However, the first test results with this setup are actually too good. The control is too stable: a slurry flow rate stability of ±0.2% is obtained. At the downside of this, the response time to achieve control is too long. It takes over one minute to reach stability, and that is a waste of expensive slurry. To solve this issue, the size of the control orifices of the pressure controller is changed from 0.2 mm to 0.5 mm. Now the control is better than ±1%, with a sufficiently fast response time.
The operators are very satisfied with this solution. They do not have to constantly watch and manually adjust the flow rate, and the stability of the slurry flow delivery is far better than they ever achieved manually, and with very little wasted slurry. Moreover, they now have data acquisition and computer control of this part of the process.
This solution has not happened because of ‘just one Bronkhorst product’, but due to a long-term relationship with the client, which evolved and developed over 2-3 years - giving them what they need using Bronkhorst products.