NL2019794B1 - Method and system for treating a residual flow from the cultivation of plants - Google Patents

Abstract

A method for treating a residual stream originating from growing plants in the land / or horticulture, the method comprising the steps of: providing the residual stream, wherein the residual stream comprises a concentration of crop protection agents; separating the residual stream into a permeate stream and a concentrate stream, wherein the concentrate stream contains at least substantially all crop protection means from the residual stream; draining the permeate stream; and recycling the concentrate stream for growing plants.

Description

Patent center

2019794

(21) Application number: 2019794 © Application submitted: October 24, 2017 @ Int. CL:

A01G 9/24 (2018.01) C02F 1/44 (2018.01)

@ Priority: (73) Patent holder (s): October 24, 2016 NL 2017666 Van der Ende Pumps B.V. in MAASDIJK. (Tl) Application registered: (72) Inventor (s): April 26, 2018 Lex van der Ende in MAASDIJK. Luuk Tetteroo in DELFT. (43) Application published: April 30, 2018 (74) Agent: (¢ 7) Patent granted: ir. P.J. Hylarides et al. In The Hague. September 11, 2018 (45) Patent issued: November 15, 2018

54) Method and system for treating a residual flow from the cultivation of plants ct) Method for treating a residual flow from the cultivation of plants in agriculture and / or horticulture, the method comprising the steps of:

- providing the residual flow, wherein the residual flow comprises a concentration of crop protection agents;

- separating the residual stream into a permeate stream and a concentrate stream, wherein the concentrate stream contains at least substantially all crop protection means from the residual stream;

- draining the permeate stream; and

- returning the concentrate stream for growing plants.

NL Bl 2019794

This patent has been granted regardless of the attached result of the research into the state of the art and written opinion. The patent corresponds to the documents originally submitted.

Method and system for treating a residual flow from the cultivation of plants

The present invention relates to a method for treating a residual flow from the cultivation of plants in agriculture and / or horticulture.

In agriculture and horticulture, plant protection products (GBM) are used to combat diseases, pests, weeds or organisms that are annoying or harmful. Such crop protection means can be supplied, for example, in addition to any nutrients, to the watering system in, for example, a greenhouse or similar building for growing plants, so that the plants can be efficiently provided with the necessary protection means.

In addition to a controlled supply of water for watering, the drainage flow of water after cultivation, in particular during cultivation in (greenhouse) horticulture, is also checked. Typically, in addition to a watering system for watering the plants, a greenhouse is provided with, for example, a drainage system for draining a residual flow from growing plants. This drain system can for instance be coupled to cultivation gutters or other suitable collecting means for collecting water. After any treatment of this residual flow, also referred to as purge flow, the residual flow is discharged, for example discharged into the surface water or into the sewer. This residual flow can for instance also comprise drain water, drainage water and filter rinsing water.

However, it is a disadvantage that crop protection agents and biocides are still present in that residual stream. In surface waters, high concentrations of the active substances of plant protection products and biocides are measured. This threatens flora and fauna and, moreover, surface water can be used for drinking water production. To counter this problem, it is known to purify the water to be discharged so that 95% of the plant protection products are removed. A commonly used method is to break down at least 95% of those crop protection agents from a residual stream.

It is an object of the present invention, in addition to other objects, to provide a simple, efficient and / or cost-effective method for treating a residual flow from the cultivation of plants in agriculture and / or horticulture.

This goal, in addition to other goals, is achieved by a method according to claim 1. More specifically, this goal, in addition to other goals, is achieved by a method for treating a residual flow from the cultivation of plants in agriculture and / or horticulture , the method comprising the steps of:

- providing the residual flow, wherein the residual flow comprises a concentration of crop protection agents;

- separating the residual stream into a permeate stream and a concentrate stream, wherein the concentrate stream contains at least substantially all crop protection means from the residual stream;

- draining the permeate stream; and

- returning the concentrate stream for growing plants.

According to the invention, the residual flow is effected in a stream with a high concentration of crop protection agents and a stream with a low concentration of crop protection agents. The stream with low concentration of crop protection agents, the permeate stream as mentioned above, can then be discharged, for example by discharging that stream into the surface water or into the sewer.

Typical active agents of crop protection agents are, for example, carbendazim, pymetrozine and Thiophanate methyl. It is noted that the invention according to a further embodiment also relates to the treatment of a residual stream which in addition to, or even instead of, plant protection products contains nutrients and / or pesticides. Such nutrients and / or pesticides, such as biocides, can be separated from the residual stream for recycling according to the invention.

To this end, the permeate stream preferably comprises virtually no crop protection agents, in particular the active substances thereof. According to a preferred embodiment, the concentrate stream for this purpose comprises at least 95% of the crop protection means from the residual stream. 95% of the crop protection agents from the residual stream are hereby removed from that stream, so that the permeate stream can be discharged. The same applies to any nutrients and / or pesticides in the residual flow. It is then advantageous if during separation the concentrate stream contains at least substantially all nutrients and / or pesticides such as biocides from the residual stream. Those nutrients and pesticides can then also be reused, as will be discussed more specifically later for the plant protection products.

According to the invention, the separated plant protection products are offered for reuse. The concentrate stream, which contains a high concentration of crop protection agents, is recirculated for this purpose for growing plants. The expensive and complicated step of breaking down and possibly separated discharges, i.e. without discharging them into, for example, the surface water, is then no longer necessary. The method therefore preferably further comprises the step of watering plants with the recycled concentrate stream, or at least the use of the recycled concentrate stream for watering. A preferred embodiment further comprises the step of providing a watering stream for watering plants from the recycled concentrate stream. The concentrate stream is then preferably supplied, in addition to, for example, clean (ground) water and any foodstuffs, to the watering system for providing a watering stream for growing the plants. The supply of crop protection agents and possibly nutrients and biocides as discussed above to the watering stream can then be adjusted in dependence on the amount of recycled crop protection agents and possibly nutrients and biocides to obtain a watering flow with a predetermined concentrations of pesticides and optionally nutrients and biocides. The watering stream is then preferably used for watering plants, preferably the plants from which the residual stream originates. In this way a more or less closed system is created with regard to the plant protection products.

According to a further embodiment of the method according to the invention, the step of separating comprises filtering the residual stream. Thus, the crop protection agents and any other substances can be separated from the residual flow in an efficient manner. The filter is herein preferably arranged for filtering out the crop protection means to the concentrate stream. To this end, the pores of the filter are preferably so small that the concentrate stream contains at least substantially all crop protection means, more preferably at least 95% of the crop protection means and any other substances from the residual stream.

In order to prevent the recycled stream containing the crop protection agents from containing too many unwanted salts such as, for example, sodium, which is unfavorable for cultivation, the slack of the separation preferably also comprises filtering the residual stream, the filter being adapted to allow passage of salts to the permeate stream. In contrast to conventional filters for processing salt-containing streams where the undesired salts are discharged into the concentrate stream, the filter according to the invention allows the salts to pass correctly, so that they essentially end up in the permeate stream. That stream can then be discharged as described above. The pore size of the filter is preferably chosen to be so large that salts can pass unimpeded. The method according to the invention is then extremely suitable for desalting a residual stream, such as a purge stream.

An efficient filtration is obtained if the filtering comprises a pressure-driven membrane process. An applied pressure, for example between 1 - 10 bar, forces the permeate through the membrane, while the concentrate is discharged. A suitable method is, for example, nanofiltration (pore size of about 10-50 nm at a pressure of 1 - 10 bar) or ultrafiltration (MWCO of 100 - 500 Dalton at a pressure of 1-5 bar). According to a preferred embodiment the filter pores are of the membrane are therefore between 10 and 50 nm.

To further reduce the concentration of crop protection agents in the permeate stream, a preferred embodiment of the method further comprises a second filtering step for filtering the permeate stream. The filter is herein preferably chosen such that the concentration of crop protection agents in the filtered permeate stream is virtually zero. Efficient filtering is possible if the second filtering step involves the use of an active carbon. This can be done very efficiently because this stream has already passed through a filter, preferably a nanofiltration membrane, and thus contains very few organic substances that are adsorbed by active carbon.

The invention further relates to a system for treating a residual flow from the cultivation of plants in agriculture and / or horticulture, wherein the system comprises an input, an output, a return and separating means, wherein the separating means are adapted to separating a residual stream presented at the input into a permeate stream and a concentrate stream, wherein the concentrate stream comprises at least substantially all crop protection means from the residual stream, and wherein the output is adapted to carry out the permeate stream and wherein the return is arranged for the recycling of the concentrate stream.

The system is preferably adapted to perform the method according to the invention as described above.

The invention further relates to a greenhouse for growing plants therein, provided with a watering system for watering the plants and a drainage system for discharging a residual flow from the cultivation of plants, wherein the greenhouse is provided with a system according to the invention, wherein the input is coupled to the drain system and wherein the supply is coupled to the watering system. A greenhouse is thus provided in which the crop protection agents can be reused efficiently.

The present invention is further illustrated with reference to the following figure and examples, which show a preferred embodiment of the method according to the invention, and are not intended to limit the scope of the invention in any way, wherein:

figure 1 shows a flow chart of an embodiment of the method according to the invention; figure 2 shows an alternative flow chart according to the invention.

Figure 1 schematically shows a system 100 for treating a residual flow 3 (also referred to as purge flow) from a greenhouse 1. The flow 3 comes from growing plants in the greenhouse 1 and is connected, for example, to a discharge system 11a of cultivation gutters 11 in which the plants 12 stand. The greenhouse 1 is furthermore provided with a watering system 13 for watering the plants 12.

The residual flow 3 is supplied via a pump 21 to a nanofilter 2 in which a membrane filter 23 is placed with a pore size of 40 nm in this example. The pump 21 is adapted to apply a pressure of approximately 5 bar. On the concentrate side, a valve 22 is provided, which controls the concentrate flow 4.

With the valve 22 and the pump 21, in particular by adjusting the pressure supplied by that pump 21, the permeate flow 5 and the concentrate flow 4 can be adjusted on the basis of the supplied flow 3. In this example, the filter is adjusted at a permeate production of 250 l / h, with a recovery of 15%, the concentrate flow thus being 1.415 l / h.

The plant protection products present in the residual flow 3 and preferably the nutrients will not pass through the membrane 23 and therefore end up in the concentrate flow 4. The concentrate flow 4 is returned to the greenhouse 1 for reuse of the crop protection agents and nutrients. In this example, the concentrate flow 4 is coupled via a mixing device 7 and a line 41 to the watering system 13 of the greenhouse 1.

However, the membrane 23 is so coarse that undesired salts can pass unhindered. Any salt in the purge stream is thus separated from the residual stream 3 in the permeate stream 5, so that the stream 4 definitely contains less unwanted salt for reuse.

Depending on the quantities of plant protection products and nutrients in the stream 4, additional plant protection products can be supplied via input 7a, additional nutrients via input and additional water via input 7c.

The permeate stream 5 is substantially (preferably <95%) free from crop protection agents. In order to effectively remove the last remaining crop protection agents, the permeate stream 5 is once again coupled to an activated carbon filter 6. The resulting stream 61 can then, for example, be discharged into the surface water.

Figure 2 shows a greenhouse 1 provided with a system 100a according to the invention. Unlike in the embodiment of Figure 1, in which the pump 21 of the filter 2 is directly connected to the drainage system 1a, the drainage system 1aa in this embodiment is connected with a pipe 81 to a water supply 8. A pipe 84 provides the mixing device 7 of water from the supply 8.

In particular when sodium is to be discharged, the pump 21 can be switched on so that water from the supply 8 is passed through the filter 2. A separation takes place there as discussed above. Relatively much sodium will therefore be discharged on the permeate side, while the concentrate stream 4, containing the crop protection agents and any other additives such as biocides and nutrients, is returned to the supply 8. Alternatively, the permeate stream 4 is directly coupled to the mixing device 7.

The operation of the invention will be further elucidated with reference to the following examples.

Example 1

Protocol

The test was performed using the following protocol, which ordered the subsequent steps of:

1. Make provision to store 4x a 4-inch membrane. Bin with storage fluid?

2. RO Nexus Mini (available as System Filter Nexus from Moor Filtertechniek) for the test

a. Nexus Mini equipped with 2 pressure tubes (instead of 4)

b. Replace block (s), so that only the upper pressure tube supplies permeate.

c. Empty the lower pressure tube, the upper pressure tube for the NF membranes to be tested

3. Create test water

a. Fill the container with 1,000 liters of tap water (at least 1 day in advance)

b. Add NaCl, ± 3 kg (is ± 1.4 liters)

c. Add Topsin M ultra, + 0.1 liter

d. Add Pymetrozine, + 0.1 kg

4. Prepare test setup

5. Check test water (just before testing with membranes)

a. Is the temperature close to ambient temperature? (Ideally 20 ° C)

b. Measure water temperature _____ ° C

c. Measure EC _____ mS / cm

6. Test the DOW Filmtec NE270-4040 membrane

a. Unpack the membrane and first drain the storage liquid

b. Place the membrane in the upper pressure tube

c. Adjust RO on a permeate production of 2501 / h

d. Adjust RO to a recovery of 15%, so concentrate 1.415 1 / h.

e. Measure water temperature

f. Measure EC permeate

g. Measure EC concentrate mS / cm mS / cm h, take 2x water sample permeate (lx 610, lx LC), code see table

i. Take 2x water sample concentrate (lx 610, lx LC), code see table

j. turn RO off, deflate system and set membrane to liquid

7. Test the DOW Filmtec NF90-4040 membrane

a. Unpack the membrane and first drain the storage liquid

b. Place the membrane in the upper pressure tube

c. Adjust RO on a permeate production of 2501 / h

d. Adjust RO to a recovery of 15%, so concentrate 1.415 1 / h.

e. Measure water temperature ° C

f. EC permeate measuring mS / cm

g. Measure EC concentrate mS / cm

h. 2x water sample take permeate (lx 610, lx LC), code see table

i. Take 2x water sample concentrate (lx 610, lx LC), code see table

j. turn RO off, deflate system and set membrane to liquid

8. Test the Hydranautics ESNA1-LF2-LD-4040 membrane

a. Unpack the membrane and first drain the storage fluid

b. Place the membrane in the upper pressure tube

c. Adjust RO on a permeate production of 250 1 / h

d. Adjust RO to a recovery of 15%, so concentrate 1.415 1 / h.

e. Measure water temperature _____ ° C

f. Measure EC permeate _____ mS / cm

g. Measure EC concentrate _____ mS / cm

h. 2x water sample take permeate (lx 610, lx LC), code see table

i. Take 2x water sample concentrate (lx 610, lx LC), code see table

j. turn RO off, deflate system and set membrane to liquid

The analyzes were performed on the following samples, with the membrane used or not used:

# Membrane Sample | Analysis 1 not applicable Test water LC ³ 2 not applicable Test water 610 ⁴ 3 DOWFilmtec ™ NF270-4040 NF270 per ⁵ LC 4 DOW Filmtec ™ NF270-4040 NF270 per 610 5 DOW Filmtec ™ NF270-4040 NF270 con ⁶ LC 6 DOW Filmtec ™ NF270-4040 NF270 con 610 7 DOWFilmtec ™ NF90-4040 NF90 per lc 8 DOWFilmtec ™ NF90-4040 NF90 per 610 9 DOWFilmtec ™ NF90-4040 NF90 con LC 10 DOWFilmtec ™ NF90-4040 NF90 con 610 11 Hydranautics ESNA1-LF2-LD-4040 ¹ ESNA1 per LC 12 Hydranautics ESNA1-LF2-LD-4040 ESNA1 per 610 13 Hydranautics ESNA1-LF2-LD-4040 ESNA1 con LC 14 Hydranautics ESNA1-LF2-LD-4040 ESNA1 con 610 15 CSM NE4040 ² CSMNE per LC 16 CSM NE4040 CSMNE per 610 17 CSM NE4040 CSMNE con LC 18 CSM NE4040 CSMNE con 610

Explanation terms:

¹ Available under the name Hydranautics ESNA1-LF2-LD-4040 ² Available under the name CSM-Saehan® Membranes NE-4040-40

Liquid Chromatography ⁴ Research code 610 of the Eurofins Agro laboratory for the analysis of main and trace elements.

'From: permeate ^ö con: Concentrate

Results

The results are shown in the table below:

I Test water NF27 0 per NF27 0 con NF90 per NF90 con ESN Already per ESN Al con CSM NE per CSM NE con Sample # I ² 4 6 8 10 12 14 16 18 pH - 8.3 8 8 8.1 8 8.2 7.7 8 8.1 EC mS / c m 4.3 2.5 4.6 0.2 5 0.2 5.1 3.5 4.5 NH 4 mg / l ⁰ 0 0 0 0 0 0 0 0 K. mg / l 7.8 0 3.9 0 7.8 0 7.8 3.9 3.9 After mg / l 848 503 940 28 1018 37 1087 710 917 Ca. mg / l 44 12 48 0 52 0 52 20 48 Mg mg / l 4.9 0 7.3 0 7.3 0 7.3 0 7.3 NO3 mg / l I 12 19 12 6.2 19 12 12 19 12 Cl mg / l 1294 752 1418 39 1535 50 1542 1088 1376 S mg / l ¹⁹ 0 35 6.4 48 0 51 9.6 51 HCO3 mg / l 134 31 153 0 159 0 159 49 146 P mg / l ° 0 0 0 0 0 0 0 0 Fe pg / l 11 0 11 0 17 0 22 0 17 Mn pg / l r 0 0 0 11 0 5.5 0 0 Zn pg / l I ¹³ 26 13 0 13 0 13 46 13 B Mg / 1 30 30 30 23 32 29 36 32 31 Cu pg / l ° 0 0 0 0 0 0 0 0 Mo. pg / l ° 0 0 0 0 0 0 0 0 Si mg / l ¹⁴ 0.8 1.1 0 1.4 0 1.4 1.1 1.1 TDS mg / l 2377, ⁵ 1328, 4 2631, 0 87.9 2860 6 107.4 2932, 4 1912, 2 2575, 0 Hairiness ° D 7.3 1.7 8.4 0.0 8.9 0.0 8.9 2.8 8.4 Sample # 1 3 5 7 9 11 13 15 17 Carbendazi mg / k you 0.022 1.4 0 1.3 0 1.3 0.074 1.3

m g Pymetrozine mg / k g 17 1 20 0.5 20 0.6 20 3 20 Thiophanate -methyl mg / k g 13 0.11 15 0.056 15 0.077 16 0.31 17

The results are subject to measurement errors. Nevertheless, the test gives a good picture of the operation, which is summarized in the table below:

Membrane NaCl rejection Carbendazim rejection Pymetrozine rejection DOW Filmtec NF270-4040 41% 98% 94% DOW Filmtec NF90-4040 97% 100% 97% Hydranautics ESNA1-LF2- LD-4040 96% 100% 96% CSM NE4040 16% 94% 82%

From the above it can be concluded that in particular the DOW Filmtec NF270-4040 and CSM NE4040 with the low NaCl rejection (resulting in high concentration of these salts in the permeate) and high rejection values for the carbendazim and pymetrozine are suitable for the use according to the invention.

Example 2

The second example corresponds to a large extent to the first example, with the difference that a residual flow from a breeder is used as the test water. The composition of this residual stream has been analyzed as samples 1 and 2, see the table below.

The analyzes were performed on the following samples, with the membrane used or not used:

# Membrane Sample Analysis

1 not applicable Test water LC ³ 2 not applicable Test water 610 ⁴ 3 DOWFilmtec ™ NF270-4040 ' NF270 per ⁵ LC 4 DOWFilmtec ™ NF270-4040 NF270 per 610 5 DOWFilmtec ™ NF270-4040 NF270 con ⁶ LC 6 DOWFilmtec ™ NF270-4040 NF270 con 610 7 CSM NE4040 ² CSMNE per LC 8 CSM NE4040 CSMNE per 610 9 CSM NE4040 CSMNE con LC 10 CSM NE4040 CSMNE con 610

¹ Available under the name DOW Filmtec ™ NF270-4040 ² Available under the name CSM-Saehan® Membranes NE-4040-40 ³ Liquid Chromatography ⁴ Research code 610 from the Eurofins Agro laboratory for the analysis of main and trace elements.

⁵ a: ⁶ permeate con: Concentrate

Results

The results are shown in the table below:

Test water NF27 0 per NF27 0 con Straight tion CSMN E per CSMN E con Straight tion Sample # 2 4 6 8 10 pH - 5.9 6 5.9 6.1 5.9 EC mS / c m 3.9 1.9 4.3 51% 2 4.2 49% NH 4 mg / l 0 0 0 1.8 0 K. mg / l 262 274 262 -5% 285 250 -9% After mg / l 67 69 67 -3% 76 67 -13% Ca. mg / l 409 92 469 78% 92 457 78% Mg mg / l 134 7.3 158 95% 9.7 153 93%

NO3 mg / l 1631 930 1773 43% 986 1730 40% Cl mg / l 35 14 39 60% 21 43 40% S mg / l 208 0 253 100% 0 253 100% HCO3 mg / l 0 0 0 0 0 P mg / l 32 0 38 100% 2.2 37 93% Fe pg / i 385 0 447 100% 0 419 100% Mn pg / 1 368 55 429 85% 60 418 84% Zn pg / J 634 98 719 85% 105 719 83% B Pg / 1 1016 962 1016 5% 973 995 4% Cu Mg / 1 70 6.4 76 91% 6.4 76 91% Mo. pg / l 86 0 106 100% 0 106 100% Si mg / l 5.1 9.7 5.3 -90% 4.2 5.1 18% TDS mg / l 2795 5 1405, 0 3077, 3 50% 1487.1 3007.9 47% Hairiness ° D 87.8 14.5 101.7 83% 15.0 98.8 83% Sample # 1 3 5 7 9 Carbendazi m mg / kg 0.21 0.083 0.21 60% 0.17 19% Pymetrozine mg / kg 0.65 0.038 0.68 94% 0.12 0.71 82% Thiophanate -methyl mg / kg 0.37 0.12 0.34 68% 0.34 0.35 8%

The results are subject to measurement errors. For example, negative values were measured for certain rejections. Also, with sample 9, no carbendazim was measured in the concentrate. Nevertheless, the test gives a good picture of the operation, which is summarized in the table below:

Membrane NaCl rejection Carbendazim rejection Pymetrozine rejection Filmtec NF270-4040 41% 98% 90% CSM NE4040-40 16% 94% 70%

The NaCl rejections are relatively low again, while the rejection values for the carbendazim and pymetrozine are again relatively high. It can also be seen that the rejection values for the nutrients, for example P & NO ₃ , are very high. They can therefore also be reused efficiently.

The present invention is not limited to the embodiments shown, but also extends to other embodiments, which fall within the scope of the appended claims.

Claims (11)

Conclusions A method for treating a residual flow from the cultivation of plants in agriculture and / or horticulture, the method comprising the steps of: - providing the residual flow, wherein the residual flow comprises a concentration of crop protection agents; - separating the residual stream into a permeate stream and a concentrate stream, wherein the concentrate stream contains at least substantially all crop protection means from the residual stream; - draining the permeate stream; and - returning the concentrate stream for growing plants. A method according to claim 1, wherein the concentrate stream contains at least 95% of the crop protection agents from the residual stream. The method of claim 1 or 2, further comprising the steps of providing a watering stream for watering plants from the recycled concentrate stream and watering plants with the watering stream. Method according to at least one of the preceding claims, wherein the step of separating comprises filtering the residual flow, wherein the filter is adapted to filter out the crop protection means to the concentrate flow. A method according to at least one of the preceding claims, wherein the step of separating comprises filtering the residual stream, the filter being adapted to pass salts to the permeate stream. The method of claim 4 or 5, wherein the filtering comprises a pressure driven membrane process. The method according to at least one of claims 4-6, wherein the filter pores of the membrane are between 10 and 50 nm. A method according to at least one of the preceding claims, further comprising a second filtering step for filtering the permeate stream, wherein the concentration of crop protection agents in the filtered permeate stream is substantially zero. The method of claim 8, wherein the second filtering step comprises the use of an activated carbon. 10. System for treating a residual flow from the cultivation of plants in agriculture and / or horticulture, in particular for carrying out the method according to at least one of the preceding claims, wherein the system is an input, an output , comprises a return and separating means, wherein the separating means are adapted to separate a residual flow presented at the inlet into a permeate stream and a concentrate stream, wherein the concentrate stream comprises at least substantially all crop protection means from the residual stream, and wherein the outlet is adapted to executing the permeate stream and wherein the recycle is adapted to recycle the concentrate stream. A greenhouse for growing plants therein, provided with a watering system for watering the plants and a drainage system for draining a residual flow from growing plants, wherein the greenhouse is provided with a system according to claim 10, wherein the input is coupled to the drain system and where the supply is coupled to the watering system. Aguur1