Tibflux Ferrokill - Iron Removal from

Galvanising Flux Solution

Proven process to reduce ash and dross in galvanising operations

TIBFLUX FERROKILL is a double salt flux designed for iron removal from a galvanising flux solution without the need for ammonia and hydrogen peroxide additions. 

The normal operation of a flux solution is to periodically measure the density and pH of the solution, and add flux chemicals accordingly. If only basic double and triple salts are used then the addition of ammonia is also used to adjust the pH.  The TIBFLUX buffering system maintains the pH between 3.0 and 6.0 at all times, so there is no need for ammonia addition.

In either case, the ingress of iron from hydrochloric acid pickle solutions and their rinses always take place until equilibrium is reached. The Iron concentration in the galvanising flux tank will inevitably increase, and with it so does the production of ash and dross and the loss costly zinc.

The aim of all galvanizing plants is to maintain a flux of stable molecular ratio, stable pH and low iron concentration. This is not always achievable due to the type of work being processed. It may be reduced by good operator practice but not eliminated.

The most common method of iron removal in a galvanising flux tank is to treat the solution periodically (usually annually) with ammonia and hydrogen peroxide. Both of these chemicals bring with them inherent chemical hazards. Also the method has to be carefully controlled and as a rule of thumb only a 50 % reduction in the iron concentration usually results.

Alternatively the solution may be disposed of, and a new galvanising flux solution made up again.

TIBFLUX FERROKILL precipitates iron without the use of ammonia or hydrogen peroxide.

The FERROKILL system is designed to treat the galvanizing flux solution in a batch method.

A volume of flux is removed to an off line tank where TIBFLUX FERROKILL is added from a pre-made dosing tank.

Following agitation of the flux and TIBFLUX FERROKILL to provide complete mixing of the solution, the precipitated iron is filtered and the remainder of the treated flux is returned to the process flux tank.

The process is designed to treat approximately 4 batches per 24 hours and can operate automatically and thus a total of 28 batches of approximately 1000litres per batch (28,000litres) can be processed per week.

Process Benefits

• Potential Payback of less than a year

• Galvanizing flux operates with at a low iron concentration. Less than 5g/l.

• Iron removal from solution during production no down time for bath dump.

• Reduces ash, dross saves waste zinc.

• Potentially no further costs of disposal and make up of new galvanizing flux solutions

• Ease of control of pickle rinse and flux solution.

• 200kg drums that contain free flowing powder – NO caking.

• TIBFLUX FERROKILL may be operated hot or cold. (Hot is recommended).

• No hydrogen peroxide or ammonia additions to galvanizing flux tank to remove iron leading to a safer working environment

• Save on analysis costs, total solution analysis is only required every 3-4 months.

• TIBFLUX processes operate (recommended) ideally with 2 preceding rinses. It may operate with only one or even no rinse. In each process the excess acid is neutralised automatically and excess iron may be precipitated from solution.

Performance Data

 Galvanising flux chemistry

Waste produced

This page was last reviewed 27/01/09