Online adjusting and processing system and method for abnormal working conditions of long-distance pipeline slurry concentration system

Abstract

The invention discloses an abnormal working condition online adjusting and processing system of a long-distance pipeline conveying slurry concentration system. The abnormal working condition online adjusting and processing system comprises an upstream incoming material pipeline, a feeding collection box is arranged below an outlet of the upstream feeding pipeline; an emergency pipeline with the tail end leading to the ore pulp distribution box is further communicated with the upstream feeding pipeline between the feeding concentration meter and the flow meter, and an emergency pipeline switch electric valve is arranged on the emergency pipeline; a thickener is arranged below the outlet end of the feeding collection box; the lower end of the thickener is communicated with an inlet of the underflow pump through an underflow pump inlet pipeline; an outlet of the underflow pump is communicated with an underflow pump outlet pipeline, the tail end of the underflow pump outlet pipeline is divided into two paths, one path is a self-circulation pipeline leading to the feeding collection box, and the other path is a normal pulp conveying pipeline leading to the pulp distribution box; the invention further discloses a corresponding processing method. Through diagnostic analysis and targeted treatment of abnormal working conditions of the concentration system, safe and stable operation of the concentration system is ensured, rake pressing of the thickener can be effectively avoided, and investment is saved.

Description

Technical Field

[0001] The present invention relates to an online regulating and processing device and an online disposal method for abnormal working conditions of a concentrating system for conveying slurry in a pipeline, which can be applied to the setting of a slurry concentrating system without a spare thickener and under conditions of large process fluctuations, and belongs to the technical field of slurry concentrating. Background Art

[0002] Slurry concentration is the core process unit of slurry pipeline transportation. Its function is to concentrate the concentrate or tailings slurry with lower concentration into a high-concentration slurry that meets the requirements of pipeline transportation process. The concentration effect of slurry is directly related to the safety and stability of slurry transportation. Therefore, actual production has very high requirements for the stable operation of the concentration system. Usually, the concentration system controls the slurry concentration by adjusting the speed and frequency of the underflow pump, and at the same time, the concentration is detected by the ultrasonic concentration meter on the underflow pipe of the thickener. The control of concentration has high requirements for upstream incoming materials and concentration meters. Once the upstream working conditions fluctuate greatly, it is very easy to cause the concentration of the concentrated underflow to become uncontrollable, which in turn causes problems such as unstable underflow pump delivery flow and inaccurate concentration meter measurement.

[0003] At present, there is no systematic and scientific method for dealing with the above problems, which often requires the operator to have very rich field experience. The transported slurry often has the characteristics of high specific gravity of mineral powder and high concentration. If the above problems are not dealt with in time, it is easy to cause a series of problems such as the concentration of the concentrated slurry not meeting the transportation index, the thickener pressure rake, and the siltation and blockage of the underflow pipe. If there is no backup thickening system, it will directly lead to the serious consequence of on-site shutdown. The present invention uses an online diagnostic device for abnormal working conditions of a slurry thickening system, and realizes the diagnosis and analysis of abnormal working conditions of the thickening system by detecting the pressure and flow of the inlet and outlet pipelines. It also realizes the processing of various working conditions by online switching of relevant pipelines and valves in the device and control of the underflow pump, thereby ensuring the safe and stable operation of the thickening system. Summary of the invention

[0004] In view of the problems or defects in the prior art, the present invention aims to solve the problem that the slurry thickening system in the prior art is prone to the problem that once the upstream operating conditions fluctuate greatly, the concentrated underflow concentration will easily become uncontrollable, thereby causing the underflow pump to have unstable delivery flow, inaccurate measurement of the concentration meter, the concentrated slurry concentration not meeting the delivery indicators, and the thickener pressure rake and underflow pipe siltation and blockage.

[0005] In order to achieve the above-mentioned purpose, the present invention relates to an online regulation and processing system for abnormal working conditions of a long-distance pipeline slurry concentration system, comprising an upstream feed pipeline; the upstream feed pipeline is sequentially provided with a feed concentration meter, a flow meter, and a feed flow regulating valve; a feed collection box is provided below the outlet of the upstream feed pipeline; the upstream feed pipeline between the feed concentration meter and the flow meter is also connected with an emergency pipeline whose end leads to a slurry distribution box, and an emergency pipeline switch electric valve is provided on the emergency pipeline; a thickener is provided below the outlet end of the feed collection box; the lower end of the thickener is connected with the inlet of the underflow pump through an underflow pump inlet pipeline; the outlet of the underflow pump is connected with the underflow pump outlet pipeline, and the end of the underflow pump outlet pipeline is divided into two paths, one of which is a self-circulation pipeline leading to the feed collection box, and the other is a normal slurry pipeline leading to the slurry distribution box; a self-circulation pipeline switch electric valve is provided on the self-circulation pipeline, and a normal slurry pipeline switch electric valve is provided on the normal slurry pipeline;

[0006] Two pipelines are arranged at the lower end of the slurry distribution box, one pipeline leads to the emergency accident mixing tank, and the other pipeline leads to the normal slurry mixing tank; both pipelines are provided with distribution box electric valves.

[0007] Furthermore, the upstream incoming material pipeline may be a single pipeline or multiple pipelines, and the upstream incoming material may be incoming from one place or from multiple places.

[0008] Furthermore, the underflow pump is a centrifugal slurry pump with remote and local variable frequency speed regulation functions.

[0009] Furthermore, a high-pressure flushing water system is arranged at the inlet of the underflow pump, and the opening and closing of the valve can be controlled online through the flushing water switch electric valve, and vent pipes are arranged at the inlet and outlet of the underflow pump.

[0010] Furthermore, the vent pipe is connected to a ditch or a waste liquid pool.

[0011] Furthermore, the feed flow regulating valve, self-circulation pipeline switch electric valve, normal slurry pipeline switch electric valve, flushing water switch electric valve, and distribution box electric valve all have remote operation and local operation functions, and the concentration meter, flow meter and underflow pump pressure transmitter have remote and local display functions.

[0012] Another aspect of the present invention is to provide an online adjustment and processing method for abnormal working conditions of a long-distance pipeline slurry concentration system, including an online slurry adjustment method for overfeed protection, which specifically includes the following steps:

[0013] Step S1: During the operation of the online adjustment and treatment system for abnormal working conditions of the long-distance pipeline slurry concentration system, the feed flow rate and concentration are detected: after the upstream feed pipe receives the feed, the feed concentration C is recorded by the concentration meter and flow meter on the feed pipe. 0(mass concentration, %) and slurry volume V 0 (m 3 / h), and the incoming dry ore quantity Q is obtained 0 (t / h):

[0014]

[0015] Among them, ρ s is the density of the concentrated mineral, t / h;

[0016] Step S2: the amount of dry ore Q 0 Maximum processing capacity of thickener Q max In comparison, when Q 0 >1.25Q max , it is judged as "high feed amount";

[0017] Among them, the maximum processing capacity of the thickener is Q max The value of is determined as follows: the maximum amount of dry ore fed without causing the thickener rake torque to rise to 80% of the limit value at the maximum delivery flow of the underflow pump;

[0018] Step S3: When the system determines that the feed volume is high, the electric valve of the emergency pipeline is opened, and the slurry is transported to the emergency mixing tank through the slurry distribution box. At the same time, the flow regulating valve is adjusted to ensure that the dry ore volume Q entering the slurry collection box is 0 Less than Q max , and then adjust the frequency of the underflow pump to make the concentration of the concentrated underflow slightly higher than the normal conveying concentration, and then send it to the slurry distribution box. This part of the slurry is mixed with the slurry that enters the emergency accident mixing tank after diversion in the tank body to be prepared into a slurry that meets the conveying requirements;

[0019] Step S4, until Q is detected 0 <1.25Q max After that, the electric valve (7) is closed to stop the overcurrent protection of the concentration system.

[0020] Furthermore, the method for online adjustment and processing of abnormal working conditions of a long-distance pipeline slurry concentration system is characterized in that the method for preparing the slurry that meets the transportation requirements in step S3 is specifically:

[0021] (1) Detect the upstream material quantity Q 0 And the actual amount of slurry entering the thickener system Q 1 , adjust the frequency of the underflow pump and detect the outlet pressure of the underflow pump at the same time, so that the delivery pressure remains at P out , this pressure is higher than the normal slurry delivery pressure, where P out Calculate according to formula (2)-(5):

[0022] P out =ρ底 ×g×H 1 +P 损 (2)

[0023]

[0024] Among them, H 1 is the height difference from the underflow pump outlet to the slurry distribution box, m; P 损 is the loss along the pipeline, MPa; ρ 底 is the density of the underflow slurry, kg / m 3 ; C min The minimum concentration of slurry that meets the transportation conditions, %; ρ 底 is the density of the mineral, kg / m 3 ; g is the acceleration due to gravity, m / s 2 , ρ s is the density of the concentrated mineral, t / h.

[0025] Another aspect of the present invention is to provide an online adjustment and processing method for abnormal working conditions of a long-distance pipeline slurry concentration system, including an online slurry adjustment method for insufficient feed concentration and a pipeline blockage emergency protection method, which specifically includes the following steps:

[0026] Step S1. During the operation of the online adjustment and treatment system for abnormal conditions of the long-distance pipeline slurry concentration system, the feed rate Q 0 Rated processing capacity of thickener Q 额 Compare, when Qs in <0.7Q 额 , it is judged as "feed amount is too low";

[0027] Step S2. Observe the outlet pressure P of the underflow pump out , when the outlet pressure P out Less than the minimum preset pressure P 0 When the concentration is high, the frequency of the underflow pump is lowered, and the electric valve of the self-circulation pipeline is opened to start the self-circulation of the concentrated underflow;

[0028] The minimum preset pressure is calculated by the following formula:

[0029] P 0 =ρ min ×g×H 1 +P 损 (6)

[0030] Among them, ρ min The slurry density corresponding to the minimum allowable conveying concentration slurry, kg / m 3 , H 1 is the height difference from the underflow pump outlet to the slurry distribution box, m;

[0031] Step S3: After the self-circulation starts, the outlet pressure of the underflow pump will continue to increase. At this time, the rise in the outlet pressure of the underflow pump is continuously observed;

[0032] Step S4: When the outlet pressure of the underflow pump reaches the maximum preset pressure P 1 When the pressure at the outlet of the underflow pump starts to drop gradually, open the electric valve of the normal slurry delivery pipeline and increase the frequency of the underflow pump at the same time. 0 When , repeat step S1;

[0033] The maximum preset pressure is calculated by formula (7):

[0034] P 1 =ρ max ×g×H 2 +P 损 (7)

[0035] Among them, ρ max The slurry density corresponding to the maximum allowable conveying concentration slurry, kg / m 3 ;H 2 is the height difference from the underflow pump to the feed collection box, m; P 损 is the friction loss along the self-circulating pipeline, MPa.

[0036] Another aspect of the present invention is to provide an online adjustment and processing method for abnormal working conditions of a long-distance pipeline slurry concentration system, including: a pipeline blockage emergency protection method, specifically including the following steps:

[0037] Step S1, during the operation of the online regulation and treatment system for abnormal working conditions of the long-distance pipeline slurry concentration system, when the outlet pressure of the underflow pump rises to the limit pressure P due to a sudden change in the upstream process or due to improper on-site operation, max , and at the same time observed that the liquid level in the mixing tank rose slowly or did not rise, which was judged as a "pipeline blockage warning";

[0038] Furthermore, the ultimate pressure P in the present invention is max Calculate using formula (8):

[0039] P max =1.25×ρ max ×g×H 1 +P 损 (8)

[0040] Step S2: When the “pipeline blockage warning” appears, immediately increase the frequency of the underflow pump. If the pressure gradually drops to P out <P max At the same time, if the liquid level in the mixing tank rises normally, the warning is lifted. If the outlet pressure of the underflow pump continues to rise, follow step S3.

[0041] Step S3, the outlet pressure of the underflow pump continues to rise, indicating that the pipeline slurry concentration is too high or the mineral powder is seriously blocked at the corner. The underflow pump head alone can no longer push the pipeline slurry to move. At this time, open the flushing water switch electric valve to backwash the underflow pump and the thickener, open the vent pipe to release the slurry, and open the valve to deliver the slurry to the emergency accident mixing tank. The slurry delivery time is adjusted according to the on-site processing time;

[0042] Step S4, after the pipeline is dredged, the slurry is prepared to meet the transportation requirements.

[0043] Compared with the prior art, the present invention has the following effects:

[0044] (1) The online adjustment and processing system and method for abnormal operating conditions of a long-distance pipeline slurry thickening system of the present invention avoids the problem that a set of backup thickening systems is required in the traditional thickening process to avoid the raking accident of the thickener through reasonable pipeline and equipment design and processing logic design under different situations. This method occupies a lot of space and requires a lot of investment. At the same time, the backup system is often not fully utilized. There is no need to set up a backup system and the thickener can also be effectively avoided from being raked, saving investment.

[0045] (2) The online adjustment and processing system and method for abnormal operating conditions of a long-distance pipeline slurry concentration system of the present invention collects system operation data in real time by installing sensors such as concentration meters, flow meters and pressure transmitters at key nodes. All key valves and equipment can be remotely controlled and operated on-site to ensure effective control under different circumstances. It can promptly detect and diagnose abnormal conditions in the system, such as overfeed, underfeed or pipeline blockage, so as to take measures in advance to avoid system failures. It has better ability to cope with abnormal conditions. Through diagnostic analysis and targeted treatment of abnormal conditions of the concentration system, it ensures safe and stable operation of the concentration system.

[0046] (3) The online adjustment and processing system and method for abnormal operating conditions of the long-distance pipeline slurry concentration system of the present invention is provided with an emergency pipeline, an emergency mixing tank and a flushing water system, and realizes rapid switching through an electric valve; when an abnormal situation occurs, the slurry can be quickly transferred to the emergency mixing tank to prevent system overload or pipeline blockage, thereby ensuring the continuity of production and the safety of equipment.

[0047] (4) The online adjustment and treatment system and method for abnormal operating conditions of the long-distance pipeline slurry concentration system of the present invention regularly flushes the underflow pump and pipeline through a self-circulating pipeline and a flushing water system; effectively prevents slurry deposition inside the pipeline and equipment, reduces maintenance frequency, extends equipment service life, and reduces maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1It is a schematic diagram of the overall system structure of a preferred embodiment of the present invention;

[0049] Figure 2 is a processing logic flow chart of a preferred embodiment of the present invention;

[0050] In the figure: 1-feed collection box, 2-thickener, 3-underflow pump, 4-slurry distribution box, 5-emergency accident mixing tank, 6-normal slurry mixing tank, 7-emergency pipeline switch electric valve, 8-feed concentration meter, 9-flow meter, 10-feed flow regulating valve, 11-self-circulation pipeline switch electric valve, 12-normal slurry pipeline switch electric valve, 13-underflow pump pressure transmitter, 14-flushing water switch electric valve, 15-upstream incoming pipeline, 16-emergency pipeline, 17-underflow pump inlet pipeline, 18-underflow pump outlet pipeline, 19-distribution box electric valve, 20-normal slurry pipeline, 21-self-circulation pipeline. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0052] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0053] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0054] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0055] In order to solve the problem of preventing and controlling accelerated flow in a slurry conveying pipeline in the prior art, the present invention provides a slurry pipeline energy dissipation orifice plate and an energy dissipation device used therein.

[0056] In view of the deficiencies in the control of the concentration system under abnormal conditions and the risks faced, this embodiment proposes an online adjustment and processing system and an online disposal method for abnormal conditions of a concentration system for pipeline transportation of slurry. The abnormal conditions of the concentration system are diagnosed and analyzed by detecting the pressure and flow of the inlet and outlet pipelines, and the various conditions are handled by online switching of relevant pipelines and valves in the device and control of the underflow pump, thereby ensuring the safe and stable operation of the concentration system.

[0057] The online adjustment and processing system for abnormal working conditions of the pipeline slurry concentration system includes an online slurry adjustment device for overfeed protection, an online slurry adjustment device for insufficient feed concentration, and a pipeline blockage emergency protection device. It can be used to adjust online the abnormal working conditions that may occur in the production process, including: excessive feed, insufficient feed, and excessive underflow concentration, to avoid production accidents such as rake pressure and pipe blockage while ensuring stable and continuous production.

[0058] An online slurry mixing device for overfeed protection is provided, wherein a feed collection box is provided, the inlet of which is connected to an upstream feed pipeline, a flow regulating valve and a flow meter are provided at the inlet (in some preferred embodiments, more sensor types, such as temperature sensors and vibration sensors, can also be introduced to more comprehensively monitor the operating status of the equipment, thereby discovering potential problems earlier), and another pipeline is provided on the upstream feed pipeline to connect to an emergency protection stirring tank;

[0059] As a preferred solution, the upstream incoming material pipeline can be one pipeline or multiple pipelines, and the upstream incoming material can be incoming from one place or multiple places;

[0060] As a preferred solution, the flow control valve has the functions of remote operation and local operation, and the concentration meter and flow meter have remote and local display functions, which are conventional monitoring equipment for slurry flow;

[0061] The inadequate feed concentration online slurry adjusting device, the bottom of the thickener is connected to the underflow pump, a pressure transmitter is arranged on the underflow pump discharge pipeline, the underflow pump discharge pipeline is connected to the slurry distribution box, an electric valve is arranged below the slurry distribution box, the valve opening and closing can be adjusted remotely and locally, and the online real-time slurry distribution function is realized, the underflow pump discharge pipeline is also provided with a circulation pipeline connected to the collection box inlet, and the underflow pump discharge pipeline is provided with an electric valve to control the pipeline opening and closing;

[0062] As a preferred solution, the underflow pump is a centrifugal slurry pump. The centrifugal slurry pump is designed with full consideration of the need to transport abrasive slurries. Wear-resistant materials, such as high-chromium alloy, are used to enhance the wear resistance of flow-through parts, thereby extending the service life of the pump and reducing the maintenance frequency. It has remote and local frequency conversion speed regulation functions. The centrifugal slurry pump is designed with a detachable pump casing and wearing parts for easy replacement and maintenance; the pressure transmitter has online and remote pressure display functions;

[0063] The pipeline blockage emergency protection device is provided with high-pressure flushing water at the pump inlet, the valve opening and closing can be controlled online through the electric valve, and the vent pipe is provided at the pump inlet and outlet.

[0064] In particular, the pump outlet vent pipe is arranged at the bend of the horizontal pipeline and the vertical pipeline, and the vent pipe is connected to the ditch or waste liquid pool;

[0065] In some preferred embodiments, key components of the system, such as thickeners, underflow pumps, distribution boxes and mixing tanks, are designed as independent modular units. Each modular unit is equipped with standardized interfaces to ensure that it can be seamlessly integrated into the existing system or replaced when necessary; vibration damping devices are also added to the pipe supports and joints to effectively control vibration and protect the pipe system.

[0066] As another aspect of the embodiment of the present invention, it also relates to an online adjustment and processing method for abnormal operating conditions of a concentration system for pipeline slurry transportation, comprising the following steps:

[0067] (1) When the amount of incoming material is too large, the over-incoming material protection is carried out and the slurry is adjusted online at the same time. The specific process includes the following points:

[0068] After the upstream incoming material pipeline receives the material, the concentration meter and flow meter on the incoming material pipeline record the incoming material concentration C 0 (mass concentration, %) and V 0 (m 3 / h), and get the incoming dry ore quantity Q (t / h):

[0069]

[0070] Among them, ρ s is the density of the concentrated mineral, kg / m 3 ;

[0071] Step S2: the amount of dry ore Q 0 Maximum processing capacity of thickener Q max In comparison, when Q 0 >1.25Q max , it is judged as "high feed amount",

[0072] Furthermore, in the present invention, the maximum processing capacity of the thickener Q max The value of is determined as follows: the maximum feed amount that does not cause the thickener rake torque value to rise to 80% of the limit value at the maximum delivery flow of the underflow pump;

[0073] Step S3: When the system determines that the feed volume is high, the electric valve (7) of the emergency pipeline is opened, and the slurry is transported to the emergency mixing tank (5) through the slurry distribution box (4). At the same time, the flow control valve (9) is adjusted to ensure that the dry ore volume Q entering the slurry collection box (1) is 0 Less than Q max , then adjust the frequency of the underflow pump (3) so that the concentration of the concentrated underflow is (slightly) higher than the normal conveying concentration, and then convey it to the slurry distribution box (4). This part of the slurry is mixed with the slurry entering the emergency accident stirring tank (5) after diversion in the tank body to be prepared into a slurry that meets the conveying requirements;

[0074] Furthermore, the steps of preparing the slurry to meet the transportation requirements are as follows:

[0075] (1) Detect the upstream material quantity Q 0 And the actual amount of slurry entering the thickener system Q 1 ,

[0076] (2) Adjust the frequency of the underflow pump and detect the outlet pressure of the underflow pump at the same time to keep the delivery pressure at P out , this pressure is slightly higher than the normal slurry delivery pressure, where P out Calculate according to formula (2)-(5):

[0077] P out =ρ 底 ×g×H 1 +P 损 (2)

[0078]

[0079] Among them, H 1 is the height difference from the underflow pump outlet to the slurry distribution box, m; P 损 is the loss along the pipeline, MPa; ρ 底 is the density of the underflow slurry, kg / m 3 ; C min The minimum concentration of slurry that meets the transportation conditions, %; ρ 底 is the density of the mineral, kg / m 3 ; g is the acceleration due to gravity, m / s 2 ;

[0080] Step S4, until Q is detected 0 <Q max Finally, close the electric valve of the emergency pipeline and stop the overcurrent protection and slurry preparation process of the concentration system.

[0081] (2) When the upstream material flow is insufficient, the concentration of the insufficient material is adjusted online. The main steps are:

[0082] Step S1: Feeding amount Q 0 Rated processing capacity of thickener Q 额 Compare, such as Qs in <0.7Q 额 , it is judged as "feed amount is too low";

[0083] Step S2: Observe the outlet pressure P of the underflow pump out , when the outlet pressure P out Less than the minimum preset pressure P 0 When the bottom flow pump frequency is lowered, the electric valve of the circulation pipeline is opened to allow the concentrated bottom flow to start self-circulation.

[0084] Furthermore, the minimum preset pressure in the present invention is calculated by the following formula:

[0085] P 0 =ρ min ×g×H 1 +P 损 (6)

[0086] Among them, ρ min The slurry density corresponding to the minimum allowable conveying concentration slurry, kg / m 3 ;

[0087] Step S3, after the self-circulation starts, the outlet pressure of the underflow pump 3 will continue to rise, and at this time, the rise in the outlet pressure of the underflow pump is continuously observed;

[0088] Step S4: When the outlet pressure of the underflow pump 3 reaches the maximum preset pressure P 1 When the outlet pressure of the underflow pump starts to drop gradually, open the electric valve to the qualified mixing tank and increase the frequency of the underflow pump at the same time. 0 , repeat step S1.

[0089] Specifically, the maximum preset pressure can be calculated by formula (7):

[0090] P 1 =ρ max ×g×H 2 +P 损 (7)

[0091] Among them, ρ max The slurry density corresponding to the maximum allowable conveying concentration slurry, kg / m 3 ;H 2 is the height difference from the underflow pump to the feed collection box, m; P 损 is the friction loss along the self-circulating pipeline, MPa.

[0092] (3) When the underflow pipeline is blocked due to large fluctuations upstream or improper on-site operation, emergency protection measures for pipeline blockage are carried out, which mainly include the following steps:

[0093] Step S1: When the outlet pressure of the underflow pump 3 rises to the limit pressure P due to a sudden change in the upstream process or due to improper on-site operation, the outlet pressure of the underflow pump 3 rises to the limit pressure P max , and at the same time observed that the liquid level in the mixing tank rose slowly or did not rise, which was judged as a "pipeline blockage warning";

[0094] Specifically, the ultimate pressure P max It can be calculated by formula (8):

[0095] P max =1.25×ρ max ×g×H 1 +P 损 (8)

[0096] Step S2: After the "pipeline blockage warning" appears, immediately increase the frequency of the underflow pump 3. If the pressure gradually drops to P<Pmax during the process, and the liquid level in the mixing tank rises normally, the warning is lifted. If the pump outlet pressure continues to rise, follow step S3.

[0097] Step S3, the outlet pressure of the underflow pump 3 continues to rise, indicating that the slurry concentration in the pipeline is too high or the mineral powder is seriously blocked at the corner. The lift of the underflow pump 3 alone cannot push the slurry in the pipeline to move. At this time, the flushing water switch electric valve 14 is opened to backwash the underflow pump 3 and the thickener, and the vent pipe is opened to release the slurry. At the same time, the emergency pipeline valve is opened to deliver the slurry to the emergency accident mixing tank. The slurry delivery time is adjusted according to the on-site processing time;

[0098] Step S4, after the pipeline is dredged, the slurry is prepared according to the above slurry preparation ideas.

[0099] Specific case 1:

[0100] Taking the concentration process of long-distance pipeline transportation of iron ore concentrate in a certain area of ​​Liaoning as an example, the feed concentration is 33%-37%, and the total feed volume is about 1200m 3 / h. According to the process requirements, the required concentrated slurry concentration is 60%-65%. The thickener used is a 45m center-driven thickener with a maximum processing capacity of about 640Mt / a.

[0101] Use attached Figure 1 The online regulating and processing device for abnormal working condition of the thickening system of the pipeline transporting slurry and the attached Figure 2 The emergency response process is shown.

[0102] Due to the failure of upstream process equipment, the ore flow rate of the concentration system was greatly reduced. The feed concentration was 35% and the flow rate was 800m 3 / h. Step 1: First, the incoming material quantity Qs i Compared with the rated processing capacity of the thickener, due to Q 0 <0.7Q 额 , it is judged as "feed volume is too low", and at the same time, the bottom flow pump outlet pressure Pout = 0.4MPa, which is less than the preset minimum P min At this time, the frequency of the underflow pump is lowered, and the electric valve of the circulation pipeline is opened at the same time, so that the concentrated underflow begins to circulate. After the slurry circulation, the outlet pressure of the underflow pump is observed to rise gradually. When the outlet pressure of the underflow pump rises to P out =0.5MPa, close the underflow circulation, increase the frequency of the underflow pump, and continue to feed the slurry into the mixing tank. In the case of insufficient concentrated feed, the slurry feeding process will gradually reduce the outlet pressure of the underflow pump. When the outlet pressure drops to the preset minimum P 1 After that, the above process is repeated. The operation steps of the above working condition are shown in Table 1. The concentration of the slurry obtained by concentration according to the above steps is about 65%, which meets the actual production needs.

[0103] Table 1 Emergency treatment steps for insufficient flow conditions

[0104]

[0105] Specific case 2:

[0106] Taking this thickening system as an example, during a period of time, the incoming material volume was too high due to fluctuations in the upstream process. After testing, the hourly incoming ore volume Q = 860t / h, which is higher than the maximum processing capacity of the thickener. If it is not processed, it will cause iron ore precipitation and accumulation in the thickener, and eventually lead to a rake pressure accident. After the abnormal fluctuation of the incoming material volume occurs, the excessive incoming material protection of the present invention is activated, and online slurry adjustment is performed at the same time. First, the emergency pipeline valve is opened to divert the incoming material. Part of the slurry is directly transported to the emergency accident mixing tank through the emergency pipeline. At the same time, the feed flow regulating valve is adjusted to stabilize the amount of material entering the thickener at around the rated processing volume. After the diversion is completed, the slurry is adjusted. First, the frequency of the underflow pump is adjusted so that the outlet pressure P of the underflow pump is adjusted. out = 0.61MPa, the concentrated slurry is also transported to the emergency accident mixing tank to mix with the diverted slurry. When the upstream material volume returns to normal, the operation of this working condition ends. After testing, the concentration of the concentrated slurry prepared by this method is about 62%, which meets the requirements of slurry transportation. The operating steps of the above working condition are shown in Table 2.

[0107] Table 2 Treatment steps for excessive feed

[0108]

[0109] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An online adjustment and processing system for abnormal working conditions of a long-distance pipeline slurry concentration system, characterized in that: The invention comprises an upstream material supply pipeline (15); the upstream material supply pipeline (15) is provided with a feed concentration meter (8), a flow meter (9), and a feed flow regulating valve (10) in sequence; a feed collection box (1) is provided below the outlet of the upstream material supply pipeline (15); the upstream material supply pipeline between the feed concentration meter (8) and the flow meter (9) is also connected to an emergency pipeline (16) whose end leads to a slurry distribution box (4); the emergency pipeline (16) is provided with an emergency pipeline switch electric valve (7); a thickener (2) is provided below the outlet end of the feed collection box (1); The lower end of the concentrator (2) is connected to the inlet of the underflow pump (3) through the underflow pump inlet pipeline (17); the outlet of the underflow pump (3) is connected to the underflow pump outlet pipeline (18), and the end of the underflow pump outlet pipeline (18) is divided into two paths, one of which is a self-circulating pipeline (19) leading to the feed collection box (1), and the other is a normal slurry delivery pipeline (20) leading to the slurry distribution box (4); the self-circulating pipeline (19) is provided with a self-circulating pipeline switch electric valve (11), and the normal slurry delivery pipeline (20) is provided with a normal slurry delivery pipeline switch electric valve (12); Two pipelines are arranged at the lower end of the slurry distribution box (4), one pipeline leading to the emergency accident stirring tank (5) and the other pipeline leading to the normal slurry conveying stirring tank (6); both pipelines are provided with distribution box electric valves (19).

2. The abnormal condition online adjustment and processing system of the long-distance pipeline slurry concentration system according to claim 1 is characterized in that: The upstream incoming material pipeline can be a single pipeline or multiple pipelines, and the upstream incoming material can be incoming from one place or from multiple places.

3. The online adjustment and processing system for abnormal operating conditions of a long-distance pipeline slurry concentration system according to claim 1 is characterized in that: The underflow pump (3) is a centrifugal slurry pump having remote and local frequency conversion speed regulation functions.

4. The abnormal condition online adjustment and processing system of the long-distance pipeline slurry concentration system according to claim 1 is characterized in that: A high-pressure flushing water system is provided at the inlet of the underflow pump (3), and the opening and closing of the valve can be controlled online through the flushing water switch electric valve (14). Vent pipes are provided at the inlet and outlet of the underflow pump (3).

5. The online adjustment and processing system for abnormal operating conditions of a long-distance pipeline slurry concentration system according to claim 4 is characterized in that: The vent pipe is connected to a ditch or a waste liquid pool.

6. The online adjustment and processing system for abnormal operating conditions of a long-distance pipeline slurry concentration system according to claim 4 is characterized in that: The feed flow regulating valve (10), the self-circulating pipeline switch electric valve (11), the normal slurry pipeline switch electric valve (12), the flushing water switch electric valve (14), and the distribution box electric valve (19) all have the functions of remote operation and local operation, and the concentration meter (8), flow meter (9) and underflow pump pressure transmitter (13) have remote and local display functions.

7. A method for online adjustment and processing of abnormal operating conditions of a long-distance pipeline slurry concentration system, characterized in that: The invention comprises an online slurry adjustment method for protecting against excessive feeding, which specifically comprises the following steps: Step S1: During the operation of the online adjustment and treatment system for abnormal working conditions of the long-distance pipeline slurry concentration system, the feed flow rate and concentration are detected: after the upstream feed pipeline receives the feed, the feed concentration C0, mass concentration, %, and the slurry volume V0, m are recorded by the concentration meter and flow meter on the feed pipe. 3 / h, and get the incoming dry ore quantity Q0, t / h: Among them, ρ s is the density of the concentrated mineral, t / h; Step S2: the future dry ore quantity Q0 and the maximum processing capacity of the thickener Q max In comparison, when Q0>1.25Q max , it is judged as "high feed amount"; Among them, the maximum processing capacity of the thickener is Q max The value of is determined as follows: the maximum amount of dry ore fed without causing the thickener rake torque to rise to 80% of the limit value at the maximum delivery flow of the underflow pump; Step S3: When the system determines that the feed volume is high, the electric valve (7) of the emergency pipeline is opened, and the slurry is transported to the emergency mixing tank (5) through the slurry distribution box (4). At the same time, the flow control valve (9) is adjusted to ensure that the dry ore volume Q0 entering the slurry collection box (1) is less than Q max , then adjust the frequency of the underflow pump (3) so that the concentration of the concentrated underflow is higher than the normal conveying concentration, and then convey it to the slurry distribution box (4), where this part of the slurry is mixed with the slurry entering the emergency accident stirring tank (5) after diversion in the tank body to be prepared into a slurry that meets the conveying requirements; Step S4, until Q0 < 1.25Q is detected max After that, the electric valve (7) is closed to stop the overcurrent protection of the concentration system.

8. The method for online adjustment and processing of abnormal operating conditions of a long-distance pipeline slurry concentration system according to claim 7 is characterized in that: The method for preparing the slurry that meets the transportation requirements in step S3 is specifically as follows: (1) Detect the upstream incoming material volume Q0 and the actual slurry volume Q1 entering the thickener system, and at the same time detect the incoming slurry concentration C0 (2) Adjust the frequency of the underflow pump and detect the outlet pressure of the underflow pump at the same time to keep the delivery pressure at P out , this pressure is higher than the normal slurry delivery pressure, where P out Calculate according to formula (2)-(5): P out =ρ 底 ×g×H1+P 损 (2) Wherein, H1 is the height difference from the underflow pump outlet to the slurry distribution box, m; P 损 is the loss along the pipeline, MPa; ρ 底 is the density of the underflow slurry, kg / m 3 ; C 底 is the underflow slurry concentration, %; V 底 is the volume of the underflow slurry, m 3 / h; C min The minimum concentration of slurry that meets the transportation conditions, %; ρ 底 is the density of the underflow slurry, kg / m 3 ; g is the acceleration due to gravity, m / s 2 , ρ s is the density of the concentrated mineral, kg / m 3 .

9. A method for online adjustment and processing of abnormal operating conditions of a long-distance pipeline slurry concentration system, characterized in that: It includes an online slurry adjustment method for insufficient feed concentration and an emergency protection method for pipeline blockage, which specifically includes the following steps: Step S1. During the operation of the online adjustment system for abnormal conditions of the long-distance pipeline slurry thickening system, the feed volume Q0 is compared with the rated processing capacity Q 额 Compare, when Qs in <0.7Q 额 , it is judged as "feed amount is too low"; Step S2. Observe the outlet pressure P of the underflow pump out , when the outlet pressure P out When the pressure is less than the lowest preset pressure P0, the frequency of the underflow pump (3) is reduced, and the self-circulation pipeline switch electric valve (11) is opened at the same time, so that the concentrated underflow starts to circulate self-suspension; The minimum preset pressure is calculated by the following formula: P0=ρ min ×g×H1+P 损 (6) Among them, ρ min The slurry density corresponding to the minimum allowable conveying concentration slurry, kg / m 3 , H1 is the height difference from the underflow pump outlet to the slurry distribution box, m; Step S3, after the self-circulation starts, the outlet pressure of the underflow pump (3) will continue to rise, and the rise of the outlet pressure of the underflow pump is continuously observed; Step S4: when the outlet pressure of the underflow pump (3) reaches the maximum preset pressure P1, the normal slurry delivery pipeline switch electric valve (12) is opened, and the frequency of the underflow pump (3) is increased at the same time, until the outlet pressure of the underflow pump (3) begins to gradually decrease. When the outlet pressure of the underflow pump is less than P0, step S1 is repeated; The maximum preset pressure is calculated by formula (7): P1=ρ max ×g×H2+P 损 (7) Among them, ρ max The slurry density corresponding to the maximum allowable conveying concentration slurry, kg / m 3 ; H2 is the height difference from the underflow pump to the feed collection box, m; P 损 is the friction loss along the self-circulating pipeline, MPa.

10. A method for online adjustment and processing of abnormal operating conditions of a long-distance pipeline slurry concentration system, characterized in that: Including pipeline blockage emergency protection method, specifically including the following steps: Step S1, during the operation of the online regulation and treatment system for abnormal working conditions of the long-distance pipeline slurry concentration system, when the outlet pressure of the underflow pump (3) increases to the limit pressure P due to a sudden change in the upstream process or due to improper on-site operation, max At the same time, it is observed that the liquid level in the mixing tank rises slowly or does not rise, which is judged as "pipeline blockage warning"; Ultimate pressure P max Calculate using formula (8): P max =1.25×ρ max ×g×H1+P 损 (8) Step S2: When the "pipeline blockage warning" appears, immediately increase the frequency of the underflow pump (3). If the pressure gradually drops to P during the process, out <P max At the same time, if the liquid level in the stirring tank rises normally, the warning is lifted. If the outlet pressure of the underflow pump (3) continues to rise, the operation is carried out according to step S3. Step S3, the outlet pressure of the underflow pump (3) continues to rise, indicating that the slurry concentration in the pipeline is too high or the mineral powder is seriously blocked at the corner. The lift of the underflow pump (3) alone is no longer able to push the slurry in the pipeline to move. At this time, the flushing water switch electric valve (14) is opened to backwash the underflow pump and the thickener, and the vent pipe is opened to release the slurry. At the same time, the valve (12) is opened to transfer the slurry to the emergency accident mixing tank (5). The slurry transfer time is adjusted according to the on-site processing time; Step S4, after the pipeline is dredged, the slurry is prepared to meet the transportation requirements.

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