Heated Filter Box
In Method 5 and other methods for out-of-stack measurement of stack emissions, when sampling for particulate matte, it is mandatory for the sample to be drawn iso-kinetically. The sample is drawn through a probe and is collected on a glass fiber filter. In order to prevent loss of particulates to water that may form due to condensation of water vapour present in the sampled stack gas , the probe and the filter are required to be maintained typically at a temperature of 120 ± 14 °C (248 ± 25 °F).
This necessitates the filter holders also to be maintained at the above mentioned temperatures in addition to heating the sampling probes.
Polltech's heated filter box Model PEM–HFB2 meets these requirements adequately. It comprises a double walled thermally insulated, electrically heated compartment. It is capable of accepting a glass or PTFE filter holders of various sizes. Uniform heating is provide by a large area sealed tubular heater element. Heated probes are held in place by a strong SS probe clamp. An independent electronic module comprising two digital electronic temperature controllers control and display the temperatures in real time.
Detailed Technical Specifications :
| Construction Design | Double walled with ceramic wool insulation |
| Construction Material | Powder Coated Aluminum, Anodized Aluminum, SS |
| Filter paper size | 70, 90 mm dia. or custom specified |
| Filter Holder | Glass or PTFE |
| Probe Clamp Holder | SS for 38 mm dia. Probe |
| Removable Probe Liner | Not applicable |
| Standard Length ( Meters) | Not applicable |
| Heating Method | Electrical Resistance Heater |
| Temperature Range | 50 to 2000 °C |
| Temperature Sensor | Thermocouple : Type K |
| Temperature Controller | 2 Numbers - Electronic Closed Loop Feedback Type with digital display for set and actual temperature mounted in Electronic Unit |
| Measurement / Control Accuracy | Better than 50 °C |
| Power & Temperature Sensor Connectors | Total 4 Nos. Mil grade threaded type |
| Connections-Inlet | 5/8” Swagelok |
| Connections-Outlet | Push-fit Union for 12mm PU tube |
| Dimensions | 26 x 26 x 37 cm |
| Weight | 7 kg |
| Electronic Unit Dimensions | 11 X 13 X 27 cm |
| Electronic Unit Weight | 2 kg |