Slow release complex for water treatment and method for its preparation

Abstract

The application discloses a slow-release composite for water treatment, which is prepared by mixing and pressing raw materials including aggregate, sodium silicate, pore-forming agent, slow-release carrier, low-melting-point organic matter and adhesive agent, wherein the aggregate is 10-40 parts, the sodium silicate is 2-5 parts, the pore-forming agent is 10-60 parts, the slow-release carrier is 10-40 parts, the low-melting-point organic matter is 1-3 parts, the adhesive agent is 5-15 parts, and the water is 1-3 parts in terms of mass fraction. The slow-release composite prepared by the application has high strength and can slowly decompose in water, and the release speed is controllable; the slow-release composite releases the functional components loaded in the interior to stabilize the concentration of microorganisms and trace elements in water and improve the quality of the water environment. The loading amount of the functional components in the slow-release composite prepared by the application can reach 5-30%, and the slow-release period can be 10-100 days; different functional components and contents and different slow-release periods can be selected according to the requirements of different water environments to achieve the purpose of adjusting the water environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of water purification, in particular to a slow-release complex for water treatment and a preparation method thereof. BACKGROUND

[0002] With the rapid development of China's economy and the acceleration of urbanization, water environmental pollution and ecological destruction are increasingly prominent, and water bodies are particularly critical in the protection and management of ecological environment. Maintaining sufficient concentration of functional microorganisms is a basic prerequisite for efficient water purification, but due to the deterioration of environmental conditions or the characteristics of wastewater quality, functional microorganisms cannot exist stably for a long time, which brings great challenges to the stability of water quality. For water ecological restoration, modern technology has formed a variety of technologies, such as ecological biological technology, which introduces excellent and efficient metabolic ability of synergistic bacteria, controls the growth of harmful microorganisms in water, and inhibits the content of toxic and harmful substances such as heavy metals and organic matter in water, so as to improve the stability and resistance of the ecological system.

[0003] However, the addition of functional microorganisms can only ensure a high concentration in the short term, and cannot achieve long-term sustained effect. It is difficult to maintain the concentration of functional microorganisms in a certain range for a long time, therefore, it is necessary to seek a slow-release of functional substances in water to maintain a certain concentration for a long time and stabilize the microecosystem in water. At present, mature products about slow-release technology are mainly in the United States and Australia, and domestic slow-release technology is mostly in the laboratory research stage, lacking mature products. The main technical bottleneck is that the slow-release rate is difficult to control, and the release speed cannot be controlled as needed; the preparation method is complex, the production cost is high, and it is difficult to realize large-scale production. SUMMARY

[0004] Based on the above technical problems, the present application aims to provide a slow-release complex for water treatment.

[0005] Another object of the present application is to provide a preparation method of the slow-release complex. The prepared slow-release complex has excellent controllable slow-release effect, can release slowly by loading different functional ingredients in water environment, and achieves the purpose of improving water environment.

[0006] The object of the present application is achieved by the following technical scheme:

[0007] A slow-release complex for water treatment, characterized in that: the raw materials of the slow-release complex include aggregate, sodium sesquicarbonate, pore-forming agent, slow-release carrier, low-melting-point organic matter, adhesive and water, which are mixed and pressed to form.

[0008] Further, the aggregate is 10-40 parts, the sodium silicate is 2-5 parts, the pore-forming agent is 10-60 parts, the slow-release carrier is 10-40 parts, the low-melting organic matter is 1-3 parts, the adhesive is 5-15 parts, and the water is 1-3 parts, all by mass fraction.

[0009] Preferably, the aggregate is 25-40 parts, the sodium silicate is 3-4 parts, the pore-forming agent is 15-25 parts, the slow-release carrier is 25-35 parts, the low-melting organic matter is 1-3 parts, the adhesive is 5-8 parts, and the water is 2 parts, all by mass fraction.

[0010] Further, the low-melting organic matter has a melting point of 40-70°C.

[0011] Further, the low-melting organic matter includes, but is not limited to, a composition of urea and benzoic acid in a mass ratio of 1:1, one or more of 13 acid, 14 acid, 15 acid, 16 acid, 17 acid, 18 acid, preferably 16 acid, 17 acid, and 18 acid, in a mass ratio of 1:1:1.

[0012] Further, the high-pressure compression molding is performed after the above raw materials are uniformly mixed, the high-pressure compression has a pressure of 10-80 MPa, a pressure-increasing time of 3-10 s, a pressure-maintaining time of 5-20 s, and then a pressure-releasing time of 3-6 s.

[0013] Further, the aggregate is an inorganic substance that is easy to be compression molded, including but not limited to one or more of gypsum, cement, fine sand, calcium oxide, quicklime, magnesium oxide, and iron filings, the pore-forming agent is a soluble salt or sugar, including but not limited to calcium chloride, magnesium sulfate, magnesium chloride, sodium chloride, sodium bicarbonate, glucose, fructose, sucrose, and maltose, the slow-release carrier can be a small particulate substance with adsorption, including but not limited to one or more of activated carbon, biochar, carbon fiber, molecular sieve, bentonite, attapulgite, kaolin, montmorillonite, clay, and diatomite, and the adhesive can be at least one of acrylic resin, polyvinyl alcohol, and urea-formaldehyde resin.

[0014] According to the problems and needs of different water environments, corresponding functional ingredients are added when the above raw materials are mixed, and after compression molding, a slow-release composite carrying functionality is formed. In use, the soluble sugar or salt in the slow-release composite dissolves in the water body, forming a large number of pore structures in the composite, and at the same time, the stable composite structure is loosened, starting the slow release. In the process of continuous water infiltration, the pores increase and enlarge, and the slow-release carrier carrying the functional ingredients falls off and transfers to the water body, thereby achieving the slow release of the functional ingredients and adjusting the water environment.

[0015] Preferably, the aggregate is at least one of gypsum, cement, quicklime, and at least one of fine sand and iron filings, wherein the fine sand and iron filings have a particle size of 1-3 mm and a mass ratio of 30-40% in the aggregate.

[0016] The preparation method of the slow-release composite is characterized in that: the raw materials are uniformly mixed, and then high-pressure compression molding is performed, the pressure of the high-pressure compression is 10-80 MPa, the pressure increasing time is 3-10 s, the pressure maintaining time is 5-20 s, then pressure relief is performed, and the pressure relief time is 3-6 s.

[0017] Further preferably, the pressure of the high-pressure compression is 20-80 MPa, the pressure increasing time is 4-8 s, the pressure maintaining time is 10-15 s, then pressure relief is performed, and the pressure relief time is 4-6 s.

[0018] Most specifically, a preparation method of a slow-release composite for water treatment is characterized in that the following steps are performed:

[0019] Batching: 10-40 parts of aggregate, 2-5 parts of sodium sesquicarbonate, 10-60 parts of pore-forming agent, 10-40 parts of slow-release carrier, 5-20 parts of functional ingredient, 1-3 parts of low-melting-point organic matter, and 5-15 parts of adhesive are uniformly mixed with 1-3 parts of water, the aggregate is an inorganic substance that is easy to be compression molded, including but not limited to one or more of gypsum, cement, fine sand, calcium oxide, quicklime, magnesium oxide, and iron filings, the pore-forming agent is a soluble salt or sugar, including but not limited to calcium chloride, magnesium sulfate, magnesium chloride, sodium chloride, sodium bicarbonate, glucose, fructose, sucrose, and maltose, the slow-release carrier can be a small-particle substance with adsorption, including but not limited to one or more of activated carbon, biochar, carbon fiber, molecular sieve, bentonite, attapulgite, kaolin, montmorillonite, clay, and diatomite, the low-melting-point organic matter can be a composition of urea and benzoic acid in a mass ratio of 1:1, at least one of 13 acid, 14 acid, 15 acid, 16 acid, 17 acid, and 18 acid, and the adhesive can be at least one of acrylic resin, polyvinyl alcohol, and urea-formaldehyde resin;

[0020] Compression: the raw materials are uniformly mixed, and then high-pressure compression molding is performed, the pressure of the high-pressure compression is 10-80 MPa, the pressure increasing time is 3-10 s, the pressure maintaining time is 5-20 s, then pressure relief is performed, and the pressure relief time is 3-6 s.

[0021] In the preparation process, it is found that the slow release of the composite is difficult to control, and the prepared slow release composite is prone to problems such as rapid decomposition in water, failing to achieve slow release; or difficult to decompose, and the functional ingredients are difficult to release. Most importantly, when the functional ingredients are added, if the proportion of the functional ingredients is larger, the carrier forming is more difficult, and after forming, the carrier will cause faster decomposition in the water environment, resulting in faster slow release rate, and it is difficult to achieve slow release and adjust the water body.

[0022] Therefore, in the preparation process, by adding an organic matter with a melting point of 40-70 DEG C, and pressing under a very high pressure environment, the inorganic salt in the composite produces a certain lattice distortion, and the very high pressure in the pressing process will cause the pressing temperature to rise slightly, promoting the low-melting-point organic matter to form a molten state, uniformly infiltrating into the system, after the pressure relief is completed, the low-melting-point organic matter is reconverted into a solid, which cooperates with the adhesive to stabilize the overall structure of the composite, so that the load of the functional ingredients is significantly improved, and the slow release function of the composite is effectively ensured.

[0023] The present application has the following technical effects:

[0024] The slow release composite prepared by the present application has high strength, can slowly decompose in water, and the release speed is controllable. The functional ingredients loaded in the slow release composite are released to stabilize the concentration of microorganisms and trace elements in water body, and improve the quality of water environment. The load of the functional ingredients in the slow release composite prepared by the present application can reach 5%-30%, and the slow release period can be controlled within 10-100 days. Different functional ingredients and contents and different slow release periods can be selected according to the needs of different water environments to achieve the purpose of adjusting the water environment. The preparation method of the present application is simple, the cost is low, and the production can be scaled up. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The slow release effect of the slow release composite prepared in example 1 of the present application in water.

[0026] Figure 2 The slow release effect of the slow release composite prepared in example 1 of the present application in water.

[0027] Figure 3 The slow release effect of the slow release composite prepared in example 3 of the present application in water.

[0028] Figure 4 The slow release effect of the slow release composite prepared in example 3 of the present application in water. DETAILED DESCRIPTION

[0029] The application will be described in detail below by examples. It is necessary to point out here that the following examples are only used to further illustrate the application and cannot be understood as limiting the protection scope of the application. Those skilled in the art can make some non-essential improvements and adjustments to the application according to the above content of the application.

[0030] Example 1

[0031] A preparation method of a slow-release composite for water treatment is carried out in the following steps:

[0032] Ingredients: the aggregate is 20 parts of gypsum, 2 parts of sodium carbonate, 10 parts of glucose as a pore-forming agent, 20 parts of attapulgite as a slow-release carrier, 20 parts of lactic acid as a functional component, 3 parts of a low-melting-point organic substance, 15 parts of polyvinyl alcohol as an adhesive, and 2 parts of water, which are uniformly mixed; the low-melting-point organic substance is composed of urea and benzoic acid in a mass ratio of 1:1;

[0033] Pressing: after the above raw materials are uniformly mixed, high-pressure pressing is carried out for molding, the pressure of the high-pressure pressing is 10 MPa, the pressure rising time is 5 s, the pressure maintaining time is 20 s, and then pressure relief is carried out, the pressure relief time is 5 s.

[0034] The slow-release composite prepared in this example is shown in Figure 1 The prepared slow-release composite is soaked in water, and the weight change of the slow-release composite is recorded every day, as shown in Figure 2 The weight of the slow-release composite is 4.36 kg at the beginning, and changes to 2.80 kg at the 10th day, and the slow-release composite is completely decomposed at the 36th day after subsequent continuous statistics.

[0035] Example 2

[0036] A preparation method of a slow-release composite for water treatment is carried out in the following steps:

[0037] Ingredients: the aggregate is 28 parts of cement, 3 parts of sodium carbonate, 20 parts of calcium chloride as a pore-forming agent, 30 parts of bentonite as a slow-release carrier, 15 parts of lactic acid as a functional component, 2 parts of a low-melting-point organic substance, 6 parts of an adhesive, and 2 parts of water, which are uniformly mixed, the low-melting-point organic substance is composed of urea and benzoic acid in a mass ratio of 1:1, and the adhesive is acrylic resin;

[0038] Pressing: after the above raw materials are uniformly mixed, high-pressure pressing is carried out for molding, the pressure of the high-pressure pressing is 40 MPa, the pressure rising time is 5 s, the pressure maintaining time is 12 s, and then pressure relief is carried out, the pressure relief time is 5 s.

[0039] Comparative Example 1

[0040] Different from example 2, using urea 2 parts to replace the combination of urea and benzoic acid in example 2, the rest is consistent with example 1, as follows:

[0041] Ingredients: according to the mass fraction, the aggregate is 28 parts of cement, 3 parts of sodium carbonate, 20 parts of calcium chloride, 30 parts of bentonite, 15 parts of functional component lactic acid, 2 parts of low melting point organic matter, 6 parts of adhesive, 2 parts of water, mix uniformly, the low melting point organic matter is urea, and the adhesive can be acrylic resin;

[0042] Pressing: after the above raw materials are uniformly mixed, high pressure pressing is carried out, the pressure of the high pressure pressing is 40MPa, the pressure rising time is 5s, the pressure holding time is 12s, then pressure relief is carried out, and the pressure relief time is 5s.

[0043] Comparative example 2

[0044] Different from example 2, using benzoic acid 2 parts to replace the combination of urea and benzoic acid in example 2, the rest is consistent with example 1, as follows:

[0045] Ingredients: according to the mass fraction, the aggregate is 28 parts of cement, 3 parts of sodium carbonate, 20 parts of calcium chloride, 30 parts of bentonite, 15 parts of functional component lactic acid, 2 parts of low melting point organic matter, 6 parts of adhesive, 2 parts of water, mix uniformly, the low melting point organic matter is urea, and the adhesive can be acrylic resin;

[0046] Pressing: after the above raw materials are uniformly mixed, high pressure pressing is carried out, the pressure of the high pressure pressing is 40MPa, the pressure rising time is 5s, the pressure holding time is 12s, then pressure relief is carried out, and the pressure relief time is 5s.

[0047] It is found in the preparation process that the single urea and benzoic acid added into the system respectively cannot realize the function of the effective fixed composite structure in the application, in the water environment, the composite is quickly decomposed, and the decomposition is completed in 15 days, which greatly shortens the slow-release period, reduces the slow-release effect of the functional component, and obviously reduces the adjustment ability of the composite to the water environment.

[0048] Example 3

[0049] A preparation method of a slow-release composite for water treatment is carried out as follows:

[0050] Ingredients: according to the mass fraction, the aggregate is 28 parts of cement, and the zeolite powder with a particle size of 1-3 mm is composed of cement and zeolite powder with a particle size of 1-3 mm according to a mass ratio of 6.5:3.5, the soap ash is 3 parts, the pore forming agent is 20 parts of calcium chloride, the slow-release carrier is 30 parts of bentonite, the functional component lactic acid is 15 parts, the low-melting-point organic matter is 2 parts, the adhesive is 6 parts, and the water is 2 parts, which are uniformly mixed, the low-melting-point organic matter is composed of urea and benzoic acid according to a mass ratio of 1:1, and the adhesive can be acrylic resin;

[0051] Pressing: after the above raw materials are uniformly mixed, high-pressure pressing is performed, the pressure of the high-pressure pressing is 40 MPa, the pressure increasing time is 5 s, the pressure maintaining time is 12 s, then pressure relief is performed, and the pressure relief time is 5 s.

[0052] The slow-release composite prepared in this embodiment is placed in water for soaking, and the weight change of the slow-release composite is recorded every day, as shown in Figure 3 Figure 4 As shown, the weight of the slow-release composite is 3.72 kg at the beginning, and the weight changes to 3.17 kg at the 7th day, and the slow-release composite is completely decomposed at the 52nd day after subsequent continuous statistics.

[0053] Example 4

[0054] A preparation method of a slow-release composite for water treatment is performed in the following steps:

[0055] Ingredients: according to the mass fraction, the aggregate is 28 parts of cement, the soap ash is 3 parts, the pore forming agent is 20 parts of calcium chloride, the slow-release carrier is 30 parts of bentonite, the functional component lactic acid is 5 parts, the low-melting-point organic matter is 2 parts, the adhesive is 6 parts, and the water is 2 parts, which are uniformly mixed, the low-melting-point organic matter is composed of urea and benzoic acid according to a mass ratio of 1:1, and the adhesive can be acrylic resin;

[0056] Pressing: after the above raw materials are uniformly mixed, high-pressure pressing is performed, the pressure of the high-pressure pressing is 40 MPa, the pressure increasing time is 5 s, the pressure maintaining time is 12 s, then pressure relief is performed, and the pressure relief time is 5 s.

[0057] Example 5

[0058] A preparation method of a slow-release composite for water treatment is performed in the following steps:

[0059] Ingredients: according to the mass fraction, the aggregate is 28 parts of calcium sulfate, the soap ash is 3 parts, the pore forming agent is 20 parts of calcium chloride, the slow-release carrier is 30 parts of bentonite, the functional component lactic acid is 10 parts, the low-melting-point organic matter is 2 parts, the adhesive is 6 parts, and the water is 2 parts, which are uniformly mixed, the low-melting-point organic matter is composed of urea and benzoic acid according to a mass ratio of 1:1, and the adhesive can be acrylic resin; ​

[0060] Pressing: After the above raw materials are mixed uniformly, high-pressure pressing is performed, the pressure of the high-pressure pressing is 40 MPa, the pressure increasing time is 5 s, the pressure maintaining time is 12 s, then pressure relief is performed, the pressure relief time is 5 s.

[0061] Example 6

[0062] A preparation method of a slow-release composite for water treatment is performed according to the following steps:

[0063] Batching: according to the mass fraction, the aggregate is 28 parts of cement, the soda ash is 3 parts, the pore-forming agent is 20 parts of calcium chloride, the slow-release carrier is 30 parts of bentonite, the functional component lactic acid is 20 parts, the low-melting-point organic matter is 2 parts, the adhesive is 6 parts, and the water is 2 parts, which are uniformly mixed, the low-melting-point organic matter is composed of urea and benzoic acid in a mass ratio of 1:1, and the adhesive can be acrylic resin;

[0064] Pressing: After the above raw materials are mixed uniformly, high-pressure pressing is performed, the pressure of the high-pressure pressing is 40 MPa, the pressure increasing time is 5 s, the pressure maintaining time is 12 s, then pressure relief is performed, the pressure relief time is 5 s.

[0065] Example 7

[0066] A preparation method of a slow-release composite for water treatment is performed according to the following steps:

[0067] Batching: according to the mass fraction, the aggregate is 28 parts, which is composed of cement and fine sand with a particle size of 1-3 mm in a mass ratio of 6.5:3.5, the soda ash is 3 parts, the pore-forming agent is 20 parts of calcium chloride, the slow-release carrier is 30 parts of bentonite, the functional component Bacillus subtilis is 30 parts, the low-melting-point organic matter is 2 parts, the adhesive is 6 parts, and the water is 2 parts, which are uniformly mixed, the low-melting-point organic matter is composed of 16 acid, 17 acid and 18 acid in a mass ratio of 1:1:1, and the adhesive can be acrylic resin;

[0068] Pressing: After the above raw materials are mixed uniformly, high-pressure pressing is performed, the pressure of the high-pressure pressing is 40 MPa, the pressure increasing time is 5 s, the pressure maintaining time is 12 s, then pressure relief is performed, the pressure relief time is 5 s.

[0069] Example 8

[0070] A preparation method of a slow-release composite for water treatment is performed according to the following steps:

[0071] Ingredients: according to the mass fraction, the aggregate is 40 parts of cement, 5 parts of sodium carbonate, 60 parts of pore forming agent, which is composed of magnesium sulfate and fructose in a mass ratio of 1:1, the slow-release carrier is 40 parts of diatomite, the functional component is 30 parts of lactic acid bacteria, the low-melting organic matter is composed of 16 acid, 17 acid and 18 acid in a mass ratio of 1:1:1, the adhesive is 5 parts of acrylic resin, and the water is 3 parts, which are mixed uniformly;

[0072] Pressing: the mixed ingredients are subjected to high-pressure pressing molding, the pressure of the high-pressure pressing is 80 MPa, the pressure rising time is 3 s, the pressure maintaining time is 5 s, and then the pressure is released, and the pressure releasing time is 3 s.

[0073] The slow-release composite prepared in this example is subjected to slow-release test in water, and observation is performed every day, the slow-release speed is slow, and the slow-release is completely decomposed on the 98th day.

[0074] Example 9

[0075] A preparation method of a slow-release composite for water treatment is performed in the following steps:

[0076] Ingredients: according to the mass fraction, the aggregate is 10 parts of quicklime, 2 parts of sodium carbonate, 50 parts of pore forming agent, which is composed of sodium bicarbonate and glucose in a mass ratio of 1:1, the slow-release carrier is 10 parts of montmorillonite, the functional component is 20 parts of lactic acid bacteria, 1 part of 13 acid, the adhesive is 5 parts of urea-formaldehyde resin, and the water is 1 part, which are mixed uniformly;

[0077] Pressing: the mixed ingredients are subjected to high-pressure pressing molding, the pressure of the high-pressure pressing is 10 MPa, the pressure rising time is 10 s, the pressure maintaining time is 5 s, and then the pressure is released, and the pressure releasing time is 6 s.

[0078] The slow-release composite prepared in this scheme is subjected to slow-release test in water, the slow-release is fast, and the slow-release is completely decomposed on the 10th day.

[0079] By placing the slow-release composites prepared in each example in the same water environment, the weight change of the slow-release composite is recorded every 7 days, and the results are shown in Table 1.

[0080] Table 1: weight change of different slow-release composites in water

[0081]

[0082] From the above table, when the same proportion of functional components is loaded, a single low-melting organic matter is used in Comparative Example 1 and Comparative Example 2, and the prepared sustained-release composite is completely decomposed between 14-21 days, while the sustained-release composite prepared in Example 2 can be extended to 35-42 days. Secondly, on the basis of Example 2, Example 3 uses a composite skeleton material to replace a single skeleton material, and the sustained-release period is significantly prolonged. Finally, it can be seen that as the proportion of functional components increases, the sustained-release rate of the prepared sustained-release composite is accelerated, because the proportion of functional components increases, resulting in that the binding strength of the composite is inhibited to a certain extent, and the composite is more easily decomposed in water. However, in Example 8, under higher pressure, a combination of 16 acid-18 acid low-melting organic matter is selected, and the overall sustained-release rate is obviously alleviated.

[0083] In the preparation process, the functional components can be selected according to the needs of the water environment, which can be different microorganisms, or trace elements and other components required to improve the water body.

Claims

1. A slow-release complex for water treatment, characterized by: The raw materials of the slow-release composite include aggregate, sodium carbonate, pore-forming agent, slow-release carrier, low-melting organic matter with a melting point of 40-70℃, adhesive and water, which are mixed and pressed to obtain the slow-release composite, wherein the aggregate is 10-40 parts, the sodium carbonate is 2-5 parts, the pore-forming agent is 10-60 parts, the slow-release carrier is 10-40 parts, the low-melting organic matter is 1-3 parts, the adhesive is 5-15 parts, and the water is 1-3 parts, according to mass fraction; the low-melting organic matter includes one or more of a composition composed of urea and benzoic acid in a mass ratio of 1:1, 13 acid, 14 acid, 15 acid, 16 acid, 17 acid and 18 acid; the pore-forming agent is soluble salt or sugar; the mixing and pressing is to uniformly mix the raw materials and then perform high-pressure pressing, wherein the pressure of the high-pressure pressing is 10-80 MPa, the pressure increasing time is 3-10 s, the pressure maintaining time is 5-20 s, then pressure relief is performed, and the pressure relief time is 3-6 s.

2. The slow-release complex for water treatment according to claim 1, characterized by that: The aggregate includes one or more of gypsum, cement, fine sand, calcium oxide, quicklime, magnesium oxide and iron filings.

3. The slow release complex for water treatment as claimed in claim 2, wherein: The soluble salt or sugar includes one or more of calcium chloride, magnesium sulfate, magnesium chloride, sodium chloride, sodium bicarbonate, glucose, fructose, sucrose and maltose.

4. The slow-release complex for water treatment according to any one of claims 1 to 3, characterized in that: The slow-release carrier includes one or more of activated carbon, biochar, carbon fiber, molecular sieve, bentonite, attapulgite, kaolin, montmorillonite, clay and diatomite.

5. The slow-release complex for water treatment according to claim 4, characterized by that: The adhesive is at least one of acrylic resin, polyvinyl alcohol and urea-formaldehyde resin.

6. A method for the preparation of a slow release complex for water treatment, characterized by, The following steps are performed: The following steps are performed: The following steps are performed: The following steps are performed:

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