Highly Porous Slaked Lime Manufacturing Process
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing slaked lime struggle to produce highly porous products with high specific surface area and pore volume, which are critical for industrial applications like flue gas cleaning, due to limitations in controlling porosity and moisture content, leading to clogging and inefficiencies.
Innovation Solution
A process involving a controlled water/quicklime ratio of 0.8 to 1.3 and efficient vapor removal along the slaking zone in a single or multi-stage hydrator, using a bag house filter to minimize steam-lime contact, results in a highly porous slaked lime with a specific surface area between 30 to 48 m^2/g and pore volume of 0.15 to 0.3 cm^3/g, ensuring reproducibility and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional slaking methods are used, then standard slaked lime is produced, but high porosity and specific surface area cannot be achieved
Solution Approach 1:
The invention changes key process parameters including water-to-lime ratio (0.8-1.3), slaking zone temperature (90-110°C), and residence time (5-15 minutes) to achieve high porosity (0.2-0.4 cm³/g) and specific surface area (30-50 m²/g) while maintaining industrial feasibility
Solution Approach 2:
The invention extracts steam continuously from the slaking zone using a steam removal device, preventing steam from contacting the slaked lime product. This extraction of the harmful steam phase enables high porosity formation without the clogging problems of conventional methods
2Manufacturing precision
If high porosity is achieved through new methods, then specific surface area increases, but process complexity and equipment requirements increase
Solution Approach 1:
The hydrator device performs multiple functions simultaneously: slaking of quicklime, steam generation, steam removal, and product cooling in a single integrated unit. This multi-functionality achieves high specific surface area (30-50 m²/g) without requiring separate complex equipment for each function
Solution Approach 2:
The invention introduces an intermediary steam removal system that acts as a mediator between the slaking reaction zone and the product collection zone, allowing high porosity formation while preventing steam-related clogging and equipment complexity
3Productivity
If vapor is not removed during slaking, then equipment is simpler, but clogging occurs and productivity decreases
Solution Approach 1:
The steam removal device operates continuously throughout the slaking process, maintaining constant steam extraction from the slaking zone. This continuous action prevents clogging and maintains high productivity (0.2-0.4 cm³/g pore volume) without requiring intermittent complex interventions
Solution Approach 2:
The invention converts the harmful steam byproduct into a beneficial continuous removal process that prevents clogging. The steam generation from the exothermic slaking reaction is harnessed and continuously extracted, turning a source of problems into a controlled feature that enhances productivity
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 process achieves highly reproducible and stable high-specific-surface-area and high-pore-volume slaked lime, reducing clogging and improving sorbent performance, while being industrially feasible and sustainable over time.
Implementation Method 1
Calcium oxide from the quicklime reacts quickly with water to form calcium di-hydroxide Ca(OH)2, under the form of slaked lime or hydrated lime, in a reaction called hydration or slaking reaction which is very exothermic
Implementation Method 2
efficient vapor removal along the slaking zone in a single or multi-stage hydrator, using a bag house filter to minimize steam-lime contact
Implementation Method 3
results in a highly porous slaked lime with a specific surface area between 30 to 48 m^2/g and pore volume of 0.15 to 0.3 cm^3/g
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Process for manufacturing highly porous slaked lime comprising a feeding step of quicklime, a feeding step of water in a feeding zone of a hydrator, a slaking step of said quicklime in a slaking zone of said hydrator and a maturation step in a maturation zone of said hydrator to form slaked lime.