Biodegradable Mobile Toilet

A biodegradable mobile toilet is an environmentally friendly public toilet that utilizes microbial decomposition technology to achieve harmless and resourceful treatment of excrement. It offers advantages such as water conservation, mobility, and pollution-free operation, making it widely applicable in scenic spots, alpine and water-scarce regions, and large-scale event venues.

Technical Principles and Classification

The core of a biodegradable mobile toilet is microbial community decomposition technology, which converts feces into carbon dioxide, water, and organic fertilizer through specific bacterial strains (such as marine microorganisms and anaerobic ammonium oxidation bacteria), achieving harmless treatment. Some models do not require water flushing and rely on microbial metabolism to eliminate odors. Based on technical characteristics, they can be classified into three categories:

1. Waterless Flush Types: Including waterless packaging types (directly collecting excrement), waterless biological treatment fertilizer production types (microbial decomposition for fertilizer production), and waterless flushable types (using a small amount of water for auxiliary cleaning);
2. Water-saving Types: Such as foam sealing types (using foam to cover excrement, with a water-saving rate exceeding 90%) and vacuum self-priming types (consuming only 0.5-1 liters of water per use);
3. Recirculating Water Flush Types: Achieving closed-loop water resource circulation through biological treatment or membrane separation technology to reduce external discharge.

Structural and Functional Characteristics

The main body of the toilet includes a fermentation degradation tank, exhaust pipe, forced ventilation device, and mechanical transmission device, with a PLC constant temperature and humidity control device regulating the fermentation environment (such as temperature and humidity). After mixing excrement with bacterial strains and carriers, it undergoes digestion and degradation, with达标 (up-to-standard) gas emissions. The daily power consumption is approximately 3-5 degrees (depending on the number of users). Some models are equipped with an intelligent temperature control system, operating at temperatures exceeding 60°C, which also provides sterilization and disinfection functions to ensure hygiene and safety.

Core Advantages

1. Water Conservation and Environmental Protection: No need for water supply and drainage pipes, with a water-saving rate exceeding 90% (foam sealing types) or extremely low water consumption per use (vacuum self-priming types), reducing water resource consumption;
2. Mobility: The toilet body adopts a steel frame cement composite structure or color steel plate, supporting overall mobility and adapting to temporary scenarios such as scenic spots and construction sites;
3. Pollution-free Treatment: With a degradation rate of 97%, it eliminates the need for excrement removal and transportation, converting feces into organic or liquid fertilizer for resource utilization;
4. Durability: The steel frame structure can withstand temperatures as low as minus 28°C, with a service life exceeding 20 years, reducing long-term maintenance costs.

Applications and Costs

The technology was deployed in 13 venues during the 2022 Beijing Winter Olympics, with the construction cost per toilet seat being 100,000 yuan lower than that of traditional water toilets. In Chengdu, carbon-neutral public toilets deployed in 2024 save over 3,000 tons of water annually. In terms of maintenance, the bacterial strain replacement cycle is 3-6 months, with a cost of approximately 300-500 yuan per toilet seat (varying between domestic and imported bacterial strains). The annual maintenance cost is about 15,000 yuan, with overall costs lower than those of traditional toilets.