HMVT was contacted by a client who had problems with the treatment of chromium VI and arsenic in a waste water flow. The initial ideas involved the use of an ion exchanger resin to capture the heavy metals in the water. HMVT proposed to look at an alternative purification technique, based on chemical reduction and precipitation.
HMVT conducted six pilot tests in their test facility. Three different ion exchanger-resins were tested in three pilot tests. Purification techniques based on chemical reduction and precipitation were tested in the three other pilot tests.
The latter tests proved that the water could be treated with chemical reduction and precipitation approach. With a limited use of chemicals and limited sludge production, the requested discharge limit could be achieved. The technology also results in a significant cost reduction, compared to the techniques in which ion exchange resins are used.
The tests gave us and the client insight into amount of chemicals, reaction times, the amount and composition of the sludge formed in the process and the speed at which the sludge settles. With these parameters HMVT has made a design for a cost-effective full-scale water treatment.
Preliminary testing in the lab or with a pilot on site has the following advantages for you:
- You can try a new purification technique at low cost;
- Different techniques can be tested in the same, so you can make a better and result-based design choice;
- You have better insight for the full-scale implications of a technology: you gain prior insight into costs, energy consumption, waste flows released, treatment efficiency, chemicals- and carbon- consumption;
- Possible problems are known before the start of the full scale. This can be immediately incorporated into the design for the full-scale solution. This prevents unpleasant surprises afterwards.
- You get – in advance – a good insight into the return and costs of the techniques; this has major advantages in applying for permits and negotiating their terms.
Do you have a problem or question about water purification or air purification?. HMVT has all common air and water purification techniques available for you. Please feel free to contact our specialists.