TREATMENT AND RECYCLING ENGINEERING OF CHICKEN LITTER VIA THERMAL GASIFICATION PROCESS FOR WARMING POULTRY HOUSES

Abstract

Poultry industry, in Egypt, encounters a lot of problems and diseases especially at winter season. A lot of chicks are dying due to low temperatures at night. Poultry house warming requires a lot of energy using petroleum delivers such as liquefied petroleum gas (LPG). In this period of each year, the higher demand on LPG cylinders raises the crisis of energy shortage in Egypt. Add-value principle was considered for solving the problem. Chicken litter as a by-product of poultry production process can be recycled and reused as an alternative source of energy where there is no transportation is required especially at remote areas. Poultry house, under investigation, is located at 12 Elezbah Elbaidah village, Elhamoul district, Kafr Elsheikh governorate. According to data collected about weather conditions, the environment is almost at steady state conditions in the two months of January and February of 2016 during the period from 12:00AM to 7:00AM at 12˚C and relative humidity of 70% to be suitable for experimentation. Poultry house was divided into two longitudinal sections called raceways. Thermal gasification technique is selected for biomass (chicken litter) energy conversion. Based on energy needs for warming process, the operation parameters and investigation variables of thermal gasification process were chosen. A continuous feeding fluidized bed reactor type with a catalyst sand bed was used. The system consists of gasifier reactor, chicken litter feeding section, cleaning section of two cyclones and gasifying agent supplying section. The effect of catalyst presence percent (Dolomite) of 20, 30 and 50% in the sand bed, four levels of equivalence ratio of 0.326, 0.289, 0.227 and 0.202, three different temperature profiles of 430, 560 and 670˚C and two types of gasifying agent of natural air and mixture of air with steam are investigated. Two pathways of energy outputs; energy released to surround environment around the gasifier reactor and by the product gas. Each energy pathway was directed to a specific raceway. An air temperature change of each raceway is an indicator of energy content of each output pathway. Higher temperature profile of 670˚C contributes to higher gas yield and biomass conversion. The steam introduced with air increases the energy output by steam reforming and water gas shift reaction. Higher percent of catalyst of 50% Dolomite enhances syngas quality by reducing the amount of tar. The optimum operating conditions that meet with energy requirements of the poultry house was achieved at chicken litter feeding rate of 0.7kg/h or equivalence ratio of 0.289 and temperature profile of 670˚C and 50% of catalyst presence with gasifying agent of enriched air with steam that can change air temperature of 20˚C in ten minutes. The gasifier provides total energy (surround and syngas) of 14.97MJ/h and consumes of 1.85MJ/h. Whereas with gasifying agent of air only reduces the amount of energy consumed to 1.44MJ/h and produces total energy of 13.34MJ/h. Calorific value of syngas achieved in both cases (air with steam and air only ) are 5.75 and 5.11MJ/kg, respectively.