A processing method for deep-sea sediments

Abstract

The present invention discloses a processing method for deep-sea sediments, which relates to the technical field of deep-sea sediment treatment. Through a series of treatments on deep-sea sediments, they can be processed into planting soil and environmentally friendly permeable bricks. Deep-sea soil contains a certain amount of microorganisms including bacteria, fungi, viruses, protozoa, etc. After a series of treatment methods such as pH adjustment, dehydration, solidification, and improvement, the heavy metal content in the deep-sea soil may change and can be used as crop planting soil, which can promote plant growth; the environmentally friendly permeable bricks can, through their special pore structure, quickly infiltrate rainwater into the groundwater layer, reduce waterlogging in the city, and at the same time can also reduce the impact of rainwater runoff on the urban drainage system and reduce the risk of urban waterlogging. The method of the present invention improves the comprehensive utilization efficiency of marine resources.

Description

Technical Field

[0001] The present invention relates to the technical field of deep - sea sediment treatment, and particularly relates to a processing method for deep - sea sediments. Background Art

[0002] Deep - sea sediments are mainly composed of marine biological remains, authigenic sediments, aeolian dust, cosmic dust, volcanic ash, terrigenous clay colloids, and ice - raft debris; they are mainly the products of biological and chemical actions, and also include terrigenous, volcanic, and cosmic substances. Among them, turbidity currents, ice - borne, aeolian, and volcanic materials can also be the main sources in some ocean bottoms. During deep - sea mining operations, mineral cutting, collection, washing, crushing, grinding, etc. during seabed mining, as well as the movement of ore collectors, will inevitably generate sediment plumes; sediment plumes will cause damage to the deep - sea ecosystem, and burial will cause benthic organisms to suffocate, and the intake of non - nutritious or low - nutritious particulate matter will also lead to starvation or slowed growth of near - bottom organisms, etc. In the current deep - sea mining process, the generation of a part of the plume is mainly pre - treated by a water - lift system or a chain - bucket system to convey the surface - supported mother ship. The tailings generated by the pre - treatment, including wastewater, sediments, and fine solid particulate matter generated by ore crushing and abrasion, will be discharged back into the ocean, generating sediment plumes at the discharge point.

[0003] Sediments have the disadvantages of containing more salts, having a higher water content, and poor permeability, etc.; high salt content is the main environmental factor restricting crop growth, and poor permeability is not conducive to the respiration of crops, and at the same time will also affect the activities of soil microorganisms, leading to the gradual accumulation of harmful substances, and then affecting the quality and growth and development of crops; therefore, it is very difficult to directly use them without processing and treatment. Summary of the Invention

[0004] The purpose of the present invention is to provide a processing method for deep - sea sediments, which can process sediments into planting soil and environmentally friendly permeable bricks, improving the comprehensive utilization efficiency of marine resources.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A processing method for deep - sea sediments successively includes the following steps:

[0007] a. Separating solid fine particulate matter from the collected deep - sea sediments through a slime separation device to obtain Sediment I;

[0008] b. Adding a flocculant to Sediment I, allowing it to precipitate for a period of time, and filtering out the upper - layer seawater to obtain Sediment II;

[0009] c. Stir the sediment II to homogenize it; then add organic polyacrylamide, polyaluminum chloride, and a modifier thereto, and continue stirring;

[0010] d. Feed the mixture obtained in step c into a sludge separation device for dehydration treatment. The desalinated seawater obtained by dehydration separation is desalinated by vacuum distillation and used as drinking water or agricultural irrigation water; the sediment III obtained by dehydration separation has a moisture content of 30 - 70%;

[0011] e. Part of the sediment III enters the planting soil system and is processed into planting soil required for crops in the planting soil system;

[0012] f. Another part of the sediment III enters the permeable brick system. In the permeable brick system, it first enters the drying chamber of the permeable brick system for drying to obtain sediment V, and the heavy metal content therein is adjusted by adding a microbial agent to sediment V to meet the standards;

[0013] g. Dry the sediment V with qualified heavy metal content obtained in step f to remove excess moisture;

[0014] h. Crush the floating garbage in the ocean and put it into a ball mill for ball milling to make it into fine granular;

[0015] i. Add the granular floating garbage in step h to the dried sediment V obtained in step g, and the formed mixture is pressed into bricks in a high-temperature refractory mold under a pressure of 5 - 25 MPa; then the obtained bricks are dried, and the dried brick samples are fired in an electric furnace at a temperature of 1100 - 1200 °C at a heating rate of 4 °C / min for a period of time, and after firing, the bricks are cooled to room temperature by natural convection in the electric furnace to make environmentally friendly permeable bricks.

[0016] In the above processing method of a deep-sea sediment, in step e, in the planting soil system, the sediment III is mixed with a soil conditioner, cation exchange resin, anion exchange resin, and a pH modifier to obtain sediment IV, and a microbial agent is added to sediment IV, and the heavy metal content in sediment IV is reduced by the microbial agent.

[0017] In the above processing method of a deep-sea sediment, the soil conditioner includes 1% - 5% of silicate cement curing agent, 2% - 10% of biochar, and 1% - 10% of incinerator ash; the pH modifier is humic acid; the addition amounts of the cation exchange resin and the anion exchange resin are 1% - 10% of the mass of the sediment III.

[0018] In the above processing method of deep - sea sediment, after sediment III is mixed with cation - exchange resin and anion - exchange resin, it is placed in mixer II, with a stirring speed of 100 - 200 r / min and a stirring time of 20 - 40 min. Then it enters a centrifugal filter, and in the centrifugal filter, the resin and sediment are separated by centrifugal sedimentation. After separation, the sediment is at the bottom, and the cation - exchange resin and anion - exchange resin are in the upper liquid.

[0019] In the above processing method of deep - sea sediment, in step a, solid fine particles are screened out through vibration and a sieve in the ore sludge separation device, and the sieve is 250 mesh.

[0020] In the above processing method of deep - sea sediment, in step c, the modifier is prepared by mixing industrial waste steel slag and phosphogypsum as the main raw materials with water; the addition amount of the modifier is 0.25% of the weight of the deep - sea sediment; the addition amount of the organic polyacrylamide is 0.1% - 0.3% of the dry weight of the sediment; the stirring speed is 150 - 200 r / min, and the stirring time is 5 - 15 min.

[0021] In the above processing method of deep - sea sediment, in step f, the mass of the microbial inoculum is 1% - 2% of the mass of sediment V; in step g, drying is carried out in a drying chamber, with a drying temperature of 100 - 110 °C and a drying time of 20 - 30 h.

[0022] In the above processing method of deep - sea sediment, in step i, the floating garbage includes plastic products and glass products. Among them, the mass of the plastic products is 10% - 30% of the mass of sediment V, and the mass of the glass products is one - third of the mass of sediment V.

[0023] The microbial inoculum is co - cultured with the sulfate - reducing bacteria culture SRB, / mass of deep - sea sediment = 0.02 g / g, volume ratio of sulfate - reducing bacteria / deep - sea sediment = 10 mL / 100 mL.

[0024] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0025] The present invention provides a processing method for deep - sea sediments. By processing deep - sea sediments, they can be processed into planting soil and environmentally - friendly permeable bricks. When deep - sea sediments are processed into planting soil, compared with soilless cultivation for growing crops such as vegetables and fruits, on the one hand, soilless cultivation has relatively large investment, high technical requirements, and improper management is likely to cause large - scale spread of certain diseases. Moreover, the substrate needs to be replaced after about one year or one and a half to two years. On the other hand, in the context of the increasingly depleted earth resources, using deep - sea soil for agricultural production can improve the comprehensive utilization efficiency of marine resources, reduce the formation of deep - sea plumes, and reduce marine pollution. Deep - sea soil contains a variety of natural organic matters and mineral elements, which can provide comprehensive and balanced nutrient components for crops, has good fertility, can reduce soil loss and erosion, is conducive to maintaining the balance of the soil ecosystem, and contains trace elements such as rare elements required by the human body. And deep - sea soil contains a certain amount of microorganisms including bacteria, fungi, viruses, protozoa, etc., which can decompose organic substances, promote the circulation of soil organic matter, can also provide nutrients for other organisms, can assist plants in the cycling of nitrogen and phosphorus, promote plant growth and development, and can also participate in biogeochemical cycles, such as the transformation processes of elements such as carbon, nitrogen, and sulfur, and also has the potential for pollution control. Deep - sea soil is usually fine - grained, with uniform and rounded particles and stable physical properties. Compared with processing near - shore clay and marine silt into planting soil, deep - sea soil requires solidification and permeability - increasing treatment. Near - shore clay and marine silt are mostly coarse - grained or mixed with various debris, have a certain fluidity, and the content of microorganisms and organic matter in deep - sea soil is higher than that in near - shore clay and marine silt, which is beneficial to plant growth.

[0026] When deep - sea sediments are processed into environmentally - friendly permeable bricks, the environmentally - friendly permeable bricks have a special pore structure, which can quickly infiltrate rainwater into the groundwater layer, reduce waterlogging in the city, and at the same time can also reduce the impact of rainwater runoff on the urban drainage system and reduce the risk of urban waterlogging. In addition, it can effectively reduce pollutant emissions in the city. Through the filter layer on its surface, impurities and pollutants in rainwater can be filtered out, reducing environmental pollution. Therefore, environmentally - friendly permeable bricks play an important role in urban construction and can improve the environmental protection level and ecological environment quality of the city.

[0027] In the processing method of deep - sea sediments, the deep - sea sediments are successively passed through steps such as a vibrating screen, adding a flocculant, sediment homogenization, and dehydration to obtain sediments with a moisture content of 30% - 70%. Then they are respectively fed into the planting soil system and the permeable brick system for further processing into planting soil and environmentally - friendly permeable bricks. The process of the present invention is simple in operation and can be widely used. Brief Description of the Drawings

[0028] The following further describes the present invention with reference to the accompanying drawings:

[0029] Figure 1 This is the processing flowchart of the deep-sea sediment of the present invention;

[0030] Figure 2 This is the structural schematic diagram of the device required for the deep-sea sediment of the present invention;

[0031] Figure 3 This is the collection schematic diagram of the deep-sea sediment of the present invention;

[0032] Figure 4 This is the structural schematic diagram of the pretreatment of the deep-sea sediment of the present invention;

[0033] Figure 5 This is the structural schematic diagram of the planting soil system of the present invention;

[0034] Figure 6 This is the structural schematic diagram of the permeable brick system of the present invention;

[0035] In the figure:

[0036] 1. Pipeline, 2. Slurry separation device, 3. Storage tank, 4. Mixer 1, 5. PAM storage tank, 51. Discharger 1, 61. Discharger 2, 6. Modifier storage tank, 7. Mud-water separation device, 71. Control valve, 8. Planting soil system, 81. Mixer 2, 82. Cation exchange resin storage tank, 83. Anion exchange resin storage tank, 821. Discharger 3, 831. Discharger 4, 84. Centrifugal filter, 85. Mixer 3, 86. Modified pH agent storage tank, 87. Soil conditioner, 88. Microbial inoculant storage tank 1, 861. Discharger 5, 871. Discharger 6, 881. Discharger 7, 9. Permeable brick system, 91. Mixer 4, 92. Microbial inoculant storage tank 2, 921. Discharger 8, 93. Drying chamber, 94. Mixing chamber, 95. Plastic product storage tank, 96. Glass product storage tank, 951. Discharger 9, 961. Discharger 10, 97. Crusher, 98. Ball mill, 99. High-temperature refractory mold, 910. Oven, 911. Electric furnace. Detailed implementation manners

[0037] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application.

[0038] In the description of the present application, words such as "mixer 1" and "mixer 2" are only used to distinguish different objects, and do not limit the quantity and execution order, and words such as "mixer 1" and "mixer 2" do not necessarily mean different. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion.

[0039] The technical solution of the present application will be further described in detail below with reference to the accompanying drawings.

[0040] As Figure 3 shown, the schematic diagram of collecting deep-sea sediments of the present invention. The sediments collected by the deep-sea sediment collection vehicle are transported to the ship. A mixture treatment and processing system is installed on the ship. By means of the mixture treatment and processing system and in combination with the processing method of the present invention, the deep-sea sediments can be processed into planting soil and environmentally friendly permeable bricks.

[0041] Combined with Figure 1 、 Figure 2 、 Figure 4 shown, the specific processing system includes a pipeline 1, a slime separation device 2, a storage tank 3, a first mixer 4, a PAM tank 5, a first discharger 51, a second discharger 61, a modifier storage tank 6, a mud-water separation device 7 and a control valve 71. Among them, the pipeline 1 transports the deep-sea sediments into the slime separation device 2. The slime separation device 2 uses a sieve with a pore size of 250 mesh; through vibration and screening, solid fine particles generated by ore crushing and wear are separated to obtain sediment I;

[0042] The outlet of the slime separation device 2 is connected to the inlet of the storage tank 3. Sediment I flows into the storage tank, and a flocculant is added thereto and stirred evenly to precipitate impurities and particulate matters suspended in the water; after precipitation for 12 hours, the upper-layer seawater is filtered out to obtain sediment II;

[0043] Sediment II is pumped into the first mixer 4 by a suction pump. After sediment II is stirred in the first mixer for about 10 minutes, sediment II is homogenized to facilitate the full dissolution of the added chemical substances into sediment II. The PAM tank 5 and the modifier storage tank 6 are connected to the first mixer 4, and corresponding first dischargers 51 and second dischargers 61 are provided on the pipelines connecting the PAM tank 5 and the first mixer 4, and the modifier storage tank 6 and the first mixer 4. The modifier storage tank 6 contains a low-alkali sludge modifier. The modifier storage tank 6 controls the feeding of the modifier into the first mixer 4 through the second discharger 61 and is fully stirred in the first mixer 4. The sediment II after stirring (quenching treatment) is transported to the mud-water separation device 7 for dehydration treatment. Part of the obtained sediment III after treatment enters the planting soil processing system 8 through the control valve 71, and the other part enters the permeable brick system 9.

[0044] The above-mentioned mud-water separation device 7 can be realized by referring to the prior art. It mainly uses an inclined plate sedimentation tank to separate sediment II from wastewater. The mixture enters the thin plate separator through the inlet. The sewage flows downward in the middle channel. Part of the sediment settles in the sludge hopper under the action of gravity, and part of it moves upward along the inclined plate with the water. The sediment particles precipitate on the inner side of the layer plate and then enter the sludge hopper. The outflow of the sediment is controlled through the sludge hopper.

[0045] Before the dehydration treatment, the sediment is conditioned, that is, organic polyacrylamide and a modifier are added to mixer 1. The purpose is to add a conditioner that can play an electrical neutralization or adsorption bridging role in sediment II by adding organic polyacrylamide and the modifier, so as to destroy the stability of the colloidal particles in sediment II, make the dispersed small particles aggregate with each other to form large particles, thereby improving the dehydration performance of the sediment. After the conditioned sediment is dehydrated in a mud-water separation device, the separated seawater is desalinated by vacuum distillation and can be used for drinking water, agricultural irrigation, etc.

[0046] Combined with Figure 5 As shown, the planting soil system includes mixer 2 81, cation exchange resin tank 82, anion exchange resin tank 83, discharger 3 821, discharger 4 831, centrifugal filter 84, mixer 3 85, modified pH agent tank 86, soil conditioner 87, microbial inoculant tank 1 88, discharger 5 861, discharger 6 871, discharger 7 881. Among them, the cation exchange resin tank 82 and the anion exchange resin tank 83 are respectively connected to mixer 2 81. And a discharger 3 821 is also provided between the cation exchange resin tank 82 and mixer 2 81, and a discharger 4 831 is provided between the anion exchange resin tank 83 and mixer 2 81. In mixer 2, the stirring speed is 100 - 200 r / min, and the stirring time is about 30 min, and it is transported to the centrifugal filter 84 for separation of resin and sediment; the separated resin can be treated with an alkali solution to remove adsorbed Na + ions, etc., to make the resin available again. The separated sediment enters mixer 3 85, the modified pH agent tank 86 and the soil conditioner 87, and are respectively mixed with the separated sediment in mixer 3 85 through discharger 5 861 and discharger 6 871 at a speed of 200 - 250 r / min, with a stirring time of 15 - 20 min, and wait for 24 h. Then, a part of the fully stirred deep-sea soil is taken out as a sample to measure whether the heavy metal content and salt content meet the standards of "Soil Environmental Quality Risk Control Standards for Agricultural Land Soil Pollution (Trial)". If it meets the standards, suitable crops can be planted; if not, the microbial inoculant tank 1 88 enters mixer 3 85 through discharger 7 881, and is also stirred at a speed of 200 - 250 r / min, with a stirring time of 15 - 20 min, and wait for 24 h.

[0047] The cation exchange resin tank 82 contains cations, and the anion exchange resin tank 83 contains anions. Its working principle is that in the aqueous solution in the environment where the ion exchange resin acts, the metal cations (Na + 、Ca 2+ 、K+ , Mg 2+ , Fe 3+ , etc.) and cation exchange resins (containing acidic groups such as sulfonic acid groups (—SO3H), carboxyl groups (—COOH), or phenol groups (—C6H4OH), which are prone to generate H + ions) on the H + for ion exchange, so that the cations in the solution are transferred to the resin, and the H + on the resin is exchanged into the water, (which is the principle of cation exchange resin); the anions (Cl - , HCO3 - , etc.) in the aqueous solution and anion exchange resins (containing basic groups such as quaternary amine groups [-N(CH3)3OH], amine groups (—NH2), or imine groups (—NH2), which are prone to generate OH - ions) on the OH - for exchange, the anions in the water are transferred to the resin, and the OH - on the resin is exchanged into the water, (which is the principle of anion exchange resin); and H + combines with OH - to form water, thereby achieving the purpose of desalination. The addition amounts of cation exchange resin and anion exchange resin are 1% - 10% of the mass of Sediment III.

[0048] The soil conditioner includes 1% - 5% of silicate cement curing agent, 2% - 10% of biochar, and 1% - 10% of incinerator ash; the pH modifying agent is humic acid; the addition amounts of cation exchange resin and anion exchange resin are 1% - 10% of the mass of Sediment III.

[0049] The above-mentioned biochar is mainly a product with extremely high carbon content formed by various materials such as animal manure and marine floating garbage like wood under the condition of high temperature and anaerobic; it is a solid substance with a large specific surface area, loose pores, and extremely high carbon content; it can enhance the cation exchangeability in the soil. The porosity of biochar can also improve the soil structure, increase the aeration and water permeability of the soil, and improve the water and fertilizer utilization efficiency of the soil; and the combination of biochar and organic fertilizer can promote the formation of soil aggregate particles, promote the replacement of calcium ions and magnesium ions, reduce the sodium ion content, and increase the calcium ions and magnesium ions beneficial to plants.

[0050] The above-mentioned Portland cement solidifying agent kills harmful microorganisms, germs, insect eggs and other organisms through cement hydration reaction, and has a good stabilization effect on pollutants such as heavy metals. The solidifying agent first reacts with water to generate gel-like hydrates such as calcium silicate hydrate, calcium aluminate hydrate, and calcium sulfate hydrate. These hydrates react with the active components of minerals in the soil to form flaky, fibrous or needle-like crystals, which intersect with each other to enhance the connection between soil particles and form a stable network structure in the soil, making the structure of the solidified soil more stable. Some also generate expansive substances that can fill the pores between the network structures or improve the pore structure in the soil, thereby increasing the soil strength.

[0051] The above-mentioned incinerator ash residue refers to the solid residue generated by burning garbage and waste in the incinerator of a ship. Incinerator ash residue is usually the ash remaining during the combustion process and the fragments of unburned waste, which can loosen the soil without hardening, increase soil pores, reduce soil bulk density, and can play a role in absorbing water and preventing waterlogging, and loosening and improving the soil.

[0052] The above-mentioned humic acid is a type of macromolecular substance widely present in the natural environment and is formed by the complex biological and chemical actions of plant and animal residues. The mass concentration of the humic acid aqueous solution is 1.5% - 2.5%. It can adjust the pH value of the sediment; improve the soil aggregate structure to prevent soil deterioration, increase soil porosity and water holding capacity, improve the cold resistance of crops, darken the soil color, which is beneficial to increasing the ground temperature; improve and optimize the absorption of nutrients and water by plants; be rich in organic matter and minerals necessary for plant growth, improve the solubility of inorganic fertilizers, reduce fertilizer loss, and convert nutrient elements into a state easily absorbed by plants; can strengthen the absorption of nitrogen by plants, reduce the fixation of phosphorus, store elements such as nitrogen, phosphorus, and potassium deep in the soil, and enable nutrient elements to quickly enter the plant body, improving the utilization rate of inorganic fertilizers; can also promote the activities of microorganisms in the soil, increase the number of soil microorganisms, and enhance the activity of enzymes in the soil, which can promote the growth and development of plants and their internal physiological metabolism.

[0053] The above-mentioned microbial inoculant: Co-cultured with a sulfate-reducing bacteria culture (SRB), The added amount is / The mass of deep - sea sediment is 0.02 g / g and the amount of sulfate - reducing bacteria added is sulfate - reducing bacteria / deep - sea sediment = 10 mL / 100 mL. Zero - valent iron can stimulate the activity of sulfate - reducing bacteria. Iron - containing compounds from zero - valent iron and the products of sulfate - reducing bacteria (such as sulfide, sulfite, and thiosulfate) will combine with heavy metals to form more stable components. Among them, sulfate - reducing bacteria can also decompose organic substances, such as plant residues and animal feces, and convert them into nutrients that can be absorbed and utilized by plants, such as nitrogen, phosphorus, and potassium. At the same time, the products of organic matter decomposition can increase the fertility of the soil. Some microorganisms, such as ammonia - oxidizing bacteria and nitrifying bacteria, can convert ammonia nitrogen into nitrate nitrogen to achieve nitrification of nitrogen, making it easier to absorb and utilize. Microorganisms will also secrete adhesive substances and form bio - colloids, which can bond fine - grained soil together to form stable soil aggregates. These aggregates help improve the soil structure, retain moisture, increase air permeability, and resistance to erosion.

[0054] Organic polyacrylamide (PAM): It is a white powder, anionic type. To a certain extent, it can also reduce the cation concentration in deep - sea soil and increase the permeability of deep - sea soil. The mass percentage of the solution used is 0.25%, and the input amount is 0.1% - 0.3% of the dry weight of the sediment.

[0055] Modifier: It is obtained by mixing low - alkaline industrial waste steel slag and phosphogypsum as the main raw materials with water. Its appearance is gray powder and it has low alkalinity. The addition amount of the modifier is 0.25% of the sediment weight.

[0056] Due to the softness and low strength of deep - sea soil, deep - sea sediments have the characteristics of large porosity, high plasticity, a sensitivity coefficient between 4.5 and 6.7, belonging to highly sensitive soil, significant increase in soil weight after encountering water, and poor permeability, lacking the stability for use as normal soil. Therefore, after dehydration, soil improvement and solidification agents can be added to the deep - sea soil for soil improvement and solidification.

[0057] The process of desalination and improvement and solidification of deep-sea sediments may cause the pH of deep-sea sediments to increase. The pH of sediment soil needs to be controlled at 6.5-7.5 to facilitate plant growth. The pH value of the soil can be changed by adding alginate to promote plant growth. After the deep-sea soil has been treated by a series of methods such as adjusting pH, dehydration, solidification and improvement, the heavy metal content in the deep-sea soil may change. Therefore, the heavy metal content in the deep-sea soil can be determined by an inductively coupled plasma mass spectrometer method, and judged according to the "Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard (Trial)", if the heavy metal content of the deep-sea soil does not exceed the standard of the "Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard (Trial)", suitable crops can be planted; if the heavy metal content of the deep-sea soil exceeds the standard of the "Soil Environmental Quality Agricultural Land Soil Pollution Risk Control Standard (Trial)", since microbial technology has the advantages of low investment and less environmental interference, it is an ideal technology for reducing the heavy metal content. In order to more efficiently reduce the heavy metal content, the present invention uses chemical agents and microbial agents to synergistically reduce the heavy metal content in the deep-sea soil, stir in a mixer at a speed of 200~250 r / min, stir for 15~20min, wait for 24h, and complete the processing of the planting soil after sufficient stirring. Finally, the excrement of crew members and tourists can be added to the mixed compost with kitchen waste, and applied to crops after a certain period of time. Before actually using the sediment to make planting soil, some soil tests are needed, such as tests on soil structure, fertility, and nutrient content, to determine the suitability of the soil and plant suitable crops to achieve the best results.

[0058] like Figure 6As shown, another part of the sediment III enters the permeable brick system, which includes a mixer four 91, a microbial inoculant tank two 92, a discharger eight 921, a drying chamber 93, a mixing chamber 94, a plastic product tank 95, a glass product tank 96, a discharger nine 951, a discharger ten 961, a crusher 97, a ball mill 98, a high-temperature refractory mold 99, an oven 910, and an electric furnace 911. The mixer four is connected to the microbial inoculant tank two 92. First, measure the heavy metal content in the sediment III. According to the standard of "Limit of Hazardous Substances in Wall Coatings for Building Use" (GB18582-2020), if the heavy metal content needs to be reduced, add a heavy metal reducing agent. If not satisfied, reduce the heavy metal content in the sediment by adding a microbial inoculant accounting for 1% - 2% of the mass of the deep-sea sediment. Dry the sediment with reduced heavy metal content in the drying chamber at 105°C for 24 hours to remove excess moisture. Specifically, the microbial inoculant tank two 92 enters the mixer four 91 through the discharger eight 921 and is stirred at a speed of 200 - 250 r / min for 15 - 20 min and waits for 24 h. Then, transport the sediment to the drying chamber 93 through a suction pump, dry it at about 105°C for 24 h to remove excess moisture, and then transport the sediment to the mixing chamber 94.

[0059] The plastic product tank 95 and the glass product tank 96 enter the crusher 97 for crushing through the discharger nine 951 and the discharger ten 961 respectively, and are ball-milled in the ball mill 98 for 2 hours. The grinding is to break the agglomeration of the powder and screen it into an aggregate size less than 1 mm and a particle size of 0.131 - 0.154 mm. Then, the waste plastic accounts for 10% - 30% of the mass of the sediment V, and the mass ratio of the sediment V to the glass powder is 3:1. They are fully mixed in the mixing chamber 94. After mixing, they are pressed into bricks in the high-temperature refractory mold 99 at 5 - 25 MPa. Then, the obtained bricks are transported to the oven 910 and dried for 12 h. Subsequently, they are fired in the electric furnace 911 at a heating rate of 4°C / min within the temperature range of 1100 - 1200°C. After firing for about 30 minutes at the required temperature, the bricks are cooled to room temperature by natural convection in the electric furnace to make environmentally friendly permeable bricks.

[0060] In summary, the processing method of deep-sea sediments provided by the present invention processes them into planting soil and permeable bricks. The planting soil is usually fine-grained, with uniform and round particles and stable physical properties. Compared with processing nearshore clay and marine silt into planting soil, deep-sea soil requires solidification and permeability enhancement treatment. Nearshore clay and marine silt are mostly coarse-grained or mixed with various debris and have a certain fluidity. Moreover, the content of microorganisms and organic matter in deep-sea soil is higher than that in nearshore clay and marine silt, which is beneficial to plant growth. The permeable bricks can quickly infiltrate rainwater into the groundwater layer through their special pore structure, reducing waterlogging in the city. At the same time, it can also reduce the impact of rainwater runoff on the urban drainage system and lower the risk of urban waterlogging. In addition, it can effectively reduce pollutant emissions in the city. Through the filter layer on its surface, impurities and pollutants in rainwater can be filtered out, reducing environmental pollution. Therefore, the environmentally friendly permeable bricks play an important role in urban construction and can improve the environmental protection level and ecological environment quality of the city.

[0061] The parts not described in the present invention can be realized by referring to the prior art.

[0062] It should be noted that those of ordinary skill in the art should recognize that the above embodiments are only used to illustrate the present application and are not intended to limit the present application. As long as appropriate changes and variations made to the above embodiments fall within the scope of the spirit of the present application, they fall within the scope claimed by the present application.

Claims

1. A processing method for deep-sea sediments, characterized in that, The following steps are included in sequence: a. Separating the collected deep-sea sediments into solid fine particles through a sludge separation device to obtain sediment I; b. Add flocculant to sediment I, let it settle for a period of time, filter out the upper seawater, and obtain sediment II; c. Stir the sediment II to homogenize the sediment II; then add organic polyacrylamide, polyaluminium chloride and a modifier thereto and continue stirring; d. Sending the mixture obtained in step c to a mud-water separation device for dehydration treatment, and the seawater obtained by dehydration separation can be desalinated by vacuum distillation to be used as drinking water or agricultural irrigation water; the sediment III obtained by dehydration separation has a water content of 30-70%; e. A portion of sediment III enters the planting soil system, where it is processed into planting soil required for crops; f. Another part of sediment III enters the permeable brick system, where it first enters the drying room of the permeable brick system for drying to obtain sediment V, and then microbial agents are added to the sediment V to adjust the heavy metal content therein and make it meet the standards; g. Drying the sediment V with the heavy metal content meeting the standard in step f to remove excess water; h. Crush the floating garbage in the ocean and put it into a ball mill to make it into fine particles; i. Add the granular floating garbage in step h to the sediment V dried in step g, and press the resulting mixture into bricks in a high-temperature refractory mold at a pressure of 5 to 25 MPa; then dry the obtained bricks, and burn the dried brick samples in an electric furnace at a temperature of 1100 to 1200° C. and a heating rate of 4° C. / min for a period of time, and after burning, cool the bricks to room temperature by natural convection in the electric furnace to make environmentally friendly permeable bricks; In step c, the modifier is prepared by mixing industrial waste steel slag and phosphogypsum as main raw materials with water; the amount of the modifier added is 0.25% of the weight of the deep-sea sediment; the amount of the organic polyacrylamide added is 0.1% to 0.3% of the dry weight of the sediment; the stirring speed is 150 to 200 r / min, and the stirring time is 5 to 15 minutes; In step e, in the planting soil system, the sediment III is mixed with a soil conditioner, a cation exchange resin, an anion exchange resin and a pH-improving agent to obtain a sediment IV, a microbial agent is added to the sediment IV, and the heavy metal content in the sediment IV is reduced by the microbial agent; The soil conditioner includes 1% to 5% of silicate cement curing agent, 2% to 10% of biochar and 1% to 10% of incinerator ash; the pH improving agent is humic acid; the addition amount of the cation exchange resin and the anion exchange resin is 1% to 10% of the mass of the sediment III; After the sediment III is mixed with cation exchange resin and anion exchange resin, it is placed in the second blender, with a stirring speed of 100-200 r / min and a stirring time of 20-40 min. Then it enters the centrifugal filter, and in the centrifugal filter, the resin and sediment are separated by centrifugal precipitation. After separation, the sediment is at the bottom, and the cation exchange resin and anion exchange resin are in the upper liquid.

2. The processing method of a deep-sea sediment according to claim 1, wherein, In step a, solid fine particles are screened out through vibration and a sieve in the slime separation device, and the sieve is 250 mesh.

3. A processing method for deep-sea sediments according to claim 1, characterized in that, In step f, the mass of the microbial inoculant is 1%-2% of the mass of sediment V; in step g, drying is carried out in a drying chamber at a drying temperature of 100-110 °C and a drying time of 20-30 h.

4. A method for processing deep-sea sediments according to claim 1, characterized in that, In step i, the floating garbage includes plastic products and glass products. Among them, the mass of the plastic products is 10%-30% of the mass of sediment V, and the mass of the glass products is one-third of the mass of sediment V.

5. The processing method of a deep-sea sediment according to claim 1, characterized in that The described microbial inoculum is co-cultured with a sulfate-reducing bacterium culture SRB, / mass of deep-sea sediment = 0.02 g / g, volume ratio of sulfate-reducing bacterium to deep-sea sediment = 10 mL / 100 mL.

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