precast sewage pump station - basics of carrying off and pumping of wastewater
Pumping stations are fundamental elements present in urban sewage networks , settlements , villages and industrial plants. Nowadays It has been solved many problems associated with the construction and operation of the pumping station. Currently, these devices are working automatically , requiring only periodic service. Modern solutions of pump impellers allow the omission of the most troublesome element in the operation of the old pumping station - the bars and the economy of its wastes, which also allows the omission of 50 m zones of sanitary protection. Customizing environmental legislation to European standards, forces on all villages above 2000 population to have a sewage system . Therefore , although actually the largest quantities of municipal wastewater and industrial are collected in cities , it is adapting to the requirements of the European Union , gradually increase the amount of sewage from rural areas to be made to the sewer system. In practice, the most economical system, especially in rural conditions is a gravity-pressure sewer where sewages flow by the gravity into pumping station tanks and then are pressed for considerable distances . Proposed by JBK-SYSTEM sewage pumping stations are complete , fully automated devices that do not require constant maintenance , designed for pumping municipal wastewater , drainage and rainwater in various sewage systems .
The most important element in the construction of the sewer system is without a doubt the design phase. Precise determination by the designer of all the parameters and requirements for the future system of drains, to avoid confusion during the auction, or additional costs at the task realization. Meet the clients requirements we offer a free consultation in the selection of equipment pumping stations.
SELECTION OF TYPE PUMPING STATION
JBK -SYSTEM , like other domestic or foreign companies, has a range of proven technical solutions for pumping station. On the basis of the experience gained in the construction and operation of the pumping station can be concluded that the optimal solution is prefabricated sewage pumping station, recessed in the area and equipped with submersible pumps . Alternatively submersible pumps can be replaced by self-priming pumps or shaft pumps . This choice involves with the danger of freezing in the winter which entails costs for the heating system. Operation of self-priming pumps can also hinder the presence of solids in the sewages , which may block the suction line . In this case, you must reckon with the possibility of building grids to trap solids larger than the capacity of the pump suction port . This solution puts into question the possibility of unattended operation , which is the standard for the use of submersible pumps .
SELECTION OF PUMP
Pump selection is integrally connected with the discharge pipe dimensions and geometry (geodesic) lifting height. In the discharge pipeline should be maintained a minimum flow velocity V = 0.8 m / s, providing self-cleaning of the pipeline.
Basic data when selecting a pump are:
- The amount of sewage
- Geometric (geodetic) lifting height
- The length and diamter of the discharge pipeline
- Number of bends in the discharge line.
Determination on the basis of basic data their computational efficiency of the pump and the calculation of the characteristics of the system, allows to select pump with high-efficiency of electric and hydraulic . The choice of pump used should be related to the type of sewage and a maximum amount of solids contained in the sewages.
There are three basic types of rotors used in pumps:
- Pumps with channel impeller - allowing pumping of liquids with solids and small amounts of sand and fibrous materials. With this type of rotors we obtain the highest efficiency of the pump relative to the energy collected from the network.
- Pumps with open impeller (vortex) for pumping almost all types of waste water (remember to choose the free movement of the rotor chamber min. 80mm for typical waste water treatment)
- Pumps with grinding devices - which permits fragmentation of solids and forcing them by pipelines with diameter smaller than 80 mm. When choosing a pump with cutting devices should be remembered that the sewer should leakproof what will minimize the ingress of sand which damages the cutting surfaces of grinding equipment.
Selection of pumps for pumping of solids and fibrous or their ability shredding, allows to avoids the use of a pump station grids and related protection zone.
The minimum flow velocity in the discharge pipe of 0.8 m / s - essential for self-cleaning discharge line - dictates the diameter of the pipeline, and hence the need for pumps with shredding machine for diameters less than 80 mm.
The present division is very general. In each situation must be considered separately the quantity, quality and composition of the sewages. Especially pay attention to industrial waste, which can be characterized by a very high aggressiveness or volatility in terms of quality and quantity.
SELECTION OF TANK
About the dimensions of pumping station decide first of all:
- Maximum inflow per hour of sewage and associated with it pumps efficiency
- Ground level where the pumping station is located
- Ordinate of the bottom edge of the inflow pipe (in the case of more than one inflow pipe, ordinate of the lowest one)
- The ordinate of axis of the discharge pipeline in the pumping station
- The diameter of the discharge pipeline, if it is already located
- Ordinate of groundwater to calculate the displacement ring
- Number of installed pumps and their size
- The minimum level of the liquid surface, usually set so as not to discover the pump motor
- The height of the working chamber determined based on the estimated number of pump starts per hour (preferably from 8 to 24 starts per hour and up to 40 for pumps Wilo production)
- The elevation of the reservoir pumping station above the ground level.
Above parameters determine the diameter and depth of the tank of pumping station. Of particular importance in the selection of the dimensions of the tank is to determine the volume of the working chamber. Maximum number of starts pump should not be greater than the allowable number of starts reported by the manufacturer.
CONTAINER SEWAGE PUMPING STATION - CONSTRUCTION
Assembled by JBK-SYSTEM Container sewage pumping stations are adapted to the individual needs of each client, in agreement already existing standards, or presentation of its own concept approved by the Project Office. The tank of pumping station is made from materials already tested and guaranteed one hundred percent leakproofness.
- glass reinforced polyester
- polymer concrete
- diameters from 600 to 2500mm
The pumping station is equipped with one or more submersible pumps with hooks to enable automatic connection to the discharge pipe through the coupling rate, without having to enter into the tank. Discharge pipeline is made of stainless steel or PVC, equipped with a ball non-return valve and flanged gate valve figs 111 or knife gate valve. Other elements such as the platform, ladders, ventilation elements are made of stainless steel, aluminum or PVC.
All the equipment are selected from stainless steel and corrosion-resistant materials, ensuring a long service life without major maintenance.
The basic element in pumping station is control system and surveillance devices installed in it. Basic equipment of the switchboard in the following items and equipment each time should be coordinated with the future exploiter:
- Main switch
- Overvoltage protection
- Motor circuit breakers MBS for pump protection
- Contactors or Soft-Starts to supply power to the pump engines
- Float switches for detection:
- Dry run level
- Start or Stop level
- High level (emergency)
- Anti-condensation heater with thermostat
- Ammeter (in one phase) for measuring the current of each pump
- PLC controller with integrated operator panel executing the following functions:
- Aligning the work time between the pumps (alternation)
- Counting time for each pump
- Pump Control ( Manual - Stopped - Automatic)
- Controlling thermal protection and overcurrent of pumps
- Monitor the status and the presence of voltage in switchboard
- Deleting an acoustic signal informing about emergency conditions at the facility.
- The system of acoustic signaling and light signaling failure and high level alarm, powered with maintenance-free gel battery
- No-voltage signals derived onto a terminal strip informs about:
- sum of failures of object
- high level
- Gel battery to maintain operation PLC controller ,signaling system of alarm states and the work of the radio transmission.
- 12/24VDC stabilized power supply for battery charging and powered automation components.
- Single-phase repair socket 230VAC/10A protected by RCD circuit breaker.
- The sensor of control and the presence of phases.
- The security module batteries from deep discharge.
- Complet set of
- The foundation of a polyester Class IK10.
In some cases there is a need to equip the sewer system in specialized equipment such as:
- The transmission of data (monitoring)
- Electromagnetic flowmeter
- Slot generator
Please note that, prior to the start of the investment, you should anticipate additional equipment at the design stage and later auction, which will guarantee the security of funds for this purpose.
At the first start of pumping sation should first be checked the compatibility of connection of devices to the instalation with the supplied wiring diagram and instruction manual of each device. First start of the pumps should be on the water. In the first phase of commissioning, set the levels of activation, off , dry running and high level alarm. All commissioning works of pumping sation should be completed by protective measurements, which will be the annex to the protocol.
Personnel conducting the exploitation of the pumping station shall operate in accordance with the applicable safety regulations and have the appropriate permissions. Each facility should be equiped in the book of events.
It is important that the staff which operate the pumping station was familiar with the installed equipment, what is made possible by the training organization in start-up phase and ongoing collaboration.
- Conducting ongoing training
- Warranty and after warranty service
SUMMARY - CONCLUSIONS
Optimal selection of equipment must be linked to cooperation of designer, investor, together with the future user and the manufacturer. In this case, we can only ensure the smooth and economical operation of the system.
Company JBK-SYSTEM in addition to manufacturing, design or sales, also provides full warranty and after warranty service for all products. We have a well-trained and equipped service. In addition, we conduct ongoing monitoring and maintenance of sewage pumping station, which is generally more advantageous economically than keeping this to its own services.