# A Design of a Solar Fermentation System on Chicken Manure by Fuzzy Logic Temperature Control
## 1 Introduction  
Animals' manure contains 70-90% organic matter, nitrogen, phosphorus and may causes pollutants without proper disposal. For example, each chicken has a daily exceta discharge of 52-81 g with 50.5% water content, which contains 25.5% of organic matter, 1.63% of nitrogen, and 1.54% of phosphorus [1]. The manure potentially has a high concentration of pollutants; on the other hand it is also the nutrients required by plants, such as production and utilization of compost in Taiwan by a livestock research institute [2]. It can be seen on the report discussing the development and application of new biological fertilizers in Taiwan [3], and also the report referring the production and use of organic fertilizer [4]. Proper disposal and reuse of the manure could achieve the purpose of compost resource. At present, the treatment methods of livestock manure mainly include solid liquid separation, anaerobic treatment, and aerobic treatment. The deficiency of the traditional composting method is that it is flipped and stacked for 1 to 3 months, and there are problems such as stinking, sewage, and large stacking space. Therefore, the current composting manufacturing method has become mechanized, and a ventilation system is applied to shorten the fermentation time. Traditional composting methods utilize microorganisms in nature to decompose the unstable organic components in the waste under controlled conditions and convert them into a stable humic acid (HA) component, which is called \"compost\", such as the research of [PERSON] et al. [5], [PERSON] et al. [6], and [PERSON]'s thesis [7]. In the process of composting, microorganisms alwaysplay an important role in the decomposition of organic matter and the stabilization of compost. During the composting process, the carbohydrates contained in the organic matter are rapidly decomposed by microorganisms, and the proliferation of microorganisms is required to absorb nitrogen, phosphorus and other nutrients to combine synthetic microbial constitution (biomass) [8,9]. Different stacked materials are inoculated with appropriate microbial strains to accelerate composting. In addition, maintaining the optimal growth conditions of the microorganisms and allowing the microorganisms to fully move and reproduce can enhance the fermentation and decomposition of the compost material as well. For green energy applying to fermentation, different inventions and techniques aimed at providing solar heat fermentation equipment were designed to treat biowaste, such as a China Patent in 2009 [10] and another China Patent in 2014 [11], or even produce bioethanol [12]. However, in order to maintain a suitable temperature for microbial fermentation, a solar temperature-controlled livestock manure fermentation system was designed in the current study [13]; it aims to effectively control the temperature of the fermentation tank by fuzzy logic algorithm and shorten the fermentation time by using solar heating. Fuzzy Logic Control (FLC) linearly interpolating any value between zero and one differs from traditional controls of zero and one only [14]. Currently, FLC technology is widely used in optimal design of the fuzzy Proportional Integral Derivative (PID) controllers [15], DC-to-DC converter in microcontrollers [16], fuzzy logic controller (FLC) for a Pulse Width Modulation (PWM) boost converter [17], and DC Servo Motor fuzzy control [18]. The present study applied the FLC technology on the solar water heater of the temperature controller to maintain a constant temperature in the tank with the intelligent solar fermentation system for optimal fermentation temperature conditions. Here in this study, the Tsukamoto fuzzy model [19] is used to aggregate the output of each rule and the center-of-gravity method is also used as defuzzification, which can meet the relative simplicity and needs of practical agricultural applications.