Mobile Toilet Sewer Installation

When installing the sewer system for a mobile toilet, it is essential to focus on three core aspects: drainage and septic tank setup, pipe connection, and foundation fixation. Here are the specific operational points:

I. Drainage and Septic Tank Setup

1. Sewage Discharge Path Planning: Before installation, clarify the sewage flow direction and ensure that the drainage pipe has a slope of no less than 2% (i.e., a drop of 2 centimeters per meter) to allow sewage to naturally flow into the septic tank or municipal sewer network by gravity. Insufficient slope can lead to sewage retention, blockage, or odor backflow.
2. Septic Tank Capacity and Location: The septic tank capacity should be calculated based on the number of users. For example, each person generates approximately 0.1-0.2 cubic meters of sewage per day, so sufficient treatment space should be reserved. The tank should be located close to the toilet unit (generally no more than 10 meters away) but maintain a minimum safety distance of 3 meters to avoid affecting toilet use or polluting the surrounding environment during cleaning operations.
3. Odor Prevention Measures: A odor trap (such as an S-shaped or P-shaped water seal trap) must be installed at the connection between the drainage pipe and the septic tank. The water seal formed by the retained water blocks odor backflow. If connecting to the municipal network, ensure stable network pressure to prevent sewage backflow.

II. Pipe Connection

1. Sewage Pipe Connection: Connect the toilet sewage pipe to the nearest sewer or designated sewage collection tank, ensuring a pipe slope of ≥2%. Use dedicated sealing rings or hot-melt welding to secure the joints and prevent leakage. If connecting to a collection tank, reserve an inspection port for regular cleaning.
2. Pipe Material Selection: Prioritize PVC or HDPE pipes, which are corrosion-resistant, have a long lifespan, and have smooth inner walls that are less prone to blockage. Avoid using metal pipes, as they are prone to rust and perforation when exposed to sewage for extended periods.
3. Ventilation Design: If the septic tank is a closed structure, install a ventilation pipe at the top, with a height exceeding the toilet unit by at least 1 meter, to prevent methane gas accumulation and potential safety hazards.

III. Foundation Fixation

1. Unit Leveling: After hoisting the toilet unit to the designated location with a crane, use a spirit level to check the equipment's levelness, with a deviation of no more than 3mm, to avoid uneven structural stress or door frame deformation due to an uneven ground surface.
2. Fixation Methods:
   • Expansion Bolt Fixation: Pre-embed expansion bolts in the concrete foundation and securely fasten the toilet base to the bolts, suitable for areas with low wind speeds.
   • Counterweight Block Fixation: Place concrete counterweight blocks (each weighing ≥50kg) around the bottom of the toilet to increase self-weight and resist wind forces, suitable for coastal or windy areas.
3. Wind Resistance Reinforcement: In areas with strong winds, install ground anchor cables around the toilet or add more counterweight blocks to prevent equipment tipping due to strong winds.

After installation, conduct a water flow test to check for smooth drainage, joint leakage, and confirm normal septic tank liquid levels. Regularly clean the septic tank (generally every 3-6 months) to extend the system's lifespan.