Valentina Kroz

Introduction

               Ceramics are materials and products with the behaviors similar to stone properties received in the course of technological processing of mineral raw materials (as a rule, clay) and its sintering at heats.
           The term "ceramics" occurs from the Greek words keramike – potter's art and keramos – clay. Therefore, under technology of ceramics always had in view of manufacture of materials and products with the set properties from clay raw materials. Presently as technology of ceramics understand a science about methods of manufacture of products from different mineral raw materials by their formation, drying and roasting.

Objectives and goals

               The purpose of the given work is research of possibility of application stripping breeds as raw materials for manufacture of ceramic building materials. The main task – reception of a ceramic brick and a tile with use stripping breeds.

           Objects of research are stripping clay breeds of the Rusinovsky deposit and a deposit the White beam. It is a lot of this waste, but they do not find practical application though on the chemical-mineralogical structure these materials are close to the clay applied in building. The purpose of an experimental part of work is research of possibility of use of the given kind of clay materials as the basic raw materials for manufacture of products of building appointment. We will result a chemical compound of investigated clay materials (kaolin (KO), loam (СК) and clay of the Rusinovsky deposit (Р - 3)) in % (weights.):

                Table 1 – the Chemical compound of investigated materials.
               

               Investigated materials on mineralogical structure mainly are presented by a clay mineral kaolin (25 – 39%), and as others clay there is a hydromica, montmorillonite, microwedge, plagioclase, mica fragmental, and the basic impurity – quartz (27 – 36%). On chemical-mineralogical structure it is visible that the given materials possess approximately the same structures, as raw materials used in the industry that allows to assume possibility of application of the given kind of materials in technology of building ceramics, for example, for manufacture of a building brick and a tile. The investigated raw materials have been checked up by practical consideration in vitro on the basic properties. Results of experiences are resulted in table 2:

                Table 2 – Properties of investigated raw materials:
               

            

Picture 1 - technological process (animation gif - animator,15 kadrs, relay 100 ms, 68,7 kb)

               Water for formation shows, what quantity of water is necessary for adding to absolutely dry clay (in % of weights.) For reception of paste of a normal working consistence:

                                                                                          

                мв – weight damp навески clay of a normal consistence,g;
                мс – weight absolutely dry clay,g.

               On plasticity number (clay classify on 5 groups: high-plastic (П > 25), middle plastic (П = 15 - 25), moderately plastic (П = 7 - 15), low-plastic (П = 3 - 7) and nonplastic (do not form plastic paste).

           According to the received data resulted in table 2, it is possible to assert that the investigated raw materials are quite suitable for manufacturing of products on plastic technology. From investigated stripping clay breeds laboratory samples for what initial materials crushed made, sifted through a sieve 05, prepared ceramic weight with optimum working humidity. Formation of samples made in the plastic way. Clay sifted through a sieve 05, shut water before reception of the test of a normal consistence, Defined air and fire setting, a roasting interval (within 950 – 1100 ^oС). Roasting of samples made in the electric furnace. Results of experiences at optimum temperature of roasting are resulted in table 3:

                Table 3 – Results of research of laboratory samples
               

               Air setting (Ув) – essential reduction of volume of a raw, an event at removal of a moisture as a result of drying. Fire setting (Уог) – change of the sizes of a product, an event at roasting. Air and fire setting on laboratory samples defined by measurement of the sizes of samples before drying, after drying and after roasting. The shrinkable phenomen in clay materials deepen on their structure and properties.

           Drying conditions also can influence on size setting. So, at slow drying under natural conditions change of the sizes of samples will be more than at artificial drying with rather fast lifting of temperature. In an interval where there are shrinkable phenomena, the length of the sample linearly depends on its humidity. Hence, the size of shrinkage for the same clay will be defined by initial humidity of the sample. Therefore it is necessary, that initial humidity of samples was identical and corresponded to the normal forming. Linear air relative setting Uv quantitatively express change of the sizes of the ceramic sample in percentage of its initial length.

                                                                                          

               Where l₀ и l₁ – length mold the sample and the sample after drying accordingly, mm.

                                                                                          

                Where l₀ и l₁ – length mold the sample and the sample after drying accordingly, l₂-length of the sample after roasting, mm.

               Mechanical properties are characterised by ability of a material to preserve to all kinds of external influences with application of force. On set of signs distinguish durability of a material at compression, a bend, blow, torsion etc., hardness, plasticity, elasticity, abradability. durability on pressure (Gсж) — property of a material to resist to destruction under the influence of the pressure arising from loading. Strength at a bend pays off under the formula:

                                                                                          

                Where G_сж - mechanical durability, kgs/sm²;
                Р - loading, kg;
                S - the area, sm²

               

               After roasting samples were exposed to careful survey. Samples from clay of the Rusinovsky deposit, before roasting had a grayish shade, and after have got more white colouring. Samples from kaolin before roasting had red colour, and in the range of temperatures 1000 – 1050 ^oС change of colour from pinkish to the yellow was observed. Samples from loam before roasting had brown colour, and at temperatures 1000 – 1050 ^oС – change of colour from red to dark-red was observed. And it is noticed that colouring influences both a chemical compound of investigated clay materials, and the roasting environment.

               According to the received data it is possible to draw following conclusions::

- investigated stripping materials possess approximately the same properties, as raw materials used in a ceramic industry;
- durability of investigated raw materials corresponds to durability of the ordinary building brick used for construction of 2 and 3 floor buildings;
- the raw materials also are suitable for reception of products of dense ceramics, for example, tiles and clinker a brick.

               Having analyser the received results it is possible to make a conclusion that stripping breeds are quite suitable for reception of various ceramic materials.Therefore it is necessary to move in this direction and to study possibilities of their application in wider interval.

               List of literature

1. Химическая технология керамики и огнеупоров /Под ред. П.П. Будникова. - М.: Стройиздат, 1972. - 552 с.
2. Бетехин А.Г. Курс минерологии. – М.: Стойиздат, 1956. – 382 с.
3. Чаус К.В., Чистов Ю.Д., Лабзина Ю.В. Технология производства строительных материалов, изделий и конструкций. – М.: Стройиздат, 1988. – 448 с.
4. Августиник А. И. Керамика. - М.: Промстройиздат, 1957. - 483 с.
5. Канаев В.К. Новая технология строительной керамики. – М.: Стройиздат, 1990. – 264 с.
6. Крупа А.А., Городов В.С. Химическая технология керамических материалов. – К: В.Ш., 1990. – 399 с.
7. Справочник по производству строительной керамики./Под ред. Д.Н. Полубояринова, В.Л. Балкевича - М.: Стройиздат, 1961.- 640 с.
8. Кроз В.В., Дударева Е.А., Беломеря Н.И. Керамическе материалы строительного назначения на основе вторичных сырьевых материалов. - Материалы VIII международной конференции «Охрана окружающей среды и рациональное использование природных ресурсов». - Донецк: ДонНТУ, 2009 г. - 234 с.
9. Юшкевич М.О., Роговой М.И. Технология керамики. - М.: Стройиздат, 1969. - 349 с.
10. Кошляк Л.Л. Калиновский В.В. Производство изделий строительной керамики. - М.: Высшая школа, 1985. - 189 с.
11. Кирпич строительный. Краткий справочник
    http://kirpi4ik.ru/