Disclosure of Invention
Therefore, the invention needs to provide a method for purifying and processing quartz sand for a petroleum fracturing propping agent, and aims to solve the problem that impurities in the quartz sand cannot be effectively removed in the prior art, so that the service performance of the quartz sand as the fracturing propping agent is poor.
The technical scheme is as follows:
a method for purifying and processing quartz sand for petroleum fracturing propping agent comprises the following steps:
s100, carrying out classified screening and impurity filtering treatment on the natural quartz sand raw material to obtain a natural quartz sand crude product;
s200, scrubbing the natural quartz sand coarse product subjected to classified screening and impurity filtering treatment;
s300, carrying out graded desliming treatment on the natural quartz sand coarse product after scrubbing treatment;
s400, reselecting the natural quartz sand crude product subjected to graded desliming treatment to obtain quartz refined sand;
s500, carrying out magnetic separation and impurity removal on the quartz refined sand obtained after the gravity separation to obtain quartz sand high-intensity magnetic separation tailings;
s600, carrying out color separation or flotation treatment on the quartz sand high-intensity magnetic separation tailings obtained after the magnetic separation and impurity removal to obtain a quartz sand finished product for the petroleum fracturing propping agent.
The method for purifying and processing the quartz sand for the petroleum fracturing propping agent is mainly used for removing impurities and purifying the quartz sand serving as the fracturing propping agent so as to remove various impurities in the quartz sand. Specifically, firstly, natural quartz sand raw materials are subjected to classified screening and impurity filtering treatment to remove large gravels, fine sand and soil; then, scrubbing the crude product of the natural quartz sand, and further dissociating to remove fine mud and iron impurities adhered to the surface of the quartz sand; then, carrying out graded desliming treatment on the crude product of the natural quartz sand, and further removing fine mud and wastewater mixed in the crude product of the natural quartz sand to obtain cleaner quartz sand; and then reselecting the quartz sand, thereby removing the heavy mineral impurities, and obtaining the quartz refined sand. Then, carrying out magnetic separation and impurity removal treatment on the quartz refined sand, thereby further removing the included strong magnetic minerals and weak magnetic minerals and obtaining the quartz sand strong magnetic tailings; and finally, performing color separation or flotation treatment on the quartz sand high-intensity magnetic separation tailings, so that low-intensity mineral impurities such as feldspar, rock debris and the like which are mixed can be removed, thus obtaining a quartz sand finished product with the breakage rate meeting the requirements of the fracturing propping agent, ensuring that all impurities in the quartz sand are removed cleanly and thoroughly, ensuring the service performance of the quartz sand as the fracturing propping agent, and improving the permeability and yield increasing capability of the hydraulic fracturing technology in a low-permeability oil field.
The technical solution of the present application is further described below:
in one embodiment, in the step S100 of performing classified screening and impurity filtering on the natural quartz sand raw material, the natural quartz sand raw material is firstly passed through a 10-mesh sieve to filter out large gravels, so as to complete primary filtration; and then, fine sand and soil are further filtered by a sieve of 20 meshes to 140 meshes, and secondary filtration is completed.
In one embodiment, in the step S200, in the scrubbing treatment of the coarse natural quartz sand product after the classifying, screening and impurity filtering treatment, the raw natural quartz sand material is put into a scrubbing machine for pulping and scrubbing, so that fine mud and iron impurities on the surface of the raw natural quartz sand material are dissociated; wherein the scrubbing concentration is 50-70%, and the scrubbing time is 5-20 min.
In one embodiment, in the step S400, the natural quartz sand coarse product after the graded desliming treatment is reselected, specifically, the natural quartz sand coarse product is put into a spiral chute, heavy minerals are separated from quartz sand by the action of gravity and centrifugal force of a rotational flow, and the heavy minerals are directly discharged to obtain quartz concentrate.
In one embodiment, in the step S500, magnetic separation and impurity removal are performed on the quartz refined sand obtained after heavy separation, specifically, a low-intensity magnetic separator is firstly used to perform a first separation treatment on the quartz refined sand to remove strong magnetic minerals; and then, carrying out secondary sorting treatment on the quartz refined sand by using a strong magnetic separator to remove weakly magnetic minerals so as to obtain the quartz sand strong magnetic separation tailings.
In one embodiment, in the step S600, in the flotation treatment of the quartz sand high-intensity magnetic separation tailings obtained after the magnetic separation and impurity removal, the quartz sand high-intensity magnetic separation tailings are put into a flotation machine, and meanwhile, a collecting agent and an inhibitor are added into ore pulp, and low-intensity impurity minerals such as feldspar and rock debris are removed by a reverse flotation method, so that a quartz sand finished product with qualified breakage rate is obtained; the collector is prepared from a collector A and a collector B according to the mass ratio of 1.0: 0.5-3.0, and the amount is 500-2000 g/t; the collector A can be at least one of lauryl amine and coconut alkyl primary amine, and the collector B can be at least one of sodium petroleum sulfonate, sodium dodecyl sulfonate and sodium oleate; the inhibitor is sodium hexametaphosphate, and the amount of the inhibitor is 0-100 g/t; the pH value of the ore pulp is 2-3.
In one embodiment, in the step S600, in the color separation treatment of the quartz sand high-intensity magnetic separation tailings obtained after the magnetic separation and impurity removal, the quartz sand high-intensity magnetic separation tailings are firstly dehydrated and dried, and then the dried quartz sand high-intensity magnetic separation tailings are put into a color separator for separation treatment.
In one embodiment, in the step S600, after the quartz sand high-intensity magnetic separation tailings subjected to magnetic separation and impurity removal are subjected to color separation treatment to obtain a finished quartz sand product, the method further comprises screening the finished quartz sand product to obtain products with different particle sizes, such as 10-20 meshes, 20-40 meshes, 30-50 meshes, 40-60 meshes, 50-70 meshes, 70-140 meshes, and the like; or, after the step S600, performing flotation treatment on the quartz sand high-intensity magnetic separation tailings subjected to magnetic separation and impurity removal to obtain a quartz sand finished product, and then screening, dehydrating and drying the quartz sand finished product to obtain products with different particle sizes of 10-20 meshes, 20-40 meshes, 30-50 meshes, 40-60 meshes, 50-70 meshes, 70-140 meshes and the like.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and the detailed description. It should be understood that the detailed description and specific examples, while indicating the scope of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
It will be understood that when an element is referred to as being "secured to," "disposed on" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present; the specific manner of fixedly connecting one element to another element can be implemented by the prior art, and will not be described herein, and preferably, a screw-threaded connection is used.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
As shown in fig. 1, a process flow chart of a method for purifying and processing quartz sand for a petroleum fracturing proppant shown in an embodiment of the present application specifically includes the following steps:
s100, carrying out classified screening and impurity filtering treatment on the natural quartz sand raw material to obtain a natural quartz sand crude product;
s200, scrubbing the natural quartz sand coarse product subjected to classified screening and impurity filtering treatment;
s300, carrying out graded desliming treatment on the natural quartz sand coarse product after scrubbing treatment;
s400, reselecting the natural quartz sand crude product subjected to graded desliming treatment to obtain quartz refined sand;
s500, carrying out magnetic separation and impurity removal on the quartz refined sand obtained after the gravity separation to obtain quartz sand high-intensity magnetic separation tailings;
s600, carrying out color separation or flotation treatment on the quartz sand high-intensity magnetic separation tailings obtained after the magnetic separation and impurity removal to obtain a qualified quartz sand finished product for the fracturing propping agent.
The method for purifying and processing the quartz sand for the petroleum fracturing propping agent is mainly used for removing impurities and purifying the quartz sand serving as the fracturing propping agent so as to remove various impurities in the quartz sand. Specifically, firstly, natural quartz sand raw materials are subjected to classified screening and impurity filtering treatment to remove large gravels, fine sand and soil; then, scrubbing the crude product of the natural quartz sand, and further dissociating to remove fine mud and iron impurities adhered to the surface of the quartz sand; then, carrying out graded desliming treatment on the crude product of the natural quartz sand, and further removing fine mud and wastewater mixed in the crude product of the natural quartz sand to obtain cleaner quartz sand; and then reselecting the quartz sand, thereby removing heavy mineral impurities and obtaining the quartz fine sand. Then, carrying out magnetic separation and impurity removal treatment on the quartz refined sand, thereby further removing the included strong magnetic minerals and weak magnetic minerals and obtaining the quartz sand strong magnetic tailings; and finally, performing color separation or flotation treatment on the quartz sand high-intensity magnetic separation tailings, so that low-intensity mineral impurities such as feldspar, rock debris and the like which are mixed can be removed, the clean and thorough removal of various impurities in the quartz sand can be ensured, the service performance of the quartz sand as a fracturing propping agent is ensured, a quartz sand finished product with the breakage rate meeting the requirement of the fracturing propping agent is obtained, and the capability of promoting the permeability and increasing the yield of a hydraulic fracturing technology in a low-permeability oil field is improved.
It should be noted that the raw material of the natural quartz sand of the present invention is a natural quartz sand formed through weathering, transportation, erosion, etc., wherein the particles of the natural quartz sand are round and have a smaller particle size than those of general quartz rock ores, and according to the geological conditions of the area, impurities such as large gravel, soil, iron impurities, feldspar, rock debris, etc. are included in the quartz sand, so that an effective filtering and purifying process method needs to be adopted to specifically remove the above-mentioned various impurities in the quartz sand to ensure the purifying effect.
Specifically, in one embodiment, in the step S100, the natural quartz sand raw material is subjected to classification screening and impurity filtering treatment to obtain a natural quartz sand crude product, and the natural quartz sand raw material is first filtered through a 10-mesh screen to remove large gravels, thereby completing primary filtration; and then, fine sand and soil are further filtered by a sieve of 20 meshes to 140 meshes, and secondary filtration is completed. Therefore, large gravels, small-particle-size gravels and soil in the natural quartz sand raw material can be removed in sequence in a grading and screening mode.
It should be noted that, depending on the structure and the particle size of the raw material of the natural quartz sand, other mesh screens may be used for the classified filtration in other embodiments, and all of them are within the protection scope of the present application.
In the step S200, in the scrubbing treatment of the coarse natural quartz sand product after the grading screening and impurity filtering treatment, the coarse natural quartz sand product is put into a scrubbing machine for pulping and scrubbing, so that fine mud and iron impurities on the surface of the coarse natural quartz sand product are dissociated; wherein the scrubbing concentration is 50-70%, and the scrubbing time is 5-20 min. It can be understood that the scrubbing machine has the effects that through stirring, the mutual friction among the quartz sand particles, the side wall of the machine body and the quartz sand particles can achieve high-frequency and multiple scrubbing, stubborn fine mud and iron impurities adhered to the surfaces of the quartz sand particles can be effectively scrubbed, fallen and removed, and further, a natural quartz sand coarse product with a clean appearance is obtained. Preferably, the scouring concentration of pulping and scouring the crude product of the natural quartz sand is 60%, and the scouring time is 10 min. Under the condition, the quartz sand is scrubbed, so that the scrubbing effect and the scrubbing efficiency can be considered, and the economic efficiency of the purification operation is improved.
In the step S400, the natural quartz sand coarse product after the graded desliming treatment is reselected, specifically, the natural quartz sand coarse product is put into a spiral chute, heavy minerals are separated from the quartz sand by the action of gravity and centrifugal force of a rotational flow, and the heavy minerals are directly discharged to obtain quartz refined sand. Through adopting the spiral chute to handle quartz sand, can effectively get rid of all kinds of heavy mineral impurity.
In addition, in the step S500, magnetic separation and impurity removal are performed on the quartz refined sand obtained after heavy separation, specifically, a low-intensity magnetic separator is firstly adopted to perform primary separation treatment on the quartz refined sand, so as to remove strong-magnetic minerals; and then, carrying out secondary sorting treatment on the quartz refined sand by using a strong magnetic separator to remove weakly magnetic minerals so as to obtain the quartz sand strong magnetic separation tailings. Therefore, the strong magnetic mineral impurities and the weak magnetic mineral impurities can be removed in a targeted manner through the weak magnetic separator and the strong magnetic separator, the impurity content in the quartz sand is greatly reduced, and the performance of the quartz sand as a fracturing propping agent is improved.
In the step S600, in the flotation treatment of the quartz sand high-intensity magnetic separation tailings obtained after the magnetic separation and impurity removal, the quartz sand high-intensity magnetic separation tailings are put into a flotation machine, a collecting combined agent and an inhibitor are added into ore pulp, and low-strength impurity minerals such as feldspar and rock debris are removed by a reverse flotation method to obtain a quartz sand finished product with qualified breakage rate; the collecting combined agent is prepared from a collecting agent A and a collecting agent B according to the mass ratio of 1.0: 0.5-3.0, and the amount is 500-2000 g/t; the collector A can be at least one of lauryl amine and coconut alkyl primary amine, and the collector B can be at least one of sodium petroleum sulfonate, sodium dodecyl sulfonate and sodium oleate; the inhibitor is sodium hexametaphosphate, and the amount of the inhibitor is 0-100 g/t; the PH of the ore pulp is 2-3.
In the step S600, in the color separation treatment of the quartz sand high-intensity magnetic separation tailings obtained after the magnetic separation and impurity removal, the quartz sand high-intensity magnetic separation tailings are firstly dehydrated and dried, and then the dried quartz sand high-intensity magnetic separation tailings are put into a color separator for separation treatment.
In addition, on the basis of any of the above embodiments, after the step S600, performing color separation treatment on the quartz sand high-intensity magnetic separation tailings subjected to magnetic separation and impurity removal to obtain a quartz sand finished product, screening the quartz sand finished product to obtain products with different particle sizes, such as 10-20 meshes, 20-40 meshes, 30-50 meshes, 40-60 meshes, 50-70 meshes, 70-140 meshes, and the like; or, in the step S600, after the quartz sand strong magnetic separation tailings subjected to the magnetic separation and impurity removal are subjected to flotation treatment to obtain a quartz sand finished product, the method further comprises the steps of screening and dehydrating the quartz sand finished product, and drying the quartz sand finished product to obtain products with different particle sizes, such as 10-20 meshes, 20-40 meshes, 30-50 meshes, 40-60 meshes, 50-70 meshes, 70-140 meshes and the like. Therefore, through sorting and screening, the qualified quartz sand for the fracturing propping agent with different grain sizes can be obtained, and the method is suitable for different markets and production requirements.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.