RoQuest® 4000

RoQuest 4000 contains a mixture of organic coagulants and iron (III) ions and is designed to be added upstream of multi-media and sand filters in the raw water flow of a RO system. This product enhances filtration performance by reducing turbidity and colour. The best results are obtained with raw water containing particles and organic dyes in relatively low concentrations or in which organic polymers have been under- or overdosed. The upper raw water limit for turbidity and colour is 2 NTU or 10 units for this product.

Dose RoQuest 4000 at least 5 m upstream of a multi-media filter. This ensures optimum mixing in the inlet upstream of the filter. Do not use static mixers, as the shear forces exerted by these devices may destroy the polymers contained in this solution.

Usually the dosage is between 2 and 25 ppm. Approximately 0.25 mg/l alkalinity (calcium carbonate) is required per mg/l RoQuest 4000. After addition of the coagulant, at least 25 ppm of residual alkalinity is required. A strong overdose of RoQuest 4000 may cause a deterioration in the quality of the filtered water. If you have any questions, please contact Avista Technologies for specific dosage instructions.

RoQuest 4000 should be added undiluted if possible. If dilution is necessary, do not dilute more than 4: 1 with RO permeate or demineralised water.

RoQuest 4000 is available in 23 kg canister, 230 kg drum  and 1100 kg IBC container.

Physical properties:
Appearance:   clear, amber-coloured liquid
Density:        1.3 – 1,4kg/litre
pH:               4,0 to 6,0

Technical properties
Produces feed water for RO plants in multi-media and sand filtration applications

  • compatible with thin film and cellulose acetate RO membranes.
  • Thanks to its properties as a filter aid, the penetration of solids is delayed.
  • good efficacy at low dosage
  • compatible with Vitec® Antiscaling 3000, 500


RoQuest® 4000