RU2154602C1 - Sulfur cement production process - Google Patents

Abstract

FIELD: manufacture of building materials. SUBSTANCE: invention relates to production of composites based on sulfur cement for manufacturing building materials. Homogeneous solution of sulfur (90-98%) and modifier (2-10%) is treated for 5 to 20 s by rotating electromagnetic field in velocity layer apparatus at 140-150 C. Modifier is petroleum residue, for example mazut used with no preliminary treatment or preliminarily irradiated for 10 to 60 s by rotating electromagnetic field at 300-350 C. EFFECT: intensified process and simplified technology. 3 cl, 3 ex

Description

 The invention relates to the production of sulfur-based composite materials for the manufacture of building materials and can be used in industrial civil and road construction.

A known method of producing sulfur cement (copolymer or modified sulfur) ("Seropolymer concrete. Production Guide. USA Institute of sulfur. 1994) by chemical interaction of sulfur with dicyclopentadiene (DCPD), leading to the formation of copolymer sulfur, consisting of long chains of polysulfides . The reaction of sulfur polymerization with DCPD occurs with the mixing of sulfur and a modifier in the temperature range 130-149.5 ^o C for 30-40 minutes Such gray cement, when mixed with inert constituents, does not form sulfur concrete, in which there is modified sulfur. Upon hardening, strong sulfur concrete is formed that does not respond to changes in temperature and other environmental influences.

The disadvantages of this method are the duration of the process and the high toxicity of DCPD. The maximum permissible concentration of DCPD is 1 mg / m ³ and, in addition, DCPD is explosive and fire hazard.

The closest analogue to the described method (prototype) is a method for producing copolymer sulfur (UK patent N 1576515, IPC C 01 B 17/00), where an olefin hydrocarbon polymer material obtained from oil is used as a modifier. The method consists in mixing sulfur with a chemical modifier at a temperature of 130-149.5 ^o C for 15-40 minutes Violation of the dosage of a chemical substance or heating of the reactor and the mixture above 150 ^o C leads to an exothermic reaction. In this case, there is a strong release of hydrogen sulfide, foaming of the mixture and deterioration of the product. The above is especially relevant in the case where it is proposed to prepare a concentrate in which a chemical substance pre-reacts with less sulfur than is necessary in the finished mixture. To increase the fire resistance of sulfur cement, additives are added, for example, 1,5,9 cyclododecatriene or the reaction product of diphenoxyphosphinic acid with sulfur and methyl styrene.

The disadvantages of this method are the difficulty of dispensing chemicals, as well as the need to observe the temperature regime, since an overdose of additives or overheating of the reactor above 150 ^o C leads to an exothermic reaction, which in turn leads to increased formation and evolution of hydrogen sulfide, foaming of the mixture and deterioration of product quality.

 The aim of the present invention is to intensify the process of producing sulfur cement and simplify the technology of its production.

This goal is achieved by the fact that the production of sulfur cement is carried out by processing a homogeneous solution of sulfur and a modifier by rotating the electromagnetic field of the apparatus of the vortex layer B 150K-01 at a temperature of 140-150 ^o C for 5-20 s. The ratio of the components of the solution is the following, wt.%:
Sulfur - 90-98
Modifier - 2 - 10
The chemical interaction of sulfur with a modifier in the vortex layer apparatus occurs without a noticeable increase in the thermal effect, which greatly simplifies the technology of production of sulfur cement and does not lead to the emission of harmful substances, such as hydrogen sulfide.

As a modifier, oil residues of atmospheric distillation of paraffinic oils, as well as the remainder of their vacuum distillation with a density close to 1000 kg / m ³ and an iodine number of 0.7 mg per 100 g of KOH, for example fuel oil, can be used.

To increase the iodine number (i.e., to increase the olefin hydrocarbon content) of the modifier, before mixing with sulfur, the oil residue is pre-treated at a temperature of 300-350 ^o C for 10-60 with a rotating electromagnetic field in a vortex layer apparatus B150K-01. In this case, the iodine number of treated fuel oil is increased by 2.5-5 times compared with the initial one.

 The use of the oil residue as a modifier is due to its chemical interaction with sulfur, which is expressed in its addition to the ends of polymer sulfur, saturation of its bonds, termination of the polymerization process and its stabilization in this state. Such conditions are created in the apparatus of the vortex layer of the V150K-01 series, in the working zone of which a powerful rotating electromagnetic field is created, which picks up small ferromagnetic rods (needles) placed in it, causing them to rotate. As a result of the interaction of the field with the needles, a number of effects are generated (magnetostriction, cavitation, electrolysis, microarc formation, etc.), which, together with the impacts of the needles, intensify the reaction of sulfur with the modifier, breaking monomolecular bonds and stimulating the formation of sulfur cement.

 The quality of the sulfur cement obtained was evaluated by the method of producing polymer sulfur of the Kazan University of Chemical Technology, where the amount of polymer sulfur was determined by the difference in the total sulfur content determined by burning a sample in an oxygen stream and extracted sulfur determined by extraction of the initial sample with hexane, which determined the properties of sulfur cement.

 Example 1

Use gas sulfur Astrakhan gas condensate field having the following characteristic:
Sulfur content, wt.% - 99.98
The amount of ash,% - 0.02
Density, kg / m ³ - 1860
The content of hydrogen sulfide, wt.% - 0,001
A modifier is used, fuel oil is the remainder of atmospheric distillation of the stable condensate of the Astrakhan gas condensate field, previously passed through the vortex layer apparatus at a temperature of 300-350 ^o C for 10-60 s. The modifier has the following characteristics:
Density, kg / m ³ - 899 - 960
Viscosity at 60 ^o C comp - 33.2 - 40.5
Iodine number, mg per 100 g of KOH - 1.86 - 3.50
Gas sulfur in an amount of 1800 g is heated to a temperature of 140-150 ^o C, a modifier is introduced in an amount of 2% by weight of sulfur, also heated to 120-150 ^o C, stirred for 1-2 minutes until a homogeneous solution is formed and placed in a capsule of the apparatus vortex layer for 5 s. The resulting sulfur cement is poured into molds and after cooling for 24 hours, it is analyzed for polymer sulfur content.

 The polymer sulfur content is 15%.

 Example 2

 The experimental conditions are similar to example 1. The input modifier is 5% by weight of sulfur. The duration of sulfur in the apparatus is 10 s.

 The polymer sulfur content is 72%.

 Example 3

 The experimental conditions are similar to example 1. The introduced modifier is 10% by weight of sulfur. The residence time of the mixture in the apparatus is 20 s.

 The polymer sulfur content is 21%.

Thus, the introduction of a modifier in an amount of 2-10 wt.% And processing the mixture in the apparatus under the influence of an alternating electromagnetic field for 5-20 s provide sulfur cement with a polymer sulfur content of 15-72%, which is sufficient to produce high-quality sulfur concrete . The resulting sulfur cement has the following characteristics:
The content of polymer sulfur, wt.% - 15-72
Density, kg / m ³ - 1789
The content of hydrogen sulfide, wt.% - No
and can be used as a binder in the manufacture of sulfur concrete products without additional processing.

 Thus, the proposed method for producing sulfur cement in the apparatus of the vortex layer allows to reduce the reaction time in comparison with the prototype by more than 100 times, which leads to significant energy savings. The use of a heavy residue as a sulfur modifier, which is a complex mixture of high molecular weight compounds, allows to obtain high-quality sulfur cement without special expensive and scarce additives, which also leads to a significant reduction in the cost of sulfur cement and simplification of its production technology.

Claims (2)

1. A method of producing sulfur cement by the interaction of sulfur and an oil-based modifier at a temperature of 140 - 150 ^o C, characterized in that a homogeneous solution of sulfur and a modifier for 5 to 2 s is affected by a rotating electromagnetic field in the vortex layer apparatus in the following ratio, wt.%:
Sulfur - 90 - 98
Modifier - 2 - 10
2. The method according to claim 1, characterized in that as a modifier use a modified oil residue, such as fuel oil, pre-treated with a rotating electromagnetic field. 3. The method according to claim 2, characterized in that the treatment of the oil residue by a rotating electromagnetic field is carried out for 10 to 60 s at a temperature of 300 - 350 ^o C.