Course project on "Waste water treatment technology"

Contents

Introduction

Determination of wastewater flows to the treatment plant

Determination of average concentration of pollution in total runoff

Determination of the required degree of wastewater treatment before its release into the reservoir

Determination of the required waste water treatment by suspended substances

Determination of required degree of waste water treatment by BOD

Determination of required degree of wastewater treatment by oxygen dissolved in water

Determination of the required degree of wastewater treatment by water temperature in the reservoir

Selection of treatment method and composition of treatment facilities. Drawing up a process flow chart for waste water treatment

Description and calculation of the facilities included in the treatment plant

Development of the General Plan of the Treatment Plant

Drawing up a profile in the course of water movement

Conclusion

Literature

Introduction

In recent years, a lot of work has been done in the field of municipal wastewater treatment: new technologies have been developed for wastewater treatment and treatment of sediment generated during the treatment process, new structures and equipment have been created, and new calculation methods have been proposed. However, all this is still imperfect and therefore it is necessary to continue improving the design and estimate business, improve the quality of project documentation, provide for the widespread use of progressive scientific and technical domestic achievements, introduce foreign best practices, and improve the quality of training specialists.

Future municipal and industrial wastewater treatment specialists should have a deep knowledge and capacity to handle the complex tasks of managing water bodies and preventing them from pollution and depletion.

This course project is designed to deepen, consolidate and generalize the knowledge gained during the theoretical training of the discipline, as well as acquire practical skills in the design of urban treatment plants.

Development of the General Plan of the Treatment Plant

When developing the general plan, the following recommendations should be followed:

The location of the individual facilities and the overall layout of the treatment plant shall ensure the best organization of the waste water treatment process; all facilities shall be available for repair and maintenance.

The layout of all facilities should ensure the possibility of construction of a treatment plant in queues and its subsequent expansion due to an increase in the flow of waste water.

The length of communications should be as minimal as possible.

All structures shall be more compact. It is advisable to block individual structures in groups. The recommended building factor is 0.7.

The gaps between individual structures should be minimal and at the same time ensure the possibility of their sequencing.

Previously, they can be scheduled as follows:

for the group of structures of the same name - 2-3 m;

for a group of structures of the same name - 5-10m;

for the group of mechanical and biological treatment facilities - 15-20 m;

for structures and silt sites, taking into account their casing with trees - 2530 m;

for methane tanks, gas golders and other structures (depending on their capacity) - 20-50 m;

for chlorine consumption storage: distance from administrative and domestic buildings - 100 m, from production buildings in which maintenance personnel are permanently located - 50 m, from production buildings in which maintenance personnel are periodically - 30 m.

Transport access shall be provided to each structure for delivery of materials during repair.

Fill and cut shall be specified on the station plot plan. To reduce earthworks, it is economically profitable to observe the equality of their volumes when arranging embankments and excavations.

Structures should be arranged symmetrically, ensuring uniform distribution of waste liquid between individual structures.

In addition to the main structures on the general plan, all auxiliary structures should be applied: a boiler room, repair shops, a garage, warehouses, an administrative building with a laboratory, pumping and blowing stations, a transformer site, local sewerage networks and others.

In the communications of the treatment plant, it should be possible to turn off the work for the repair of groups of structures and individual structures, as well as an emergency release that allows you to turn off the whole station, as a last resort.

The territory of the station has to be protected, arranged well, planted trees and shrubs, is lit and to have roads with artificial coverings and walking paths to each of constructions and buildings.

The area of landscaping should be at least 1520% of the area within the boundaries of the territory of treatment facilities.

Grass lawns and planting of trees and shrubs should be: at the sites at the main entrance and entrance to the territory; along driveways and roundabouts; on sites in the area where administrative buildings and premises, laboratories, recreation places and sports grounds are located; around open structures; on lanes separating sidewalks and footpaths from roads, as well as from structures with harmful allocations.

In areas without solid coating, as well as along the fence of the territory of treatment plants, as a rule, grass sowing should be provided.

Watering cranes should be provided for watering roads and green spaces in the summer.

Vertical layout of the area of ​ ​ treatment facilities should ensure the removal of surface water.

Planning elevations of the territory should be assigned in accordance with the technological requirements for vertical planting of structures based on the conditions for maximum preservation of natural terrain and soil cover, minimum volumes of earthworks, drainage of surface water at speeds that exclude the possibility of soil erosion.

Convenient approaches, platforms, stairs and, if necessary, fences should be provided to the locations of technological equipment at treatment facilities and on networks.

The main entrance, passage and entrance to the territory of the treatment facilities must be located from the side of the main approach and the entrance of workers. Here, outside the fence of the territory of treatment facilities, a site for parking of vehicles should be provided.

On the general plan, horizons and a rose of winds are necessarily applied.

The general plan should be linked to the situation plan.

Conclusion

In the course project, the city treatment plant with a capacity of 29270m3/day was developed. The plant includes mechanical, biological treatment facilities, as well as facilities for decontamination and post-treatment of waste water.

Mechanical cleaning facilities include:

receiving chamber of PK260b grade;

two lattices of the MG9T brand and one reserve;

horizontal sand head with circular movement of water with two compartments of sand heads with a diameter of 6 m;

seven primary horizontal settlers with sizes 22kh6kh3,5m.

Biological treatment facilities include:

four round biofilters in a plan view with a diameter of 31m;

four secondary horizontal settling tanks with dimensions of 31x6x3m.

Decontamination and post-treatment facilities include:

laboratory;

a hole mixer with dimensions of 9.9x2.2x1.6m;

contact tank with dimensions of 18x18x3.2m;

Sedimentation treatment facilities include:

two sands with a diameter of 2.0m;

vacuum filters;

emergency sludge platform with dimensions in the plan 35x75x1m.

Also, auxiliary buildings and structures are provided on the territory of the treatment plant: repair shops, a garage, pumping and blowing stations, an administrative building, and local KNS.