Method for processing of liquid hydrocarbon raw materials

Abstract

The invention pertains to a method for processing of liquid hydrocarbon raw materials. The method includes preliminary pretreatment of a flow of raw materials and further processing with fractionation. The pretreatment is performed by forming a primary flow of liquid hydrocarbon with the characteristics of a straight tubular laminar flow and then directing that flow through a spiral tubing at a velocity the maximal value of which maintains laminarity of the laminar primary flow through the spiral tubing. The laminary primary flow is fractionated following the pretreatment. The invention has applications to the field of petroleum processing and may find application in the petroleum and petrochemical industries, and in the field of fuel power engineering.

Claims

1. A method for processing liquid hydrocarbon raw materials, said method comprising: pretreating liquid hydrocarbon materials by forming a laminar primary flow of the liquid hydrocarbon material with characteristics of a straight tubular laminar flow, and then directing the laminar primary flow through spiral tubing at a velocity, the maximal value of which maintains laminarity of the laminar primary flow through the spiral tubing; and fractionating said laminar primary flow following said pretreating.

2. The method according to claim 1, in which the mentioned velocity is provided by regulated dynamic pressure of raw material primary flow.

3. The method according to claim 1, in which more than one primary flow is formed.

4. Method according to claim 2, in which the volume created by the dynamic pressure is preserved in its natural fluctuation limits.

Description

BEST MODE FOR CARRYING OUT THE INVENTION

(1) Example of practical performance of the method announced is illustrated by FIG. 1, where operational diagram of apparatus for liquid hydrocarbon raw materials processing is presented, and effectiveness of the method announced is illustrated by FIG. 2, where data on crude oil and oil processed one time with use of the method announced are presented.

(2) This apparatus consists of reservoir for hydrocarbon raw materials pretreatment 1, pump 2 for creation of raw material dynamic pressure in the chamber, pump 3 for heat-carrying agent supply, evaporator 4 for separation of light oil fractions, mixer 5, and fractionation reactor 6. Moreover the apparatus has different equipment for raw material storage and collection of the products produced (not shown).

(3) Reservoir for pretreatment 1 has a system of hydrodynamically separated channels (tubular units, pipe-lines) in which any flow regime can be maintained. Each tubular unit has straightforward initial part, as far as possible smoothly conjunct with raw material storage wall. It was made with purposes of maximal decrease in hydraulic resistance occurring due to difference in tube and storage sizes and prevention of eddy (turbulence) in this zone.

(4) The straightforward part of pipe-line smoothly transforms into spiral-shaped. This part shape can be determined, in particular, by a three-dimensional curve which projection on the plane orthogonal of vertical axe, is, for example, Archimedean spiral, logarithmic or hyperbolic spirals. Regulated computational form of vortex flow guarantees achievement of significant flow rotation velocity in axile zone wherein formula (2) is true.

(5) Pipe smooth curve is considered the most suitable from the point of view of pressure losses due to absence of dangerous zones of turbulence. However maximal radius of the pipe curve is to be selected on the basis of the condition of achievement of flow velocity critical value on the axile zone boundary, wherein hydrodynamic stability of entering this part flow against possible vortex laminarity violations can be achieved. At that circumferential velocity values regular distribution depending on distance from rotative axis shall be taken into consideration.

(6) Complex of the conditions developed for the process stability supporting being performed for one separate channel (or pipe-line) automatically performs for the whole channel system (or pipe-lines).

(7) Other elements of the apparatus are no different from the known on the technical level.

(8) This method is performed in the following manner.

(9) Hydrocarbon raw materials (oil) are fed into the tank for pretreatment 1 from the storage through pump 2. Pump 2 produces hydrodynamic pressure for providing of flow velocity interval needed for primary flow laminarity supporting. At determining of the velocity interval mentioned above according to formula (1) raw feedstock viscosity and pipe-line geometric configuration parameters are to be taken into consideration. Further the primary flow curls along spiral trajectory with preservation of computational laminarity, which is maintained by regular hydrodynamic pressure of raw materials in intake branch pipe, allowing on the one side to use rotative motion source power in full for vortex flow producing, on the other side, to maintain permanent flow characteristics up to axile vortex zone boundary (as a rule it forms up to half of vortex flow radius). Velocity distribution in the vortex has axisymmetric characteristics with velocity increase up to the maximum value and pressure decreasing down to the minimum in the vortex axile zone, at that from the moment of the vortex formation the law of conservation of momentum starts operating. Features of the vortex, as a dynamic self-organizing structure are such that velocities in the axile zone reaches critical values and there are conditions for necessary phase transition of working fluid microvolume with release of significant energy, contributing intensification of further separation process of hydrocarbons into fractions. In the evaporator 4, where hydrocarbons flow enters from the draining zone of reservoir 1, a partial separation of light hydrocarbons in the form of a gas-vapor mixture from dehydrated heavy component takes place. Further, heavy hydrocarbons, mixed in a mixer 5 with coolant supplied by pump 3, enter the reactor 6 for further refining.

(10) FIG. 2 presents comparative results for separation of light and heavy crude oil residue and oil, refined by the announced method, in percentage of light hydrocarbon fractions to the whole mass. High viscosity materials with high content of resins and asphaltenes were processed.

(11) Refined oil quality evaluation made according to integrated indicator of pipeline oil quality (K), calculated on the basis of the above data by the method described in the study of Degtiarev V. N. Oil Quality Bank, Oil Industry, 1997, No. 3, p. 62-63 [3], shows oil quality increase in several times. Integrated indicator of refined oil quality was N.sub.ref=0.455 for initial oil indicator of K.sub.in=2.92. Downward bias of unit deviation of the Quality integrated indicator leads to falling costs of processing.

INDUSTRIAL APPLICABILITY

(12) The announced method can be used to process both light and heavy crude oil and petroleum products, and allows by means of pretreatment of hydrocarbon flow to improve substantially the quality of the finished product, as well as intensity and energy efficiency of the rectification process.