The present situation and development direction of sewage treatment are analyzed

SS suspended matter refers to a solid substance suspended in water, and the greater the NH3-N value, the higher the degree of pollution.

5. Experimental instruments, instruments, implementation standards and principles

5.1 Experimental technology and implementation standards

This experiment adopts A20+MBR wastewater treatment process, implements G18918-2002 Grade A standard, the average daily treatment capacity is 35,000 cubic meters, the average comprehensive treatment capacity is 35,500 cubic meters, and the designed treatment capacity is 40,000 tons per day.

5.2 Equipment configuration of MBR process sewage treatment device

1. 1 set of grid pool (spacing 2mm), 1 set of aerated sand settling pool, membrane bioreactor: transparent plexiglass material, thickness 12mm.

2, vertical flow initial sedimentation tank 1 set: transparent plexiglass material, thickness 8mm, volume 25L.

3, UV sterilization device 2 sets: UV lamp 2 sets, plexiglass column 2 sets, shading aluminum platinum paper 2 sets.

4, the original water tank, the middle water tank (30L) and the clean water tank are each 1: white PP board, thickness 12mm, the bottom plate is installed with a vent valve, easy to drain the water.

5, mixing motor 1 set (power 20W, speed 110rpm), 304 stainless steel mixing paddle 1 set.

6, anti-corrosion lifting magnetic pump 3 sets, flow: 15 ~ 18(L/min), head: 2.6 ~ 3.3(m) power 25W.

7, 1 aeration pump, (power 220V, power 60W, maximum gas: 9L/min), including 1 set of aeration pipeline.

8, flat film component 1 set (PVDF flat film, area: 0.1m2/ piece, a total of 10 pieces).

9, water diaphragm pump 1, water flow meter 1, (range 3-30L/H).

10, mixed liquid reflux device: reflux pump 1 set, reflux pipeline 1 set.

11, flow measurement and regulation: rotor flow meter, liquid flow 3 (range 3-30L/H), gas flow 1 (range 100~1000L/h).

12, power control system: double-sided matte spray plastic electric control box 1, leakage protector, voltmeter, button switch with lock, line tube, etc.

13, supporting UPVC connection pipes and valves.

14, stainless steel frame test bench.

5.3 Equipment configuration of A2O process sewage treatment device

1, mixing motor 1: power 35W, speed 100rpm; Stainless steel mixing paddle 1.

2, lift pump 1: flow 1.5T/h, lift 2.8m, power 30W.

3, secondary sedimentation tank: transparent plexiglass material, wall thickness of 6mm, effective volume of 25L.

4, hypoxia pool: transparent plexiglass material, wall thickness of 6mm, effective volume of 20L.

5, anaerobic pool: transparent plexiglass material, wall thickness 6mm, effective volume 15L.

6, aerobic pool: transparent plexiglass material, thickness 12mm, effective volume 45L.

7. 2 sets of mixing device: adjustable speed.

8, the original water tank and the clean water tank each 1: white PP board, thickness 12mm, the original water tank volume 100L, the clean water tank volume 50L, the tank bottom plate is installed with a vent valve, easy to drain the water.

9, return pump 2 sets: flow digital display and stepless speed regulation, with timing quantitative transmission and suction function (prevent dripping), the maximum flow can reach 32L/h and 14L/h.

10, 1 air pump: power 95W, exhaust 95L/min, pressure > 0.035Mpa; 2 aeration systems.

11, flow measurement and regulation: rotor flow meter, liquid flow 1: range 2-20L/H; Gas flow 1: range 0.1-1m3/h.

12, 304 stainless steel table.

13, power control system: double-sided matte spray plastic electric control box 1, leakage protector, voltmeter, self-locking button switch with light, line slot, etc.

14, transparent silicone pipe, valve, elbow.

15, stainless steel frame test bench.

Operating conditions: normal temperature and pressure operation, power supply voltage 220V.

5.4 Experimental Principles

5.4.1 Experimental principle of MBR wastewater treatment process

MBR is a new wastewater treatment process with high efficiency and high function. It uses a membrane separation tool to screen the sludge from the first reaction tank with organic matter, eliminating the need for a secondary sedimentation tank [8]. As a result, the activated sludge concentration is greatly increased, HRT and SRT can be controlled separately, and hard-to degrade materials are frequently used and degraded in the machine. Compared with traditional methods, this MBR method combining membrane with biochemical reaction is effective [9].

mbr process Description:

Raw water → Grid → regulating tank → lifting pump → Bioreactor → circulating pump → membrane assembly → Disinfection device → reclaimed water storage tank → reclaimed water system [10]

The function of the regulating tank is mainly to collect the generated sewage, balance the overall water quality, and adjust the pH in the overall water quality, so as to ensure that the experiment can be carried out smoothly.

The role of the anaerobic tank is mainly to gradually disintegrate large molecular organic matter into small molecules, so that it is easier to handle later, and can also remove local phosphorus.

The main function of the anoxic tank is to remove a series of ammonia containing sewage such as ammonia nitrogen.

Aerobic tank: The degraded organic matter is further degraded into carbon dioxide and water by the aerobic microorganisms in the tank under the condition of aeration and oxygenation, thoroughly decomposing the organic matter, and at the same time, the phosphorous releasing microorganisms absorb phosphorus in excess to remove phosphorus.