FAQs
Useful information about the Aquatherm Products
Q1. We already have too much hot water, using flash steam and condensate to pre – heat process water — how can Aquatherm help?
Pre-heating water with flash steam or condensate may be thought of as ‘saving energy’ but in fact it is simply moving the waste from one area to another, as the ‘saved heat’ ends up down the drain after the washing process. When process water is heated in this way, the ability to recover the heat from the waste water and use it to heat the process water disappears as it is already heated and there is nowhere for the saved energy to go!
The solution is to return the condensate and flash to the boiler and to use the waste water heat to provide the energy for washing. This will already have been dismissed by many plants as the boiler feed pumps may already be working at their maximum temperature – but there are a number of solutions. This is a subject in itself , but as every case is different, please consult us and we will be pleased to advise. But do not use flash steam or condensate to heat process water thinking that you are making the best use of your energy!
Q2. We have been guided by our chemical suppliers to use ‘low temperature chemistry’, which we are told will reduce our energy consumption. What is the point of installing Aquatherm then?
To get the best results from ‘low temperature washing’ in a CBW – which can be anything between 40 and 60 C – the water supply to the machine is heated to provide a hot rinse. As a result, the waste water temperature will actually be higher than with a normal process where only the wash section is heated. For the low temperature process to deliver savings in energy it is essential to recover and reuse the heat from the waste water.
Q3. Some of our processes require prewash temperatures below 40C to prevent stain setting - surely that means we cannot use Aquatherm?
There is a setting in the Aquatherm control system to deal with this. Simply set the ‘not to exceed temperature’ to (say) 40C and the system will only extract the energy from the waste water that is needed to attain this temperature.
Q4. We process a lot of dust mats and engineer’s overalls - the waste water is very dirty and contaminated. Won’t this result in the Aquatherm blocking up?
The Aquatherm system self cleans automatically every 30 minutes for 30 seconds by default. Simply change the settings to clean more frequently and the system will remain ‘as clean new’ for life.
Q5. How do we know that we are making the savings promised?
Every second the temperatures and flows are recorded, and displayed on the screen. Also on display at all times is a record of the kWh being saved and the value since the system was first started.
Q6. What happens if only one of our 3 tunnel washers is being used?
Aquatherm measures the flow of fresh water and automatically adjusts the volume of waste water being pumped to match the fresh water and optimise the energy saving, regardless of how many machines are in use.
Q7. Will the Aquatherm be capable of handling the volume of water when we expand the plant?
The range of Aquatherm models covers flow rates between 3 and 35 cubic metres per hour. Select a model which will deal with the maximum flow that you anticipate in the future, and it will automatically run at a reduced level.
Q8. Is it possible to monitor and control pH?
An option exists to measure the pH of the waste water before and after the Aquatherm. As the flow rate of the waste water is measured, a dosing pump injects a calculated volume of acid which is mixed by the highly turbulent flow inside the Aquatherm. The pH exiting the unit is recorded and used to adjust the dosing level if needed.
Q9. There is a provision for ‘chemical cleaning’ built into Aquatherm. How often is this needed?
In the great majority of installations, chemical cleaning is never needed. However if the fresh water is unsoftened, a thin layer of lime scale may build up on the fresh water surfaces, which over a period of time will reduce the heat transfer. In such cases the unit should be cleaned with a diluted acid when it is evident that performance has reduced.
Q10. How do we establish which Aquatherm installation is best for us, what it costs and most importantly what is the payback?
The financial viability can be established by running a simulation based on data provided by completing a questionnaire (see Contact page). Once the decision has been made to proceed, a full site survey will be carried out resulting in a detailed installation plan tailored to the specific site.
Q11. Aquatherm is a heat recovery system, yet claims to save water, electricity and chemicals too. How does that work?
With the requirement for steam to heat the process water reduced by up to 80%, less feed water is needed by the boiler. Reducing the drying time means that the dryers operate for shorter periods, saving electricity and wear and tear. Finally, the ability to raise wash temperatures without the cost normally involved can permit reducing the chemical consumption needed to achieve the desired quality, or allow the use of cheaper formulations.
Q12. How much does it cost to run an Aquatherm system?
Just the electrical cost to run a 1. 1 or 2.2 kW motor, depending on model.
Q13. How long can we expect an Aquatherm system to last?
The heart of an Aquatherm system – the main heat exchanger – will run for a generation. Moving parts such as pumps and valves may need repair or replacement as with any piece of production equipment.
Q14. We are planning to convert to ‘Steam less’ operation. How relevant is Aquatherm to a hot water solution?
It is ideally suited to steam free designs. With up to 80% of the heating being provided from waste heat, the capacity and energy consumption of a hot water boiler is significantly reduced.