What are the working principles and characteristics of the package sewage treatment plant？

Summary

The package sewage treatment plant  includes eight main units of water distribution, reaction, sedimentation, filtration, water collection, mud collection and automatic backwashing, which are equipped with PPC slant tube filler and various specifications of refined filtering materials, the main shell of the device is made of carbon steel, and the interior and exterior are treated with special coating for anti-corrosion, with long service life, wide range of use and excellent performance.

The package sewage treatment plant has advanced technology, novel design, compact structure, area saving and investment, simple management, easy operation, treatment of raw water turbidity is less than 3000mg/L (short time up to 3000mg/L), the effluent turbidity is not less than 3 mg/L, disinfection by chlorination, can reach the international water standards.

Working Principle

The package sewage treatment plant: It consists of coagulation pool, sedimentation pool, filtration pool, water quality stabilization dosing device, backwashing device, water pump and electrical control cabinet.

1、Coagulation pool: WTH pipeline static mixer is used to automatically mix coagulant by water power. The raw water with coagulant enters the coagulation pool by the inlet pipe, and mixes with the special eddy reaction and coagulant, so that the suspended matter in the water and coagulant can fully contact and react to form alum. General package sewage treatment plant is used to make water and coagulant mix with eddy reaction, but the effect is unstable by the change of water volume. Also available special mixer stirring, so that the suspended matter in the water and coagulant full contact reaction to form alum flowers, not affected by changes in water volume.

2、Sedimentation pond: After the water is coagulated with coagulant to form alum, it flows to the sedimentation pond of the equipment to be precipitated, the sedimentation pond adopts inclined pipe sedimentation method, the surface load is 7-8m³/㎡.h. After the trapezoidal inclined plate sedimentation chamber to complete the solid-liquid separation, the precipitated sludge is discharged into the mud hopper.

3、Filtration pond: the water flows to the filtration pond after sedimentation. The structure of the filter pond is cloth water pipe at the bottom, quartz sand in the middle and white coal at the top. The filtration speed is 7~10m/h, flushing intensity 14~16L/㎡.s, and finally the clear water flows to the clear water tank after disinfection and drinking. The backwash cycle of the filter tank is about 12 hours, and the backwash time is 5-10 minutes. The filtration part adopts polystyrene bead ball filtration.

Performance advantages

1. the package sewage treatment plant itself from the reaction, flocculation sedimentation, water collection, water distribution, filtration, body backwashing, mud discharge and a series of operating procedures, have achieved the effect of fully automatic operation, the duty staff as long as the regular water quality monitoring, no need to operate the water purification device management.
2. High concentration flocculation layer can make the impurity particles in the raw water get sufficient collision contact between them, and the chance of adsorption increases, so it can adapt to various raw water temperature and turbidity, and the removal rate of impurity particles is high, and the algae removal function is good under the condition of adding algaecide.
3. The rapid sludge concentration chamber and adjustable automatic mud discharge system can ensure the timely removal of excess sludge, thus ensuring stable impurity particle removal rate.
4. efficient flocculation and sedimentation effect, so that the sedimentation water quality has been maintained in good condition.
5. The novel and original water collection system and the most economical water collection head make the water collection more uniform and effective, which not only improves the volume utilization factor, but also its water collection head is extremely small.
6. package sewage treatment plantautomation, that is, to ensure the high efficiency of the water purification system filtration (in the original water turbidity less than 3000mg / L, the filtered water turbidity can be maintained at about 5mg / L), but also automatic backwash, without another backwash pump or air compressor and other electrical equipment, and save a lot of infrastructure investment and daily operation, maintenance, repair, maintenance costs, long service life.
7. The equipment has low water consumption rate (about 3%), which plays a positive role in saving valuable water resources.
8. Small footprint, compared with the general water purification structures, can save more than 50% of the footprint, the height of about 4.35 meters, indoor and outdoor can be placed.
9. easy to expand, renovate, relocate or move to reuse.
10. short construction period, a quarter of the construction cycle of conventional clarification and filtration facilities.
11. water purification outlet height ≥ 2m, clear water pool can be built semi-ground type, clear water pump for self-infusion suction, while more reliable operation.

Technical parameters

Take the 200m³/h package sewage treatment plant as an example, its technical parameters are as follows:

Treatment capacity: 200m³/h

Material: genuine factory plate Q235 steel

Coagulation pool residence time: 6.5min

Filtration zone flow rate: 7.2m/h

Sedimentation tank surface load: 7-8m³/㎡.h

Filter layer thickness: 1200mm

Flushing intensity: 14~16L/㎡.s

Washing time: 5-10min

Total residence time: 40-50min

Inlet water pressure: 0.06-0.20Mpa

 Reaction area:

Water distribution method: perforated pipe water distribution

Residence time: 19min

  Sedimentation area:

Sedimentation mode: inclined pipe sedimentation

Slant pipe specification: Ф50mm into horizontal 65 ° angle installation

Ф35mm into the horizontal 65 ° angle installation

  Filtration area:

Filter material: according to the requirements of the filtering area grade table

Water distribution method: porous plate with drainage cap

Operation mode: gravity flow

Backwash mode: siphon backwash

Inlet pipe: DN200

Outlet pipe: DN200

Drainage pipe: DN600

Mud drainage pipe: DN300

Pressure water pipe：DN80

Structure and material

1.package sewage treatment plant

The package sewage treatment plant contains all the main nuclear attachments and materials (water purifier main body, inclined plate, filter media, mud discharge system, water discharge system, inspection channel, inlet and outlet valves, etc.).

2. Raw water tube filter

Raw water pipe filter 2 sets, respectively installed in the two water purifiers on the inlet branch pipe.

3. Tube static mixer

Static mixer has simple structure and small footprint. It is made of glass steel, which is easy to process, durable and corrosion resistant. It adopts advanced foreign technology, with good mixing effect and small head loss; it is connected in series in the conveying pipeline, which does not occupy another area and saves engineering land area; there are no moving parts, and the components only have hydraulic wear and tear, which has a long life and requires no maintenance. Mixer diameter according to the economic flow rate to choose, generally calculated by 0.9-1.2m / s; pipe diameter greater than 500mm maximum flow rate of up to 1.5m / s calculation. When available, the pipe diameter will be enlarged by 50-100mm, in order to reduce head loss. Mixer section number of basic combinations of three sections to consider, head loss of about 0.4-0.8 m. Can also increase or decrease the number of sections according to the case of mixed media. The water pressure in the mixer tube is considered by 0.1kg/c㎡, and the equipment can also be processed according to the actual pressure.

4. Dosing system

Dosing system uses metering pump or flow meter to add coagulant and coagulant. It is used for alkaline aluminum chloride dosing and has a self-flushing device. The dissolution tank is mechanically stirred, and the storage volume is available for at least 18h, including valves and electrical control equipment. Each set of dosing device is individually assembled on its own combination frame, so that the dosing pump, dissolution tank, buffer, filter, pipeline, valve, etc. form an independent whole. The main materials of dosing equipment are made of steel compound glass steel and other materials. Equipment using electric arc (argon arc welding) welding, in the case of checking the quality of the weld seam no problem; inside and outside the equipment de-slag polishing; water pressure test without leakage conditions; in the factory by the appearance inspection, water pressure test, site acceptance test and the necessary corrosion resistance test, and can be used in a certain state of overload good.

5. Disinfection system

It adopts metering pump for dosing, considers dosing before and after, uses bleaching essence (or bleaching powder) for dosing, and has self-rinsing device. The dissolution tank is mechanically stirred, and the storage volume is available for at least 18h, including valves and electrical control equipment.

6. Backwashing system

The backwashing system includes a full set of equipment such as pumps, air pumps, valves and electrical control equipment. It adopts double-ring multi-spout rotary flushing system, which has good flushing effect and low water consumption.

Equipment anti-corrosion

The thickness of the steel plate of the package sewage treatment plant components is 10mm, and the interior of the body is painted with two courses of 50-60um red-dan primer and three courses of epoxy resin paint, and the exterior of the inner body: two courses of 50-60um red-dan anti-rust primer and two layers of green paint for the top coat.

Operation and Precautions

1, frozen areas package sewage treatment plant should be installed indoors, non-frozen areas can be installed outdoors, but must add the top cover cover to avoid contamination of water quality.

2, the installation of package sewage treatment plant will be placed on a flat site to ensure that the normal water uniformity. Various pipeline connection gate valve should be free of air leakage and water seepage and be excluded.

3, before the operation of the equipment, must eliminate impurities in the pool, etc., pay attention to the inlet and outlet pipes to prevent blockage phenomenon.

4, serious pollution of the water source, containing organic matter or algae more, chlorination can be used to reduce the chromaticity, destroy the colloid in the water and remove the odor, prevent the pool from reproducing algae and moss, etc.

5, before starting the equipment, half open the inlet valve, after starting the pump, should first use a smaller amount of water normally open flow rate, and increase the amount of coagulant dosing. 60 minutes later, then open the large inlet valve, increase to the design water volume, reduce the amount of coagulant dosing.

6, the first time the equipment backwash, should adjust the backwash gate to a given strength (to not wash out the filter material mainly), and control the backwash time.

7, should regularly open the sewage pipe valve, the sedimentation tank sludge discharge.

8、Water quality measurement items:

(1), depending on local conditions regularly by the relevant units of raw water and water quality for comprehensive analysis and testing.

(2), the water plant daily raw water, clarifier water and filter water turbidity measurement.