The Answer for Potable Water Clarification.
Aluminum has long been used as a primary coagulant to clarify water for drinking and industrial process uses. Historically, the main delivery mechanism for Aluminum ions came in the form of
Aluminum Sulfate (Alum). The main reasons alum was so widely used was availability and lack of low-cost alternatives. However, there are other costs and problems associated with the use of alum. Alum is extremely
acidic and can dramatically drop pH even when used at normal dosages. This creates the need to feed additional chemicals (lime or caustic soda) to compensate for the decline in pH. The use of Alum also produces relatively large
amounts of aluminum hydroxide sludge. Therefore, when considering the whole picture, the cost of using Alum also includes:
- Pre and Post pH Adjustment (lime, caustic, etc.)
- Sludge Treatment (flocculation / dewatering)
- Solids Disposal
Increased sludge handling costs, pH adjustments and regulations requiring higher finished water quality are responsible for driving the development of more cost-effective and efficient coagulants.
Polyaluminum Chloride (PAC)
compounds were developed to provide better performance than alum could offer. While they accomplished this goal, they also provide additional cost benefits when compared to alum. PAC has a minimal impact on pH and therefore minimized the need to feed adjustment chemicals. And it is able to do a better job while using 30-60% less aluminum on average. This translates roughly to a similar percent reduction in the amount of sludge produced.
The growth rate of PAC has been very impressive. In many areas where PAC has been marketed for a reasonable time period it has replaced over 75% of the total alum demand. Around the same time the
PAC was developed, organic polymers, which aided the coagulation process, were also introduced to the water treatment industry. These polymers were generally not effective as primary coagulants but when used in conjunction with
aluminum, helped to improve overall performance.
Recently, the advance to a third generation of treatment products combines the benefits of PAC and Organic Coagulants into an optimal treatment approach. Our QEMIPAC
compounds provide the highest level of performance and reduce overall treatment costs while minimizing the associated costs of pH adjustment and sludge disposal. Furthermore, QEMIPAC products will result in streamlined operations, as the need to feed other supporting chemicals will be eliminated.
Depending on water chemistry and process specifications, specific blend types can be formulated to meet the demands of high quality water production and reduce overall treatment
cost. Please contact us for more information, pricing and /or samples of these innovative products.