Beijing Mobile Toilet Fecal Treatment
The fecal treatment of mobile toilets in Beijing mainly adopts solid-liquid separation and microbial degradation, aerobic-anaerobic alternating fermentation systems, negative pressure collection technology, as well as other treatment methods such as fecal tank collection and water-free packaging.
Solid-Liquid Separation and Microbial Degradation: This technology first effectively separates the fibrous solids from the nitrogen-containing liquids in feces through centrifugation or pressure filtration. The separated solids can have their moisture content reduced to below 60% and then enter a drying chamber. Inside the drying chamber, thermophilic microorganisms (such as Bacillus subtilis) are used to decompose the solid portion. After approximately 72 hours of continuous fermentation, the fecal volume can be reduced to 20% to 30% of its original volume, while the moisture content is further reduced to below 40%. The final product can be used as a soil amendment for landscaping, achieving resource reuse. The liquid portion, on the other hand, is processed through a microbial degradation system, where organic matter is decomposed under aerobic or anaerobic conditions, with the process temperature controlled between 35-55 degrees Celsius, effectively preventing the generation of foul odors.
Aerobic-Anaerobic Alternating Fermentation System: After excreta enter the storage tank, solid-liquid separation is first carried out using a centrifugal separator. The liquid portion is then introduced into a small tank equipped with a suspended-filler biological reactor, where a biofilm composed of nitrifying and denitrifying bacteria is used for denitrification treatment. Through this series of biochemical reactions, the treated liquid water quality can meet the standard for toilet flushing water, achieving water resource recycling.
Negative Pressure Collection Technology: A closed piping system is designed inside the mobile toilet. When a user presses the flush button, a small vacuum pump is activated to generate negative pressure, causing feces and a small amount of flushing liquid to be rapidly sucked into the storage tank. The entire process is completed in a closed negative pressure environment, effectively reducing the probability of pathogenic microorganisms escaping with aerosols and improving toilet hygiene.
Other Treatment Methods: In addition to the above technologies, mobile toilets in Beijing also adopt other treatment methods such as fecal tank collection and water-free packaging. The fecal tank collection method involves collecting feces in a tank, which is then cleaned when full. The water-free packaging method uses degradable plastic bags placed at the bottom to collect waste, eliminating the need for water flushing and being more environmentally friendly and energy-efficient.
