Solids Treatment System for Fecal Waste Volume Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for affordable and safe sanitation systems that can operate without sewer connections, particularly in regions where traditional sewage and wastewater treatment plants are expensive and impractical, and that can reduce water usage for waste transport, addressing health and environmental concerns.
Innovation Solution
A solids waste treatment system comprising a pasteurizer, mechanical dewatering press, and drying tunnel, which processes human waste to produce pathogen-free feces cakes with significantly reduced volume, suitable for combustion or safe disposal, and can be integrated into non-sewered toilet systems, optimizing water and energy efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional sewage and wastewater treatment plants are used, then pathogen treatment is effective, but the system is expensive and impractical for regions without sewer connections
Solution Approach 1:
The treatment system is divided into separate functional modules: a pasteurization unit for pathogen treatment, a dewatering press for solid-liquid separation, and a drying tunnel for moisture removal. This modular segmentation allows the system to be deployed in distributed locations without requiring centralized sewer infrastructure, while maintaining effective pathogen treatment through the pasteurization module.
Solution Approach 2:
The system processes waste on-site at the point of generation, eliminating the need for external sewer collection infrastructure. The integrated pasteurization-dewatering-drying sequence enables the system to treat and reduce waste volume autonomously, making it suitable for regions without centralized sewage systems.
2Reliability
If traditional sewage systems transport waste over long distances, then waste can be treated centrally, but water consumption for transport is excessive
Solution Approach 1:
The system extracts and removes the liquid phase from waste through the dewatering press and drying tunnel, separating it from the solid residue. This extraction eliminates the need for water-intensive transport of bulk waste, as only the essential solid fraction requiring treatment is processed on-site, while liquid can be handled separately or reused.
3Volume of moving object
If mechanical dewatering press is used to separate liquid phase, then volume reduction is achieved, but energy is consumed for compression
Solution Approach 1:
The pasteurization step is performed before dewatering, which softens and pre-treats the waste matrix, making subsequent mechanical compression more efficient. This preliminary thermal treatment reduces the energy required for the dewatering press by preparing the waste structure for easier separation, thereby reducing overall energy consumption while achieving volume reduction.
4Quantity of substance
If drying tunnel with forced air is used to dry feces cake, then moisture content is reduced, but energy consumption increases
Solution Approach 1:
The system employs a multi-stage approach where pasteurization temperature and dewatering pressure are optimized to produce a pre-concentrated cake with reduced moisture content before entering the drying tunnel. This parameter optimization in earlier stages reduces the moisture load that the drying tunnel must remove, thereby reducing the energy required for final drying while achieving the desired low moisture content in the output.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively reduces the volume of human waste by 80% or more, achieving pathogen reduction and meeting health and environmental safety standards, while minimizing water and energy consumption, making it suitable for deployment in both developing and developed nations.
Implementation Method 1
heat the slurry batch at an elevated temperature for a time period to produce a pathogen free slurry
Implementation Method 2
compress the pathogen free slurry to separate a liquid phase from a volume reduced solid waste
Implementation Method 3
the air duct system configured to propel forced air over the feces cake in the drying tunnel
Data Source
AI summary
System and method for volume reduction solids treatment for fecal waste are described. The system can include a pasteurizer (102) configured to receive a slurry batch and heat the slurry batch at an elevated temperature for a time period to produce a pathogen free slurry. The system can also include a mechanical dewatering press (104) configured to compress the pathogen free slurry to separate a liquid phase from a volume reduced solid waste. The volume reduced solid waste being formed into a feces cake. The system can also include a means to remove the liquid phase and a drying tunnel (106) comprising a conveyor housed and an air duct system. The air duct system configured to propel forced air over the feces cake.