CN205100175U - A structure for providing ecological flow in downstream reaches of hydropower projects - Google Patents

Abstract

The utility model discloses a structure that provides ecological flow of hydraulic and hydroelectric engineering low reaches river reach, including the engineering dam, the engineering dam divide into upper reaches river reach and low reaches river reach with the river, is provided with upper reaches cofferdam and low reaches cofferdam respectively in engineering dam upper reaches and low reaches, is equipped with the diversion tunnel between upper reaches river reach and the low reaches river reach, and the diversion entry of diversion tunnel arranges the upper reaches river reach in and places the upper reaches of upper reaches cofferdam in, and the diversion export is arranged the low reaches river reach in and is placed in the low reaches of low reaches cofferdam in, is equipped with the diversion channel between diversion tunnel and the low reaches cofferdam. The utility model can ensure the ecological flow required by the river reach between the downstream cofferdam and the diversion tunnel outlet, and avoid causing the dehydrated river reach; the structure has the advantages of small risk, simplicity, practicability, convenience, practicability and low cost, can not leave the defects of the permanent building, and is worthy of popularization.

Description

A structure for providing ecological flow in downstream reaches of hydropower projects

technical field

The utility model relates to the technical field of water conservancy and hydropower engineering, in particular to a structure for providing ecological flow in the downstream section of the water conservancy and hydropower project.

Background technique

In recent years, with the continuous improvement of my country's environmental protection requirements for water conservancy and hydropower projects, the issue of ecological flow discharge from reservoir projects has become a focus of environmental protection authorities. During the construction of water conservancy and hydropower projects, relying on staged cofferdams or diversion tunnels for diversion will generally not cause dehydration in dehydrated river sections. At present, there are many schemes for releasing ecological flow through diversion tunnels during water storage period and operation period of water conservancy and hydropower projects. (3) Set holes and electric butterfly valves on the steel gates of the diversion and drainage structures, or control the opening of the gates by partially opening the imported steel gates. Effectively meet the downstream ecological water demand. In engineering practice, it has been found that due to the constraints of the topography and geology of the river section where the project is located, the outlet of the diversion tunnel of some water conservancy and hydropower projects is far away from the downstream cofferdam, and the distance can reach hundreds of meters or even thousands of meters, which is easy to cause downstream cofferdams. Dehydration occurs in the section from the weir to the outlet of the diversion tunnel, which seriously affects the aquatic ecological environment of this section. However, this problem is often neglected and must be paid great attention to.

Utility model content

The utility model aims to provide a structure for providing ecological flow in the downstream section of the water conservancy and hydropower project, so as to solve the problem of dehydration in the section between the downstream cofferdam and the outlet of the diversion tunnel that may be overlooked in the prior art, and it is convenient and easy to implement , scientific and reliable advantages.

The utility model is achieved through the following technical solutions:

A structure that provides ecological flow in the downstream section of a water conservancy and hydropower project, including an engineering dam that divides the river into an upstream section and a downstream section, and upstream and downstream of the engineering dam are respectively provided with an upstream cofferdam and a downstream cofferdam Weir, diversion tunnel is set between the upstream section and the downstream section, the diversion entrance of the diversion tunnel is placed in the upstream section and placed upstream of the upstream cofferdam, and the diversion outlet is placed in the downstream section and placed downstream Downstream of the cofferdam, a diversion channel is provided between the diversion tunnel and the downstream cofferdam.

The entrance elevation of the water diversion channel is lower than the bottom elevation of the diversion tunnel there, and the entrance elevation of the water diversion channel is higher than the outlet elevation.

The beneficial effects of the utility model are:

Compared with the prior art, the structure provided by the utility model to provide the ecological flow in the downstream section of the water conservancy and hydropower project can ensure the required ecological flow in the section between the downstream cofferdam and the outlet of the diversion tunnel, avoiding the dehydration section, It solves the problem of dehydration of the river section between the downstream cofferdam and the outlet of the diversion tunnel that may be neglected in some projects at present; and the structure has low risk, is simple, easy to implement, convenient and practical, and low in cost. It will leave defects to the permanent building itself, and it is worth promoting.

Description of drawings

Fig. 1 is the layout diagram of the utility model;

In the figure: 1-engineering dam, 2-upstream cofferdam, 3-downstream cofferdam, 4-diversion inlet, 5-diversion tunnel, 6-diversion outlet, 7-diversion channel, 8-upstream river section, 9- Downstream reach.

detailed description

Below in conjunction with accompanying drawing, the technical scheme of the present utility model will be further described, but the required protection scope is not limited to the description;

As shown in Figure 1, the structure provided by the utility model to provide the ecological flow of the downstream section of the water conservancy and hydropower project includes an engineering dam 1, and the engineering dam 1 divides the river into an upstream section 8 and a downstream section 9. An upstream cofferdam 2 and a downstream cofferdam 3 are respectively arranged on the upstream and downstream of the dam 1, a diversion tunnel 5 is provided between the upstream section 8 and the downstream section 9, and the diversion entrance 4 of the diversion tunnel 5 is placed in the upstream section 8 is placed upstream of the upstream cofferdam 2, and the diversion outlet 6 is placed at the downstream section 9 and downstream of the downstream cofferdam 3, and a water diversion channel 7 is provided between the diversion tunnel 5 and the downstream cofferdam 3.

The entrance elevation of the water diversion channel 7 is lower than the bottom elevation of the diversion tunnel 5 there, and the entrance elevation of the water diversion channel 7 is higher than the outlet elevation.

As shown in Figure 1, the technical solution of the present utility model is mainly during the construction diversion period, or when the ecological flow is still discharged through the diversion tunnel 5 after the diversion inlet 4 is lowered to store water, the water diversion channel 7 built in advance The water discharged from the diversion tunnel 5 is diverted to the downstream cofferdam 3, and then flows into the river channel to discharge the ecological flow to the dewatered river section in the downstream river section 9. The flow capacity of the diversion channel 7 should meet the requirements of the dehydrated river section. Minimum ecological flow requirements. The inlet position of the water diversion channel 7 should be determined by hydraulic calculation, or arranged at the diversion outlet 6, or arranged at a certain position inside the diversion tunnel 5, but it should be ensured that the inlet elevation of the diversion channel 7 is lower than the diversion outlet there. The elevation of the bottom of the tunnel 5 is lowered, and the inlet elevation of the water diversion channel 7 is higher than the outlet elevation, that is, the slope of the water diversion channel 7 is opposite to that of the river course.

Due to the adoption of the above-mentioned technical scheme, during the diversion period of the tunnel during the construction period, and when the ecological flow required for the downstream river section is still released through the diversion tunnel 5 after the diversion tunnel 5 is lowered to store water, the water diversion channel 7 is used to divert the downstream river section 9 The required ecological flow is led to the downstream cofferdam 3 upstream of the diversion outlet 6, and then flows into the river, thereby ensuring the ecological flow required for the river section between the downstream cofferdam 3 and the diversion outlet 6, and avoiding the dehydration of the river This section solves this problem that some projects may ignore at present.

Claims (2)

1. one kind provides the structure of Hydraulic and Hydro-Power Engineering lower reache ecological flow, comprise engineering dam (1), river is divided into upper reach (8) and lower reache (9) by engineering dam (1), upstream cofferdam (2) and downstream cofferdam (3) is respectively arranged with at engineering dam (1) upstream and downstream, diversion tunnel (5) is provided with between upper reach (8) and lower reache (9), the directed fluid inlet (4) of diversion tunnel (5) is placed in upper reach (8) and is placed in the upstream of upstream cofferdam (2), diversion outlet (6) is placed in lower reache (9) and is placed in the downstream of downstream cofferdam (3), it is characterized in that: between described diversion tunnel (5) and downstream cofferdam (3), be provided with water-drawing channel (7).

2. the structure that Hydraulic and Hydro-Power Engineering lower reache ecological flow is provided according to claim 1, it is characterized in that: the entrance elevation of described water-drawing channel (7) is lower than diversion tunnel (5) Bottom Altitude at this place, and water-drawing channel (7) entrance elevation is higher than outlet elevation.