Microbial Consortium for COD Reduction in Metal Working Fluids
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Solution Overview
Problem
Current biological methods for treating metal working fluids (MWFs) are inefficient in reducing chemical oxygen demand (COD) without prior processing, such as filtration or ultra-filtration, which adds time and expense.
Innovation Solution
A novel consortium of microorganisms comprising Rhizobium spp., Bacillus spp., and Pseudomonas spp., specifically Rhizobium radiobacter, Bacillus subtilis, Bacillus thuringiensis, Pseudomonas putida, and Pseudomonas stutzeri, which forms a biofilm capable of reducing COD levels in MWFs without pre-treatment, achieving a further 25% reduction compared to existing consortia.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If biological treatment methods are used without prior processing, then treatment cost and time are reduced, but COD reduction efficiency is insufficient
Solution Approach 1:
The patent combines multiple microorganism strains (Pseudomonas putida, Pseudomonas stutzeri, Rhizobium radiobacter, Bacillus subtilis, and Bacillus thuringiensis) into a consortium that works synergistically to degrade different components of MWF, achieving superior COD reduction (up to 90%) compared to individual strains or previous consortia, while eliminating the need for pre-treatment processes
Solution Approach 2:
The patent optimizes specific parameters including the ratio of microorganism strains in the consortium (e.g., Pseudomonas putida at 20-40%, Pseudomonas stutzeri at 20-40%), incubation temperature (25-37°C), pH (6.5-7.5), and aeration rates (0.5-2.0 vvm) to maximize COD reduction efficiency while maintaining system stability and reliability
2Reliability
If filtration or ultra-filtration is applied before biological treatment, then treatment reliability is improved, but processing time and expense increase
Solution Approach 1:
The microorganism consortium performs self-preparation by adapting to and colonizing the MWF waste stream directly, producing extracellular polymeric substances and biofilm structures that facilitate degradation without requiring external pre-treatment processes, thereby eliminating time and cost losses associated with filtration or ultra-filtration
Solution Approach 2:
The patent implements an acclimatization phase where the microorganism consortium is pre-adapted to the specific MWF composition before full-scale treatment, allowing the system to handle variable waste compositions effectively without requiring pre-filtration or pre-treatment steps
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 consortium effectively reduces COD levels in MWFs to 5000 mg/L or less in a shorter period, eliminating the need for initial processing and enhancing treatment efficiency and cost-effectiveness.
Implementation Method 1
micro-organisms are added to digest the unwanted constituents
Implementation Method 2
biological treatment of MWFs in which micro-organisms are added to digest the unwanted constituents
Data Source
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AI summary
There is described herein a consortium of micro-organisms comprising, consisting or consisting essentially of Rhizobium spp., Bacillus spp., and Pseudomonas spp.