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This chapter describes a process for eliminating the current practice of dumping unwanted rice production waste, and uncontrolled burning of wastes in the field. Widescale rice husk conversion systems remain constrained by limited regionally-specific agronomic research on the efficacy of the resultant carbonised waste biochar on rice yields, fertilizer use efficiency, and stable carbon fractions for reliable and safe soil carbon biosequestration practices, as well as the economic incentives for farmers to integrate waste conversion technologies into rice farms. In this study a carbonizer technology was developed and applied to the rice production systems currently used in rural areas of the Philippines. The carbonizer prototypes were fabricated at the Philippine Rice Research Institute (PhilRice) machine shop in Muñoz Science City, Nueva Ecija, Philippines, and used similar manufacturing techniques commonly used in the local machine shops, i.e., with locally available equipments, skills, and parts. Results from the second refined prototype demonstrated a processing capacity of up to 40 kg hr-1 of rice husk into biochar, with around 40% in biochar yield (by mass), and a biochar purity of approximately 99%. The refined prototype has a smokeless chimney emission during operation and carbon monoxide emissions were greatly reduced (431 ppm). The carbonizer enables waste heat extraction using exchangers or microboilers, with heat produced during combustion available as additional source of energy to partially replace kerosene and firewood currently used. This additional energy source from the use of agriculture waste in carbonizers can play a vital role in protecting the forests in rural Philippines, whereas population growth and current practices (kerosene and firewood from unmanaged forests) are drivers to illegal deforestation. The adoption of carbonizers can increase carbon sequestration by decreasing firewood demand and avoiding deforestation, (a REDD activity), and the application of biochar for fertilizer further reducing net emissions in the region through soil carbon storage. By increasing aboveground and belowground carbon stocks in the agro-ecosystem, carbonizers can be used strategically for sustainable resource management and as a important tool for reducing emissions as an effective and practical climate change mitigation strategy. © 2015 Nova Science Publishers, Inc.
