Septic Tank Phosphate Precipitation via Flow-Controlled Injection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Municipal wastewater treatment plants are ineffective in removing phosphates from septic systems, leading to eutrophication and water contamination in suburban and rural areas, as these systems directly leach untreated wastewater into the environment.
Innovation Solution
A water conditioning system that uses a phosphate precipitation solution, preferably hydrated aluminum sulphate, injected into the septic tank pipe based on measured water flow, to precipitate phosphates out of wastewater before it reaches the septic tank, forming salts that collect as solids.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If septic systems directly leach wastewater into the environment, then the system is simple and requires no external treatment equipment, but phosphates contaminate surface water causing eutrophication
Solution Approach 1:
The system performs preliminary phosphate removal by injecting precipitation solution into the wastewater stream before it reaches the septic tank. This pre-treatment action converts dissolved phosphates into precipitable salts, which then settle in the tank, preventing downstream eutrophication while maintaining system simplicity
Solution Approach 2:
The patent introduces an intermediary chemical substance (precipitation solution containing aluminum sulfate, ferric chloride, or lime) that mediates between the wastewater and the environment. This intermediary reacts with phosphates to form insoluble salts, effectively removing the harmful substance without requiring complex treatment infrastructure
2Object-affected harmful factors
If phosphate precipitation solution is injected into the septic tank pipe, then phosphate levels are reduced by up to 99%, but the system requires additional equipment and chemical injection infrastructure
Solution Approach 1:
The system utilizes the existing wastewater flow itself to drive the injection process. A flow meter monitors the wastewater stream and automatically controls the precipitation solution injection rate, eliminating the need for external control systems or complex dosing infrastructure. The system serves itself by using its own operational parameters to regulate treatment
Solution Approach 2:
The patent changes the chemical parameters of the wastewater by introducing precipitation chemicals that alter phosphate solubility. By adjusting chemical concentration and injection timing based on flow parameters, the system achieves high phosphate removal efficiency while keeping the physical infrastructure simple
3Object-affected harmful factors
If municipal wastewater treatment plants treat phosphates, then phosphates are removed before release, but homes connected to septic systems bypass this treatment infrastructure
Solution Approach 1:
The patent segments the wastewater treatment function from the centralized municipal system and implements it at the individual property level. By placing the precipitation injection system at the home's septic tank connection point, each property becomes an independent treatment unit, making the solution adaptable to both municipal and septic system configurations
Solution Approach 2:
The invention creates a universal treatment approach that can be applied to various wastewater systems including septic tanks, municipal connections, and alternative drainage systems. The precipitation chemistry and injection methodology remain the same regardless of the downstream destination, providing versatile phosphate removal across different infrastructure types
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
This system effectively reduces phosphate levels by up to 99% and fecal coliform by 95%, preventing eutrophication and extending the lifespan of septic systems without requiring external equipment or modifications.
Implementation Method 1
Phosphates are removed from wastewater by reacting the phosphates with other chemicals, such as calcium, iron, or aluminum, in order to create phosphate salts. The phosphate salts then precipitate out of the water and are collected and removed as sludge.
Implementation Method 2
An example of a phosphate precipitation reaction using hydrated aluminum sulphate is shown below: Al2(SO4)3+2PO4=2AlPO4+3SO4 The reaction creates aluminum phosphates (AlPO4), which collects at the bottom of a treatment plant as sludge.
Implementation Method 3
A flow meter is installed onto the water supply line of the building. The flow meter measures water flow into the building, which correlates to the volume of wastewater flowing out of the building.
Implementation Method 4
The phosphate precipitation solution is pumped into the pipe through the injection port at a rate that is controlled by the incoming water flow being measured by the flow meter.
Implementation Method 5
The phosphate precipitation solution mixes with the wastewater within the pipe to create treated effluent.
Implementation Method 6
The treated effluent flows into the septic tank where the phosphates form salts and collect as solids at the bottom of the septic tank.
Implementation Method 7
The treated effluent flows into the septic tank where the phosphates form salts and collect as solids at the bottom of the septic tank.
Data Source
AI summary
A water conditioning system for use in a building that produces wastewater that contains phosphates. The wastewater exits the building through a pipe that directs the wastewater directly to a septic tank. A phosphate precipitation solution is provided in a reservoir. A flow meter is installed that measures fresh water flowing into the building. Furthermore, an injection port is installed into the pipe before the septic tank. The phosphate precipitation solution is pumped into the pipe through the injection port at a rate that is controlled by the flow being measured by the flow meter. The phosphate precipitation solution mixes with the wastewater to create treated effluent. The treated effluent flows into the septic tank where the phosphates form salts and collect as solids.