Root analysis of biogas leakage and sewage tank odor in the basement of the old building
When you walk into many old commercial buildings, shopping malls or mixed residential and office buildings in the greater Taipei area, there is often a lingering pungent stench in the basement or parking lot. This smell is not only a severe olfactory pollution, but also contains corrosive and toxic "hydrogen sulfide (H2S)" and flammable "methane (CH4, biogas)". The root cause of odor and methane leakage is usually the lack of proper maintenance of the "underground sewage tanks and septic tanks" on the third or fourth floor underground for many years, or the aging and cracking of the tank's sealing cover. In a closed anoxic environment, organic matter in domestic sewage is decomposed by anaerobic bacteria to produce a large amount of acidic biogas. These gases will not only flow back into offices on the first floor or even high floors through drainage pipes, but will also combine with water vapor in the air to form dilute sulfuric acid, which will violently corrode weak wire troughs, iron pipes and electromechanical control boxes in the basement. It is an invisible killer in commercial property management.
Electromechanical protection and dual-circuit switching configuration of sewage pumps that are frequently burned due to debris
Underground sewage tanks must rely on "Sump Pumps" to pump wastewater up to the municipal sewer. However, sewage pumps in old buildings often burn out due to the following reasons, causing water in the basement to flood the computer room:
1. Due to the large number of tenants in commercial buildings, paper towels, rags, and plastic bags are often thrown into the toilet. After entering the sewage pool, these debris will become entangled in the impeller of the drainage pump, causing the motor to become stuck and overloaded, and the coil will overheat and burn out within a few minutes.
2. The heavy-weight float switch (Float Switch) that controls the opening and closing of the drainage pump is prone to losing its buoyancy and getting stuck in the "on" position when covered with oil and dirt for many years. This will cause the sewage pump to continue to "idle without water" after the pool water is drained, and the motor will quickly burn out due to lack of water flow to dissipate heat.
In order to solve this pain point, modern electromechanical engineering always adopts a configuration: install two mutually backup sewage pumps in the pool (a crushing sewage pump equipped with a serrated shearing blade, which can chop fiber debris). The control box uses PLC or alternating relay, which automatically starts pump A or pump B in turn every time the water level rises. When one of the pumps fails or the water level exceeds the warning line, the system automatically starts the other pump and sounds an alarm to ensure that the drainage system is not interrupted for 24 hours.
Underground sewage pool aeration mixing system and activated carbon filter upgrade method
To completely eradicate the stench in the basement, pumping water and fertilizer alone is not enough. The "aerobic aeration mixing and activated carbon filtration system" renovation method must be introduced:
* Lay a multi-hole stainless steel aeration pipe or an anti-clogging bubble diffuser (Diffuser) at the bottom of the underground sewage tank, and fresh air is continuously injected from the annular blower in the ground machine room. Convert anaerobic environment into "Aerobic Environment", inhibit anaerobic bacteria from producing hydrogen sulfide odorous gas, and prevent sludge from solidifying and depositing on the bottom of the tank through bubble stirring.
*Replace the maintenance manhole cover on the roof of the sewage pool with an airtight explosion-proof cover, and set up an independent exhaust pipe connected to the "Stainless Steel Activated Carbon Odor Filter (Carbon Odor Filter)". The high porosity physical adsorption capacity of activated carbon is used to completely filter out the trace amounts of hydrogen sulfide and volatile organic compounds spilled in the pool, and then discharged to the outdoors on the top floor of the building using an exhaust fan to ensure that the air in the basement is fresh and odor-free.
提升商办与住宅大楼环境品质以增加物业租售价值的关键
From the perspective of business assets and CapEx financial amortization, the return on mechanical and electrical renovation of the sewage and septic system in the basement of the old commercial office building is huge.
The stench in the basement and frequent sewage pump failures will directly lower the "visual and olfactory grade" of the building, causing the building's rent to be greatly reduced, and even being reported and fined by the Environmental Protection Bureau.将污水池升级为自动粉碎双泵系统、加装曝气搅拌与活性碳除臭，工程费用通常在 15 万至 30 万元之间。 This investment can eliminate the odor in the basement environment, avoid millions of maintenance fees caused by methane corrosion of mechanical and electrical lines, and improve tenants' satisfaction with property management, thus maintaining high rental yields. For real estate businessmen acquiring old commercial offices, solving this "invisible stench symptom" is a classic value-add operation technique to increase the property's assessed value at a low cost.
🇹🇼 Expat Living Note: Home Repairs in Taiwan
If you are an international resident renting an apartment in Taipei, New Taipei, or anywhere in Taiwan:
- Voltage & Electrical Safety: Taiwan standard household voltage is 110V (60Hz). Do not plug 220V imported European/UK appliances directly without a certified step-up transformer.
- Plumbing Terminology: Local plumbers are called 水電 (Shuǐdiàn) and handle both water and electrical repairs.
- Landlord Obligations: Under Article 429 of Taiwan Civil Code, landlords are legally responsible for repairing natural wear and tear (such as hidden wall pipe leaks, water heater faults, or booster pump failures) unless explicitly waived in your lease.
Legal Disclaimer
The information provided on this website is for general educational and reference purposes only. For hazardous repairs involving live 220V electrical circuits, main gas lines, or structural wall drilling, always consult certified, licensed technicians. SOSfix disclaims any liability for personal injury or property damage resulting from DIY repair attempts.
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