboxylate and alkanolamine (particularly triethanolamine), it has been found to constitute an excellent performing standard or accelerated water reducer, and is hereby incorporated by reference. We have now provided two inventions. The amount of each additive component used in the second invention is within the above-mentioned range. (However, the total amount of lignin sulfonate and oxycarboxylate used must be 0.05% or more.) This range is the optimal one after many tests with the aim of balancing various factors such as effectiveness and economical efficiency. It was decided that In the second invention, each component may be added to the cement composition separately in a predetermined amount, and
It is also possible to add all components in one composition.
(In this case, the usage amount and component composition ratio of the admixture in the single-component composition are determined so that each component is used in the predetermined usage amount.) The lignin sulfonate in the second invention is an admixture grade obtained from sulfite pulp waste liquid. Oxycarboxylic acid salts are water-soluble compounds of oxycarboxylic acids (citric acid, arabic acid, gluconic acid, glucoheptonic acid, etc.), which are aliphatic compounds that have both hydroxy and carboxy groups in the same molecule. It's salt. Further, alkanolamine is a compound in which alkylene oxide is added to ammonia, and ethanolamines in which ethylene oxide is added (monoethanolamine, diethanolamine, triethanolamine) are preferable, and triethanolamine is particularly preferable. Both lignin sulfonates and oxycarboxylate salts are known as delayed-type water-reducing agents, and standard or accelerated-type water-reducing agents have been provided in which an accelerator such as calcium chloride is added to the lignin sulfonate and oxycarboxylate to counteract the retarding effect. There is. By blending the above-mentioned processing liquid used in the present invention with these, the retardation can be canceled out, but the amount to be blended is quite large. On the other hand, when a lignin sulfonate and an oxycarboxylic acid salt are used in combination, the performance as a water reducing agent is synergistically improved compared to when each is used alone. In addition, when the processing liquid used in the present invention is used in combination with a small amount of alkanolamine, especially triethanolamine, the promoting effect is synergistically improved rather than when used alone, so the amount of processing liquid to be blended can be significantly reduced. can. Thus, by blending the above-mentioned four components, it was possible to provide a non-chloride type standard or accelerated water reducing agent with excellent performance and requiring only a small amount of use as a whole.
Note that this water reducing agent can be used in combination with an AE agent or various admixtures if necessary. Note that a three-component water reducing agent in which a treatment liquid and an alkanolamine are blended with a lignin sulfonate or an oxycarboxylate alone can also be used. (Effects of the Invention) The present invention provides a non-chloride accelerator with excellent cost performance, and the second invention provides a non-chloride standard or accelerated water reducer with excellent performance. . In addition, efforts were made to make effective use of industrial waste treated by the Fumacs Rodax method. The industrial significance of these is extremely large. Example 1 This example shows the effect of the first invention through a concrete test. (1) Materials used for concrete tests Cement: Ordinary Portland cement Coarse aggregate: Hard sandstone crushed stone, maximum dimension 20 mm Fine aggregate: River sand from Oigawa River Fumax-Rhodax process solution (removed suspended matter): Total solid The content is 89% rhodan salt and 5% thiosulfate, with A being sodium-based and B being calcium-based. Rodan sodium: Reagent grade 1 (2) Concrete mix C = 320Kg/m ³ , W = 192Kg/m ³ , W/C = 60
%, s/a=49%, slump=18±2cm, air=1.5-2.2% (3) The test results are shown in Table 1. The curing temperature was 20℃ and 5℃. The amount of processing liquid used is based on solid content.

[Table] Example 2 This example shows the effect of the second invention through a concrete test. (1) Materials used in concrete test Cement, coarse aggregate, and fine aggregate were the same as those used in Example 1. The Fumax Rodax treatment solution is A in Example 1. The reagent sodium gluconate was used as the oxycarboxylate salt, and the reagent triethanolamine was used as the alkanolamine. Admixture grade calcium lignosulfonate was used as the ligninsulfonate. (2) For test numbers No. 7 and No. 13 in Table 2 of concrete mix C = 320Kg/m ³ , W = 192Kg/m ³ , W/C = 60
%, s/a = 39%, slump = 18 ± 2 cm, air = 1 to 2% For test numbers No. 8 to No. 12 in Table 2 C = 320 Kg/m ³ , W = 172 Kg/m ³ , W/C=
53.8%, s/a=47%, slump=18±2cm,
Air = 4±0.5% (adjusted by adding AE agent) (3) The test results are shown in Table 2. The curing temperature was 20° and 5°C. The amount of processing liquid used is based on solid content.

【table】

[Table] The second invention example is Test No. 9 to 12, which is equivalent to using a typical commercially available AE water reducer accelerated type (lignin sulfonic acid-based) at its standard usage amount of 0.25%. or more water reduction and promotion effects.

Claims (1)

[Scope of Claims] 1. An alkali metal-based or alkaline earth metal-based treatment liquid (from which suspended matter such as free sulfur has been removed) obtained by treating coal dry distillation gas by the fumax-rodax method in terms of solid content. , 0.02 to 2.0% by weight based on cement weight. 2 Based on the weight of cement (a) The alkali metal-based or alkaline earth metal-based treatment liquid (from which suspended matter such as free sulfur has been removed) obtained by treating coal dry distilled gas by the Fumax-Rodax method is converted to solid content. 0.05～
1.0% by weight (b) 0.01 to 0.25% by weight of lignin sulfonate (c) 0.01 to 0.10% by weight of oxycarboxylate and
A cement composition characterized in that the total of (b) and (c) is 0.05% by weight or more and (d) alkanolamine is contained in an amount of 0.002 to 0.02% by weight.