Method for treating bone gelatin solid waste

Abstract

The invention discloses a method for treating bone gelatin solid waste, and relates to the technical field of bone gelatin solid waste treatment.The method comprises the following steps that bone gelatin solid waste with the initial water content being 50%-70% is aired in the sun till the water content is 20%-40%, then a compound fermentation inoculant is added, the mixture is stirred to be uniform, fermentation is conducted, and dehydrated solid waste with the water content reduced to 20% or below is obtained; calcining the dehydrated solid waste at 840-860 DEG C to obtain a mixture containing calcium oxide and calcium phosphate; dissolving the mixture in water to form an emulsion, then adding a monocalcium phosphate-hydrochloric acid mixed solution, and controlling the pH value to be 6.5-7 to obtain calcium hydrophosphate; on one hand, the cost for purchasing calcium hydrophosphate is saved, the treatment cost for entrusting a third-party mechanism to treat the bone gelatin solid waste is also saved, and meanwhile, the generated mother liquor can be recycled for the procedure of acid leaching of the aggregate in the bone gelatin production process, so that the utilization rate of the bone gelatin solid waste is further improved, and the purpose of turning waste into wealth in a real sense is achieved; certain economic benefits are brought to manufacturers, and certain commercial value is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of bone gelatin solid waste treatment, and in particular to a method for treating bone gelatin solid waste. Background Art

[0002] As an important biopolymer material, bone gelatin has a wide range of applications in food, medicine, photography, and other fields. The production of bone gelatin generates a large amount of solid waste. This waste primarily consists of the residue left after pre-processing and gelatin extraction from animal bones, as well as waste residue and other waste materials generated during the production process.

[0003] The bone gelatin currently produced is mainly produced with aggregates (cow bones, pig bones, sheep bones, etc.). In the process of gelatin production, bone gelatin solid waste with a water content of about 60% is generated every day. Among the dry components of bone gelatin solid waste, organic matter accounts for about 30%, calcium carbonate and calcium hydroxide content is about 45%, and calcium phosphate content is about 25%. At present, the bone gelatin solid waste generated by manufacturers in the production of bone gelatin is usually entrusted to a third party for treatment, and the treatment fee is about 65 yuan / ton. For manufacturers, this not only means that part of the treatment fee needs to be paid, but also means giving up the opportunity to utilize the bone gelatin solid waste, which is not conducive to the economic benefits of the manufacturers. Summary of the Invention

[0004] The object of the present invention is to provide a method for treating bone gelatin solid waste to solve the following technical problems:

[0005] How to improve the utilization rate of bone gelatin solid waste.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] The present invention discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0008] Step 1: Dry the bone gelatin solid waste with an initial moisture content of 50-70% in the sun until the moisture content is 20-40%, then add a composite fermentation agent and stir evenly, and ferment at 45-60° C. for 3-4 days to obtain dehydrated solid waste; at this time, the moisture content of the dehydrated solid waste can be reduced to below 20%.

[0009] Step 2: calcining the dehydrated solid waste at 840-860° C. for 1-1.5 hours to obtain a mixture containing calcium oxide and calcium phosphate;

[0010] Step 3: dissolving the mixture in water to form an emulsion, then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, controlling the pH to 6.5-7, and performing solid-liquid separation after the reaction is completed to obtain calcium dihydrogen phosphate.

[0011] Furthermore, in step 1, the composite fermentation agent is a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus in a ratio of 1:2 in terms of viable bacteria count.

[0012] Furthermore, the inoculation amount of the composite fermentation bacteria agent is 0.5-1.0% of the dry weight of the bone gelatin solid waste.

[0013] Furthermore, in step 2, nitrogen is introduced during the calcination process for protection, and the oxygen concentration is ≤5%.

[0014] Furthermore, in step three, the mass fraction of the emulsion is 25-35%.

[0015] Preferably, the mass fraction of the emulsion is 30%.

[0016] Furthermore, in step three, the concentration of calcium dihydrogen phosphate in the calcium dihydrogen phosphate-hydrochloric acid mixture is 1.2 mol / L, and the concentration of hydrochloric acid is 0.3 mol / L.

[0017] Furthermore, in step three, the volume ratio of the emulsion to the mixed solution of calcium dihydrogen phosphate-hydrochloric acid is 1:(1.3-1.5).

[0018] Preferably, the volume ratio of the emulsion to the mixed solution of calcium dihydrogen phosphate-hydrochloric acid is 1:1.4.

[0019] Furthermore, in step three, a filter press is used to perform solid-liquid separation to obtain a wet cake and a mother liquor, and the wet cake is washed to obtain calcium hydrogen phosphate.

[0020] Furthermore, the washing method is: countercurrent washing is performed with pure water and wet cake in a weight ratio of 1:0.8, and the washing times are 2-3 times.

[0021] Furthermore, the mother liquor is reused in the aggregate acid leaching process during the production of bone gelatin.

[0022] Beneficial effects of the present invention:

[0023] In the method for treating bone gelatin solid waste provided by the present invention, the bone gelatin solid waste is first dried in the sun to reduce the water content from 50-70% to 20-40%, and then fermented to further reduce the water content to below 20%, and then calcined at 840-860° C. to generate calcium oxide and calcium phosphate, and finally reacted with a mixture of calcium dihydrogen phosphate and hydrochloric acid to obtain calcium hydrogen phosphate. The calcium hydrogen phosphate is an important chemical raw material, which saves the cost of purchasing calcium hydrogen phosphate and the cost of entrusting a third party to treat the bone gelatin solid waste. At the same time, the generated mother liquor can be reused in the process of acid leaching aggregates in the bone gelatin production process, further improving the utilization rate of the bone gelatin solid waste, realizing the true transformation of waste into treasure, bringing certain economic benefits to manufacturers, and having certain commercial value. DETAILED DESCRIPTION

[0024] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0025] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0026] Step 1: Sun-drying bone gelatin solid waste with an initial moisture content of 50-70% to a moisture content of 20-40%, adding a composite fermentation agent and stirring evenly, wherein the composite fermentation agent is a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus in a ratio of 1:2 in viable bacteria, and the inoculation amount is 0.5-1.0% of the dry weight of the bone gelatin solid waste; fermenting at 45-60°C for 3-4 days to obtain dehydrated solid waste; at this time, the water content of the dehydrated solid waste can be reduced to below 20%.

[0027] Step 2: calcining the dehydrated solid waste at 840-860° C. for 1-1.5 hours, introducing nitrogen for protection during the calcination process, and the oxygen concentration is ≤5%; obtaining a mixture containing calcium oxide and calcium phosphate;

[0028] Step 3: dissolving the mixture in water to form an emulsion with a mass fraction of 25-35%, and then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate in the mixture is 1.2 mol / L and the concentration of hydrochloric acid is 0.3 mol / L; the volume ratio of the emulsion to the mixture of calcium dihydrogen phosphate and hydrochloric acid is 1:(1.3-1.5); controlling the pH to be 6.5-7, and after the reaction is completed, using a filter press to separate the solid and liquid to obtain a wet cake and a mother liquor, and countercurrent washing the wet cake with pure water and a weight ratio of 1:0.8 for 2-3 times to obtain calcium diphosphate, and the mother liquor is reused in the aggregate acid leaching procedure in the bone gelatin production process.

[0029] The experimental methods in the following examples, unless otherwise specified, are all conventional methods and were performed according to the techniques or conditions described in the literature in the field or in accordance with the product instructions. The materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial sources. For example, the bone gelatin solid waste involved in the examples is solid waste generated during the production process of Anhui Fengyuan Gelatin Co., Ltd., and the bone gelatin solid waste in Examples 1-7 all came from the same batch of production solid waste.

[0030] Example 1

[0031] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0032] Step 1: Place 1 ton of bone gelatin solid waste (moisture content 60%; dry basis components: 30% organic matter, CaCO3 / Ca(OH)245%, Ca3(PO4)225%) in a sunroom for 48 hours until the weight is reduced to 571.4 kg, then add 3.2 kg of composite fermentation agent (a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus according to the ratio of viable bacteria 1:2), stir evenly, and ferment at 50°C for 3 days to obtain 487.8 kg of dehydrated solid waste.

[0033] Step 2: placing the dehydrated solid waste in a rotary kiln, introducing nitrogen for protection, and controlling the oxygen concentration to ≤5%; calcining at 850° C. for 1.2 hours to obtain 306 kg of a mixture containing calcium oxide and calcium phosphate. After testing, the mass proportion of calcium oxide is 58.2%, and the balance is calcium phosphate;

[0034] Step 3, dissolving the mixture in 1020 kg of water to form an emulsion, and then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate is 1.2 mol / L, the concentration of hydrochloric acid is 0.3 mol / L, the volume of the mixed solution is 1.4 times the volume of the emulsion, and the pH is controlled to be 6.5. After the reaction is completed, the product is transferred to a filter press for solid-liquid separation to obtain a wet cake and a mother liquor. The pure water and the wet cake are countercurrent washed twice in a weight ratio of 1:0.8 to obtain 126.86 kg of calcium dihydrogen phosphate; the mother liquor is transferred to the aggregate acid leaching procedure as an acid leaching liquid for standby use.

[0035] Example 2

[0036] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0037] Step 1: Place 1 ton of bone gelatin solid waste (moisture content 60%; dry basis components: 30% organic matter, CaCO3 / Ca(OH)245%, Ca3(PO4)225%) in a sunroom for 48 hours until the weight is reduced to 666.67 kg, then add 3.2 kg of composite fermentation agent (a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus according to the ratio of viable bacteria 1:2), stir evenly, and ferment at 50°C for 4 days to obtain 465.5 kg of dehydrated solid waste.

[0038] Step 2: placing the dehydrated solid waste in a rotary kiln, introducing nitrogen for protection, and controlling the oxygen concentration to ≤5%; calcining at 850° C. for 1.2 hours to obtain 301 kg of a mixture containing calcium oxide and calcium phosphate. After testing, the mass proportion of calcium oxide is 57.4%, and the balance is calcium phosphate;

[0039] Step 3, dissolving the mixture in 1003 kg of water to form an emulsion, and then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate is 1.2 mol / L, the concentration of hydrochloric acid is 0.3 mol / L, the volume of the mixed solution is 1.4 times the volume of the emulsion, and the pH is controlled to be 6.5. After the reaction is completed, the product is transferred to a filter press for solid-liquid separation to obtain a wet cake and a mother liquor. The pure water and the wet cake are countercurrent washed twice at a weight ratio of 1:0.8 to obtain 121.24 kg of calcium dihydrogen phosphate; the mother liquor is transferred to the aggregate acid leaching procedure as an acid leaching liquid for standby use.

[0040] Example 3

[0041] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0042] Step 1: Place 1 ton of bone gelatin solid waste (moisture content 60%; dry basis components: 30% organic matter, CaCO3 / Ca(OH)245%, Ca3(PO4)225%) in a sunroom for 48 hours until the weight is reduced to 500 kg, then add 3.2 kg of composite fermentation agent (a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus according to the live bacteria count of 1:2), stir evenly, and ferment at 50°C for 3 days to obtain 425 kg of dehydrated solid waste.

[0043] Step 2: placing the dehydrated solid waste in a rotary kiln, introducing nitrogen for protection, and controlling the oxygen concentration to ≤5%; calcining at 850° C. for 1.2 hours to obtain 315 kg of a mixture containing calcium oxide and calcium phosphate. After testing, the mass proportion of calcium oxide is 60.1%, and the balance is calcium phosphate;

[0044] Step 3, dissolving the mixture in 1050 kg of water to form an emulsion, and then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate is 1.2 mol / L, the concentration of hydrochloric acid is 0.3 mol / L, the volume of the mixed solution is 1.4 times the volume of the emulsion, and the pH is controlled to be 6.5. After the reaction is completed, the product is transferred to a filter press for solid-liquid separation to obtain a wet cake and a mother liquor. The pure water and the wet cake are countercurrent washed twice at a weight ratio of 1:0.8 to obtain 130.56 kg of calcium dihydrogen phosphate; the mother liquor is transferred to the aggregate acid leaching procedure as an acid leaching liquid for standby use.

[0045] Example 4

[0046] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0047] Step 1: Place 1 ton of bone gelatin solid waste (moisture content 60%; dry basis components: 30% organic matter, CaCO3 / Ca(OH)245%, Ca3(PO4)225%) in a sunroom for 48 hours until the weight is reduced to 571.4 kg, then add 3.2 kg of composite fermentation agent (a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus according to the ratio of viable bacteria 1:2), stir evenly, and ferment at 50°C for 3 days to obtain 486.5 kg of dehydrated solid waste.

[0048] Step 2: placing the dehydrated solid waste in a rotary kiln, introducing nitrogen for protection, and controlling the oxygen concentration to ≤5%; calcining at 840°C for 1.5 hours to obtain 308 kg of a mixture containing calcium oxide and calcium phosphate. After testing, the mass proportion of calcium oxide is 58.0%, and the balance is calcium phosphate;

[0049] Step 3, dissolving the mixture in 1027 kg of water to form an emulsion, and then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate is 1.2 mol / L, the concentration of hydrochloric acid is 0.3 mol / L, the volume of the mixed solution is 1.4 times the volume of the emulsion, and the pH is controlled to be 6.5. After the reaction is completed, the product is transferred to a filter press for solid-liquid separation to obtain a wet cake and a mother liquor. The pure water and the wet cake are countercurrent washed twice in a weight ratio of 1:0.8 to obtain 125.25 kg of calcium dihydrogen phosphate; the mother liquor is transferred to the aggregate acid leaching procedure as an acid leaching liquid for standby use.

[0050] Example 5

[0051] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0052] Step 1: Place 1 ton of bone gelatin solid waste (moisture content 60%; dry basis components: 30% organic matter, CaCO3 / Ca(OH)245%, Ca3(PO4)225%) in a sunroom for 48 hours until the weight is reduced to 571.4 kg, then add 3.2 kg of composite fermentation agent (a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus according to the ratio of viable bacteria 1:2), stir evenly, and ferment at 50°C for 3 days to obtain 485.8 kg of dehydrated solid waste.

[0053] Step 2: placing the dehydrated solid waste in a rotary kiln, introducing nitrogen for protection, and controlling the oxygen concentration to ≤5%; calcining at 860°C for 1 hour to obtain 302 kg of a mixture containing calcium oxide and calcium phosphate. After testing, the mass proportion of calcium oxide is 58.1%, and the balance is calcium phosphate;

[0054] Step 3, dissolving the mixture in 1007 kg of water to form an emulsion, and then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate is 1.2 mol / L, the concentration of hydrochloric acid is 0.3 mol / L, the volume of the mixed solution is 1.4 times the volume of the emulsion, and the pH is controlled to be 6.5. After the reaction is completed, the product is transferred to a filter press for solid-liquid separation to obtain a wet cake and a mother liquor. The pure water and the wet cake are countercurrent washed twice at a weight ratio of 1:0.8 to obtain 127.25 kg of calcium dihydrogen phosphate; the mother liquor is transferred to the aggregate acid leaching procedure as an acid leaching liquid for standby use.

[0055] Example 6

[0056] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0057] Step 1: Place 1 ton of bone gelatin solid waste (moisture content 60%; dry basis components: 30% organic matter, CaCO3 / Ca(OH)245%, Ca3(PO4)225%) in a sunroom for 48 hours until the weight is reduced to 571 kg, then add 2 kg of composite fermentation agent (a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus according to the ratio of viable bacteria 1:2), stir evenly, and ferment at 50°C for 3 days to obtain 495.5 kg of dehydrated solid waste.

[0058] Step 2: placing the dehydrated solid waste in a rotary kiln, introducing nitrogen for protection, and controlling the oxygen concentration to ≤5%; calcining at 850° C. for 1.2 hours to obtain 299 kg of a mixture containing calcium oxide and calcium phosphate. After testing, the mass proportion of calcium oxide is 57.1%, and the balance is calcium phosphate;

[0059] Step 3, dissolving the mixture in 996 kg of water to form an emulsion, and then adding a mixture of calcium dihydrogen phosphate-hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate is 1.2 mol / L, the concentration of hydrochloric acid is 0.3 mol / L, the volume of the mixed solution is 1.4 times the volume of the emulsion, and the pH is controlled to be 6.5. After the reaction is completed, the product is transferred to a filter press for solid-liquid separation to obtain a wet cake and a mother liquor. The pure water and the wet cake are countercurrent washed twice at a weight ratio of 1:0.8 to obtain 122.52 kg of calcium dihydrogen phosphate; the mother liquor is transferred to the aggregate acid leaching procedure as an acid leaching liquid for standby use.

[0060] Example 7

[0061] This embodiment discloses a method for treating bone gelatin solid waste, comprising the following steps:

[0062] Step 1: Place 1 ton of bone gelatin solid waste (moisture content 60%; dry basis components: 30% organic matter, CaCO3 / Ca(OH)245%, Ca3(PO4)225%) in a sunroom for 48 hours until the weight is reduced to 571.4 kg, then add 4 kg of composite fermentation agent (a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus according to the ratio of viable bacteria 1:2), stir evenly, and ferment at 50°C for 3 days to obtain 465.89 kg of dehydrated solid waste.

[0063] Step 2: placing the dehydrated solid waste in a rotary kiln, introducing nitrogen for protection, and controlling the oxygen concentration to ≤5%; calcining at 850°C for 1.2 hours to obtain 318 kg of a mixture containing calcium oxide and calcium phosphate. After testing, the mass proportion of calcium oxide is 55.2%, and the balance is calcium phosphate;

[0064] Step 3, dissolving the mixture in 1060 kg of water to form an emulsion, and then adding a mixture of calcium dihydrogen phosphate-hydrochloric acid, wherein the concentration of calcium dihydrogen phosphate is 1.2 mol / L, the concentration of hydrochloric acid is 0.3 mol / L, the volume of the mixed solution is 1.4 times the volume of the emulsion, and the pH is controlled to be 6.5. After the reaction is completed, the product is transferred to a filter press for solid-liquid separation to obtain a wet cake and a mother liquor. The pure water and the wet cake are countercurrent washed twice at a weight ratio of 1:0.8 to obtain 130.14 kg of calcium dihydrogen phosphate; the mother liquor is transferred to the aggregate acid leaching procedure as an acid leaching liquid for standby use.

[0065] The mass of calcium hydrogen phosphate and calcium oxide obtained from the treatment of each ton of bone gelatin solid waste in Examples 1-5 is listed in Table 1. Table 1 is as follows:

[0066] Table 1

[0067]

[0068] Analyzing the data in Table 1, it can be seen that in Examples 1-7, after being treated by the treatment method of the present invention, each ton of bone gelatin solid waste can stably produce more than 120kg of calcium hydrogen phosphate, while reducing the processing costs of the bone gelatin solid waste entrusted to a third party. For example, taking Anhui Fengyuan Gelatin Co., Ltd. as an example, the company produces approximately 130 tons of bone gelatin solid waste per day. The purchase price of calcium hydrogen phosphate is 2,800 yuan / ton, and the purchase price of calcium oxide is 600 yuan / ton. The cost required for the method of treating bone gelatin solid waste of the present invention is 212 yuan / ton. Taking the production of 125kg of calcium hydrogen phosphate and 175kg of calcium oxide per ton of bone gelatin solid waste as an example, the cost saved per day is: 130*0.125*2880+130*0.175*600+130*65-212*130=41,340 yuan.

[0069] In summary, the method for treating bone gelatin solid waste of the present invention can transform bone gelatin solid waste into treasure, bring economic benefits to manufacturers, and realize commercial value.

[0070] The above describes in detail several embodiments of the present invention. However, the above contents are only preferred embodiments of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A method for treating bone gelatin solid waste, characterized in that: The steps include: Step 1: drying bone gelatin solid waste with an initial moisture content of 50-70% in the sun until the moisture content is 20-40%, adding a composite fermentation agent, stirring evenly, and fermenting at 45-60° C. for 3-4 days to obtain dehydrated solid waste; Step 2: calcining the dehydrated solid waste at 840-860° C. for 1-1.5 hours to obtain a mixture containing calcium oxide and calcium phosphate; Step 3: dissolving the mixture in water to form an emulsion, then adding a mixture of calcium dihydrogen phosphate and hydrochloric acid, controlling the pH to 6.5-7, and performing solid-liquid separation after the reaction is completed to obtain calcium dihydrogen phosphate.

2. The method for treating bone gelatin solid waste according to claim 1, wherein In step 1, the composite fermentation agent is a mixed agent obtained by compounding Bacillus subtilis and Streptomyces griseus in a ratio of 1:2 in terms of viable bacteria count.

3. The method for treating bone gelatin solid waste according to claim 1, wherein In step 1, the inoculation amount of the composite fermentation bacteria agent is 0.5-1.0% of the dry weight of the bone gelatin solid waste.

4. The method for treating bone gelatin solid waste according to claim 1, wherein In step 1 and step 2, nitrogen is introduced during the calcination process for protection, and the oxygen concentration is ≤5%.

5. The method for treating bone gelatin solid waste according to claim 1, wherein In step three, the mass fraction of the emulsion is 25-35%.

6. The method for treating bone gelatin solid waste according to claim 5, wherein: In step three, the concentration of calcium dihydrogen phosphate in the calcium dihydrogen phosphate-hydrochloric acid mixture is 1.2 mol / L, and the concentration of hydrochloric acid is 0.3 mol / L.

7. The method for treating bone gelatin solid waste according to claim 6, wherein: In step 3, the volume ratio of the emulsion to the mixed solution of calcium dihydrogen phosphate-hydrochloric acid is 1:(1.3-1.5).

8. The method for treating bone gelatin solid waste according to claim 1, wherein: In step three, a filter press is used to perform solid-liquid separation to obtain a wet cake and a mother liquor, and the wet cake is washed to obtain calcium hydrogen phosphate.

9. The method for treating bone gelatin solid waste according to claim 8, wherein: The washing method is: countercurrent washing is performed with pure water and wet cake in a weight ratio of 1:0.8, and the washing times are 2-3 times.

10. The method for treating bone gelatin solid waste according to claim 8, characterized in that: The mother liquor is reused in the aggregate acid leaching process during the production of bone gelatin.

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