JPS6396400A - Transportation method for slurry - Google Patents

Abstract

PURPOSE:To maintain a flow state of gas-liquid 2 phase mixture within a proper range, by enlarging gradually a pipe diameter in proportion to a distance toward the downstream side, in the method of mixing gas into slurry when the slurry is transported in a pipe line. CONSTITUTION:Slurry is pressed into a transportation pipe line 3 through a directly connected line 4 from a slurry supplying apparatus 2 and at the same time, gas is supplied into the directly connected line 4 of slurry through a supply line 5 from a gas supply apparatus 1. After that, flow rates of slurry and gas are adjusted and settled at the entrance part of the transportation pipe line 3, in order to get appropriate values of a flow pattern of two phase mixture consisting of gas and slurry liquid and a virtual velocity of the gas. In this manner a volumetric flow rate of the gas increases due to a pressure drop at the down stream of the transportation pipe line 3, however, as a diameter of a transportation pipe line increases in proportion to a distance toward the downstream side, any change in a virtual velocity of the gas can be reduced.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for transporting slurry.

[Conventional technology]

Conventionally, when transporting a slurry with a very high viscosity through a pipeline, it has been known that if gas is injected for transport, the pressure loss is smaller than in the case of a single-phase slurry flow.

The effect of reducing pressure loss by injecting gas in this way is affected by the flow pattern in the pipeline and the apparent flow velocity of the gas, and a large pressure loss will occur only when the flow pattern and apparent flow velocity are within a certain range. It has a reducing effect.

In other words, when transporting slurry through a pipeline, even if the flow conditions of the flow state and apparent flow velocity are set appropriately at the pipeline inlet and the slurry is sent, the flow state is not appropriate because the volume flow rate of gas increases due to the pressure drop downstream of the pipeline. If the flow conditions deviate from the range, the effect of reducing pressure loss may not be obtained, and the overall effect of reducing pressure loss due to gas injection may be small or may be completely absent. For this reason, a conventional method has been used.

(1) Only apply to short pipelines where pressure loss affects transportation.

(2) A certain amount of gas is discharged from the middle of the piping, and the slurry is transported while maintaining the flow state within a certain range.

[Problem that the invention seeks to solve]

The conventional method described above has the following problems.

(1) Short pipeline transportation up to the pressure drop limit is not suitable for practical use because the transportation distance is limited; (2) The equipment and mechanisms for discharging a certain amount of gas from the middle of the pipe are complex and expensive, resulting in transportation costs. becomes a dog.

[Means for solving problems]

The present invention has been made to solve these problems, and is a method of transporting slurry by injecting gas into the slurry via a pipeline. Provide transportation methods.

[For production]

By gradually increasing the diameter of the pipe toward the downstream,
By keeping the flow state of the gas-liquid two-phase mixture within an appropriate range, it is possible to transport the gas-liquid two-phase mixture with less pressure loss than in the case of a single-phase slurry.

〔Example〕

FIG. 1 is a schematic diagram showing the configuration of the present invention. In the figure, 1 is a gas supply device that can continuously supply gas at a constant flow rate, 2 is a slurry supply device that can continuously supply a constant flow rate of slurry, and 6 is a transport pipe whose diameter increases as it goes downstream. It is directly connected to the supply device 2. Further, a supply line 5 from the gas supply device 1 is connected to a direct connection line 4 between the slurry supply device 2 and the transport pipe 6.

Next, this effect will be explained.

Slurry is pressurized into the transport pipe 3 from the slurry supply device 2 through the direct connection line 4, and at the same time, gas is supplied from the gas supply device 1 through the supply line 5 to the direct connection line 4 for the slurry. Furthermore, after that, the flow rate of the slurry and the flow rate of the gas are adjusted and set so that the flow pattern of the two-phase flow of the gas and the slurry liquid and the apparent flow velocity of the gas at the inlet of the transport pipe 3 are set to appropriate values. In this way, the volumetric flow rate of the gas increases due to the pressure drop downstream of the transport pipe 3, but since the pipe diameter of the transport pipe 6 becomes narrower as it goes downstream, changes in the apparent flow velocity of the gas are prevented. The slurry can be flowed while maintaining an appropriate flow pattern.

At this time, since the flow state only needs to be within a certain range, the change in the pipe diameter of the transport pipe B does not need to be changed continuously as shown in Fig. 2 (al), but as shown in Fig. 2 (bl and ( cl
A similar effect can be obtained by combining and connecting pipes with different diameters as shown in the figure, gradually increasing the diameter.

Furthermore, if the pipe diameter is changed in multiple stages, it is also possible to perform minute flow velocity control.

Furthermore, the present invention can be applied to the transportation of high viscosity oils having rheological properties from high viscosity slurries.

〔Effect of the invention〕

The present invention provides the following effects.

(1) Since the flow state in the slurry transport pipeline can be maintained within a certain range, there is no need to install equipment to discharge gas from the middle of the pipeline, making the equipment inexpensive and easy to operate. be.

(2) By changing the diameter of the transport pipe in multiple stages, precise transport control is possible, and at the same time it can be applied to long-distance pipelines.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing the configuration of one embodiment of the present invention, and Figs. 2 (al to c) are perspective views showing other embodiments of changing the pipe diameter of the feed pipe. 1: Gas supply device , 2 Nis slurry supply device, 3: transport pipe, 4: direct connection line, 5: supply line.

Claims (1)

[Claims] A method for transporting slurry by injecting gas into the slurry by pipeline, characterized by increasing the diameter of the pipe toward the downstream.