SU975670A1 - Raw mix for making expanded clay - Google Patents

Description

(54) RAW MIXTURES FOR THE MANUFACTURE OF KEPAJFlSHTA

The invention relates to the building materials industry, namely to the production of artificial porous aggregates for lightweight concrete, and can be used in the manufacture of expanded clay, a porous aggregate, obtained by swelling of clay granules in the firing process.

The known charge for the manufacture of lightweight ceramic products, including clay (base), 2022 wt.% Lignin and 4-6 wt.% Used clay after purification of oils obtained from petroleum products 1.

The disadvantage of this mixture is the large heterogeneity of the product obtained due to the fact that the waste clay after oil purification practically does not have the ability to evenly distribute. The mixture in the mixture is due to the hydrophobicity of the oils that envelop the clay particles. A significant amount of lignin introduced into the mixture, and, p. G1, respectively. in the semifinished product, it leads to a sharp decrease in the strength of the calcined material, since when it burns out, cavities are formed. In addition, lignin is

costly strictly funded material.

The closest technical solution to the invention is a raw mix for the manufacture of expanded clay, including, wt.%: Clay 75-88.5, bentonite powder 1024, 75 and anthracene oil for soot in the form of an aqueous emulsion paste 0.25-1.5 C2.

A disadvantage of the known raw material mixture is that the use of anthragan oil as a swelling additive in the clay mass provides in the firing process a low swelling of the semi-finished granules and results in a claydite having a relatively high o6beNBion density. Anthracene

20 oil is a product of the distillation of coal SMO.PY, a complex mixture of aromatic compounds that boil within 270-360 s. The gaseous products released during this process have little effect on the swelling of the clay mass, since the latter is not yet in its flowing state. In addition, the use of anthracene oil as a swelling agent requires, prior to introducing it into the charge, additional technological operations for the preparation of an aqueous emulsion paste. Bentonites - colloidal clays, consisting mainly of the minerals of the montmorillonite group, are an effective intumescent component of the clay mass. However, anthracene oil and bentonite clays are also pre-EU materials, using syef / MMH as dyes, withdrawn. in the oil and foundry industry as preservative wood. Therefore, the use of anthracene oil and bentonite poroics as intumescent additives is impractical, especially since the use of these additives does not have a strengthening effect. The aim of the invention is to increase the swelling of the mixture, increase the strength and reduce the cost of expanded clay. The goal is achieved by the fact that the raw mix for the production of expanded clay, including clay rock and additives, contains spongolite and selective oil purification extract as additives, with the following ratio of components, wt.%: Rock clay 80-88 Spongolit 10-15 Selective extract oil refining2-5 Spongolit - fine porosity of silicon and sedimentary origin of the rock, consisting mainly of opal tamorphous silica and impurities: hydroxides (Fe, A1., MgO, CaO) and quartz grains of glauconite. Selective oil purification extract - industrial waste, is a low viscosity fluid containing more than 50% low temperature aromatic and naphthenoaromatic carbohydrates with short side chains of unsaturated hydrocarbons and resinous substances. The advantage of the additives described is that, when mixed, finely dispersed spongolite quickly adsorbs an oil selective purification extract, which contributes to their uniform distribution in the clay mass, gives the latter good formability and improves plasticity. In the initial stage of heating the proposed raw mix in the combustion mixture organic substances that make up the extract of selective purification of oil adsorbed by finely dispersed spongolite, low-temperature gases are formed in Idea of water vapor, carbon monoxide and carbon dioxide vapor, etc. These gases accumulate and retain, in small pores of spongolite, most of which are closed during fire shrinkage of the material, are a source of pore formation and cause the redox reactions within the temperature range of EOO-1000 ° C In the process of further roasting of the semifinished product with a speed of 50-100 degrees / min the decomposition reaction j of dissociation and the interaction of the components of the mass with the release of gas-vapor products are shifted to higher temperatures. Providing resources for gazoparoobraznoy phase peaking Clay paste during its softening point in the temperature interval 1050-1200S. The CaO content in the oil selective purification extract promotes the formation of a liquid phase in the calcined material at a lower temperature and intensifies the crystallization of the amorphous silica contained in the spongolite sun-cristobalite, which reinforces the porous glass phase and thereby strengthens the expanded clay. To obtain claydite under laboratory conditions, five compositions of the raw mix based on clay from the Braginsky deposit of the Yaroslavl region with spongolite additives from the Kitaygorodskoye deposit of the Kaluga region and the extract of selective refining of oil (Yaroslavl. Chemical composition of the raw mix components are specified. mixtures are formed into semi-finished product dh 16 mm granules by plastic method, widely used in the production of expanded clay. To compare the effect of additives on the swelling of the clay mixture and higher The strength of claydite is prepared by the known raw materials and the mixture of clay without additives.Specific compositions of the components of the raw materials are listed in Table 2. The formed granules are dried in an oven after drying, the granules are burned in a mine-type laboratory furnace according to a predetermined optimum mode for After the burn, the apparent density (in the piece), the cleavage strength and the coefficient of the design quality (.table. 3). From tab. 3 it follows that the use of the proposed additives allows increasing the swelling of the raw material or reducing the apparent density and at the same time increasing the spall strength. The optimum content in the mixture is 1015 wt.% Spongolite and 2-5 wt.% Selective oil purification extract. The content of spongolite less than 10 wt.% Is not effective because it does not improve the strength characteristics of expanded clay.

The limitation of the upper limit of the spongolite content to 15 wt.% Is due to the fact that the silicon oxides constitute the most resistant, in terms of temperature, skeleton of fusible clays. Adding a significant amount of them to the clay mass significantly increases the viscosity of the pyroplastic mass and worsens the swelling conditions.

The content in the raw material of the extract of selective purification of oil less than 2 wt.% Does not ensure the formation of a significant amount of the gaseous phase during the firing of the semifinished product and, consequently, the swelling of the calcined material does not occur sufficiently intensively. The limitation of the upper limit of the content of the extract of selective purification of oil

5 wt.% Is due to the fact that a significant amount of calcium oxide, which is part of the additive, has a strong fluxing effect and, together with tbm, a liquefying effect, drastically reducing the melt viscosity in a short temperature range, which causes rapid firing of the material and complicates the burning process. The use of the proposed raw mix

allows you to significantly reduce the cost of production of expanded clay, dispose of large tonnage industrial oil refining waste, replacing the expensive products funded by them, for example, anthracene oil.

The technology of production of expanded clay on the basis of the raw mix of the proposed composition does not change in comparison with the well-known, widely used nowadays, when firing intumescent fusible clays.

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Claims (2)

1. USSR author's certificate No. 485989, cl. From 04 To 21/00, 1974. 2. USSR author's certificate No. 406813, cl. From 04 To 31/02, 1972 fnpototype U ,.