Background
Alkaline and acid are usually used in petrol-chemicals, textiles, and metallurgy etc. Industry, and vice versa large amount of waste alkaline and acid liquid is produced finally. These waste waters contain not only a certain content of alkali and acid, but also various impurities such as solid particles, fibers, cellulose, gel, and soluble organic matter and inorganic ion etc. Directly discharging not only do great harm to environment but also waste a lot of valuable resource.
Traditional Treatment
As a usual, waste alkali and acid liquids are treated by neutralization, which is only to remove acid and alkali, but some impurities in these liquids can’t be taken out any more, what’s more, neutralization produces lots of inorganic salts, such as CaSO4, FeCl3 etc. These new produced salts become difficult to be reused and treated duo to many various impurities in it.
Therefor, simple neutralization can’t resolve all the problems of waste alkali and acid liquid disposal. Completely settling out these problems is to recycle and reuse these valuable resources in a closed system. But before reusing these liquids, impurities should be removed from these waste alkali and acid liquid.
After years of study and development, TANGENT developed a set of integrated CRM ceramic membrane technology to recycle wate alkali and acid liquid.
Case 1: Alkali Waste Recycling in Textile Printing & Dyeing Industry.
Fiber fabric should be socked, rinsed and cleared up before dyeing with hot alkali solution to remove natural fat, oil and wax, and hemicellulose. But large amount of waste alkali liquid produced therefrom. Traditional treatment way is to neutralizaiton and then discharged, or reused until hemicellulose content surpasses a certain content, and finally becomes waste alkali liquid disposal.
Case 2: Alkali Waste Recycling in Steel Industry
NaOH solution is used to clean the steel sheet by removing the grease.
In order to recycle these alkali waste, TANGENT takes CRM ceramic membrane as main filter to remove majority of impurities, and clear filtrate can be reused as alkali liquid of low content.
Process Diagram
Process Advantages
● Separating impurities from alkali liquid , filtrate to be recycled, both saving a lot of valuable alkali resource and reducing large amount of waste alkali liquid disposal
● NF can be integrated as further treatment way to recover hemicellulose or high purified alkali liquid
● Green separation process require no chemicals added, and no contamination produced therefrom
● Excellent chemical stability makes ceramic membrane suitable for treating such liquids
● Easy regenerated and maintenance, long service life make low running cost.
● Volume concentrate factor amount to 10，which reduces raw alkali liquid consumption 30%
If you need more details about ceramic membrane process for alkali effluent recycling ,please do not hesitate to contact with us or send email to us. We sincerely welcome your visit to our plant and reference projects.TANGENT is willing to communicate and share information with you on engineering process issues. We are looking forward to developing more market and more applications with your help, bring this new technology to end users, create more values and benefits for all parties.
