Integrated sewage purification main machine purification-backwashing dual-mode intelligent switching control method

Abstract

This invention discloses an intelligent switching control method for a dual-mode purification-backwashing system in an integrated OGEMS wastewater treatment unit, belonging to the field of automatic control technology for industrial wastewater treatment equipment. The method is executed independently by a local electric controller: in purification mode, the inlet valve is opened sequentially, the booster pump is started after a delay, the dosing pump is activated, the outlet valve is opened, and the purification time is accumulated; after accumulating to a set cycle (adjustable 30 minutes), the pump stops, the valve is closed, and pressure is released after a delay, switching to backwashing mode; the backwash valve is opened, the backwash pump is pressurized, and when the pressure reaches the 0.25MPa threshold, the three-way valve is switched and the sludge discharge valve is opened to discharge sludge for 60-80 seconds; after repressurization, it automatically returns to purification mode; the entire process has graded interlocking protection for low-level regulating tank, low-level clear water tank, abnormal pressure, and high-level sludge tank, and the valves and pumps use AC zero-crossing switching. This invention achieves fully automatic backwashing and sludge discharge of the OGEMS unit, with strict time-sequence interlocking and graded abnormality protection for unattended operation.

Description

Technical Field

[0001] This invention belongs to the field of automatic control technology for industrial wastewater treatment equipment, specifically relating to an OGEMS integrated wastewater purification host with dual-mode intelligent switching control for purification and backwashing, and particularly to a purification-backwashing sequence control, pressure-triggered sludge discharge, and interlocking protection method executed locally by an electric controller intelligent agent. Background Technology

[0002] The OGEMS integrated wastewater purification unit is the core purification equipment for small and medium-sized wastewater treatment plants in industrial parks. Its long-term stable operation relies on periodic backwashing and sludge discharge to remove the flocculated sludge trapped inside the unit and restore its purification capacity.

[0003] The backwashing and sludge discharge control of traditional OGEMS main unit has the following problems: (1) It relies on manual operation or simple timers. The timing of backwashing and the duration of sludge discharge are set based on experience. Backwashing too early wastes clean water and electricity, and backwashing too late causes the main unit to be blocked and the water output to deteriorate. (2) The backwashing process involves multiple devices such as inlet valve, outlet valve, backwash valve, sludge discharge valve, three-way valve, and backwash pump. The timing of these devices must be strictly coordinated. Manual operation is prone to errors. Misoperation may cause the main unit to be pressurized, pumped out, or sludge to backflow. (3) The traditional relay-contactor control circuit is complex. Frequent switching results in short contact life and makes it difficult to troubleshoot. (4) It lacks pressure and level interlock protection. The safety of the equipment cannot be guaranteed under abnormal working conditions.

[0004] Therefore, there is an urgent need for an OGEMS host purification-backwashing dual-mode intelligent switching control method that is independently executed locally by an electric controller agent, so as to achieve fully automatic backwashing and sludge discharge, strict time-sequence interlocking, and abnormal grade protection for unattended operation. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an intelligent switching control method for the OGEMS integrated wastewater purification host in both purification and backwashing modes. The method involves an electric controller intelligent body that performs automatic cyclic control of the host and its supporting valves and pumps in purification mode, switching trigger, and backwashing mode. It also triggers sludge discharge according to pressure threshold and performs graded interlock protection according to liquid level and pressure, thereby realizing fully automatic unattended operation of the OGEMS host.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An intelligent switching control method for dual-mode purification and backwashing of an OGEMS integrated wastewater purification host: In purification mode, the inlet valve is opened sequentially, the booster pump is started after a delay, the dosing pump is linked, the outlet valve is opened, and the purification time is accumulated; after the accumulated time reaches the set cycle, the pump is stopped, the valve is closed, and the pressure is released after a delay, switching to backwashing mode; In backwashing mode, the backwash valve is opened, the backwash pump is started to pressurize, and when the pressure reaches the 0.25MPa threshold, the three-way valve is switched and the sludge discharge valve is opened to discharge sludge for 60-80 seconds. After the sludge discharge valve is closed, the pressure is increased again, and after completion, the pump is stopped, the valve is closed, and the system automatically returns to purification mode; The entire process is executed independently locally by the electric controller intelligent body, and the purification cycle, sludge discharge time, and pressure threshold are adjustable online, and it has graded interlock protection for low level of regulating tank, low level of clear water tank, abnormal pressure, and high level of sludge tank.

[0007] Compared with the prior art, the present invention has the following significant advantages: (1) Fully automatic backwashing and sludge discharge. The purification-backwashing dual-mode automatically cycles and switches according to the set cycle. The multi-valve pump is executed automatically by the intelligent agent in strict sequence, completely eliminating the lag and risk of misoperation of manual operation.

[0008] (2) Precise timing of sludge discharge. Sludge discharge is triggered 60-80 seconds only when the backwash pressure reaches the threshold of 0.25MPa. The intensity of sludge discharge is matched with the degree of contamination of the main unit to avoid insufficient sludge discharge or waste of clean water.

[0009] (3) The equipment is safe and reliable. The regulating tank is low, the clean water tank is low, the pressure is abnormal, and the sludge tank is high, with graded interlock protection to prevent damage to the equipment due to abnormal operating conditions such as pressure buildup, cavitation, and backflow.

[0010] (4) Long life of actuator. The valve and pump switching adopts AC zero-crossing technology to eliminate electric arc and inrush current. Under frequent switching conditions, the switching life reaches 1 million times, and the maintenance cycle is greatly extended. Attached Figure Description

[0011] Figure 1 This is a state machine diagram of the OGEMS main unit's purification-backwashing dual-mode operation. The diagram shows the initialization, standby, influent boost, pH dosing, main unit purification, backwashing, drainage idle, and fault alarm states, as well as the conditions for their mutual transfer, and the parallel operation of the biological DO closed loop and the sludge treatment closed loop.

[0012] Figure 2 This is a timing diagram for the OGEMS main unit's purification-backwash switching process. The diagram shows the timing sequence of the main unit's booster pump, #4 dosing pump, main unit outlet valve, backwash valve, backwash pump, sludge discharge valve, and backwash pressure during the switching from purification mode to backwash mode and the return process.

[0013] Figure 3The diagram shows the structure and interlock protection of the OGEMS main unit. The diagram shows the connection relationship of the OGEMS main unit (10), main unit inlet valve (11), main unit booster pump (12), No. 4 dosing pump (13), main unit outlet valve (14), clean water tank (15), backwash pump (16), backwash valve (17), three-way valve (18), sludge discharge valve (19), sludge tank (20), electric contact pressure gauge (21), and interlock protection (22).

[0014] Figure 4 This is a schematic diagram of the SCADA intelligent monitoring interface of the industrial park wastewater treatment station of the OGEMS integrated wastewater purification host of the present invention; the diagram shows the operating status of each unit of the entire wastewater treatment process, water quality parameters, power consumption statistics curves, AI control operation entry and alarm information.

[0015] Figure 5 This is a partial monitoring interface diagram of the OGEMS integrated wastewater purification host and its supporting valves, pumps, and filter press unit of the present invention; the diagram shows the equipment status, flow rate, and power monitoring parameters of the main unit's purification, backwashing, and sludge discharge related pumps, valves, clear water tank, and sludge tank. Detailed Implementation

[0016] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0017] like Figure 1 As shown, this embodiment takes the OGEMS main unit of the Dongguan Lanhui Hardware Industrial Park wastewater treatment plant as an example. The electric controller intelligent body organizes the control of the whole machine into a state machine: upon power-on, it enters INIT initialization, and after self-test, it enters STANDBY standby mode; INLET_PUMP completes the alternating water intake of the two tanks; PH_DOSING completes the chemical dosing according to the pH closed loop; after the pH reaches the standard, it enters the OGEMS_HOST main unit purification mode; after 30 minutes of purification, it triggers the BACKWASH backwash mode, and automatically returns to purification after backwashing is completed; when the regulating tank is at a low level or the treatment is completed, it enters DRAIN / IDLE drainage idle mode; if any mode exceeds the limit, it enters ALARM fault alarm, and returns to standby after fault reset. BIOCHEM_DO biological DO closed loop and SLUDGE_PROC sludge treatment closed loop operate in parallel with the above state machine and do not block each other.

[0018] like Figure 2As shown, the purification mode sequence is as follows: ① Open the main unit inlet valve; ② Start the main unit booster pump after a 5-second delay; ③ Start the No. 4 dosing pump in conjunction; ④ Open the main unit outlet valve; ⑤ Accumulate running time; ⑥ If the electromagnetic flowmeter detects normal outlet flow, purification continues. After 30 minutes, the backwash mode is entered: ① Stop the main unit booster pump and the No. 4 dosing pump; ② Close the outlet valve and depressurize after a delay; ③ Open the backwash valve; ④ Start the backwash pump to pressurize; ⑤ If the pressure gauge detects that the pressure reaches 0.25MPa, switch the three-way valve and open the sludge discharge valve to discharge sludge for 60-80 seconds; ⑥ Close the sludge discharge valve and pressurize again; ⑦ Stop the backwash pump, close the backwash valve, and switch back to the purification mode.

[0019] The backwash pressure loop adopts PDWC physical deterministic control: sampling period of 200 milliseconds, control period of 200-5000 milliseconds. During the pressurization process, the drive energy is dynamically adjusted according to the energy compensation coefficient and inertia compensation is performed according to the momentum compensation coefficient. The pressure overshoot reaches the threshold of 0.25MPa, avoiding pressure overshoot and damage to the internal components of the main unit.

[0020] like Figure 3 As shown, the system implements a four-level interlock protection: Low level in the regulating tank → stops the main unit's booster pump, closes the inlet valve, and stops the #4 dosing pump; Low level in the clear water tank → prohibits backwashing to prevent the backwash pump from cavitating; Abnormal backwash pressure (exceeding the safety limit or failing to reach the threshold for an extended period) → alarm and shutdown; High level in the sludge tank → suspends sludge discharge. Protection events are timestamped and uploaded to the SuntransPlat cloud platform. Authorized mobile terminals allow maintenance personnel to remotely view the modal status, modify the purification cycle (default 30 minutes), sludge discharge duration (default 60-80 seconds), and pressure threshold (default 0.25 MPa). Local dual-modal switching control remains unaffected during network outages.

[0021] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention should still fall within the scope of the present invention.

Claims

1. A dual-mode intelligent switching control method for purification-backwashing in an OGEMS integrated wastewater purification host, characterized in that, The electric controller intelligent agent performs the following dual-mode switching control on the OGEMS host (10) and its supporting host inlet valve (11), host lift pump (12), dosing pump (13), host outlet valve (14), backwash pump (16), backwash valve (17), three-way valve (18), and sludge discharge valve (19): Purification mode: Open the host inlet valve (11), start the host lift pump (12) after a delay and start the dosing pump (13) in conjunction with it, open the host outlet valve (14), and the sewage flows into the clean water tank (15) after being purified by the OGEMS host (10). At the same time, the purification operation time is accumulated and timed. Switching trigger: When the purification operation time reaches the set cycle, the host lift pump (12) and dosing pump (13) are stopped in sequence, the host outlet valve (14) is closed and pressure is released after a delay, and the backwash mode is entered. Backwash mode: Open the backwash valve (17), start the backwash pump (16) to pressurize, when the backwash pressure detected by the electric contact pressure gauge (21) reaches the set threshold, switch the three-way valve (18) and open the sludge discharge valve (19) to discharge sludge for the set time, then close the sludge discharge valve (19) and pressurize again, after completion, stop the backwash pump (16), close the backwash valve (17), and automatically return to the purification mode; wherein, the dual-mode switching control is executed independently by the electric controller intelligent body locally, and the purification cycle, sludge discharge time and pressure threshold are adjustable online.

2. The method according to claim 1, characterized in that, The purification operation time is set to a cycle of 30 minutes and is adjustable online; the sludge discharge time is set to 60 to 80 seconds; and the backwash pressure threshold is set to 0.25 MPa.

3. The method according to claim 1, characterized in that, The execution sequence of the purification mode is as follows: open the main unit inlet valve (11) → delay for 5 seconds → start the main unit booster pump (12) → start the No. 4 dosing pump (13) in conjunction with the start of the main unit outlet valve (14) → accumulate running time → if the electromagnetic flowmeter detects that the outlet flow rate is normal, the purification continues.

4. The method according to claim 1, characterized in that, The method also includes interlock protection: when the regulating tank is at a low level, stop the main unit lift pump (12), close the main unit inlet valve (11) and stop the dosing pump (13); when the clear water tank (15) is at a low level, it is prohibited to enter the backwash mode; when the backwash pressure is abnormal, alarm and stop the machine; when the sludge tank (20) is at a high level, sludge discharge is suspended.

5. The method according to claim 1, characterized in that, The electric controller intelligent agent organizes the dual-mode switching as a state machine operation, and the state machine includes initialization, standby, water inlet boost, pH dosing, main unit purification, backwashing, drainage idle and fault alarm status. The host purification state and backwashing state switch bidirectionally according to the set cycle. The biochemical dissolved oxygen closed loop and sludge treatment closed loop states operate in parallel with the state machine and do not block each other.

6. The method according to claim 1, characterized in that, The electric controller intelligent agent uses AC zero-crossing switching to operate each valve and pump, completing the switching on and off at the instant the voltage crosses zero, thus eliminating switching arcs and inrush currents.

7. The method according to claim 1, characterized in that, The electric controller agent runs the PDWC physical deterministic AI control engine. The engine is based on the energy conservation and momentum conservation equations and solves the control output of the backwash pressure loop according to the control law u(t)=K1·Δt1+K2·Δt2+K3·Δt3. The sampling period of the backwash pressure loop is 200 milliseconds and the control period is 200 to 5000 milliseconds. The pressurization process has zero overshoot and reaches the set threshold.

8. The method according to claim 1, characterized in that, The mode, valve action, pressure and flow data of the entire dual-mode switching process are recorded by the electric controller and uploaded to the cloud management platform via Ethernet. It supports remote modification of the purification cycle, sludge discharge time and pressure threshold. The local dual-mode switching control is not affected during network outages.

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