Method and product for removal of chloramines, chlorine and ammonia from aquaculture water

Claim 2

A process for neutralising chloramines, chlorine and ammonia in water, which comprises adding to the water a bisulfite selected from sodium formaldehydebisulfite and potassium formaldehydebisulfite, or one or more materials which react to form the bisutfiteinsitu.

Claim 3

A process according to claim I, wherein the water contains pollutant selected from NH3, NH2CI, NHC1 2 , HOCI and OCI-ion, and the amount of the bisulfite is at least stoichiometric with respect to the pollutant.

Claim 4

A process according to claim 2, wherein the minimum amount of the bisulfite which is added to the water is 4 times the stoichiometric amount with respect to NH 3 , 12 times the stoichiometric amount with respect to NH2CI, 10 times the stoichiometric amount with respect to NHCl 2 or 12 times the stoichiometric amount with respect to HOCI and/or OCI- ion. 1

Claim 5

A process according to any preceding claim, wherein the pH of the water is at least 6.0, e.g. from 6.0 to 9.0.

Claim 6

A process according to any preceding claim, wherein the water is culture water substantially free from non-target oxidising pollutants, e.g. permanganates, peroxides, dichromates and arylmethane dyes.

Claim 7

A process according to any preceding claim, wherein the bisulfite is added to the water in combination with an inert material selected from diluents, carriers, excipients, lubricants, disintegrants and colourants.

Claim 8

A process according to claim 6, wherein any diluents or carriers are selected from salt, sodium sulfate, potassium chloride, starch, sugars, clays and calcium sulfate, wherein any excipients are selected from cellulose gum, povidone and starches, wherein any lubricants .are selected from calcium stearate, magnesium stearate, paraffin wax and stearic acid, wherein any disintegrants are selected from cross-linked povidone and sodium bicarbonate/citric acid, and wherein any colourants are selected from rose madder and acriflavin.

Claim 9

A process according to any preceding claim, which comprises adding to the water two aqueous solutions of, respectively, formaldehyde and sodium bisulfite.

Claim 10

A process according to claim 8, wherein the first aqueous solution contains at least 9% w/w formaldehyde.

Claim 11

A process according to claim 8 or claim 9, wherein the second aqueous solution contains at least 33% w/w sodium bisulfite.