4. Conclusion
The performance of a collector solar tunnel dryer for drying Andrographis paniculata has been
investigated in June. Two experiments were carried out 100 kg of Andrographis paniculata can be dried in2 days. It was found that its performance is better than natural sun drying. The dryer could be used forAndrographis paniculata of 75% (wb) moisture content, and they could be dried within 2 days, with 7%(wb) remaining moister. Temperatures in the drying chamber varied from 35° C to 75° C. The problem oflosses due to a contamination by insect and animal and rewetting by rain was overcome. The driedproducts of high quality were obtained.