Entering a sewage treatment plant is like stepping into a huge "urban intestinal hospital", where every inch and every piece of equipment is quietly busy purifying sewage. And the inspector, who is the "general practitioner" in this hospital, shuttles between the pipeline jungle and the machine matrix every day, using sharp eyes, keen sense of smell, and professional tools to conduct meticulous "physical examinations" for the entire system. Today, let's follow in the footsteps of the inspector and see what the sewage treatment plant inspects every day!
1、 Water inlet: the "first checkpoint" for sewage entering the plant
As soon as I walked into the factory area, I could hear the sound of water flowing from the inlet from afar. This is the "gate" for sewage entering the factory, and the inspector's gaze first locks on the grid machine - it is like a huge "iron comb", specially designed to intercept large debris such as plastic bags, tree branches, tissues, etc. in the sewage. If the comb gets stuck and debris piles up like a small mountain, the equipment will go on strike in minutes! The inspector not only needs to check whether the chain of the grid machine is loose and whether the rake teeth are deformed, but also needs to lie on the edge of the guardrail, use a flashlight to illuminate the water surface, and carefully inspect for any fish that have missed the net.
The sedimentation tank next to it is like a steady 'sediment catcher'. The inspector squatted down and gently stirred the water surface with a bamboo pole, observing the speed at which the sand particles sank. If strange eddies suddenly appear on the water surface, or sediment that should have settled "runs" onto the water surface, then we need to be alert: is the sand suction machine malfunctioning? Or is the water flow rate not right? At this point, the inspector must immediately take out their phone, take photos of the abnormal situation, and contact the repair technician.
2、 Biochemical processing area: a "super gym" for microorganisms
Passing through the buzzing blower room, we arrived at the core area of sewage treatment - the biochemical treatment zone. The aeration tank here is like a giant "microbial canteen", where billions of microorganisms "feast" and decompose pollutants in the sewage.
The inspector held a dissolved oxygen meter and carefully inserted the probe into the pool. 2.8mg/L, normal! ”He nodded with satisfaction. Dissolved oxygen is the "oxygen food" for microorganisms. If the value is too low, microorganisms will "go hungry" and the treatment effect will be greatly reduced; If it is too high, it will also waste energy. In addition to measuring data, the inspector will also look at the water surface like an art piece: fine and even small bubbles are normal, but if large bubbles suddenly appear, or a thick layer of white foam floats on the water surface, it is like microorganisms are "sounding the alarm" - water quality may be impacted, or there may be problems with the sludge!
The adjacent secondary sedimentation tank is the 'big stage' for separating mud and water. The inspector stood by the pool, staring closely at the outlet: clear and transparent water flow is the "top student". If there are scattered sludge in the water, it's like disharmonious debris suddenly appearing on the stage. You need to quickly adjust the speed of sludge reflux or check if the scraper is lazy.
3、 Medication room: a 'magic laboratory' for sewage purification
Pushing open the door to the dosing room, the smell of various medicines wafted in. This place is like a mysterious "magic laboratory", where PAC (polyaluminum chloride), PAM (polyacrylamide) and other chemicals are "magic powders" that make sewage clear.
The inspector stood on tiptoe and checked the liquid level gauge of the chemical storage tank: 'PAC is still one-third, it's time to replenish!'! ”He kept muttering while rapidly recording in his notebook. Then, he squatted down and checked the operation status of the dosing pump. These little guys are like precise "medicine couriers", once the measurement is inaccurate, adding too much or too little medicine will affect the effectiveness of sewage treatment. The inspector reached out and touched the pump body to feel if the temperature was normal; Listen carefully for any abnormal noise. If there is a leakage of chemicals at the pipeline joint, he will immediately transform into a "repair expert", wear gloves, tighten the valve, and clean up the leaked chemicals.
4、 Sludge Treatment Area: "Deformation Record" Factory for Sludge
The sludge generated by sewage treatment is like the "waste" in the "urban gut", but in the sludge treatment area, they will undergo a magical "transformation".
In the sludge concentration tank, the inspector poked the surface sludge layer with a bamboo pole and said, "The thickness is a bit high, we need to speed up the sludge discharge speed!" If the sludge accumulates here for too long, it will not only emit an unpleasant odor, but may also affect subsequent treatment. Further ahead, the sludge dewatering machine is running with a loud roar, squeezing the sludge into a mud cake. The inspector approached closely and carefully observed the moisture content of the mud cake: if the mud cake was soft, collapsed, and dripping with water, it indicated poor dewatering effect; If it is too dry and hard, it may be due to excessive pressure on the equipment. He would occasionally reach out and touch the filter cloth to check for any damage, like doing a 'skin check' on a machine.
The most nerve wracking thing is the biogas system! The inspector held a gas detector in hand, held his breath, and slowly moved around the biogas digester and biogas pipeline. If the instrument suddenly emits a sharp alarm sound, it means there is a biogas leak! You should know that biogas is flammable and explosive. Once exposed to an open flame, the consequences can be unimaginable. At this point, the inspector must remain calm, quickly close the relevant valves, evacuate personnel, and contact professional personnel for handling.
5、 Electrical equipment room: the "power heart" of the factory area
Entering the electrical equipment room, it feels like entering a 'steel forest', where equipment such as distribution cabinets, transformers, and motors are neatly arranged. This is the 'power heart' of the entire factory area. Once there is a problem, the entire factory will have to 'shut down'.
The inspector put on insulated gloves and carefully opened the distribution cabinet. The densely packed wires and switches inside were like jumping "musical notes" in his eyes. He scanned each wiring terminal with an infrared thermometer and said, '65 ℃, normal!' If a certain part of the temperature is too high, like a piercing noise on a musical score, it may be due to poor contact, and over time it may even cause a fire. He will also carefully inspect the outer skin of the wires for any signs of damage or burning, just like conducting a "full body medical examination" on the wires.
The backup generator in the corner is the "life-saving straw" of the factory area. The inspector will manually start the engine once a month, listen to the roar of the engine to see if it is normal, and check if the fuel level in the tank is sufficient. In case of a power outage, this generator should be immediately installed to ensure the continuous operation of the sewage treatment system.
6、 Environment and Safety: The 'Invisible Guardian' of the Factory Area
Don't think that inspections only focus on equipment, the environment and safety of the factory area are equally important for inspections! The inspector walked all the way, looking up to check whether there was rust or leakage in the high-altitude pipeline; Lower your head and check for any standing water or oil stains on the ground - these seemingly insignificant details can become safety hazards.
In the hazardous waste temporary storage room, inspectors carefully check the types and quantities of hazardous waste, and inspect whether the storage containers are sealed properly. If the packaging bag is found to be damaged or the label falls off, he will immediately replace it to prevent toxic and harmful substances from leaking and polluting the environment.
Even the green areas in the factory will not be overlooked by the inspectors! Before rainstorm in summer, he will check whether the drainage channel is unblocked; When the cold wave comes in winter, he will put on "warm clothes" for outdoor pipelines to prevent them from freezing and cracking.
The inspection work of sewage treatment plants is like an endless relay race, repeated every day without any carelessness. From the inlet to the outlet, from equipment to the environment, every corner and parameter is related to whether urban sewage can meet the discharge standards and whether our ecological environment can be clean and beautiful. Next time you pass by a sewage treatment plant, why not take a closer look - what's hidden inside is the perseverance and wisdom of countless inspectors guarding the clear waters and blue sky!
