Pump Maintenance Costs Research Articles

Research on Gravity Energy Saving Reconstruction Technology of Circulating Cooling Water in Mechanical Ventilation Cooling Tower of a Steel Plant

There is a height drop in the rain area of the circulating cooling water in mechanical ventilation circulating cooling towers, resulting in the ineffective use of gravitational potential energy. High-level water collection is an effective way to reduce the energy consumption of the cooling tower. Based on this, aiming to solve the gravity energy waste problem of circulating water in the cooling tower of a steel plant, this paper innovatively puts forward the high-level water tank to utilize the energy-saving transformation technology of turbine power generation and pump power saving. Additionally, this paper explores the energy-saving effects of the two methods under different height drops. The results show that the maximum utilizable rain area height of the cooling tower is 5 m, while the annual electric energy output of turbine technology can reach 4.704 million kW·h. The high water collection technology can reduce pump power consumption and save up to 7.35 million kW·h per year of electric energy, maintaining a more significant energy-saving ability compared with the turbine power generation technology. In terms of performance, the design of a high-level water tank is to help eliminate rain areas and improve the heat exchange efficiency of water and gas, so that the water temperature of the outgoing tower is 0.13 °C lower than that of the conventional cooling tower. Meanwhile, the ventilation resistance in the rain area is weakened, the resistance coefficient can be reduced by about 40–50%, and the noise can be reduced by about 10 dB (A) under the action of the water collection device. According to the economic evaluation, the total cost of turbine power generation technology is 0.563 million dollars and the total cost of high-level water collection technology is 0.446 million dollars. The cost can be realized within two years, but the high-level water collection technology avoids additional pump maintenance costs and has better economy. This study provides a theoretical basis for the transformation and optimization design of mechanical ventilation cooling towers, and has important reference value.

PREDICTING THE TECHNICAL CONDITION OF AN ELECTRIC SUBMERSIBLE PUMP BASED ON NEURAL NETWORK MODELING

The problem of predicting the state of an Electric Submersible Pump during operation is considered. Downtime and shortages caused by pump failure lead to losses in oil pro-duction and require time to replace equipment. By predicting the condition of the equipment, it is possible to minimize pump maintenance costs and reduce well downtime. Expert systems and pre-dictive analytics methods are used to analyze the state of systems. The scientific work uses methods that are based on artificial neural networks. Purpose of research. Elaboration of the issues of fore-casting the technical condition of the pump through by using machine-learning models. Materials and methods. Equipment failure forecasting is carried out using time series analysis. The data was obtained from telemetric sensors of the monitoring system installed on an electric submersible pump. The initial data were taken at one-minute intervals. Initial data preprocessing was carried out. The data was cleared of values (peaks) that are clearly got out of normal operation and places where the phase voltage was equal to zero were removed. An artificial neural network with the LSTM neuron type is used to predict time series. Time series forecasting was carried out for five days. Evaluating system parameters over long periods allows you to assess the condition of its compo-nents and prevent equipment failure. Results. The possibilities of neural networks trained on the ba-sis of data from telemetric sensors of the monitoring system for predicting the values of vertical vi-bration of the pump are investigated. The use of a neural network model in the form of LSTM, which has shown good results in the analysis of time series, is justified. It was found that neural net-works capture the trend well within the time series, which indicates the possibility of using it together with the expert system. Conclusion. The proposed methods and models are tested on real data, which confirms the possibility of their use in the development of an intelligent information system for managing the technical condition of an Electric Submersible Pump during operation.

Simultaneous and sequential stochastic optimization approaches for pumped storage plant scheduling with random breakdowns

This paper addresses a pumped-storage stations scheduling problem. The study contribution is three-fold. First, a new service-related multi-objective function is proposed. The model aims to minimize the supply-demand disparity function and the pump maintenance cost in terms of the number of pump switches. Second, the proposed mathematical formulation considers individual units scheduling and random breakdowns. Furthermore, this work considers the electricity demand uncertainty in hourly and daily basis. Third, a new sequential two-stage formulation is proposed. The Sample Average Approximation method is applied to handle the grid demand uncertainty, stochastic failures and unplanned maintenance of pumping units. Goal programming is applied at the second-stage to handle the conflicting objective functions and avoid the model infeasibility. A case study data based on the Ingula pumped-storage station in South Africa is used to test the performance of the proposed approach. A comparison between the two-stage sequential approach and a simultaneous approach showed the superior performance of the two-stage sequential approach in terms of modeling complexity and computational time. Furthermore, experimental analysis showed that involving more pumping/generating units could improve the service level by reducing Disparity Index. Moreover, the two-stage sequential approach showed a superior performance even for the larger size instances.

Experimental Investigation of the Impact of Coal Fines Migration on Coal Core Water Flooding

Coalbed Methane (CBM) has become an important gas resource in recent decades. The brittle property of coal matrix and overactive operation make the migration of coal fines inevitable. Blockage by coal fines that plugs flow paths is a non-negligible issue that results in a significant decline in gas production. By setting different experimental conditions with the following factors—coal fines concentration of the mixture displacing fluids, constant flow pump rate, inlet pressure, outlet pressure and confining pressure—six experimental schemes were designed to investigate the two-phase water and coal fines flow in natural core samples. When the differential pressure and flooding flow reach a pseudo-steady status, the equivalent permeability of coal samples can be approximately calculated considering coal fines migration. Furthermore, the influences of coal fines migration on the cleat opening and permeability variation are analyzed in the porous coal medium. The study will benefit CBM development and save pump maintenance costs. In this work, we found that maintaining the differential pressure for a longer period may result in new cleat openings and severe coal rock damage during the single-phase water flooding process. While coal fines may plug some natural cleats and pores, especially in the core samples with micro-cleats during the two-phase flooding stage, coal fines migration significantly reduces the equivalent permeability and dewatering ability of the coal rock in the earlier flooding. While enlarging the differential pressure in two-phase water and fines flooding, breakthrough of coal fines from the samples contributes to widened cleats. While coal fines are difficult to flood into the core pores for low-permeability core samples, coal fines gather in the inlet, and it is also difficult to reach the pseudo-steady status even under higher differential pressure. The damage to permeability mainly occurs in the early stage of coal fines migration, and an abrupt increase in the flow velocity can damage reservoirs and induce substantial coal fines generation. Thus, maintaining a stable effective strength and a controlled depressurization rate during drainage can effectively constrain coal fines output and decrease permeability damage within coal reservoirs.

PEMITRA BAGI WILAYAH DESA PUCUNG, KECAMATAN EROMOKO KABUPATEN WONOGIRI

Once the problem of clean water shortage is resolved, new problems arise related to the cost of treating water pumps and water distribution channels through uneven public hydrants. Through the Focus Group Discussion (FGD) activity conducted by UMS Community Service Team which was attended by all heads of Dusun and management of Air Tirta Gua Suruh, it has been formulated the need for productive business in groups related to water utilization which can be used as a joint result for contribution of water pump maintenance cost Cave Suruh. The need for daily vegetable ingredients will be fulfilled independently and group through vegetable crops of pollybag media. The result of the sale of vegetable business of PKK Group and Karangtaruna has added input to the water management cost of Suruh Cave. This PEMITRA UMS Programs in assisting the community to make media pollybag as well as vegetable seed business capital managed by PKK Group in Kangkung and Karangtaruna group in Wijil have been understood.

On the scheduling of real world multiproduct pipelines with simultaneous delivery

Common carrier pipelines are the best suited mode for transporting large volumes of petroleum products from production areas to long-distance terminals. In such pipelines, batches of refined petroleum products are pumped back-to-back, without any physical barrier separating them. The problem addressed in this paper deals with the scheduling of a real world multi-product, single source pipeline system that must supply the products to several offtake terminals. Most contributions on the scheduling of single-source multiproduct pipeline operations deal with the sequence deliveries in distribution terminals i.e., at any time only one terminal is connected to the pipeline. Practically, pipeline operators usually carry out simultaneous deliveries to multiple terminals to cut down the number of pipeline stoppages and pump switchings so as to reduce the energy consumed for resuming flow in idle pipeline segments, and the pump maintenance costs. This paper introduces a novel continuous mathematical approach, mixed integer linear programming to solve the short-term operational planning by allowing the execution of simultaneous deliveries to multiple receiving terminals during a pumping operation. Contrarily to previous continuous approaches that perform the pipeline input/output operations in two hierarchical stages, the new formulation aims to find both of them in a single step. The objective of this work is to find the optimal sequence of input and output operations that satisfy terminal requirements at minimum total costs. As compared to previous works, significantly improvement in solution quality has been achieved. Especially, the proposed formulation leads to better utilization of the pipeline capacity, and consequently, a substantial reduction in the amount of required time for satisfying all of the specified product deliveries, i.e., the pipeline running time. The main results are presented.

Multiobjective Pump Scheduling Optimization Using Harmony Search Algorithm (HSA) and Polyphonic HSA

Harmony Search Algorithm (HSA) is a metaheuristic method that has attracted the scientific interest since its first presentation in 2001. It is a music inspired method, imitating the music creation process in order to find optimal solutions in complicated problems. HSA’s successful application on single – objective optimization problems has resulted to an increasing interest in the implementation of HSA towards multiobjective optimization. The authors have adjusted HSA in order to deal successfully with multi-criteria water management problems. This adjustment has resulted to the creation of Multiobjective – HSA (MO-HSA). In addition, they have designed the multiobjective variant Polyphonic-HSA (Poly-HSA), which is inspired by the independent development of different voices in music and borrows elements from Swarm Intelligence and the single-objective variant Global-Best HSA. In the first part of this paper, both methods are presented in detail. Moreover, the performance of the proposed Algorithms is evaluated using standard multiobjective test – functions. ZDT and DTLZ multiobjective tests have been chosen and indicators such as Hypervolume, C – metric and diversity metric – Δ have been used to measure the convergence to the optimal front and the diversity of the solutions obtained by the proposed methods. In the second part, MO-HSA and Poly-HSA have been introduced towards the optimization of a pump scheduling problem. The objectives considered are water supply, pumping cost, electric power peak demand and pump maintenance cost. Both methods converged to non-dominated fronts and provided excellent results which are presented in 3d figures, indicating that these methods can be effectively used in multiobjective water management problems.

Detailed Scheduling of Operations in Single-Source Refined Products Pipelines

The short-term scheduling of refined products pipelines is a very complex problem with many operational constraints to be considered. Available nondiscrete planning approaches just provide the input schedule and the set of aggregate product deliveries to be performed from in-transit lots to depots at every batch injection. To determine the sequence of individual cuts on each batch to be accomplished by the pipeline operator, it is still necessary to refine such an aggregate plan. To do so, new computational tools for efficiently generating the detailed schedule of single-source pipelines with multiple distribution terminals are presented. Two types of methodologies are proposed. On one hand, it is developed a continuous-time mixed-integer linear programming (MILP) formulation that seeks to minimize both the total flow restart volume and the number of single-delivery pumping runs over the planning horizon. In this way, substantial savings in energy consumption and pump maintenance costs are achieved. Effective solution strategies for the MILP model are also designed to deal with large pipeline scheduling problems. On the other hand, three different heuristic rules for selecting the receiving terminal are introduced. By applying those rules in combination with a discrete-event simulation model, not only alternative detailed schedules can be generated in a very short CPU time but also some of them are near-optimal solutions. Three instances of a case study aimed at finding the detailed schedule of a real-world single-source pipeline system are solved through the proposed optimization and discrete-event simulation methods. Results are analyzed to assess the quality of the generated solutions and the required computational costs.

Optimizing operational efficiency in submersible pumps

In this article, Rob Montenegro, president of Pumpex Inc in the USA, and Nils Hökby, R&D director of Pumpex in Sweden, describe how their company, a specialist manufacturer of submersible pumps, has reduced pump maintenance costs and improved the effectiveness of its pumps by successfully combining high-efficiency hydraulic ends and motors with highly engineered user-friendly features.

Technical Potential of Methods for Methane Extraction From Geopressured-Geothermal Fluids at High Temperature and Pressure

Summary Retaining pressure for direct-drive injection disposal of geopressured fluids is particularly cost-effective when combined with recovery of residual dissolved methane. We examine the technical feasibility of several chemical and mechanical techniques for extracting methane, and discuss specific chemical extractants, pros and cons of processes, and problems of implementation. Introduction Recent technical and economic assessments of methane (CH4) production from geopressured-geothermal reservoirs in the Texas and Louisiana gulf coast area have been made by Swanson and Osoba and Doscher et al. They conclude that to obtain a reasonable return on capital for CH4 recovery from reservoirs with properties shown in Table 1, the CH4 selling price must be in the range of $7.50 to $9.24/Mcf. Samuels also concludes that "unless the methane content and market value are sufficient to offset the cost of the production and reinjection wells, there is currently little incentive to develop this resource". It is clear that at the present value of methane (about $3.50/Mcf), commercialization of the geopressured-geothermal resource will not be expected soon. Well capital costs comprise the major share of expenses, but the operating and maintenance (O and M) costs for injection are also significant. Doscher et al. approximate the O and M costs for injection with the following formula. (1) where $/Mcf is the selling price of CH4 and p is the required injection pressure in 103 psi. Pump power costs are proportional to injection pressure and the value of CH4. The 2 cent constant accounts for pump maintenance costs. At 40 scf of CH4/bbl brine, the value of CH4/bbl brine is 0.04 ($/Mcf). Assuming that pressure required for injection into shallow aquifers (6,000 ft deep) is 1,000 psi, the ratio of injection O and M costs to the value of CH4 is given by (2) From Eq. 2, the injection O and M costs relative to the value of CH4 are between 17.5% for $10/Mcf gas and 26.8% for $3.50/Mcf gas, clearly a significant percentage. The O and M costs are predominantly pump power and maintenance costs, which rise steeply with required injection pressure and become prohibitively high for geopressured waters with low CH4 content. It is clear that measures that could reduce injection costs would contribute significantly to the economic viability of geopressured resource development. One potential option in the production of geopressured aquifers is to maintain sufficient pressure at the wellhead to reduce the injection-pump workload. For shallow injection horizons, direct injection without pumping may be feasible. If it becomes necessary to inject into the production reservoir for pressure maintenance and subsidence control, injection-pumping O and M costs could easily exceed the value of recoverable CH4. Again, by efficient use of excess wellhead pressures, the power requirements for injection pumping could be reduced substantially. However, the potential savings would be offset by the loss of CH4 still dissolved at the elevated pressures, as shown by the solubility curves in Fig. 1. Therefore, there is an incentive for extracting CH4 at high pressures and also at production fluid temperatures to permit recovery of the thermal-energy component from the CH4-depleted brine. There are several potential methods for extracting dissolved CH4 at produced-brine temperatures of 302 deg. F and at anticipated pressures of 1,000 to 1,500 psi for injection into 6,000-ft-deep aquifers. The chemical techniques include gas stripping, which is technically viable but may not be economical, and solvent extraction. JPT P. 504^