Examples of mechanical dryers

Many mechanical dryers have been developed for rice but only very few did get commercialized successfully. This page provides some information about some dryers that became popular in Southeast Asia. It does not constitute a comprehensive overview of all possible drying technologies. The dryers featured here are not necessarily the best technical solution but, because the users accept them, they seem to offer a good compromise between drying cost and benefits in terms of higher quality and weather risk avoidance in their specific settings.

Overview on commercially available dryers

Target group	Dryer	Description
Farm level		Low Cost Dryer (SRR and STR dryers) Country: Vietnam Source: Nong Lam University (NLU), Ho Chi Minh City Capacity: 1t Drying time: 2 days Cost: US$ 100 (1997) Installed units in 2009: more than 1,400 Contact: NLU
Farm level		Solar Bubble Dryer (SBD) Joint development, IRRI, GrainPro, University of Hohenheim Source: GrainPro Inc., Philippines Capacity: 0.5t, 1t Drying time: 1-2 days Cost: US$ 1,000-2,000 Sold units in 2015: 50 Contact: GrainPro, IRRI
Drying contract service provider Small to medium rice mills		Vietnamese Flat Bed Dryer Country: Vietnam Source: Nong Lam University, Ho Chi Minh City Capacity: 4-20t Drying time: 6-8h Drying rate: 1-1.5%/h Cost: US$ 1,500 (2009) Installed units in 2009: more than 6,000 Contact:NLU
		Vietnamese Reversible Airflow Flat Bed Dryer Country: Vietnam Source: Nong Lam University, Ho Chi Minh City Capacity: 4-20t Drying time: 6-8h Drying rate: 1-1.5%/h Cost: inquire Installed units: most new installations Contact:NLU
		Maligaya Flat Bed Dryer Country: Philippines Source: NLU - PhilRice cooperation Capacity: 4t Drying time: 6-8h Drying rate: 1/1-5%/h Contact: PhilRice
		PhilRice Reversible Airflow Flat Bed Dryer Country: Philippines Source: NLU - PhilRice cooperation Capacity: 4-6t Drying time: 6-8h Drying rate: 1/1-5%/h Contact: PhilRice
		Cambodian Flat Bed Dryer Source: NLU, Vietnam through IRRC Capacity: 4t Drying time: 6-8h Installed units until 2009: 7 Installed units until 2012: more than 100 Contact: MAFF
		Myanmar 4t Flat Bed Dryer Source: NLU, Vietnam through IRRC Capacity: 4t Drying time: 6-8h Drying rate: 1-1.5%/h Installed units until 2009: 7 Installed units until 2012: more than 350 Contact: Pioneer Postharvest Development Group
		Myanmar 1-3t Flat Bed Dryer Source: Pioneer Postharvest Development Group Capacity: 1-3t Drying time: 6-8h Drying rate: 1-1.5%/h Installed units: A few, mostly for demonstration Contact: Pioneer Postharvest Development Group
		Indonesian Box Dryer Source: ICRR, Sukamandi Capacity: 3.3t Drying time: 6-8h Installed units until 2009: 200 Contact: Indonesian Center for Rice Research, Sukamandi BPTP South Sumatra: Budi Rahario
Large rice mills and processors		Commercial Re-circulating Batch Dryer Source: Various companies Capacity: 4-20t/batch Drying time: 6-8h Drying rate: 1-1.5%/h These dryers are available from different sources IRRI assisted in the development in Vietnam and Cambodia
Small seed dryers		IRRI Flat Bed Dryer Source: IRRI Capacity: 1t Drying time: 6-8h Note: This is a design from the 1970s. Thousands of units were installed over the years but the design is outdated. It can still be used for drying seeds or demonstation purposes since it can be made portable. Contact: postharvest@irri.org
Small seed dryers		IRRI Seed Dryer Source: IRRI, based on the Vietnamese SRR dryer Capacity: 200 kg Drying time: 12-24h Note: This is a prototype seed dryer for very small seed samples. The IRRI design uses a rice husk stove as heat source but that is very labor intensive. A coal stove using brickets is more appropriate. Contact: postharvest@irri.org

Examples of mechanical dryers

Guidelines on using mechanical dryers

Troubleshooting mechanical dryers

Fixed-bed batch dryer

Re-circulating batch dryer

Continuous flow dryer

Flash dryer