Fluidized Bed Crystallizer Reflux Inlet Height Control

Solution Overview

Problem

Existing fluidized bed crystallization technologies face challenges in synchronously achieving efficient crystal product recovery and controlling product granularity, leading to increased operational costs and complexity due to the need for additional sedimentation facilities and complex internal circulation designs.

Innovation Solution

A sewage treatment device with a fluidized bed body, reflux device, and chemical feeding device is introduced, featuring a sedimentation zone, transition zone, and fluidization zone, where the reflux inlet's height is adjustable to control crystal product granularity, and the reflux pump aids in microcrystal aggregation, eliminating the need for additional sedimentation tanks by optimizing crystal nucleation and growth within the fluidized bed.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a sedimentation tank or solid-liquid separator is added after the fluidized bed to intercept microcrystals, then the effluent quality is improved, but the treatment process is prolonged and the occupied area is increased

Engineering Contradiction:

Improveeffluent qualityVSAvoidtreatment process duration

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The invention merges the sedimentation function with the crystallization reactor by dividing the reactor into three zones: fluidization zone for crystal growth, transition zone for flow transition, and sedimentation zone for microcrystal interception. This integration eliminates the need for separate sedimentation tanks, thereby shortening the treatment process and reducing occupied area while maintaining effluent quality.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The crystallization reactor is segmented into three functional zones along the vertical direction: the fluidization zone at the bottom for crystal growth, the transition zone in the middle for flow transition, and the sedimentation zone at the top for microcrystal interception. This segmentation allows each zone to perform its specific function efficiently within a single reactor.

Inventive Principle:

Principle #1Segmentation

2Reliability

If a sedimentation tank or solid-liquid separator is added after the fluidized bed to intercept microcrystals, then the effluent quality is improved, but the operation and maintenance costs are increased

Engineering Contradiction:

Improveeffluent qualityVSAvoidoperation and maintenance costs

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The invention merges the sedimentation function with the crystallization reactor by dividing the reactor into three zones: fluidization zone for crystal growth, transition zone for flow transition, and sedimentation zone for microcrystal interception. This integration eliminates the need for separate sedimentation tanks, thereby shortening the treatment process and reducing occupied area while maintaining effluent quality.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The fluidized bed system performs self-sedimentation through its internal structure. The sedimentation zone within the reactor automatically intercepts microcrystals from the effluent, and the collected microcrystals can be reused as seed crystals, reducing the need for external treatment facilities and lowering operation and maintenance costs.

Inventive Principle:

Principle #25Self-service

3Loss of substance

If internal circulation equipment is added to the crystallization reactor to intercept microcrystals, then the microcrystal loss is avoided, but the design becomes complex and the operation management difficulty increases

Engineering Contradiction:

Improvemicrocrystal lossVSAvoiddesign complexity

Core Design Contradiction:

Loss of substanceVSDevice complexity

Solution Approach 1:

The invention merges the sedimentation function with the crystallization reactor by dividing the reactor into three zones: fluidization zone for crystal growth, transition zone for flow transition, and sedimentation zone for microcrystal interception. This integration eliminates the need for separate sedimentation tanks, thereby shortening the treatment process and reducing occupied area while maintaining effluent quality.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The fluidized bed system performs self-sedimentation through its internal structure. The sedimentation zone within the reactor automatically intercepts microcrystals from the effluent, and the collected microcrystals can be reused as seed crystals, reducing the need for external treatment facilities and lowering operation and maintenance costs.

Inventive Principle:

Principle #25Self-service

4Loss of substance

If internal circulation equipment is added to the crystallization reactor to intercept microcrystals, then the microcrystal loss is avoided, but the operation management difficulty increases

Engineering Contradiction:

Improvemicrocrystal lossVSAvoidoperation management difficulty

Core Design Contradiction:

Loss of substanceVSEase of operation

Solution Approach 1:

The invention merges the sedimentation function with the crystallization reactor by dividing the reactor into three zones: fluidization zone for crystal growth, transition zone for flow transition, and sedimentation zone for microcrystal interception. This integration eliminates the need for separate sedimentation tanks, thereby shortening the treatment process and reducing occupied area while maintaining effluent quality.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The fluidized bed system performs self-sedimentation through its internal structure. The sedimentation zone within the reactor automatically intercepts microcrystals from the effluent, and the collected microcrystals can be reused as seed crystals, reducing the need for external treatment facilities and lowering operation and maintenance costs.

Inventive Principle:

Principle #25Self-service

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 solution enables simultaneous improvement in crystal product recovery rate and control over product granularity, reducing operational complexity and costs by allowing for full-amount product interception within the fluidized bed, with the reflux device being easily integratable into existing systems without structural changes.

Implementation Method 1

Fluidized bed crystallization is a common technology for wastewater treatment and recycling

Methodology Applied

Scientific EffectFluidization: Fluidisation

Implementation Method 2

a sedimentation tank or a solid-liquid separator is usually additionally adopted after the fluidized bed to improve the interception of the microcrystals

Methodology Applied

Scientific EffectSedimentation: Sedimentation

Implementation Method 3

Fluidized bed crystallization is a common technology for wastewater treatment and recycling

Methodology Applied

Scientific EffectCrystallization: Crystallisation

Data Source

PatentUS11629077B2Sewage treatment device capable of controlling product crystallization granularity and sewage treatment method

Publication Date: 2023.04.18 INST OF URBAN ENVIRONMENT CHINESE ACAD OF SCI

AI summary

A sewage treatment device includes a fluidized bed body, a reflux device and a chemical feeding device. The fluidized bed body is sequentially provided with a sedimentation zone, a transition zone and a fluidization zone from top to bottom. The reflux device is connected to the fluidized bed body through a reflux pipe. The reflux pipe extends into the fluidized bed body from the sedimentation zone, and the granularity of a crystal product can be controlled by changing the height of a reflux inlet at the bottom end of the reflux pipe in the fluidized bed body. By controlling the position of the reflux inlet of the reflux pipe in the fluidized bed body, combining product granularity requirements, and adjusting an insertion depth of the reflux pipe, the granularity of a final product can be flexibly regulated and controlled, and meanwhile, a product recovery rate is improved.