Method for recovering purified sodium bicarbonate and ammonium sulfate
A technology of sodium bicarbonate and ammonium bicarbonate, used in chemical instruments and methods, carbonate preparations, ammonium sulfate, etc.
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0120] Determination of the optimal ammonium / sodium ratio in the sodium bicarbonate deposition step
[0121] The following examples illustrate how the complex phase equilibrium chemistry involved in the present invention can be used to determine the optimal ammonium / sodium ratio in the sodium bicarbonate deposition step. Knowledge of the chemistry illustrated in this example is required for all unit operations in this method.
[0122] The following equilibrium reaction equation represents the process in the sodium bicarbonate deposition step (using solid ammonium bicarbonate or carbon dioxide and ammonia):
[0123] Na 2 SO 4 +2NH 4 HCO 3 ←→2NaHCO 3 +(NH 4 ) 2 SO 4
[0124] Na 2 SO 4 +2NH 3 +2CO 2 +2H 2 O←→2NaHCO 3 +(NH 4 ) 2 SO 4
[0125] In order to understand the complexity of the phase equilibrium behavior described in this reaction, a schematic representation of the described system is required. The equilibrium salt pair quaternary system described by...
Embodiment 2
[0193] Illustrates the effect of lower sodium sulfate concentration on the formation of bicarbonate in the feed during the sodium bicarbonate preparation step The effect of the single-pass conversion of sodium
[0194] This example illustrates the negative impact of too much water in the sodium sulfate feed solution in the sodium bicarbonate production step on the per-pass conversion to sodium bicarbonate. with OLI TM Hysis, a process simulator coupled with properties TM Calculation.
[0195] As an example, Table 3 below shows the feedstock obtained from the sodium bicarbonate scrubbing of flue gas produced by burning coal.
[0196] This feed had a water concentration of 78.1% by weight and when mixed with 112.2 kg of anhydrous ammonium bicarbonate (ammonium / sodium molar ratio 1.10) and adjusted to 38°C, 47.0 kg of sodium bicarbonate was produced. The single-pass conversions of sodium and bicarbonate to sodium bicarbonate were 19.6% and 39.4%, respectively.
[0197] Ta...
Embodiment 3
[0202] Effect of Water Concentration on Salt Formation in Combined Salt Deposition Steps
[0203] This example illustrates the negative effect of water concentration on salt formation in a combined salt deposition step.
[0204] Figure 6 represents a Janecke diagram of the phase equilibrium at 0°C during the combined salt deposition step. If point A represents the charge fraction map of the feed, then it is obvious to those skilled in the art to ensure that the water concentration in the feed is adjusted such that the final mother liquor is at the Glauber's salt / ammonium bicarbonate / double salt constant equilibrium point (Point B) before it is reached, ie at point C "stops". On the other hand, on a one-way basis, double salts are generated in addition to combined salts. This means that the product (ammonium sulphate) starts to be recycled back to the sodium bicarbonate deposition step, reducing the overall efficiency of the process. As the process reaches a new equilibriu...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More