Underground Structure of Mobile Toilets
The underground structures of mobile toilets vary significantly depending on their types, primarily falling into four categories: sewage-storage type, circulating-water flushing type, biodegradable type, and general-purpose type (connected to drainage pipes). Their designs are all centered around functional requirements and usage scenarios.
Sewage-Storage Mobile Toilets
The core of the underground structure for this type of toilet is the bottom tank, which is used to directly collect excrement without connecting to an external drainage system. The tank is typically made of high-strength plastic or metal to ensure airtightness and prevent leakage and odor diffusion. This design is suitable for short-term events (such as exhibitions and outdoor music festivals) or low-frequency usage scenarios (such as remote scenic spots). Its advantage lies in the elimination of the need for complex pipe networks, but regular cleaning of the tank contents is required to prevent overflow.
Circulating-Water Flushing Mobile Toilets
The underground structure of this type includes a small water tank and a circulating filtration system. The water tank stores flushing water, which is connected to the toilet bowl through pipes; the filtration system purifies the sewage to achieve water recycling. Some designs may involve a sewage discharge port for discharging filtered residues or sewage during regular maintenance. This type of toilet requires electricity to operate the filtration system and consumes only one-third of the water used by traditional toilets, making it suitable for scenarios with water scarcity but with access to electricity (such as temporary construction sites in cities).
Biodegradable Mobile Toilets
The underground structure of this type centers around a biological treatment module, which utilizes microorganisms to decompose organic matter in excrement into harmless substances (such as carbon dioxide and water). The module may include a stirring device to enhance decomposition efficiency or the addition of biological agents to accelerate the reaction. This type of toilet is highly environmentally friendly but requires regular replenishment of biological agents and cleaning of residues, resulting in higher maintenance costs. It is mostly used in ecologically sensitive areas (such as nature reserves) or long-term fixed locations (such as rural tourist spots).
General-Purpose Type (Connected to Drainage Pipes)
If a mobile toilet needs to be connected to an underground drainage system, its structure includes drainage pipes, odor-proof pipes, bottom gaskets, fixed angle irons, and mounting bolts. The drainage pipes are responsible for discharging sewage into the municipal sewer network; the odor-proof pipes use a U-shaped structure or a one-way valve design to block odor backflow; the bottom gaskets, made of rubber or silicone, ensure a leak-proof connection between the toilet bowl and the ground; the fixed angle irons and bolts are used to stabilize the position of the toilet bowl and prevent movement during use. The materials for underground components are mostly selected from PVC (lightweight, acid and alkali resistant), PP (heat-resistant, impact-resistant), or ABS (high strength, oil-resistant) to adapt to different environmental requirements.
