The importance of washing for industrial by-product gypsum
There are plenty of impurities in the industrial by-product gypsum. The water-soluble impurities can be removed by washing and filtration. With regard to the washing filtration equipment, it’s the key factor to meet the requirement.
Meanwhile, the energy and water consumption and cake moisture are important factors also. The cake moisture will affect the following process and the costs involved.
Commonly used equipment for gypsum filtration
1. Belt filter press
Belt vacuum filter is vacuum negative pressure continuous production equipment with very high cake moisture and water consumption, and strict requirement for slurries. If the slurry concentration requirements are high. If the solid content in the slurry is low, the slurry will not be evenly and uniformly distributed, and the cake will be very thin, even the vacuum on the filter cloth will be damaged. Taking all the above problems into consideration, the washing and filtration efficiency cannot be achieved.
2. Centrifuge
At present, although the centrifuge for industrial by-product gypsum washing and separation can achieve continuous production, yet the unit capacity is too low.
Generally speaking, a group of centrifuges will be required to increase the capacity. In this case, the investment costs will be highly increased.
3. Air-flow washing filter press
Automation high efficiency washing filter press can process positive pressure filtration and countercurrent washing. Feeding from the external side can ensure evenly and uniformly distribution of pressure and cake. The cake moisture is very low with high production capacity which will help the customer save more energy and water. The energy and water consumption are 60% to 70% less than traditional filtration equipment. The washing efficiency can be up to 99%.
CJ Air-flow Washing Filter press
On the basis of long-term service to esteemed phosphorus chemical enterprises in Anhui, Hubei, Guizhou, Yunnan and other regions, CJ Filter has launched the CJW washing filter press with external side feeding, air-flow, complete and uniformly filter cake, anti-calcified, and effective countercurrent washing functions. The filter press not only ensures low cake moisture and high production capacity, but also finishes the washing and filtration all in one. The energy and water consumption are much lower than that of traditional filtration equipment. CJW can flexibly process the washing and filtration according to the material characteristics.
In the past two years, after much work and verification, CJ Filter has made breakthroughs in the comprehensive recovery of phosphorus gypsum and desulfurized gypsum. It's proven that the soluble phosphorus content in cake can be reduced to less than 0.1% after washing with 0.1-0.5 times water by CJW washing filter press. | |
The chlorideion residues in desulfurized gypsum can be reduced to less than 200ppm. To sum up the above benefits, CJW washing filter press will be great helpful for the comprehensive recovery of industrial by-product gypsum. |
Successful stories for CJW in industrial by-product gypsum application
Customer: | Located in Shanxi | |
Application: | Gypsum Neutralization Slags | |
Moisture: | 45% | |
Unit area: | 100m2 | |
Unit capacity: | 100t/d | |
The customer used to equip 4sets of 120m2 membrane filter presses to process the filtration. However, the cake moisture is high up to 86% with Water of crystallization in mushy style and cannot be piled up for storage. What's more, the storage yard is fully occupied. It greatly and badly affects the production. In 2017, the customer purchased one set of 100m2 CJAH air-flow high efficiency filter press to take the place of original membrane filter press. The cake moisture is greatly reduced, reaching to 45% with water of crystallization. The costs for delivery and storage are extremely reduced. In addition, the production capacity of one set CJAH is even beyond the total capacity of 4 sets of membranes. It garners the customer's loyalty. |
Customer: | Located in Guangxi | |
Application: | Titanium Gypsum | |
Moisture: | ≤17% | |
Unit area: | 712m2 | |
Unit capacity: | 280t/d | |
The cake moisture is 32% after filtration by membrane filter press. The cake has to be piled up for storage and naturally evaporated to less than 20% for sales. In this case, large area of storage yard is a must. Unfortunately, the production capacity is limited due to the small storage yard. Finally, the customer made technical reform and selected CJ filter press. The cake moisture is directly reduced to less than 17% for sales requirements. We help the customer save storage cost, greatly increase the capacity and make more profits. |
Customer: | Located in Yidu | |||
Application: | Phosphate acid slurry | |||
Moisture: | ≤12% | |||
Unit area: | 300m2 | |||
Unit capacity: | 900t/d | |||
It's contractor project for filter press and its auxiliary equipment to take the place of original two sets of belt filter press. The acid density is up to above 40% with a temperature of 80℃. The washing and filtration are finished all-in-one. Since the comprehensive recovery of gypsum is required, we use recycling phosphorus water in site for washing process. After washing, the soluble phosphate in cake is reduced to 5% which satisfactorily meet the requirement of 6.5%, with cycling time 30-35 minutes, a production capacity of 9-10 ton per hour. | ||||
Customer: | Located in Guangxi | |||
Application: | Washing Phosphorus Gypsum | |||
Moisture: | ≤12% | |||
Unit area: | 712m2 | |||
Unit capacity: | 600t/d | |||
The challenge is filtration of industrial by-product phosphorus gypsum and its storage. The phosphorus gypsum moisture is 18% after filtration by rotary filter press. CJ filter press will process the filtration of repulpable phosphorus gypsum. With a moisture of less than 12%, the cake is filtrated and purified with less content of impurities that perfectly meet the requirements for downstream production and comprehensive recovery. |
Customer: | Located in Yunnan | |
Application: | Thickened acid sludge | |
Moisture: | 15% | |
Unit area: | 512m2 | |
The customer originally used disk filter press in site for filtration process. However, the gypsum moisture is above 25% with total phosphate content over 10%, causing mass loss for phosphorus acid. After much work and verification, the customer made technical reform and selected CJ air-flow filter press to take the place. The cake moisture is 12% before washing. After washing, by 1times water, the moisture reaches to 15% with total phosphorus content less than 1%. It greatly increases the comprehensive recovery of phosphorus acid and economic efficiency. |
Customer: | Located in Hubei | |||
Application: | Desulfurized Gypsum | |||
Moisture: | <14% | |||
Unit area: | 290m2 | |||
Unit capacity: | 300t/d | |||
The customer used CJ air-flow filter press to process the filtration of desulfurized gypsum. The cake moisture is less than 14%. |