RU2636468C1 - Method of producing concentrated hewitt nutritional solution - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method involves dissolving mineral salts in distilled water. Herewith the components containing calcium and magnesium are used in an amount less than the Hewitt's formulation, so that when the concentrate is subsequently diluted n-times with tap water of medium hardness, the concentration of calcium and magnesium ions corresponds to the Hewitt norm. The precipitation of calcium phosphates is prevented by acidifying the concentrate to a pH of 2.0-2.2 by adding hydrochloric and/or sulfuric acid and potassium phosphate alone in an effective amount. The concentrated nutrient solution is prepared by mixing the calculated amounts of mother liquors of mineral salts containing Hewitt nutrient solution components.

EFFECT: simplification of the Hewitt nutrient solution.

3 cl, 1 dwg, 2 tbl, 1 ex

Description

The invention relates to biotechnology and agriculture and can be used in hydroponic and greenhouse methods for growing plants, in floriculture, growing vegetables in household plots, etc.

Mineral substances involved in plant nutrition are subdivided into macro- and microelements. The first - nitrogen, potassium, phosphorus, sulfur, calcium, magnesium - are the main ones. Their influence on the vital activity and development of plant organisms is favorable and very diverse. The second group of elements - iron, boron, copper, zinc, manganese, molybdenum, cobalt and a number of others - are also required, but in small quantities.

Famous concentrated nutrient solution Flora Series - complex fertilizers for hydroponics and land (http://floragrow.ru/products/flora-series.html). This concentrate cannot be stored as a single solution; when merged, an insoluble precipitate is formed; therefore, the so-called “principle of three vials” with solution components is used, which introduces additional difficulties, especially when feeding plants by irrigation. Flora Series is not a universal tool, for its use use complex tables by plant species and by application dates. In addition, the widespread use of the Flora Series is limited by the high cost of the concentrate.

A known Hewitt nutrient solution containing N, P, K, Ca, Mg, S, Fe, Cu, Zn, Mn, B, Mo in calculated quantities, widely used in scientific research, as well as in the hydroponic method of growing plants. The ratio of elements was obtained empirically (Hewitt, 1966) and, according to various authors cited by Cooper (1988), Windsor & Schwarz (1990) (see Nutrient Solutions for Hydroponic Systems. Libia I. Trejo-Téllez and Fernando C. Gumez- Merino Colegio de Postgraduados, Montecillo, Texcoco, State of Mexico, Mexico, 2012), is one of the most successful for most higher plants. The nutrient solution contains calcium and magnesium - important components that affect the physicochemical state of plants. A lack of magnesium leads to the destruction of chlorophyll, and a deficiency of calcium causes damage to the point of growth of roots and aerial organs.

A Hewitt solution is prepared by dissolving the required amount of salts in distilled water. The preparation of a solution in large quantities outside the laboratory is a very costly and time-consuming process. Despite the effectiveness for most plants, Hewitt's nutrient solution, due to the complexity of its preparation and the relatively high cost, is rarely used on an agro-industrial scale.

An object of the invention is to simplify the process of preparing a Hewitt nutrient solution and a significant reduction in its cost.

The problem is solved by preparing a highly concentrated nutrient solution, designed for dilution with ordinary tap water in a predetermined ratio. A method of preparing such a solution involves dissolving in distilled water mineral salts containing all macro- and micronutrients according to Hewitt's recipe. Unlike the standard procedure, components containing calcium and magnesium are used in an amount less than the Hewitt recipe so that, with subsequent n-fold dilution of the concentrate with medium-hard tap water, the concentration of calcium and magnesium ions corresponds to the Hewitt norm. In this case, it is likely that at high concentrations in the solution water-insoluble salts are formed, primarily calcium phosphate, which precipitates. To prevent this phenomenon, the concentrate is acidified to pH = 2.0 ... 2.2.

The acidity of the solution can be increased in various ways. For our purposes, it is preferable to add small amounts of hydrochloric and / or sulfuric acid and monosubstituted potassium phosphate.

In a specific implementation of the method according to the invention, a nutrient medium concentrate intended to produce a Hewitt formula may be prepared by draining the calculated amounts of the mother liquor of the necessary salts with the addition of acidified distilled water.

A low pH and a low content of calcium and magnesium ions in the concentrate prevents the formation of calcium precipitate. The concentrate can be stored under normal conditions for a long time, up to a year or more. To prepare a standard Hewitt nutrient solution, the concentrate is diluted with tap water and the pH of the solution is adjusted to 5 ... 6.5, which is optimal for most plants. Concentrate, unlike a normal nutrient solution, can be conveniently transported in the required quantities to the place of use.

The use of a concentrated medium simplifies the preparation of large quantities of nutrient solution and can significantly reduce the cost of the consumer product needed for hydroponics, fertilizing and watering various agricultural plants. The cost of the final product (Hewitt's nutrient solution) can be reduced by 10 or more times. The economic benefits consist of replacing an expensive distillate with cheap tap water, reducing the amount of reagents needed, since some of them are added together with diluent water, from the convenience of preparation at the place of use, and from reducing transportation costs.

Example

It is required to prepare a concentrated solution, when diluted with ordinary drinking water of medium hardness in a ratio of 1:20, a nutrient solution is obtained according to the Hewitt recipe. Calculation of the composition of the concentrate, which will be diluted 20 times:

Table 1

In this case, part of calcium nitrate, magnesium sulfate, some trace elements will be introduced with water-diluent. Calculations show that in this particular case, the following ingredients are required to prepare the claimed highly concentrated Hewitt solution:

table 2

Accounting for the quantitative content of elements that are reduced in concentrate and will be added to the nutrient solution when diluted with tap water can be carried out according to the maximum allowable amount (MPC) provided by the sanitary rules and regulations of SanPiN 2.1.4.1074-01 “Drinking water”. The greatest contribution to tap water comes from calcium and magnesium, the salt content of which determines the hardness of the water. According to SanPiN, the total hardness of drinking water is up to 10 Mg-equiv. / L. Medium hardness water contains from 4 to 8 Mg-eq / l hardness salts (calcium and magnesium). More accurate accounting can be carried out by chemical analysis of the water supplied to the water supply system of the region where the concentrate is diluted. Methods for determining the hardness of drinking water, including calcium and magnesium, are known and set by the standard GOST 31954-2012.

The effectiveness of a Hewitt nutrient solution depends on the acidity of the medium. In the graphs of FIG. 1 vertically shows the availability of various nutrients for plants depending on the acidity of the pH (according to CANNA.com, source http://www.canna-ru.com/). From these data and from a number of other sources it follows that when diluting the concentrated Hewitt nutrient solution according to the invention with tap water n times (to the working concentration), its acidity should be brought to pH = 5.5 ... 6.0. The technical result of the invention is to simplify the process of preparing a Hewitt nutrient solution and a significant reduction in its cost, which makes it available for widespread use in hydroponics, in greenhouse vegetable growing, and in irrigated agriculture.

Claims (3)

1. A method of preparing a concentrated Hewitt nutrient solution, comprising dissolving mineral salts in distilled water, characterized in that the components containing calcium and magnesium are used in an amount less than the Hewitt formula, so that with subsequent n-fold dilution of the tap concentrate with water of medium hardness, the concentration of calcium and magnesium ions corresponded to the Hewitt norm, while preventing the precipitation of calcium phosphates, acidifying the concentrate to pH = 2.0-2.2. 2. The method according to claim 1, characterized in that the acidification of the concentrate is carried out by adding hydrochloric and / or sulfuric acid and monosubstituted potassium phosphate in an effective amount. 3. The method according to claim 1, characterized in that the concentrated nutrient solution is prepared by mixing calculated amounts of mother liquors of mineral salts containing the components of a Hewitt nutrient solution.

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