Methods to Reduce Dust in Coffee Processing Facilities

Installing dust-extraction systems and mist-spraying machines can reduce dust in coffee processing plants by up to 95%.

Coffee Processing Facilities Struggle with Dust

Dak Lak Province, Vietnam’s largest coffee-growing region, plays a key role in the national economy. In recent years, both the area and output of coffee in Dak Lak have continued to increase.

• In 2021, Dak Lak’s total coffee area reached 209,000 hectares, of which 178,571 hectares were harvested, producing 2.25 million tons of fresh coffee cherries and 500,000 tons of green coffee beans.

• Compared to 2015, the coffee area increased by 5,643 hectares, and production rose by 224,950 tons.

• Alongside this growth, the number of coffee processing enterprises and facilities has also expanded.

According to the Institute of Agricultural Environment, in 2020, Dak Lak had 301 coffee processing and preliminary processing facilities, including 252 household operations and 49 enterprises.

• Total processing capacity of green coffee reached 2,509,466 tons,

• and the output of green coffee beans was 557,000 tons.

In the Central Highlands, most coffee is processed using the dry method. In Dak Lak, 85% of facilities use dry processing, while only 15% use the wet method.

However, emissions and dust generated during the transport of raw materials, machine operation, and preliminary processing are largely uncontrolled.

Currently, most preliminary processing households use agricultural by-products (wood, corn cobs, coffee husks, rice husks) as fuel. This produces lower levels of SO₂, NO₂, CO, and CO₂ emissions compared to coal or oil.

Nevertheless, methods to reduce gas and dust emissions in coffee processing facilities are necessary to protect workers’ health and the surrounding environment.

Research and Pilot Model

The Institute of Agricultural Environment, under the Ministry of Agriculture and Rural Development, carried out a project titled:

“Investigation and Assessment of the Environmental Impact of Agricultural Processing Facilities (cassava, coffee), Wood and Bamboo Craft Villages, and Proposals for Sustainable Environmental Protection Solutions.”

As part of this project, researchers developed a cleaner production model to reduce dust pollution in several dry coffee processing facilities in Hoa Dong Commune, Krong Pac District, Dak Lak Province.

Reducing Dust by Around 95%

The model was applied at two facilities:

• Mr. Le Xuan Hoi’s coffee processing facility (Thon 15, Hoa Dong Commune) with a 15-ton/day capacity, and

• Mr. Nguyen Dinh Binh’s facility (Lien Co Hamlet, Hoa Dong Commune) with a 13-ton/day capacity.

Mr. Le Xuan Hoi shared:

“Our facility processes coffee using the dry method, handling about 15 tons of fresh coffee cherries per day. During drying, the smoke was so heavy it blanketed the area, and the smell of drying cherries caused headaches, affecting workers’ health.”

After the Institute of Agricultural Environment installed a model including a dust-extraction system (capacity 25,000 m³/h) integrated into the coffee hulling stage, along with a mist-spraying system around the workshop:

• Dust was almost completely eliminated,

• The working environment improved significantly.

The model successfully reduced dust by 90–95%, creating a much better environment. Workers no longer experienced nasal irritation.

However, smoke from the drying kilns remains a problem:

“Whenever the kilns operate, smoke still spreads across the area,” Mr. Hoi admitted.

Mr. Nguyen Dinh Binh, owner of another facility in Lien Co Hamlet, said:

“Our facility has operated for three years, with an investment of about 700 million VND, processing 13 tons of coffee per day. When the Institute surveyed facilities for a pilot model, ours was selected. We were provided with a 25,000 m³/h dust-extraction system and a mist-spraying system.

Although the model has only been in place for a short time, it has already reduced dust by more than 95%. To the naked eye, there is almost no dust visible. However, smoke from the drying kilns remains unresolved.”

Neighbor Mr. Pham Van Trung added:

“Previously, smoke and dust from this facility were unbearable; we couldn’t sleep at night. Coffee trees near the kilns were covered in dust and dried out; only rain or irrigation could wash it away. After the dust-extraction system was installed, the dust decreased significantly.”

Need to Replicate the Model

According to Mr. Pham Van Ha, Vice Chairman of Hoa Dong Commune:

“Since the dust-control systems were installed at Mr. Binh’s and Mr. Hoi’s facilities, visible dust emissions have been reduced by about 85–90% compared to before.”

Dr. Ha Manh Thang (Institute of Agricultural Environment), project leader, reported:

• Air sample tests before and after installation showed a 90–95% reduction in total dust concentration.

• Furthermore, the equipment is simple to install and operate, and collected dust from the fabric filter bags can be processed into organic fertilizer for coffee plants and other crops.

This both reduces environmental pollution and saves fertilizer costs for coffee production and agriculture.

Legal and Policy Framework

Vietnam’s 2020 Law on Environmental Protection, Article 56, Clause 2, requires:

• Household-scale producers must implement environmental protection measures in accordance with the law,

• including reducing noise, vibration, light, dust, heat radiation, gas emissions, and wastewater,

• and properly collecting, classifying, and treating solid waste.

In addition, Government Decree No. 45/2022/ND-CP (dated July 7, 2022) on administrative penalties in environmental protection adds provisions for regulating environmental protection in production facilities, business clusters, industrial zones, and craft villages.

Moving Toward Sustainable Coffee Production

Reducing smoke and dust emissions in coffee processing facilities is therefore both necessary and legally required.

In the coming years, similar environmental protection models should be expanded and replicated in coffee preliminary processing and production facilities to:

• reduce environmental pollution,

• improve product quality, and

• promote sustainable coffee production.