Example of course work on water intake facilities

Contents

CONTENTS

Paper

Introduction

Source Data

1. Design of river water intake facility

1.1. Selection of location and type of river water intake facility

1.2. Development of water intake structures and layout of main equipment

1.3. Hydraulic calculation of water intake structures

1.3.1. Tip Design and Inlet Calculation

1.3.2. Calculation of gravity lines

1.3.2.1. Head losses in gravity lines at UNV (operation at low water level)

1.3.2.2. Head losses during emergency operation of water intake during shutdown of one line at VHF

1.3.2.3. Head losses at passing of design water intake flow rate along one line at UVW (operation in flood)

1.3.3. Design of holding grids

1.3.4. Sizing of onshore pit in plan during "dry" pump installation

1.3.5. Determination of water levels in the shore pit

1.4. Determination of main technical parameters of operation of the pump station of the first lift

1.5. Sizing of Shore Pit in Plan with Wet Pump Installation

2. Design of underground water intake source

2.1. Selection of water intake location (arrangement of structures)

2.2. Calculation of groundwater intake

2.2.1. Well calculation

2.2.2.Selection of filter type and its calculation

2.3. Determination of required pump equipment supply and head values, as well as pump immersion depth

2.4. Measures for sanitary protection of water intake from underground water supply source Conclusion

Literature

Introduction

Improving and preserving the health of the population and, in general, the safety of the nation is the main goal, the solution of which is to provide the population with quality drinking water, which is a priority social problem of any country. In solving the general problems of drinking water supply, the tasks of optimal design, construction and operation of drinking water supply systems from underground sources and their elements play an important role.

Surface and underground water intake facilities are considered in this course work.

Water intake facilities are a complex of engineering hydraulic structures designed to take the estimated flow rate of water from a water source, protect the water supply system from ingress of debris, sediments, ice, algae, fish, as well as for preliminary water treatment.

Underground water intakes are of the following types:

Tubular boreholes (boreholes);

Mine wells;

Horizontal catchments;

Ray catchments;

Structures for capturing spring water.

Groundwater lies at various depths and in various rocks. Having high sanitary qualities, these waters are especially valuable for the drinking water supply of populated places.

Design input for Open Source Water Intake Facility

Water intake facilities are located in the river alignment at a distance from the settlement. Design daily flow rate Qmaxday = 2980 m3/day.

The length of the first rise water ducts is -250 m.

River data:

Lower water level (low water) (UNV) - 87.5m,

Upper water level (flood) (UVV) - 90 m,

Design ice thickness d = 0.22 m,

Design water speed: at vmin vmin = 0.75m/s ,

at HVV vmax = 1.3 m/s,

Sand wash particle diameter d = 0.1 mm,

Absolute elevation corresponding to zero - 84 m,

Landmark of onshore well-91 m,

In accordance with the design data, the following structure is accepted: water intake structure, submersible pumps, water pipelines of the first lift .

Since the river is not navigable, the banks are gentle, the depths are small, a channel-type water intake with an unprotected tip is designed.

Design Basis for Underground Water Intake Facility

Water intake site elevation, Z2 = 100 m,

Water stop roof elevation, Z3 = 80.9 m,

Water stop sole elevation, Z4 = 54 m,

Bottom elevation of aquifer, Z5 = 29.1 m,

Static water level elevation, Z6 = 87.4 m,

Permissible reduction of static level: Sdop = 23.4 m

Aquifer rock - fine sand,

Consumption for drinking needs Qmaxsut = 4730 m3/day.

Water elevation in the 104.6m filtration distribution bowl

Design of river water intake facility

1.1. Selection of location and type of river water intake facility

For proper selection of water supply source, design and construction of water intakes it is necessary to carry out topographic, hydrogeological and geological surveys. Research reveals:

- consumption regime and water balance by source with forecast for 15... 20 years;

- quality characteristic of water in the source and forecast of its possible change by 15... 20 years.

When designing water intakes, consider:

- requirements to water quality by the consumer;

- Sanitary requirements and requirements of other interested bodies for the use and protection of water resources;

- Feasibility assessment of water use conditions of various sources.

Based on hydrological conditions, water receiving facilities are located in places where sediments and a large depth of the river are not deposited, that is, off concave banks, while it should be borne in mind that the concave banks of the river are subject to erosion and destruction, and straight sections are unreliable due to the formation of rifts on them. The selected section of the channel should not be located on the roll and should not have sharp local narrows, sweeps, swifts, fences (i.e. exits of rock thresholds in the bottom of the channel), islands, spits.

Water intake facilities cannot be located near the convex shore, where sediments are deposited, in places of possible formation of shuga and underwater ice, in the waters of movement of ships, rafts, in the range of sediments, in areas of winter fish, etc.

The place of water intake should have calm and favorable topographic forms of the coast without steep slopes, floodplains, ravines, etc. Water intakes cannot be located in the flood zone of surface structures with flood waters, in seismic and other areas where landslide phenomena are possible, as a result of which structures are destroyed.

Sanitary conditions are important when choosing a water intake location. The water intake point for drinking water supply shall be located upstream of the river from settlements, livestock farms, waste water outlets, ship parking lots and barges.

The general scheme of water intake structures from surface water supply sources has two types (coastal and channel), which differ between themselves in the place of water intake relative to the coast. The most common two arrangements are combined and separate, differing in the location of the pumping station relative to the shore well.

Coastal water intake is arranged in the presence of large depths near the coast and with its steep shape. Water is taken directly at the shore.

Channel water intake is arranged if sufficient depths for water intake take place at a significant distance from the river bank, that is, the river has gentle banks.

Preference should be given to channel and shore schemes with a combined layout. They are used for medium and high-capacity water intakes.

Water intake structures of the third type - bucket, arranged to improve the conditions for receiving water and reduce the amount of suspended substances in water. Such a water intake is an ordinary channel or coastal, arranged on the shore of a special structure called a "bucket." Depending on the direction of water entering the ladle, the following types of bucket water intakes are distinguished:

- ladle with top power supply;

- ladle with lower power supply;

- ladle with double-sided power.

We take channel water intake for design, since the river is not deep and its banks are gentle.

1.2. Development of water intake structures and layout of main equipment.

In accordance with the design assignment, the design of the combined type river water intake facility should be carried out.

The water intake equipment includes:

grids protecting the receiving holes from ingress of sludge and floating bodies;

fish protection nets removable or nets with flushing devices;

lifting, transport and washing devices for lifting and washing grids;

Pumps or ejectors for cleaning coastal wells of sediment;

pumps of the 1st lift;

auxiliary pumps (drains for filtrate pumping, vacuum pumps for pump start-up), as well as fans for creation of artificial air circulation;

lifting and transportation devices and devices for installation and dismantling of equipment and communications;

electrical equipment;

gates (shields, throttles, gate valves, etc.) for control of communications and water intake equipment;

According to the mutual location of the shore pit and the pumping station, the water intake can be of separate and combined types.

In channel water intakes for receiving water, the ends of gravity pipes, which have an expansion at the entrance in the form of funnels or funnels, are brought into the river bed, and embedded in special concrete chambers (caps) to protect against damage and prevent movement along the bottom. The receiving caps can also be pile.

The tips of small and medium capacity channel water intakes are usually constantly flooded and can be of protected and unprotected types.

We use heads of unprotected type (with sufficient depth and light water intake conditions), since water is taken from non-navigable and non-saline rivers. To reduce clogging, we close the inlet holes with grids.

1.3.4. Sizing of onshore pit in plan when pumps are "dry."

The site for the construction of the onshore water intake (well) should be selected higher at 0.5... 1.0 m of the design HVAC elevation. The depth of the water intake well of the coastal water intake is taken in such a way that it is not washed by the flow of the river. The coastal well consists of ground and underground parts. The underground part of the well is usually round in plan, has two intake and two suction sections. At least two sections are installed in the intake compartment to ensure its uninterrupted operation. The height of the window and grid is selected from the calculation data. The dimensions of the well in the plan are assigned based on the condition of equipment placement in the receiving and suction sections (compartments) and are structurally accepted 3; 3,5; 4,0; 4.5 m, etc.

The size and number of suction compartment sections depends on the diameter of the suction pipes and their number. The number of sections shall be at least two for pump stations of category I and II. When installing large pumping units, the number of sections and pipes is taken equal to the number of pumps. Two or more small diameter suction tubes may be arranged in one section, the distance between which shall be taken according to Table 5, Annex 1. The layout of the pipes in the plan dictates the size of the suction compartment sections. At the same time, the intake compartment is recommended to take a slightly larger size in plan than the suction compartment.

Gravity pipe diameter, type and dimensions of flushing equipment are defined above. When designing suction pipes, the requirements are taken into account: the pipes must not have sharp turns and sudden extensions, the lines are determined by the calculated flow rate of one section and the speed in the suction pipe Vvs:

Design of underground water intake facility

2.1. Select Well Location

Selection of water intake place is carried out on the basis of hydrogeological and geological conditions, natural characteristics of a particular area on the basis of technical and economic considerations. Water intakes for household and drinking water supply are located in places that meet sanitary requirements, outside the pockets of groundwater pollution (settlements, enterprises that can discharge harmful and contaminated effluents, livestock farms, away from cemeteries). A sanitary protection area shall be arranged at the place where water intakes are arranged.

The site is chosen according to trebovaniyamtkp 454.01-30-2009. Taking into account the sanitary requirements, the possibility of organizing a sanitary protection zone, the convenience of water intake maintenance, the connection of wells to the water supply network, the installation of water supply facilities and others, we choose a place above the settlement, outside the zones of possible contamination.

In accordance with the selected structures, we accept the following water supply scheme: water intake by a group of wells - water supply through the prefabricated water pipelines to the clean water tank - water supply by the pump station of the II rise through water pipelines to the water tower - water supply to the network.

Conclusion

In the course design, taking into account the initial geological and topographic data, qualitative indicators of aquifers, two water intake structures were designed: from surface and underground sources.

For the coastal type water intake facility, the dimensions of the holding grille 400x500 mm were calculated. You have assigned plan dimensions to the shore structure. According to the results of calculation of supply (q = 9.5 l/s) and head (H = 23.07 m) of the pump station of the first lift, the corresponding submerged pumps were selected.

When designing the water intake structure at the underground source, a strainer with mesh No. 12/90 was adopted .

According to TKP 454.01-30-2009 (item 6.2.4.2, Table 6.1) 5 working wells and two reserve wells were accepted. The actual well flow rate is qfact = 946m3/day. Based on the results of calculation of the well hourly flow rate and the pump head installed in the well for constant operation, the corresponding submersible pump of the grade ECV84060 was selected. Measures for sanitary protection of water intake have been developed.