Crystallization

NiTech crystallizers are suitable for anti-solvent and cooling crystallization processes.

In terms of cooling crystallization, the technology offers the simultaneous control of scale-independent mixing and temperature distribution that cannot be achieved in traditional batch crystallizers. In terms of anti-solvent crystallization, NiTech crystallizers provide intensive mixing at the point of contact between solvent and anti-solvent, suspending crystal particles evenly along the crystallizers and leading to narrow crystal size distributions. NiTech crystallizers are, however, not suitable for evaporation crystallization.

Crystallization is a key application. It impacts all aspects of manufacturing processes, and is currently regarded as a ‘problem area’ by many companies.

A successful Proof of Technology with AstraZeneca (AZ) confirmed a 97% reduction in crystallization time, from 9 hours 40 minutes down to 12 minutes. This documented a 50% reduction in capital cost and major savings in operating cost. In addition, AZ noted significant qualitative benefits as it ‘responds in a predictable manner’.

The NiTech Crystallizer

Crystallization typically involves forming a solid from within a liquid. Often it involves either a cooling or a drowning-out process. The formation of ice from water is the most common example for the former.

Crystallization is traditionally done in batch vessels or via a series of tanks. These make it difficult to control key factors such as crystal size and shape due to the reduced specific area for heat transfer and inconsistent mixing conditions. This is also detrimental to downstream filtration and separation processes, and can impact the performance of the end product as it often requires a milling process to achieve the required size.

The NiTech Crystallizer offers greatly improved control over the size and shape of crystals. Development programmes have documented major cost-savings via increased throughput and step-reduction in crystallization time.

The NiTech Crystallizer operates on a ‘plug and produce’ basis with existing manufacturing processes.