Wastewater Coagulation Flotation Separator for Solids Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Agricultural and industrial wastewaters require long retention times to remove suspended solids, nitrogen, and phosphorus compounds, limiting treatment volume and imposing economic burdens on farmers due to stringent environmental regulations, necessitating a method to reduce retention times and enhance waste management efficiency.
Innovation Solution
A method and system that adjusts the pH of wastewater to ensure at least 90% alkalinity is in bicarbonate form, using coagulants like aluminum sulfide or ferric sulfate to produce carbon dioxide, facilitating the separation of floatable solids and reducing contaminant concentrations through a dual separation process in a separator with a coagulant feed system and chemical control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional treatment methods are used to remove suspended solids, nitrogen, and phosphorus compounds, then treatment effectiveness is improved, but retention time increases to 1.5 hours, reducing treatment volume
Solution Approach 1:
The patent changes the chemical parameters of the wastewater by adjusting pH to specific ranges (6.3-10.3) and controlling alkalinity to ensure at least 90% is in bicarbonate form. This parameter optimization enables faster coagulation and separation processes, reducing retention time from 1.5 hours to 25 minutes while maintaining treatment effectiveness
Solution Approach 2:
The patent replaces traditional mechanical sedimentation processes with chemical coagulation followed by flotation. By adding coagulants that react to form carbon dioxide bubbles, the system uses gas-liquid flotation mechanisms instead of purely gravity-based sedimentation, dramatically reducing the time needed to separate solids from liquid
2Reliability
If coagulants are added to form carbon dioxide for flotation, then separation efficiency is improved, but system complexity increases due to pH control and chemical feed systems
Solution Approach 1:
The patent designs the treatment system so that the coagulant addition step serves multiple functions: it adjusts pH, generates carbon dioxide for flotation, and facilitates coagulation of suspended solids. This multi-functionality reduces the need for separate treatment stages and simplifies the overall system architecture
Solution Approach 2:
The system uses the wastewater's own alkalinity (at least 90% in bicarbonate form) to facilitate the coagulation reaction. The bicarbonate ions in the wastewater itself serve as a reactant, eliminating the need for external acid or base additions and simplifying chemical feed requirements
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 achieves a 99% reduction in suspended solids, 96% reduction in phosphorus, and 50% reduction in nitrogen concentrations, significantly reducing retention time to 25 minutes, allowing for higher treatment volumes while meeting regulatory standards and providing an economical solution for waste management.
Implementation Method 1
adding a coagulant to the wastewater to form at least carbon dioxide
Implementation Method 2
adding a coagulant to the wastewater to form at least carbon dioxide
Implementation Method 3
separating floatable solids buoyed up by the carbon dioxide from a clarified effluent in a separator
Implementation Method 4
adjusting a pH of the wastewater so that at least 90 percent of alkalinity of the wastewater is in the form of a bicarbonate ion
Data Source
AI summary
A method and system of treatment of agricultural and industrial wastewaters that contain high concentrations of suspended solids, nitrogen, and phosphorus compounds is disclosed. The method and system includes pre-treating the wastewater, controlling the amount of coagulants used, and controlling the mean velocity used for mixing, surface loading rate, and solids loading rate. The method and system functions as a sedimentation unit and gas flotation unit (solid/liquid separator). The pH of the effluent wastewater is stabilized within the separator by ensuring that there is sufficient alkalinity to buffer the wastewater. Sufficient gas is produced in the coagulation reactions to float and concentrate the solids, which results in as high as 99 percent reduction in suspended solids, a 96 percent reduction of the phosphorus concentration, and a 50 percent reduction of the nitrogen concentration in the effluent from the separator.