CC BY
6
Gurbanova Zumrud Ramazan, Ph. D, associate-professor of the department "Chemistry and Chemical technology of inorganic substances" Azerbaijan State Oil and Industry University, E- mail: kerem-shixaliyev@mail.ru
THE USE OF WASTE PRODUCTS OF SODA PRODUCTION TO MAKE NON-SHRINKAGE OIL-WELL CEMENT
Abstract: the use of OJSC "Soda" waste as a carbonate component for the production of sulfated clinkers was investigated. The optimum conditions for hydrating and qualitative cement obtaining have been studied. Physico-chemical and physico-mechanical properties of synthesized clinkers were determined: setting time was from 8h 15 min to 9 h 30 min, when the ultimate strength of cement was within 2 days; linear expansion of cement was within the limits of the norm; and concentration of the solution was 1940 kg.m 3. On the basis of synthesized clinkers, it was found that the results of cement compositions refer to non-shrinkage cement compositions for oil wells.
Keyword: waste products of soda, oil-well cement, hydration, sulfated clinker.
In most cases destruction of the cement ring on the back surface chosen [1-3]. As a resul ofX-ray phase and petrographic analyses it depends on the tension generated during compression. Thus, the has been determined that limestone consists of mainly calcite (more problem of non-shrinking material production remains urgent. As than 50%) and clay component consists of montmorillonite and an object of researches the raw materials used in experimental ce- hydromica. Chemical composition of chosen materials is given in ment plant of Podolsk - clay, gypsum and also man made materials tablel. For investigation mineral formation process a mixture was of "Soda"OJSC-carbonized and non-carbonized sludge have been prepared.
Table 1. - Chemical composition of raw materials
Material The composition of oxides, mass%
SiO2 Al2O3 Fe2O3 CaO MgO SO3
Limestone 6.56 1.58 0.86 50.02 1.18 -
Clay 51.93 15.17 6.86 7.29 1.75 2.92
Gypsum 4.59 1.18 0.55 34.08 3.13 38.20
Sludge: Carbonized 4.10 0.35 0.15 63.50 3.50 4.10
Non-carbonized 1.80 0.30 0.10 46.20 4.00 4.20
This mixture was used for the investigation oflow base, high base sulphofritic clinker and intermediate base clinker. According to their compositions they are similar. According to X-ray phase analysis the material contains calcium sulfate, calcium and aluminum oxychloride and a little magnesium hydro oxychloride. The composition of raw-material mixture was calculated for obtaining sulphofritic clinkers to determine carbonized or non-carbonized sludge [2-3]. The obtained results show that man - made materials of OJSC "Soda" can be used as a carbonate component. Presence of sulfate calsium in their content considerably decreases gypsum amount used for mixture preparation. Using carbonized sludge, a mixture can be made on the base of 4,5% traditional components [4-5].
Experimental part
As a sample clinkers made from the raw material of Podolsk cement plant have been taken. This raw-material is made by wet grinding method in laboratory porcelain mill within 6 hours. Then the sludge is dried in the drying apparatus at temperature 60 (5 (C with 1-2% moisture content. The content of raw materials is given in table 2. During hydraulic process cylinders with 5 sm 2 diameter and 3 sm 2 height were made to produce raw-material mixture with kg (sm 2 pressure)).
High temperature furnaces with chromite lanthanum heaters of 1100, 1150, 1180 and 12000C and 5, 10, 15, 20, 30, 60 isothermal stability are used to burn the samples. The experiment shows that complete mixing of Ca0 with the raw-material depends on the composition of the clinker. 0,98-1,0 bond degree of low base clinker reaches up to 1180 °C temperature. Isothermal is (T = 1180 °C) and amount of Ca0 in the mixture is 0,73-0,78 mass fraction and while increasing its stability, it reaches up to 0,98-1,0 within 5 minutes. High-base clinker is required for mixing calcium oxide with raw-materiales and it needs to be heated at 1250 °C temperature. Mixing of limestone is carried out within 30 minutes. Ca0 bond degree of intermediate composition of clinkers is 0,98-1,0 and it reaches up to 1200 °C ((= 30 min. ). Bond degree of calcium oxide is shown in table 2.
Bond kinetics in the mixtures on the base of solid residues with CaO soda content and its presence in simple content controlling mixture show that synthesis process of sulphofritic clinkers occurs more quickly than controlling mixture in the obtained composition. Probably mineral formation frequency of the reaction is related to the role of mineralization while burning the clinkers and being of chlorine compounds in sludge [6; 7].
Table 2. - Bond rate of calcium oxide with raw -material mixture
Mixture Minute -at temperature, °C
1100 1180 1250
Sulphofritic clinker:
low base sulphofritic clinker (LBSC) 5 0.78 0.97 -
10 0.83 0.98 -
20 0.89 0.99 -
30 0.92 0.99 -
High-based - HBSC 60 0.95 1.0 -
5 0.75 0.87 0.99
10 0.79 0.90 0.99
20 0.83 0.96 1.0
30 0.88 0.99 1.0
Intermediate-based 60 0.88 1.0 1.0
5 0.73 0.85 0.98
10 0.79 0.92 0.99
20 0.81 0.98 0.99
30 0.85 0.99 1.0
Controlling clinker 60 0.85 1.0 1.0
5 0.72 0.85 0.97
10 0.78 0.88 0.99
20 0.83 0.92 0.99
30 0.86 0.96 1.0
60 0.88 0.97 1.0
During the formation of sulfated clinkers, the constant of CaO bond reaction rate was calculated due to the results. The analysis of the obtained data shows that the rate of bonding process is limited by diffusion process and described by Yander equation. Phase composition of the synthesized clinkers was defined by X-ray phase and petrographic analyses. It was determined that while burning of
The results obtained during the investigation of hydration process of the clinkers synthesized in micro-preparations by petrographic method, testify great hydration activity of the product takes places namely on the base of man-made materials [7-8]. Durability of iron ettringite formed in the sample within first hours of hydration continues up to 14 days. And it enables to get an intensive, durable effect maintaining the system and liminating displace-
low-base sulphofritic mixtures consisting of man made materials at temperature (Tb (1180-1200 (C) the phase composition of the obtained clinkers differs from calculated one. It depends on the formation of alloys and high-base liquid phase. Phase composition in the clinkers having high-base mixture and intermediate composition is nearer to the calculated one (table 3).
ment deformations. The obtained cements were tested due to the requirements. The results of physico-mechanical experiments are shown in table 4. Thus, by increasing the quantity of sulphofritic clinkers added into the cement content from 5 to 15% mass, linear expanding of samples increases from 0,03 to24%. Practically durability of cement in small doses of sulphofritic clinkers doesn't change.
Experiment Composition of component,%
PCC LSFC HSFC ISFC gypsum
1 2 3 4 5 6
1 90 5 - - 5
2 83 10 - - 7
3 75 15 - - 10
4 90 - 5 - 5
Table 3. - Phase composition of sulphofritic clinker
Experiment Clinker Phase composition,%
C2S C3S 3CF (CS) c2f (CS)
1 LSFC 32 10 32 18
2 HSFS 16 32 7 40
3 ISFK 24 25 17 28
Table 4. - Content of the cement
1 2 3 4 5 6
5. 83 - 10 - 7
6. 75 - 15 - 10
7. 90 - - 5 5
8. 83 - - 10 7
9. 75 - - 15 10
But at 15% mass increase of the quantity of sulphofritic clinkers durability of the cement decreases. Formation of a great amount of three-sulfate hydro- sulphofritic calcium occurs. Solidification in hydration process reaches to such extent that destruction process decreases the duriability. Electron-microscopic investigation of cement shows that, during hydration process of
sulphofritic phase mainly iron ettringite, mono hydro-sulphofrit-ics and calcium hydroferrite, iron hydroxide gel are formed. In joint hydration of the minerals of sulphofritic clinkers and portland cement the phases cause occurence of expanding solidificat-ing of cement system.
The results have been shown in table 5.
Table 5. - Durability of cement
Code of cement Increase of durability, MPa/day Expanding,%
bending compression (pressing)
2 28 2 28 2 28
1. 2.3 4.9 5.8 11.3 0.03 0.08
2. 2.2 4.5 5.2 10.7 0.05 0.10
3. 1.7 3.4 4.0 8.7 0.11 0.18
4. 2.7 5.6 6.6 13.4 0.07 0.12
5. 2.4 5.3 6.2 13.0 0.10 0.15
6. 1.8 3.2 4.1 8.8 0.14 0.24
7. 2.5 5.1 6.0 12.1 0.05 0.09
8. 2.3 5.0 6.1 11.6 0.08 0.11
9. 2.2 4.7 5.2 10.4 0.10 0.18
The results of estimation of cement hydration rate allow to place sulphofritic cements in the folloving order: low base, intermediate base and high base. Namely it enables considerably to decrease the amount of sulphofritic addition of the system in equal values of linear expanding of the system.
Sulphofritic clinkers are obtained by burning the raw-materials containing limestone, gypsum of Podolsk cement plant and carbonized sludge of OJSC "Soda" at 1180 °C temperature. The analysis of the clinker obtained by physico- mechanical method shows that, this composition is nearer to high-base sulphofritic clinker. The composition of carbonized double-calcium ferrite is 38% mass. Oil-well cement was produced by grinding in a batch mill consisting of 80% mass of Portland cement clinker, 10% mass of sulfoferritic clinker and 10% mass of gypsum. The fineness of the cement grinding was 13% residue on sieve N 008 on 3300 sm 2g 1 specific surface areas.
According to GOST 1581-78, physico-mechanical properties of the obtained cement are as follows: 0,44 for 195mm; setting time: beginning - 8h 15 min.; end- 9 h 30 min: concentration of the solution - 1940 kg.m 3; the ultimate strength of cement within 2 days was
3.0 MPa, at a bend of at a compression - 11.2 MPa; linear expansion of cement was 0.06%.
So, the tested cement refers to the non-shrinkage formations of oil-well cement.
Conclusion
1. Chemical and mineralogical composition of man-made materials (carbonized and non-carbonized sludge) OJSC "Soda" can be used as a raw material component in the production of sulphofritic clinkers.
2. Physico-chemical analysis established the optimal compositions of sulphofritic clinker used as an expanding additive in the production of non-shrinkable cements. By the degree of hydration and the physical and mechanical properties of cements, the clinker containing high base sulfated minerals is most effective.
3. Physical and mechanical properties of sulphofritic-containing cements showed the possibility of creating a non-shrinkage cement of high quality. The optimal composition of cement should contain no more than 10% mass of sulphofritic clinker.
4. Experimental-industrial tests carried out on the SRI of experimental cement plant confirmed the results of laboratory studies.
References:
1. Karimov N. K., Gubkin N. O. Peculiarities ofWell Cementing in Salts. - M.: Nedra, - 1974. - P. 114.
2. Agzamov F. A., Karimov N. K., Akchurin K. S. Preparation of expanding oil-well cements//3/veKTpoHHbrn научный журнал «Нефтегазовое дело». - 2001. - No. 2. URL: http://ogbus.ru/eng/authors/Agzamov/preparation.pdf
3. Kuznetsova T. V., Shatov A. A., Dryamina M. A., Badertdinov R. N. Use ofWastes from Soda Production to Produce Nonshrinking Oil-Well Cement // Russian Journal of Applied Chemistry, May - 2005. - Volume 78. Issue 5, - P. 698-701.
4. Ponin V. I., Babkov V. V., Merkulov Y. M. and others. On the construction sites of Russia. - 1984.
5. Shatov A. A., Dryamina M. A., Badertdinov R. N. Potential Utilizations of Soda Production Wastes // Chemistry for 8. Rybiev I. A., Asfaltovye betony, VSustainable Development, - No. 12. - 2004. - P. 565-571.
6. RF Application - No. 2002120166, 24.07.02.
7. Krasheninnikov S. A., Tekhnologiya kaltsinirovannoy sody i ochishchennogo bikarbonata natriya, Vysshaya shkola, - Moscow, - 1985. -P. 287. ysshaya shkola, - Moscow, - 1969. - P. 264.
