Present Situation Analysis And Evaluation Of Commercial Organic Fertilizer And Its Raw Materials In Sichuan Province

With the advancement of technology and production levels,the demand for organic fertilizers has been rising year by year.However,the production of organic fertilizers is restricted by the production of raw materials and production technologies.Some of the finished organic fertilizers have certain quality risks,such as excessive heavy metals,etc.If it is used in large quantities for a long time,it may cause soil contamination.Therefore,it is particularly important to understand the condition of organic fertilizers,especially the content of nutrients and heavy metals.This paper investigates the nutrient and heavy metal contents of the main organic fertilizers and organic fertilizer raw materials in Sichuan Province from 2014 to 2017 and draws the following conclusions:（1）According to the organic fertilizer industry standard（NY525-2012）of the total nutrients quality requirements（nitrogen+phosphorus pentoxide+potassium oxide）≥5.0%of the,the total organic nutrient content of finished organic fertilizer was measured in organic fertilizer from 2014 to 2017 in Sichuan Province was 9.1%,The average content of organic matter is 61.43%,the overall average content of moisture is 34.89%,the overall content of pH is 4.1～12.7,and the average value is 7.0.The average contents of total arsenic,total mercury,total chromium,total cadmium,and total lead in Sichuan Province from 2014 to 2017 were4.84mg.kg^-1,0.52mg.kg^-1,22.50mg.kg^-1,1.48mg.kg^-1,11.76mg.kg^-1.The total qualified rate of heavy metals total arsenic,total mercury,total lead,total cadmium,and total chromium in commodity organic fertilizers were:95.83%,93.26%,96.81%,94.79%,98.84%.（2）The average content of total nutrients in the preparation of organic fertilizer was6.62%.The average content of total arsenic,total mercury,total lead,total cadmium,and total chromium in the raw materials for the preparation of organic fertilizers was successively 3.50 mg.kg^-1,1.16mg.kg^-1,16.61mg.kg^-1,0.91mg.kg^-1,50.76 mg.kg^-1.Excess samples in 2014 were mainly concentrated in the total lead and total chromium in sludge and manure.In 2015,the excess samples were mainly concentrated in total arsenic in coal,total cadmium,total mercury,total lead in sludge,and individual finished organic products.In the indicators of total arsenic,total mercury,total chromium,total cadmium,and total lead of fertilizers,the excess samples in 2016 were mainly concentrated in the total mercury of individual finished organic fertilizers.And in 2017,the excess samples were mainly concentrated in the total mercury of sludge,total Chromium,total cadmium,total lead,total mercury in manure,total cadmium in biogas residue,and total arsenic,total mercury,total cadmium,total lead in individual finished organic fertilizers.（3）Sludge in Sichuan Province is not suitable for raw materials of organic fertilizers,which mainly due to the indicators of heavy metals are more common than standard.If it is used as raw material for organic fertilizer,I recommended not to make the main material.,and small amounts are more suitable for accessories;other organic fertilizers e.g.chickens Feces,pig manure,cow dung,and slag are all suitable as the main raw materials for organic fertilizers.For individual samples such as substrates,peat soil,distiller’s grains,and coal,the total nutrient or organic matter and pH value are unqualified,such as biogas residue and coal.If the indicator is slightly over-specified,it can be used as the main raw material for organic fertilizers by appropriately regulating and processing it.