Camfil Farr Air Pollution Control
 Dust collector extends filters’ service lives


 The Gold Series High Vacuum (GSHV) dust collector from Camfil Farr Air Pollution Control (Jonesboro, AR) controls emissions in applications performed under pressures as high as 17 in. Hg vacuum or 8 psi. The unit is housed in a reinforced dust-capture vessel designed for use as a central vacuum system, positive or negative product receiver, or high-pressure bin vent. The GSHV collector can be provided with two or four Gold Cone HemiPleat filter cartridges, which are available in efficiencies of 99.99% and 99.999% on 0.5-µm particles.

The machine’s cyclonic tangential inlet removes most of the dust as it enters the collector, thus minimizing filters’ contact with the dust and extending their service lives. The device also includes a pulse-cleaning system that operators regulate through a user-friendly, solid-state control panel. The dust collector is available with a horizontal explosion vent for combustible-dust applications and a bag-in–bag-out access door and continuous liner discharge for pharmaceutical dusts.

K-Tron 
 Material flow aid prevents bridging and rat-holing


K-Tron (Pitman, NJ) offers its ActiFlow bulk-solids activator, a nonproduct contact device that comprises a vibratory drive and an intelligent control unit. The device operates with the K-Tron Control Module (KCM) to activate the material inside the hopper continuously. The KCM unit’s self-tuning algorithm monitors the system and continuously adjusts the ActiFlow’s frequency and amplitude, according to changing material-flow conditions, to maintain flow within the hopper. The activator and KCM thus prevent the formation of bridges and ratholes. 

The ActiFlow machine is designed to eliminate the need for mechanical agitators with secondary motors and gearboxes and to eliminate the need for flexible side-wall agitation devices or aeration pads. The ActiFlow device is bolted to the outside of the extension hopper’s rear wall above the feeder, thus reducing headroom requirements. ActiFlow is designed to simplify the cleaning process during material changeover and is suitable for pharmaceutical applications. 

Articles

PharmTech's monthly newsletter, Equipment and Processing Report, reviews the Editor's Picks for the April 2010 edition from Camfil Farr and K-Tron.

April 2010 Editor's Picks: Products from Camfil Farr and K-Tron

The green movement promises to make life-sciences manufacturing processes more environmentally friendly. Manufacturers who believe green initiatives are the right thing to do-for the environment and for long-term business sustainability-are embracing the chance to reduce their carbon footprints by switching to renewable energy sources and decreasing water and energy usage. Industry leaders are starting to monitor energy usage better and evaluate ways to conserve natural resources whenever possible without sacrificing product quality. 


Before setting goals for reducing energy consumption, manufacturers first need to have a baseline measurement of current use to help establish realistic goals and report improvements with confidence. Analytical software can improve the measurement and reporting of criteria such as how much energy was used to produce a unit of product. From an economic perspective, this information lets manufacturers normalize spending comparisons on an energy-cost-per-unit basis. Companies typically think of energy use in relation to time, but that perspective does not aid in decision making because the level of manufacturing output within a plant can vary greatly. 

With the right software, it is simple to analyze the amount of energy used to manufacture a unit by comparing baseline measurements with energy-measurement parameters obtained from existing control systems. A data-integration platform such as Aegis Analytical’s (Lafayette, CO) Discoverant is useful, as are process-data historians like OSIsoft’s (San Leandro, CA) Pi System, or process-control systems from Emerson (Austin, TX), Foxboro (Plano, TX), or Rockwell Automation (Milwaukee). 


Once a company has set goals and is measuring energy use in relation to the units produced, software tools help compare various operating units to evaluate the energy use and cost of similar equipment at a given site. For example, an active pharmaceutical ingredient may be processed in two dryers that perform similar operations but are made by different manufacturers. The drying operation offers a good starting opportunity to save energy through monitoring because dryers consume a lot of energy and include multiple components that can cause inefficiencies. 

Analysis might show that one dryer uses considerably more energy than another. Rather than examining only the initial costs of the dryers, a company can compare them by assessing their actual operating costs per unit. It may be necessary to add or modify a specific energy-use measurement to the device (e.g., steam usage for heating the dryer). A company also might compare the cost per unit produced of two process trains. Operators might, for example, try to determine why one train exhibits higher absorption rates on a product and uses valuable energy. Ultimately, such information allows the company to make green equipment purchasing and operating decisions according to data-based comparisons that identify the most energy-efficient equipment vendors. 

Another useful application of analytical software is monitoring the effect of maintenance events on energy-use reduction. A company might choose to track the cleaning process for a heat exchanger in a production line. In theory, the cleaning will increase the heat exchanger’s energy efficiency and, thus, reduce the amount of energy required to do a given job. A company can monitor energy usage to see whether cleaning has this effect. If it does not, the company might be wasting valuable maintenance and personnel time without gaining a return. 

Similarly, a company can make site-to-site comparisons to investigate why a process consumes more energy at one location than at another. An analysis of groups of equipment can enable a comparison of sites’ costs. An older plant with inefficient equipment may be in a location where energy is cheaper. Taking into account the cost of energy as well as the use of energy can help the company take actions consistent with its overall green goals. Will the company first replace inefficient equipment at a site where energy costs less or more?

Gathering and analyzing the right data can help companies set goals and monitor processes to better understand and reduce energy usage and expenditures at manufacturing facilities. By adding a few parameters to software based on utility usage and integrating that information with supply-chain and process data, manufacturers can get a better handle on where they currently stand and discover specific ways to reduce their energy waste and costs.


Randy Tatlock is senior applications specialist at Aegis Analytical, 1380 Forest Park Circle, Suite 200, Lafayette, CO 80026, tel. 303.625.2100, 

In the Mixer

The green movement promises to make life-sciences manufacturing processes more environmentally friendly.

Using Existing Software to Track and Reduce Utility Use

If you’ve worked in the drug industry for a while, chances are good that you remember Pfizer’s (New York) Rezulin, which was produced through hot melt extrusion (HME). If you work for a major pharmaceutical manufacturer, it’s likely that your company owns a twin-screw extruder. Yet HME has not been a common way of manufacturing drugs, and many industry employees don’t understand the principles of HME or the advantages that the technique offers.

Extrusion is the process of forcing ingredients through an orifice or die under controlled conditions (e.g., temperature, feed rate, and pressure) to form a new material (1). More than 90% of the extruders at pharmaceutical companies are twin-screw models, says Charlie Martin, general manager of Leistritz. Twin-screw extruders mix materials better than single-screw extruders and are better suited to pharmaceutical processes.

One major advantage of HME is that it is a continuous process that requires less offline testing compared with batch processes, says Martin. Like all continuous processes, HME requires fewer operator interventions than batch processes do and, thus, can yield improved product quality. The technique also is compatible with process analytical technology and can be scaled up easily.

Operators can use HME to form solid dispersions in a continuous process but, unlike spray drying, solvent evaporation, and coprecipitation techniques, HME does not require organic or hazardous solvents. Nor does the process require water or drying equipment. For these reasons, HME enables manufacturers to reduce expenses and conserve space on the plant floor. In addition, the process could replace solid-dosage unit operations such as blending, granulation, and particle sizing, says Firouz Asgarzadeh, principal scientist at Evonik.

HME is not limited to producing solid dosage forms, however. Operators can use the process to create multilayer transdermal patches, implants, dissolvable strips, and foams. Any extruder can produce any of these products, only the die and the downstream handling must be adjusted, says Martin.

HME also can modify drugs’ characteristics. Many new active pharmaceutical ingredients (APIs) have big molecular structures and are consequently difficult to dissolve, but HME can enhance these substances’ solubility, according to Peter von Hoffmann, general manager of engineering plastics and special applications at Coperion. The high temperatures and shear in the HME process can bring poorly soluble drugs with a crystalline structure into a stabilized, amorphous state that is more soluble. HME also can maintain a drug’s crystalline structure, but make the crystals finer and the particle size smaller to improve solubility.

Because the process works with insoluble APIs, it sometimes enables drug loading of 80–90%. In addition, operators can modify a drug’s release rate by blending the appropriate polymers with it in the extruder.

HME technology has become easier for the industry to adopt, thanks to the technical developments of recent years. For starters, extruder vendors have begun to produce units designed according to the principles of good manufacturing practice. These companies have adapted their production processes and the documentation that is the basis for qualifying the extruders, says Hoffman.

Some new extruders enable pharmaceutical manufacturers to add potent substances into the carrier matrix. These substances can be APIs that are mutagenic, carcinogenic, and dangerous to produce, Hoffman says.

Other vendors have developed corotating twin extruders with self-wiping screw profiles. The screw flights on these machines wipe the adjacent screw roots, thus allowing the extruders to be emptied fully. These extruders have enabled manufacturers to produce pharmaceutical products efficiently with short residence times, minimized thermal degradation, and enabled high content uniformity. Asgarzadeh has used these machines to develop soluble formulations of poorly soluble drug substances and to develop controlled-release drug-delivery systems. 

One big obstacle to the industry’s adoption of HME has been that in the initial phases of development, pharmaceutical companies have limited amounts of API and no way to test it except in a full-batch mixing bowl. During the past two years, however, extruder design has fundamentally changed to allow small batches (e.g., 5–20 g) of candidate APIs to be tested in a continuous way, says Martin. Manufacturers now can experiment to determine whether HME is an appropriate processing method for a new drug candidate.

The pharmaceutical industry has not used HME to manufacture many of its medicines, perhaps because it has been largely unfamiliar with the process. Companies could use the technology to create many dosage forms, however, and the process could enable the manufacture of drugs that otherwise would remain unmarketed. As a continuous technique, HME likely would be favored by the US Food and Drug Administration and yield dosage forms of consistently high quality, says Martin. The process also seems to hold the promise of greater efficiency and reduced operating expenses. Given these advantages, the adoption of HME may become more widespread in the near future.

Production Lines

If you’ve worked in the drug industry for a while, chances are good that you remember Pfizer’s Rezulin, which was produced through hot melt extrusion (HME). If you work for a major pharmaceutical manufacturer, it’s likely that your company owns a twin-screw extruder. Yet HME has not been a common way of manufacturing drugs, and many industry employees don’t understand the principles of HME or the advantages that the technique offers.

Equipment and Processing Report-04-19-2010

April 2010 Editor's Picks: Products from Camfil Farr and K-Tron

Using Existing Software to Track and Reduce Utility Use

Is Hot Melt Extrusion an Untapped Resource?