Comprehensive utilization technology of zeolite

1, since the current utilization art process flow artificial zeolite having a high purity, good and stable performance, etc., have been widely used in many aspects of the petroleum industry, atomic energy industry, electronic industry, polymer chemical industry and the like, but synthetic molecular sieves (artificial Synthetic zeolites are expensive and expensive. If natural zeolite is used instead of some synthetic molecular sieves in related fields, it has the advantages of low cost, good acid resistance and good thermal stability. However, due to the weakness of natural zeolite purity, it is difficult to utilize natural zeolite as a molecular sieve and a catalyst. The ore- selected zeolite rock not only improves the grade of the zeolite, but also makes the quality and performance more stable and improves the use value. Therefore, it is necessary to conduct ore dressing and purification of low-grade zeolite rock.
(1) Selenium beneficiation method A large amount of research has been conducted at home and abroad in order to seek an effective beneficiation method of zeolite. To summarize these research results, there are mainly the following methods: 1 using re-election equipment suitable for processing fine materials (such as shaker), and re-election equipment for centrifugal field strengthening. 2 The flotation is used to treat the fine ore with fine particle size, and the selectivity of the mineral can be improved by adjusting the flotation agent. In the flotation, the pH value of the flotation pulp should be strictly controlled. Flotation is the most promising beneficiation method for zeolites. 3 The selective flocculation separation method is adopted. The domestic research on mordenite has achieved good results.
Example of zeolite flotation method: The clinoptilolite is sorted by a combined process. Ore mineral composition clinoptilolite addition, the main montmorillonite, quartz and a small amount of feldspar, apatite, biotite and the like. The flotation process is shown in Figure 1. [next]

In the research of zeolite beneficiation process, many countries are working, but they are very difficult, mainly because the crystalline particles of zeolite are very fine and the mineralization properties of symbiotic minerals (such as specific gravity, floatability, electrical conductivity, magnetic properties) Etc.) The difference is small. According to the current research results, the following methods can be used: flotation method, selective flocculation sorting method, re-election, electromagnetic method, among which flotation method is the most studied and most promising beneficiation method. .
Most of the world's natural zeolite products are produced dry. There are also wet selections.
The production method adopted in Japan is a process such as coarse crushing, drying, fine pulverization, grading, and packaging.
In order to determine the applicability of the beneficiation technology in terms of increasing the zeolite content of the ore, the United States has conducted the usual classification and concentration as well as the shaker selection and interference settling processes. [next]
At present, the zeolites sold on the world market do not seem to have been sorted by the concentrator, and generally only after being crushed and sieved, the zeolite minerals have a certain particle size.
(2) Deep processing of zeolite Since the discovery of the first natural zeolite mineral producing area in China, various relevant departments have done a lot of research and promotion work on the deep processing and application of natural zeolite. Among them are zeolite-filled cement and its products, catalysts, desiccants, purifying agents, paper fillers and artificial leather fillers, soap additives, toothpaste abrasives, zeolite ammonium bicarbonate, poultry feed additives and deodorants. product. Examples are as follows:
A. Steel slag zeolite (less clinker) Cement Steel slag zeolite cement was successfully developed for the first time in China. It can use steelmaking waste residue, use less or no cement clinker, save energy and handle three wastes. Steel slag zeolite cement is a better cementitious material. The best ratio is: steel slag 67~71%, zeolite 25~30%, gypsum 6~8%. It is made by grinding and mixing. The production of steel slag zeolite requires high grade of zeolite rock (content of zeolite >50%, absorption value of 110mmol/100g or more), stable quality and uniform mineralization. The steel slag zeolite cement meets the GB-1344-77-325 standard, and its production process flow is shown in Figure 2.

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B, lime zeolite cement (also known as clinker-free cement)
Lime zeolite cement is a hydraulic cementitious material which is prepared by calcining zeolite rock, lime and gypsum without raw material, and mixing it in an appropriate proportion and directly grinding. Its strength can reach the cement standard of 300~400, and has Acid and alkali resistant properties.
The zeolite content in the zeolite rock is required to be greater than 50%; the calcium oxide absorption value is greater than 150 mg/g; the active ingredient (soluble silicon and soluble aluminum ) content is greater than 15%; the slaked lime sand strength requirement is: tensile strength: 7 days 1 MPa, 28 days 1.5MPa; compressive strength: 7 days 9.8 MPa, 28 days 19.6 MPa; impurities containing montmorillonite should not exceed 10%. In addition, the quality of lime and gypsum also has an effect on the strength of the cement. Lime is required to be a massive ore of >70% calcium, and gypsum requires SO ₃ >35%.
The proportion of ingredients is: zeolite 65~70%, lime 23~27%, gypsum 3~8%.
The production process is shown in Figure 3.
The mortars of No. 50, No. 75 and No. 100 prepared with this kind of cement meet the performance requirements of construction mortar, and have the advantages of no delamination, no precipitation, and good compatibility. Under the condition of damp heat curing, the strength of the product can be greatly increased and the durability is improved. It is a new type of cementing material in the building, which has the characteristics of stable quality and low cost. [next]

Major enterprises: Mudanjiang City, Heilongjiang Province and related manufacturers in Fuxin City, Liaoning Province.
C. Paper filler Natural zeolite powder is used as a filler and coating agent for papermaking. The clinoptilolite is ground by a wet or dry classification cyclone to obtain a product having a particle size of 10 mm or less (see Fig. 4), and has a wear index of <3% and a whiteness of about 80%. This filler is made of kraft paper with a clay filler compared to more opaque, easy cutline, difficult ink stains, it may also be made lightweight papers.
The main domestic experimental and research areas are Nenjiang County of Heilongjiang Province, Lishui District of Zhejiang Province, and Lingxi County of Guangxi Zhuang Autonomous Region. [next]

(3) General acid treatment process of zeolite The general treatment method of natural zeolite includes pulverizing the ore to a certain particle size, then immersing it in hydrochloric acid or sulfuric acid solution for a certain period of time, and then boiling the neutralized ore sample in water. After a certain period of time, the product is finally dried and roasted. The zeolite thus treated can improve its adsorption performance. The specific process is as follows: [next]
1 crushing: crush the ore to 5~80 mesh. If the particles are larger than 5 mesh, the acid can only impregnate the surface of the crystal and it is difficult to soak the internal structure of the crystal, so that the impurities or soluble substances in the internal structure pores cannot be removed, which affects the adsorption performance. On the contrary, if the particles are smaller than 80 mesh, on the one hand, it is not suitable for practical use, and on the other hand, the particles are too small to be blown off to affect the yield.
2 Acid treatment: It can be treated with hydrochloric acid or sulfuric acid at a concentration of 4 to 10%. The acid concentration is too low, and the effect of dissolving impurities and solubles is poor; if the acid concentration is too high, it may cause difficulty in neutralization and inconvenience in operation. The immersion treatment time is preferably 10 to 20 hours.
3 Neutralization and water boiling: The acid-treated zeolite is neutralized with sodium carbonate (or potassium carbonate), caustic soda (or caustic potash), and the like. After neutralization and washing, boil for 30 to 60 minutes with water.
4 Drying and calcination: The zeolite treated as described above is dried prior to calcination. If it is directly calcined without drying, the rapid evaporation of water remaining in the inner pores of the crystal and the rapid high temperature treatment will locally destroy the zeolite structure, thereby affecting its adsorption performance. Practice has shown that the calcination temperature after drying is preferably from 350 to 580 °C.
5 Re-pulverization: The calcined zeolite is further pulverized to 30 to 50 mesh to obtain an active zeolite having an adsorption property even superior to that of activated carbon.
The following table shows the adsorption effect of acid-treated active zeolite on NH ₃ . [next]

(4) Modified treatment method of zeolite The natural zeolite has been subjected to appropriate chemical modification treatment, which can make the original ion exchange capacity stronger, and some zeolites with poor adsorption performance become a new type of adsorption capacity. Zeolite. The main modifications are as follows.
1P type zeolite: P type zeolite can be formed by treating natural zeolite with NaOH solution. For example, 3 g of 10 to 200 mesh natural clinoptilolite is added to 10 ml of 5 mol/L NaOH solution and heated at 95 ± 5 ° C for 70 hours to obtain P. Zeolite. The amount of adsorption of C _d Cl ₂ by the modified P-type zeolite is greatly increased. However, when alkali treatment, the NaOH concentration should not be too high, otherwise the zeolite structure will be destroyed. [next]
Type 2H zeolite: The natural mordenite is treated with a dilute mineral acid (HCl, H ₂ SO ₄ , HNO ₃ , HClO _{4 ,} etc.) to have an H+ exchange rate of at least 20%. After molding, it is dried at 90~110 °C, and finally heated and activated at 350~600 °C. Type H zeolite has a high adsorption rate and a cation exchange capacity.
â‘¢Cu zeolite: when removing the copper zeolite with Cu ²⁺ exchange system, often due to the H + zeolite containing Cu ²⁺ exchange hindered. Since the zeolite is immersed in concentrated ammonia water prior to exchange, NH ₄ ^{+ is} first replaced by H + in the zeolite. The preparation of the Cu type zeolite is mainly to treat the zeolite with copper nitrate (optimal), copper sulfate or copper chloride, and at the same time, the exchange rate of Cu is 50% or more. The exchanged zeolite can be mixed with water and activated at an appropriate temperature for use. A small amount of aluminum stearate, graphite or the like may be used as a binder, or a carrier such as aluminum chloride or diatomaceous earth may be used.
4Na type zeolite: The natural mordenite is treated with an excess of sodium salt solution (NaCl, Na ₂ SO ₄ , NaNO _{3 ,} etc.) to make the Na ⁺ exchange rate at least 75%, and after drying, it is dried at 90-110 ° C, and finally It is made by heating and activation at 350~600 °C. The Na-type zeolite will greatly increase its adsorption capacity for gas, even larger than that of the synthesized 5A molecular sieve.
5NH4 type zeolite: The natural zeolite was treated with a 2 mol/L NH4Cl solution, and then a 2 mol/L KCl solution was used as a detergent to achieve a cation exchange capacity of 145 mN/100 g.
Type 6Ca zeolite: The natural zeolite was treated with 2N CaCl ₂ solution, and then 2 mol of NH ₄ Cl solution was used as a detergent, and the cation exchange capacity was up to 59 mN/100 g.
7 faujasite: At present, a large part of the zeolite minerals discovered in China is clinoptilolite, and its fatal weakness is small specific surface area and small pore size. For example, the modification of clinoptilolite to faujasite can be widely used in the fields of chemical industry and oil refining, and greatly enhances the use value of such rich and inexpensive minerals. [next]
The modification of the clinoptilolite to faujasite has changed its mineral structure from monoclinic to cubic, and the lattice parameters and the ratio of silicon to aluminum have changed greatly. The mechanism of this modification process is actually The process of recrystallization of zeolite is the process of re-formation of the silicate cation skeleton. Clinoptilolite in the aqueous solution of NaOH and NaCl, the solid phase crystalline clinoptilolite softens, depolymerizes by (OH) ^- catalysis in the medium to form zeolite structural unit, and the crystal nucleus is further ordered to form eight sides. Zeolite crystals. The reaction mechanism is as follows:
Na ₆ •Al ₆ •Si ₃ 0 ₇₂ •24H ₂ O ^NaOH+NaCl 3[Na ₂ O•Al ₂ O ₃ •4SiO ₂ •6H ₂ O]+18SiO ₂ +6H ₂ O
The process flow for preparing faujasite is shown in Figure 5. The conditions of the modification are relatively strict. When the concentration of the alkali solution in the reaction is low (<2mol/L), the P-type zeolite (calcium cross zeolite type) is easily formed; when the concentration of the alkali solution in the reaction is too high (>4 mol/L), Then, hydroxysodalite is produced. Therefore, the alkali concentration of the reaction, the amount of the auxiliary agent and the amount of water must be strictly controlled. The optimum conditions are (per gram of ore sample): NaOH 0.55 g, NaCl 0.60 g, water 3.00 g, and reaction time 4 hours. [next]

2, development and production examples At present, the zeolite mines in all parts of China are mainly for the sale of raw ore, used in the building materials industry, as a blend of cement production. Taking the Xintianji Zeolite Mine in Xinyang, Henan Province as an example, the annual mining volume is 300,000-400,000 tons, and almost all of the cement plants in Xinyang and Zhumadian areas are used as admixtures for cement production. The use of zeolite in industry and agriculture is still in the experimental stage. There are not many examples of development and application. Here are some examples of experimental research results: [next]
(1) NZp-series organic waste gas incineration purification catalyst (product).
Development unit: Catalysis Research Laboratory, Hangzhou University, Zhejiang Province Brief introduction: Research began in 80 years, developed into NZp-1 type in 81 years, and is being fully promoted. Developed into a NZp-2 type catalyst in 1982, it is being tested in the factory. The NZp-3 type catalyst was developed in 83 years and is being prepared for the pilot test.
NZp-1 is used for the treatment of triphenyl waste gas in paints, electrical equipment baking paint, etc., and NZp-2 is used in the treatment of phthalic anhydride waste gas from naphthalene. The NZp-3 type is used for the treatment of exhaust gas from the o-xylene process to produce phthalic anhydride.
Among the products, mordenite rock powder is used as a carrier of platinum . As of the end of 83, NZp-1 catalysts have been used in more than 20 factories, with a service life of 3 to 5 years and a maximum of 7 to 8 years.
Each plant in Hangzhou uses NZp-1 type catalyst (compared with the original honeycomb ceramic catalyst) to save the catalyst cost of 1,200 yuan.
The price of NZp-1 catalyst is only 1/3 of that of domestic pd-ceramic ceramics.
(2) Acid medium desiccant (product):
Development unit: Zigong Hongyi Chemical General Factory Brief introduction: The use of natural mordenite instead of 3A molecular sieve to dry hydrogen chloride, due to the low cost of natural zeolite, heat and acid resistance, can increase the service life of the product, greatly reducing production costs. [next]
(3) Potassium extraction test in seawater (expanded test)
Research units: Institute of Geology, Chinese Academy of Sciences, Tianjin Salt Industry Research Institute, Qinhuangdao Chemical Plant, Guangdong Huidong Potash Plant, Qingdao Chemical Research Institute, Zhejiang Meishan Salt Field and other units.
Brief introduction: The natural clinoptilolite ion exchange characteristics are used to replace sodium and potassium ions to achieve the purpose of extracting potassium salt from seawater.
The pilot plant of the Tianjin Salt Industry Research Institute with an annual output of 2,000 tons of KCl is simple, technically feasible and pollution-free. Due to the low potassium concentration in seawater, three-fold adsorption and one-time elution are generally used.
The process is not complicated, but the energy consumption is high, the cost is high, and the economy is not feasible, and further research is needed.
(4) Zeolite purification fish culture water production experiment (successful)
Development unit: Water Products Bureau of Chaoyang District, Liaoning Province Brief introduction: In order to improve the new process of biological water purification, the zeolite is used as a filter material for the filter press filter. The purpose is to observe the effect of the three-purpose (zeolite purification water body, recoil discharge, water circulation tower) which is actually applied to the production of the filter press filter tower.
It has purification, degradation and buffering effect on fish culture water. It is the ideal filter material for water purification. The purified water has good water quality and does not reach the pollution index that affects fish growth.
(5) Zeolite steel slag cement (ZSC)
Development unit: Beijing Steel Slag Cement Plant, Institute of Geology, Chinese Academy of Sciences, Beijing Building Materials Research Institute [next]
Brief introduction: Trial production in 1978, identification in November 1979, listed as a national product. It was officially put into production in March 1980. Its strength and performance have reached the national standard GB-1344-77 cement No. 325, that is, hard training No. 400, which is the first new cement product successfully developed at home and abroad. It belongs to one kind of non-clinker cement. The ingredients are: 60~70% of slow-cooled steel slag in pure oxygen top-blown converter; 25~30% of clinoptilolite; 8~10% of gypsum, respectively ground or mixed .
Steelmaking scrap can be used, the process is simple, the investment is small, the effect is quick, and it is also good for environmental protection. Special cement has high wear resistance, good corrosion resistance and low hydration heat.
According to some statistics: the use of Beijing Shougang converter slag can be used to produce 300,000 tons of cement per year.
Disadvantages: Grinding energy consumption is large.
(6) Application test for paper filler (commissioned)
Development unit: Institute of Geology, Chinese Academy of Sciences, Nenjiang Science and Technology Commission of Heilongjiang, Nenjiang Paper Printing Factory, Qiqihar Paper Mill, etc. Brief description: Nenjiang Paper Printing Factory uses local clinoptilolite as paper filler. From 1981.5 to 1983.10, the filling test of glossy paper, writing paper, wrapping paper, newsprint, etc. was completed. Except for the slight whiteness of glossy paper and writing paper, the other indicators reached the ministerial standard. It has been used in the production of yellow wrapping paper.
Qiqihar Paper Mill also planned to produce 10,000 tons of zeolite filler newsprint in 1984.
â‘  instead of talc as a filler, can reduce the cost to produce one thousand tons per annum writing paper, original plus 300 mesh talc Required fields 300 tons to zeolite powder, filler may be less branched costs 12,000 yuan. Qiqihar Paper Mill produces 50,000 tons of newsprint annually. It originally needed 200 tons of talc powder of 200 mesh. When it was changed to zeolite powder, it could cost less than 60,000 yuan. [next]
2 Under the same particle size, the same amount of addition, the same process conditions, the retention rate of zeolite powder is higher than that of talc. Taking writing paper as an example, the retention rate of zeolite powder is higher than 10%. According to the filling amount of 30%, 30kg of paper can be produced per ton of pulp. The price of writing paper is 1550 yuan/ton (82-year Heilongjiang unified price) The price of 30kg paper is about 46.5 yuan, which means that the value per ton of pulp can be 46.5 yuan. It is also calculated according to the annual output of 1000 tons of writing paper by Nenjiang Paper Mill. Under the same consumption, the annual profit is 46,500 yuan.
(7) As a livestock feed additive (product)
Development unit: Zhejiang Ninghai County Mining and Building Materials Company, Ninghai County Qingzhu Farm and Ninghai County Agriculture Bureau Animal Husbandry and Veterinary Units and other units Briefing: From July 1982 to August 1983, a total of 6 batches of 76 pigs were made. A comparison test of 2%, 5%, and 8% zeolite powder was added to the grain to obtain satisfactory results. It has been identified by the Provincial Agricultural University and the Provincial Feed Company that it is necessary to promote and apply it.
Ninghai County Mining Company Perlite Mine has boldly and innovatively designed compound zeolite powder, which has better weight gain effect than zeolite powder.
Adding zeolite powder to feed pigs makes the pig's fur bright and good appetite; it has certain effect on preventing and treating pig white diarrhea, diarrhea and rehabilitation of stiff pigs; when the feeding standard basically meets the nutritional needs, plus 5% fineness is 80 ~120 mesh, ammonium absorption greater than 164mmol / 100g zeolite powder, can obtain 5.44 ~ 15.7% weight gain effect.
Feed cost per 1 kg of live weight: The 5% zeolite powder group was reduced by an average of 0.06 yuan compared to the control.
(8) Ammonia-enhanced soil test Research unit: Ninghai County Science and Technology Commission, Mining Company, Agricultural Bureau System Brief: Zeolite has high cation exchange capacity and good adsorption performance, so it can improve soil and maintain fertility, and increase production. [next]
The county began the ammonia reform test in the spring of 1977. The test content includes a single application of zeolite powder, single-infiltration of seawater-containing zeolite powder, single-application ammonia water, zeolite powder mixed with ammonia water, no fertilization, and a plurality of comparative tests such as the amount of zeolite powder, the amount of ammonia water, and the depth of fertilization.
In the comparison of 29 groups, 16 groups with an increase of 5% or more increased the yield by more than 20%, and there were 3 groups with a reduction of 5% or less. The zeolite powder mixed with ammonia water was applied to the early rice to increase the yield by more than 5% than the light ammonia solution, and the yield increase was more obvious when the seawater was immersed in the seawater. After the application of the zeolite powder, the yield increase effect can still be seen in the later season crops. The yield increase effect of dryland crops corn and tomato is more obvious than that of rice. However, if the amount of ammonia is too much, it may cause poorness and suffer from pests and reduce production.
(9) Fertilizer and fertilizer absorption test Research unit: Department of Soil Chemistry, Jilin Agricultural University Brief introduction: From November 26, 1982 to January 4, 1983, the following experiments were carried out with Jiutai zeolite powder from Jilin Province:
1 Fertilization test: 1000 g of salted meadow soil, 60 g of zeolite, 20 g of ammonium bicarbonate and 20 g of stone were placed in a culture pot for testing.
2 Fertilizer absorption test: 10 g of zeolite was mixed with 1 g of fertilizer, and 50 ml of distilled water was added for the test.
3 volatile ammonia reduced the loss by 21.86% compared with the control, and the loss of leaching ammonium decreased by 65.02%. Leaching phosphorus treatment also reduced the loss by 43.7% compared with the control. 2 Zeolite had different degrees of absorption of nitrogen, phosphate and potassium fertilizers. The absorption of ammonia and ammonium bicarbonate was the best in nitrogen fertilizer.
(10) Feed additive research unit: Heilongjiang Feed Company Profile: For weaned pigs weighing 20~25 kg, the weight of 5% clinoptilolite in the feed is increased by 21% every day, plus 100g, 50g can increase It weighs 10.6%.
In the mechanized cage chicken farm, adding 5% zeolite powder to the feed can reduce the humidity and deodorization in the house. 20~30% of zeolite powder is scattered on chicken manure, which can receive the effect of dehydration and drying.
Improve the weight of livestock and reduce the humidity and deodorization of the farm.

TUBING

Tubing is mainly used to provide oil and gas flow passage during production of oil and gas wells. For flowing wells, due to the large inner diameter of the CASING, the casing is directly used for production. Due to the density difference, pressure drop and expansion, the liquid flows up rapidly, causing the liquid to slip, resulting in the ineffective utilization of the downhole elastic energy. Running tubing with smaller OD and ID during production can effectively solve the above problems by allowing fluid to flow in the tubing. Therefore, running tubing is required during production of flowing wells. The downhole operation and production of flowing well and non flowing well can be completed by using various tools for tubing running.