An oil removal filter material, a preparation method and application thereof

Abstract

The embodiment of the application discloses a kind of oil removal filter material and its preparation method and application.A kind of preparation method of oil removal filter material, with waste glass particles and neodymium iron boron waste material particles as raw material, in the presence of foaming agent, foaming promoter and silane coupling agent, after drying, sintering foaming is carried out, natural cooling to normal temperature, breakage, obtain the oil removal filter material.The oil removal filter material provided by the application has better demulsification and oil removal effect, improves the water quality, and is not prone to blockage, and the water flow rate of 10-20BV / h can complete backwashing, while using waste glass, neodymium iron boron waste material as raw material, has the characteristics of low cost, economic and environmental protection, meets the concept of energy saving and environmental protection in today's society, and has wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, specifically to an oil removal filter material, its preparation method, and its application. Background Technology

[0002] Oily wastewater mainly originates from the petrochemical, coal chemical, machinery processing, and textile industries, and its oil content is highly emulsified and difficult to biodegrade. Semi-coke wastewater is primarily generated in the wet quenching unit of semi-coke cooling and the residual circulating ammonia water unit of coal gas purification. The pretreatment section for semi-coke wastewater is severely affected by emulsified oil clogging, significantly impacting effluent quality and project progress. Effective pretreatment technology to remove emulsified oil is crucial for achieving resource recovery and efficient treatment of semi-coke wastewater.

[0003] Emulsified oil has a particle size of 0.1-10 μm and can form a relatively stable dispersion with water. The oil-water interface is the reason for the stable existence of emulsified oil, and disrupting the oil-water interface film is the key to oil removal. Traditional pretreatment processes use quartz sand as filter media, which has a small specific surface area, low porosity, and disordered distribution and coupling of hydroxyl groups on the surface of quartz sand, resulting in low activity and severe caking of the filter media during use.

[0004] Seyyedali Mirshahghassemi et al. synthesized PVP-coated magnetic Fe3O4 nanoparticles for adsorbing and removing oil from wastewater. They used a high-gradient magnetic separator composed of two NdFeB magnets to separate the oil-adsorbed Fe3O4 nanoparticles, achieving an oil removal rate of up to 95%. However, this process is cumbersome. First, the magnetic Fe3O4 needs to be added to the water sample and stirred for about 1 hour. Then, a peristaltic pump is used to extract the water sample. The water sample passes through the magnetic separator, causing the magnetic Fe3O4 in the sample to be adsorbed onto steel wool in the middle of the separator. The biggest drawback is that the steel wool needs to be removed and cleaned, which is quite difficult.

[0005] Patent CN 104998466 B proposes a lightweight filter medium, foam glass, for water treatment. By increasing the specific surface area and porosity of the glass filter media, it can effectively filter and retain suspended solids during water treatment and has a good turbidity removal effect. However, it has a poor demulsification and oil removal effect when treating oily wastewater. Summary of the Invention

[0006] Therefore, this invention provides an oil removal filter material, its preparation method, and its application. This oil removal filter material has a better demulsification and oil removal effect, improves the quality of effluent, and is not prone to clogging. Backwashing can be completed using clean water with a flow rate of 10-20 BV / h. At the same time, it uses waste glass and NdFeB waste as raw materials, which has the characteristics of low cost, economy, and environmental protection, conforms to the concept of energy conservation and environmental protection in today's society, and has broad application prospects.

[0007] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0008] According to a first aspect of the present invention, the present invention provides a method for preparing an oil-removing filter material, which uses waste glass particles and NdFeB waste particles as raw materials, and in the presence of a foaming agent, a foaming accelerator and a silane coupling agent, after drying, sintering and foaming, cooling to room temperature, and crushing to obtain the oil-removing filter material.

[0009] Oil droplets in oil-in-water (O / W) oily wastewater are mostly negatively charged and can be adsorbed by positively charged magnetic particles. The oil removal filter media of this invention uses inorganic crushed glass as a carrier and neodymium iron boron permanent magnets as the core material. The high magnetic properties of the neodymium iron boron permanent magnets result in a strong attraction between the magnets and the oil droplets, causing the magnetic particles to disrupt the stable interface of the emulsified oil in the aqueous phase. This allows the oil droplets to demulsify and coalesce on the magnetic particles, achieving oil-water separation.

[0010] Furthermore, by weight, the waste glass particles are 30-70 parts, the neodymium iron boron waste particles are 5-15 parts, the foaming agent is 0.5-13 parts, the foaming accelerator is 1-10 parts, and the silane coupling agent is 1-10 parts.

[0011] Furthermore, the foaming agent is selected from one or more of carbon black, silicon carbide, calcium carbonate, dolomite, phlogopite, graphite, and manganese dioxide.

[0012] Furthermore, the foaming accelerator is selected from one or more of sodium nitrate, soda ash, sodium fluorosilicate, sodium carbonate, and ethylenediamine salt.

[0013] Furthermore, the silane coupling agent is selected from one or more of vinylsilane, aminosilane, and methacryloxysilane.

[0014] Furthermore, the drying conditions are: temperature 150-200℃, time 1-3h;

[0015] The conditions for sintering and foaming are as follows: hold at 500-620℃ for 30-60 minutes, then increase to 1000-1500℃ at 20-30℃ / min for foaming, the foaming time is 0.5-2 hours, and after completion, hold at 1050-1110℃ for 3-5 hours.

[0016] The particle size of the oil removal filter media is 30-60 mm.

[0017] Furthermore, the method for preparing the waste glass particles is as follows: the waste glass is subjected to acid washing and alkali washing in sequence, and then crushed to obtain waste glass particles with a particle size of 1-10mm.

[0018] The pickling process includes: placing the waste glass in 1-3 mol / L hydrochloric acid, immersing it at 20-40℃ for 1-3 hours, and then rinsing it with water;

[0019] The alkaline washing process includes: placing the acid-washed waste glass in an alkaline soapy water solution with a concentration of 0.2%-0.5% and soaking it at 20-40℃ for 1-3 hours; washing it with water and then drying it at 105-110℃ for 2-3 hours.

[0020] Waste glass is an inorganic non-metallic material containing SiO2, sodium silicate, calcium silicate, etc., and its main component is silicate complex salt, which is an amorphous solid with an irregular structure. After acid washing and alkali washing, inorganic salts, minerals, metal fragments, fats and proteins can be removed from the surface of waste glass, which is beneficial to subsequent processing and the controllability of the final product.

[0021] Furthermore, the method for preparing the NdFeB waste particles is as follows: the NdFeB waste is subjected to acid washing and alkali washing in sequence, and then crushed to obtain NdFeB waste particles with a particle size of 1-10mm.

[0022] The pickling process includes: placing the NdFeB waste in 0.5-2 mol / L hydrochloric acid, soaking it at 20-40℃ for 1-2 hours, and then washing it with water;

[0023] The alkaline washing process includes: placing the acid-washed NdFeB waste in 1-3 mol / L sodium hydroxide solution, soaking it at 60-70℃ for 1-3 hours, washing it with water, and then drying it at 105-110℃ for 2-3 hours.

[0024] Neodymium iron boron (NdFeB) waste (permanent magnets) is rich in rare earth elements such as Nd, Pr, and Dy, with a rare earth element content of approximately 30% (of which neodymium accounts for about 90%, and the rest are praseodymium, gadolinium, terbium, dysprosium, holmium, etc.), an iron content of about 65%, a boron content of about 1%, and trace elements such as aluminum and copper. After acid and alkali washing, the NdFeB waste can be cleaned of metal debris, surface oxides, fats, and proteins from its surface, which is beneficial for subsequent processing and the controllability of the final product.

[0025] According to a second aspect of the present invention, the present invention provides an oil removal filter media made by the method described in any of the preceding claims.

[0026] According to a third aspect of the present invention, the present invention provides the application of the oil-removing filter media as described above in the removal of emulsified oil from water.

[0027] The embodiments of the present invention have the following advantages:

[0028] The oil-removing filter media of this invention uses waste glass, neodymium iron boron waste, foaming agent, foaming accelerator, and silane coupling agent as raw materials. It is manufactured into foam glass oil-removing filter media through a low-temperature sintering-high-temperature foaming method. It possesses properties such as strong magnetism, high porosity, large specific surface area, and lightweight. It exhibits excellent oil adsorption and demulsification capabilities, causing oil droplets to rapidly coalesce. During use, it provides fast filtration speed and good oil removal effect. Furthermore, the filter media expansion rate during backwashing is approximately 50%, facilitating rapid and effective backwashing. Attached Figure Description

[0029] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0030] Figure 1 This is a scanning electron microscope image of the oil removal filter media of Embodiment 1 of the present invention. Detailed Implementation

[0031] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] The preparation method of waste glass particles, as described below, includes the following steps:

[0033] (1) Pickling: The waste glass (mainly scraps from glass manufacturers and household waste) is placed in a 2mol / L hydrochloric acid cleaning tank for rinsing and soaking for 1 hour. After rinsing, the glass is taken out and rinsed with a high-pressure water gun to remove impurities such as hydrochloric acid from the glass surface.

[0034] (2) Alkaline washing: Immerse the glass after cleaning in step (1) in 0.5% alkaline soapy water for 1 hour, take out the glass and rinse it with a high-pressure water gun until no foam is produced. Dry the glass after washing at 105℃ for 2 hours.

[0035] (3) Crushing; the glass dried in step (2) is crushed to obtain waste glass particles with a particle size of 1-10mm, which are then stored for later use.

[0036] The preparation method of NdFeB waste granules includes the following steps:

[0037] (1) Pickling: Place the NdFeB waste (mainly from the scraps in the production and processing process) into a cleaning tank with 2 mol / L hydrochloric acid, rinse the NdFeB waste, soak for 1 hour, and then remove the coating on the surface of the waste.

[0038] (2) Alkali washing: The waste material after acid washing in step (1) is immersed in a 65℃ hot alkaline bath (2mol / L sodium hydroxide) for 2 hours, rinsed with a high-pressure water gun, and the cleaned NdFeB waste material is dried at 105℃ for 2 hours.

[0039] (3) Crushing; The NdFeB waste material dried in step (2) is crushed to obtain NdFeB waste material particles with a particle size of 1-10mm. The particles are sealed and stored to prevent the magnetism from weakening due to prolonged contact with moisture and oxygen in the air.

[0040] Example 1

[0041] This embodiment provides an oil removal filter material, the preparation method of which is as follows:

[0042] Take 30 parts of waste glass particles, 8 parts of NdFeB waste particles, 1 part of a composite foaming agent composed of manganese dioxide, SiC, and Si3N4 in a mass ratio of 2:4:4, 1 part of sodium nitrate, and 2 parts of vinyl silane. Mix the above materials evenly, spread the resulting mixed powder evenly in a square mold (ceramic fiber paper), dry at 150℃ for 1 hour, and then directly put it into a muffle furnace that has been preheated to a sintering temperature of 550℃ for sintering for 30 minutes. Then, increase the temperature to 1100℃ at 20℃ / min for foaming for 0.5 hours. After completion, keep it at 1050℃ for 3 hours, and finally cool it naturally to room temperature and crush it to obtain an oil removal filter material with a particle size of 30-40mm.

[0043] Example 2

[0044] This embodiment provides an oil removal filter material, the preparation method of which is as follows:

[0045] Take 30 parts of waste glass particles, 5 parts of NdFeB waste particles, 2 parts of composite foaming agent composed of CaCO3 and SiC in a mass ratio of 1:1, 2 parts of soda ash, and 1 part of aminosilane. Mix the above materials evenly, spread the resulting mixed powder evenly in a square mold (ceramic fiber paper), dry at 200℃ for 2 hours, and then directly put it into a muffle furnace that has been preheated to a sintering temperature of 580℃ for sintering for 30 minutes. Then, increase the temperature to 1300℃ at 25℃ / min for foaming for 1 hour. After completion, keep it at 1050℃ for 5 hours, and finally cool it naturally to room temperature and crush it to obtain an oil removal filter material with a particle size of 50-60mm.

[0046] Example 3

[0047] This embodiment provides an oil removal filter material, the preparation method of which is as follows:

[0048] Take 50 parts of waste glass particles, 8 parts of NdFeB waste particles, 5 parts of composite foaming agent composed of phlogopite and graphite in a mass ratio of 7:3, 2 parts of ethylenediamine salt, and 1 part of methacryloyloxysilane. Mix the above materials evenly, spread the resulting mixed powder evenly in a square mold (ceramic fiber paper), dry at 180℃ for 3 hours, and then directly put it into a muffle furnace that has been preheated to a sintering temperature of 600℃ for sintering for 60 minutes. Then, increase the temperature to 1500℃ at 30℃ / min for foaming for 1 hour. After completion, keep it at 1110℃ for 5 hours, and finally cool it naturally to room temperature and crush it to obtain an oil removal filter material with a particle size of 40-50mm.

[0049] Comparative Example 1

[0050] This comparative example provides an oil removal filter material, the preparation method of which is as follows:

[0051] Take 30 parts of waste glass particles, 1 part of a composite foaming agent composed of manganese dioxide, SiC, and Si3N4 in a mass ratio of 2:4:4, 1 part of sodium nitrate, and 2 parts of vinyl silane. Mix the above materials evenly, spread the resulting mixed powder evenly in a self-made square mold (ceramic fiber paper), dry at 150℃ for 1 hour, and then directly put it into a muffle furnace that has been preheated to a sintering temperature of 550℃ for sintering for 30 minutes. Then, increase the temperature to 1100℃ at a rate of 20℃ / min for foaming for 0.5 hours. After completion, keep it at 1050℃ for 3 hours, and finally cool it naturally to room temperature and crush it to obtain glass filter material with a particle size of 30-40mm.

[0052] Test Example 1

[0053] The oil removal filter media of Example 1 was subjected to scanning electron microscopy (SEM) experiments, and the SEM images are shown below. Figure 1 The electron microscope images show obvious undulations and texture features, reflecting that the glass filter material has a large specific surface area, is lightweight, and has many bright areas, proving that the filter material is uniform.

[0054] The performance of the oil removal filter media in Examples 1-3 was tested, and the results are shown in Table 1 below.

[0055] Table 1

[0056]

[0057]

[0058] Test Example 2

[0059] In Examples 1-3 and Comparative Example 1, the oil removal filter media and a commercially available glass filter media were respectively packed into columns. The feed liquid (containing a large amount of phenolic substances and emulsified oil) of a certain factory before semi-coke pretreatment was fed into the column at a flow rate of 5 BV / h using a bottom-in, top-out method. The effluent was collected, allowed to stand for 2 hours to separate into layers, and the lower layer of the feed liquid was taken for oil content analysis. The results are shown in Table 2 below.

[0060] Table 2. Data from the first round of comparative oil removal experiments.

[0061]

[0062] After the adsorption column had run for 1500 BV, it was backwashed with clean water at a flow rate of 15 BV / h for 30 minutes. Following backwashing, a second round of pretreatment for oil removal was conducted. The backwashing and second-round pretreatment data are shown in Tables 3-4 below.

[0063] Table 3 Backwashing Experiment Data

[0064]

[0065]

[0066] Table 4. Data from the second round of comparative oil removal experiments.

[0067]

[0068] The results show that the oil removal filter media provided in this embodiment of the invention can significantly reduce the oil content and significantly improve the quality of treated water when conducting pretreatment oil removal experiments on oily wastewater. It can also operate stably and for a long time. In addition, it has high backwashing efficiency and can be reused multiple times.

[0069] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. The use of an oil removal filter material for removing emulsified oil in a water body, characterized in that, The preparation method of the oil removal filter material comprises the following steps: taking waste glass particles and neodymium-iron-boron waste particles as raw materials, in the presence of a foaming agent, a foaming promoter and a silane coupling agent, drying, sintering and foaming, cooling to room temperature, and crushing to obtain the oil removal filter material; the waste glass particles are 30-70 parts, the neodymium-iron-boron waste particles are 5-15 parts, the foaming agent is 0.5-13 parts, the foaming promoter is 1-10 parts, and the silane coupling agent is 1-10 parts; the sintering and foaming conditions are as follows: sintering at 500-620 DEG C for 30-60 min, then increasing to 1000-1500 DEG C at a rate of 20-30 DEG C / min, foaming for 0.5-2 h, and then keeping the temperature at 1050-1110 DEG C for 3-5 h; and the particle size of the oil removal filter material is 30-60 mm. The foaming agent is selected from one or more of carbon black, silicon carbide, calcium carbonate, dolomite, phlogopite, graphite and manganese dioxide. The foaming promoter is selected from one or more of sodium nitrate, soda ash, sodium fluosilicate and ethylenediamine salt. The silane coupling agent is selected from one or more of vinyl silane, amino silane and methacryloyloxy silane.

2. The application according to claim 1, wherein, The drying conditions are as follows: a temperature of 150-200 DEG C and a time of 1-3 h.

3. Use according to claim 1, characterized in that, The preparation method of the waste glass particles comprises the following steps: sequentially subjecting waste glass to acid washing and alkali washing, and crushing to obtain waste glass particles with a particle size of 1-10 mm. The acid washing process comprises the following steps: placing the waste glass in 1-3 mol / L hydrochloric acid, soaking at 20-40 DEG C for 1-3 h, and washing with water. The alkali washing process comprises the following steps: placing the acid-washed waste glass in 0.2%-0.5% alkali soap water, soaking at 20-40 DEG C for 1-3 h, washing with water, and drying at 105-110 DEG C for 2-3 h.

4. Use according to claim 1, characterized in that, The preparation method of the neodymium-iron-boron waste particles comprises the following steps: sequentially subjecting neodymium-iron-boron waste to acid washing and alkali washing, and crushing to obtain neodymium-iron-boron waste particles with a particle size of 1-10 mm. The acid washing process comprises the following steps: placing the neodymium-iron-boron waste in 0.5-2 mol / L hydrochloric acid, soaking at 20-40 DEG C for 1-2 h, and washing with water. The alkali washing process comprises the following steps: placing the acid-washed neodymium-iron-boron waste in 1-3 mol / L sodium hydroxide, soaking at 60-70 DEG C for 1-3 h, washing with water, and drying at 105-110 DEG C for 2-3 h.

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