| The annual output of rice straw in China is huge.At present,the main utilization method is single,low utilization rate and low added value.At the same time,the seasonal lack of pasture leads to the problem of feed shortage.After the straw picking and baling is completed,leaven is sprayed,plasticized,fermented and degraded.Biodegradation technology can effectively improve the physical and chemical properties of rice straw,satisfy the taste and nutritional requirements of livestock,and increase the feeding rate of ruminants such as cattle and sheep.In the aspect of straw feeding utilization,straw picking and baling,fermentation agent spraying,plastic sealing operation and other processes are poor in fluency,resulting in the increase of costs.Therefore,the microbial degradation experiment of rice straw was carried out in this paper.The existing straw baling machine was designed with a rot agent spraying device and a plastic sealing device,and the feeding experiment after the fermentation degradation of rice straw was completed.The main research contents and conclusions of this paper are as follows:(1)Experimental study on degradation performance of rice straw after harvest.Firstly,the pre-test analysis of biodegradation of rice straw was carried out,and three leaven agents including compound bacteria,lactic acid bacteria and enzyme compound preparation were selected for control test.The results showed that the sensory evaluation of rice straw feed,such as odor and color,was improved,and the score was significantly different from that of the control group.The lactic acid bacteria + cellulase treatment group and the single lactic acid bacteria treatment group had the best sensory evaluation.The PH value of each treatment group was significantly different,and the lowest PH value of the lactobacillus + cellulase treatment group could be reduced to 3.90.The crude protein content in each treatment group was significantly different from that in the control group,among which the crude protein content in the lactobacillus + cellulase treatment group was up to 10.95%.There was no significant difference in crude fiber content between the treatment group and the control group,among which the crude fiber content in each group was 37.67 ～ 48.39%.The preliminary test proved that the microbial degradation of rice straw for forage was feasible in the low-temperature fermentation of 5-15 ℃,and the fermentation effect of the treatment group of lactobacillus preparation and lactobacillus + cellulase preparation was the best,which provided a theoretical basis for the further development of practical production test.(2)The design of key equipment for rice straw feeding.Using Solidworks to carry out3 D modeling,complete the functional principle design and transmission scheme design of the whole machine.The structure design and general parts selection of the spray mechanism andthe plastic sealing device were carried out.The spraying pressure is 0.3mpa,the nozzle type is fan-shaped nozzle 11004,the nozzle overlap rate is 40%,and the number of nozzle is 3.Finite element analysis was carried out on the shelf of liquid medicine box,and the minimum safety coefficient was 2.51,which met the use requirements.According to the working condition,the theoretical design of the plastic sealing device is carried out,and the hydraulic motor is identified as GM5-10 gear motor.The finite element analysis is carried out on the supporting roller of the plastic sealing mechanism.The minimum safety factor is 16.2,which meets the requirements of operation.(3)Based on the degradation performance experiment of rice straw and the design of supporting equipment,the production experiment was carried out to determine the process parameters of rice straw feeding and the mechanization production process.The results showed that the fermentation effect of lactic acid bacteria and cellulase starter was the best,and the best quality was about 30 ～ 60 d.The crude fiber content can be reduced to 34.55%,the crude protein content can be increased to 10.12%,and the soluble sugar content can reach11.3%.In the experiment of Simon cattle feeding with fermented straw feed,the feeding rate was nearly 100%,which was 72% higher than that of rice straw without fermentation,and the feeding rate difference was very significant(P < 0.01).In this paper,through the study on microbial degradation of rice straw,rice straw feed technology was proposed,based on the degradation experiment,the existing mechanical step by step(collecting,baling,encapsulation,the decomposing agent spraying)operation was improved design,increased the decomposing and agent spraying and powder coating equipment,implements the rice straw feed joint operations.Compared with the multi-step operation,the combined operation cost of the whole set of equipment is reduced and considerable economic benefits are obtained,which lays a foundation for the demonstration and popularization of rice straw feeding technology. |
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