Relationship between the particle size and nutrient distribution of feces and nutrients in pigs and dairy cows and the efficiency of solid-liquid separation

Abstract

Abstract In this paper, pig and dairy manure were used as materials, and the particle size distribution of pig and dairy manure was analyzed according to different particle sizes of <0.15, 0.15-0.5, 0.5-1.0 and> 1.0mm. At the same time, NPK in four different particle sizes were analyzed. The nutrient content was solid-liquid separated by using XY-type spiral livestock and poultry manure solid-liquid separators under 0.5 and 1.0mm sieve screens. The mechanical solid-liquid separation was used to analyze the solids and nutrients of the corresponding particle size feces. Recovery efficiency. The results show that the particle size distribution of pig and cow manure is mainly <0.15mm small particles. Such small particles account for 57.99% -68.34% of the weight of the manure. The particle size of dairy manure particles is larger than that of pig manure. Less than fattening pigs and lactating cow feces. Nearly 80% of N, P, and K nutrients in pig and dairy manure are water-soluble or exist in small particles <0.15mm. The percentage of N and P nutrient recovery from solids and solids obtained from mechanical solid-liquid separation of feces is higher than the proportion of fecal particles and nutrients from the corresponding screen pore size. %, N, P nutrient recovery rates were 7.14-19.71, 7.38-21.18%, respectively.