Phosphate Processing System for Magnesium Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of phosphoric acid from low-grade phosphate rocks with high magnesium content is inefficient due to magnesium-induced issues like equipment fouling and low filtration rates, leading to yield losses and environmental hazards from contaminated pond water.
Innovation Solution
A phosphate processing system that integrates multiple processes to recover phosphoric acid from low-grade phosphate rocks, utilizing struvite production and recycling of pond water to maintain a negative water balance, reduce environmental impact, and produce magnesium-based fertilizers, thereby mitigating magnesium-related problems and enhancing yield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If low-grade phosphate rocks with high magnesium content are used for phosphoric acid production, then phosphate resource utilization is improved, but magnesium-induced equipment fouling and low filtration rates occur
Solution Approach 1:
The patent extracts and removes magnesium ions from the phosphate rock before processing through ion exchange resins or chemical precipitation methods. This extraction of the harmful magnesium component allows the subsequent phosphoric acid production to proceed without the fouling and filtration problems that would otherwise occur with high-magnesium low-grade rocks.
Solution Approach 2:
The patent introduces intermediary substances such as ion exchange resins, lime, or other chemical agents that mediate between the high-magnesium phosphate rock and the phosphoric acid production process. These intermediaries capture or neutralize magnesium ions, preventing them from causing equipment fouling and filtration issues while allowing the phosphoric acid production to continue efficiently.
2Quantity of substance
If conventional phosphoric acid production methods are used, then phosphoric acid is produced, but substantial phosphoric acid is lost in the filter cake
Solution Approach 1:
The patent changes the physical and chemical parameters of the filtration process, including using modified filter media with different surface properties, adjusting pH levels, and controlling particle size distribution. These parameter changes reduce the entrapment of phosphoric acid in the filter cake by modifying the interaction between the liquid phase and solid precipitate, thereby recovering more phosphoric acid product.
3Ease of manufacture
If pond water is discharged without treatment, then water treatment costs are reduced, but environmental hazards increase
Solution Approach 1:
The patent converts the harmful contaminated pond water into a beneficial resource by treating it to recover phosphoric acid and other valuable components. The treatment process transforms waste water containing pollutants into a usable product stream, simultaneously reducing environmental hazards and creating economic value from what would otherwise be a disposal cost.
4Reliability
If magnesium is removed from low-grade phosphate rocks before processing, then equipment fouling is reduced, but additional purification steps and costs are required
Solution Approach 1:
The patent merges the magnesium removal step with the existing phosphoric acid production process by integrating ion exchange or chemical precipitation operations into the flow sheet. Rather than adding a completely separate purification train, the magnesium removal is combined with other process operations, reducing overall process complexity while still achieving the goal of preventing equipment fouling.
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 recovers phosphoric acid from low-grade phosphate rocks, reduces water treatment costs, and minimizes environmental hazards by utilizing struvite production and recycling, achieving a more efficient and sustainable phosphoric acid production process.
Implementation Method 1
Phosphoric acid can be produced by a 'wet process' which involves reacting naturally occurring phosphate rocks with a mineral acid such as sulfuric, phosphoric acid or nitric acid.
Implementation Method 2
The phosphoric acid is typically separated from the insoluble gypsum precipitate by filtration.
Implementation Method 3
Another existing method is reverse osmosis. Reverse osmosis involves applying an external pressure that exceeds the osmotic pressure of the water component of an aqueous salt solution that is in contact with a semi-permeable membrane.
Implementation Method 4
One of such methods is known as double lime treatment. This method involves adding a calcium compound (e.g., CaCO3, Ca(OH)2 or CaO) to the pond water in two stages to precipitate phosphate and other impurities to produce purified water.
Data Source
AI summary
Embodiments described herein provide systems and methods for a phosphate processing system with integrated sub-systems, such as a phosphoric acid plant, precipitation system, crystallizer system, rinsing system, granulation system, pond water system, organics removal system, and/or exhaust treatment system. Such sub-systems can be integrated with each other by using one or more output streams from one or more sub-systems as one or more input streams for one or more sub-systems. In some embodiments, the phosphate processing system can produce phosphoric acid, struvite containing fertilizer, fertilizer using recycled struvite, magnesium or fluoride containing compositions using recycled magnesium or fluoride, and other components using phosphoric acid collected from a phosphoric acid and gypsum composition or using sludge collected from a waste stream, for example.