Frequently Asked Questions

Wastewater Solution


What is the dosing rate?

Dose is approximately two (2) pounds per million gallons per day (MGD) of influent flow rate. This is based on a typical municipal waste influent to the wastewater treatment plant (WWTP). Ultimately, dose is adjusted depending on plant loading and type of waste stream.

Where to dose?

For the best results, Aqua Assist must be applied at the point of optimum mixing between the influent and return activated sludge (RAS). Typically, a survey of the plant design layout will help determine the best product delivery point.

Bio React can be applied remotely upstream of a plant to attack Fats, Oil and Grease (FOG) buildup in pipes. Aqua Assist and Bio React can be used in drying beds and directly in digesters.

What changes to plant process control are needed to attain the best results?

Aqua Assist delivers microbes that greatly enhance solids reduction. An even higher level of solids reduction can also be obtained by increasing the sludge age. Although many WWTP can increase their Mixed Liquor Suspended Solids (MLSS) thereby increasing their sludge age, and enhancing solids reduction, they do not do so mostly because “older sludge” tends to have settling issues which can compromise effluent quality.

Drylet’s products enable improved settling at any sludge age, allowing facilities to operate at longer sludge ages and obtain solids reduction as high as 20%-50%.

Longer sludge ages can be obtained by cutting back on Waste Activated Sludge (WAS) rates. As WAS is reduced, the plant is controlled in a normal fashion – with RAS used to control blanket heights and to accommodate fluctuations in basins solids levels.

Will MLSS go up or down?

As the overall microbial activity in the aeration basin(s) increases, MLSS can track downward at first, if the same WAS rate is maintained. The final MLSS set point will be determined by identifying the greatest reduction of sludge that can be achieved while maintaining WAS levels that allow the maintenance of such MLSS levels.

What are changes to key performance indicators (“KPI”)?

Some KPIs that might change include parameters such as MLSS, WAS, RAS, SVI, Polymer use and chemical use for disinfection.

What visual changes should we expect to see, and in what time frame?

A clearer effluent can be observed, usually within 2-3 weeks. Also, the settling properties of the sludge will show a marked improvement within about 2-4 weeks. Sludge Settling tests will reveal a denser, better settling floc, lower settling volume and a clearer decant. In unmixed systems, basins will develop increased bubbling activity, which indicates a significant increase in off-gassing.

How much reduction can we expect?

The amount of sludge reduction is highly dependent on the influent composition, plant process control, aeration type, product application point and scheduled dosing of product. Reduction of sludge has been reported in the 20% to 50% range.

The use of polymer has been reported to decrease from 20%-50%.

Electrical savings and extended equipment life of presses and centrifuges will depend on the process, but are always significant.

Will it work in cold weather?

With surface aeration and very low water temperatures, the activity of all microbes is reduced – both native microbes and Aqua Assist or Bio React microbes. However, adding viable microbes will improve performance even at these low temperatures. WWTPs with blowers always deliver hot air, so that water temperatures are suitable even in the coldest climates.

What is the effect on cake quality?

The quality of the filter cake has been reported to be significantly better when compared to filter cake prior to the use of Aqua Assist. It has been observed that lower filter press runtime has been achieved with lower polymer use rates for cake pre-treatment.

Can we seed basins, or reseed a plant?

Aqua Assist is ideal for seeding a new plant, reseeding basins after washout or maintenance, as seen in this case study, and for combating depletion by toxins. And it is far less costly than trucking sludge from another facility.

Will it reduce ammonia?

Drylet has a separate product formulation that provides Nitrifiers for ammonia removal enhancement to the wastewater treatment process.

Will it reduce foam?

Aqua Assist and Bio React can reduce stagnant foam layers which inhibit off-gassing from basins.

Will it cause foaming?

No, the use of Drylet’s product does not lead to foaming. In fact, the microbes delivered by the product help eliminate foaming and bulking.

Will it change pH?

No. Aqua Assist and Bio React will not affect the plant’s pH.

Can we store it outside?

No. Aqua Assist and Bio React should be stored in a dry environment.

Where should we store it?

The product should be stored indoors away from heat, cold, and moisture in the original containers.

Any special handling instructions?

Drylet’s products are non-pathogenic, but breathing the dust should be avoided (see SDS).

Why do we have to keep applying it daily?

We recommend adding a small amount daily – about 2 Ibs per MGD, which amounts to just under 0.25 ppm. Some of the product is wasted with WAS daily. The daily dosage allows us to replace this wasted quantity. Also, native microbes enter through the influent every day. In the same way, Aqua Assist microbes must be added each day to maintain the beneficial balance that enhances solids reduction and ease of operations.

Will it kill our microbes?

Aqua Assist does not eliminate native microbes. Instead, a new biological balance is achieved at a higher rate of microbial activity than that attainable without Aqua Assist.

Will it reduce odor?

Yes, reduced odor has been reported throughout the plant operations. However, in order to reduce the odor of the influent Bio React will have to be applied in the collection system.

Will it consume fat?

Yes, Bio React is specifically formulated for the decomposition and breakdown of fats, oils and greases.