An integrated eco-system for pollution prevention and greening the production chain of small-scale rice-paper production: A case study from Vietnam

In this study, we developed and demonstrated an integrated closed eco-system for pollution reduction and prevention in rice-paper producing and livestock farms in a small-scale craft village which is located in a dry region of Vietnam with a lack of available surface water sources. The system is developed on the basis of material and energy exchange potentials between the wastewater and exhaust gas flows, and the use of available firewood ash as material for absorption. Two operation modes were presented aiming at a complete treatment of wastewater and exhaust gases as required by the Vietnamese national standards, and the recovery of valuable components in the system (N, P) for obtaining value-added products (such as fertilizer, irrigation water, etc.). In addition, the maximization of potentials on existing natural conditions at the local family, the avoidance of chemicals used in the system etc. have also helped to lower the investment and operation costs of the treatment facilities. The application of this system also contributes to the “greening” of the rice production chain in the Mekong Delta, Vietnam and is an example for a local closed cycle economy. Several public activities have also been conducted at the demonstration site (at the local family) with the purpose of maintaining and multiplying the system's effectiveness among the local public community.