Life Cycle Analysis of the Raseta Pump Using OpenLCA

Developed and crafted in Madagascar, the Raseta pump is a novel hydraulic ram (hydram) pump using a springs system. It operates differently from other pumps by the exclusive use of water energy due to the water hammer phenomenon induced by the sudden stop of the water flow. The present study initiates the investigation of the environmental impacts of this new type of hydram pump through a life cycle analysis using OpenLCA 1.8. It was found that, when operating in a small-scale water pumping system, the choice of the pump supply pipe material has small differences of environmental impacts, whether the material is made of steel or polyvinyl chloride (PVC). Moreover, compared to a solar pump for the same pumping flow rate, the use of the Raseta pump is more environmentally friendly and less harmful to human health. However, the actual advantageous utilization of such a system needs further studies such as social and techno-economic analysis.

Vulnerability of water distribution networks with real-life pipe failure statistics

Reasons for occasional, random pipe bursts in water distribution networks (WDNs) might come from numerous factors (e.g. pH value of the soil, the pipeline material). Still, the isolation of the damaged section is inevitable. While the corresponding area is segregated by closing the isolation valves, there is a shortfall in drinking water service. This paper analyses the vulnerability of segments of WDNs from the viewpoint of the consumers that is the product of the failure rate and the relative demand loss. Real pipe failure database, pipe material and pipe age data are used to increase the accuracy of the failure rate estimation for 27 real-life WDNs from Hungary. The vulnerability analysis revealed the highly exposed nature of the local vulnerabilities; the distribution of local vulnerability values follows a power-law distribution. This phenomenon is also found by investigating the artificial WDNs from the literature using N rule in terms of isolation valve layout, namely the ky networks, with similar results.

The Impact of Pipe Material on the Diversity of Microbial Communities in Drinking Water Distribution Systems

As many cities around the world face the prospect of replacing aging drinking water distribution systems (DWDS), water utilities must make careful decisions on new pipe material (e.g., cement-lined or PVC) for these systems. These decisions are informed by cost, physical integrity, and impact on microbiological and physicochemical water quality. Indeed, pipe material can impact the development of biofilm in DWDS that can harbor pathogens and impact drinking water quality. Annular reactors (ARs) with cast iron and cement coupons fed with chloraminated water from a municipal DWDS were used to investigate the impact of pipe material on biofilm development and composition over 16 months. The ARs were plumbed as closely as possible to the water main in the basement of an academic building to simulate distribution system conditions. Biofilm communities on coupons were characterized using 16S rRNA sequencing. In the cast iron reactors, β-proteobacteria, Actinobacteria, and α-proteobacteria were similarly relatively abundant (24.1, 22.5, and 22.4%, respectively) while in the cement reactors, α-proteobacteria and Actinobacteria were more relatively abundant (36.3 and 35.2%, respectively) compared to β-proteobacteria (12.8%). Mean alpha diversity (estimated with Shannon H and Faith’s Phylogenetic Difference indices) was greater in cast iron reactors (Shannon: 5.00 ± 0.41; Faith’s PD: 15.40 ± 2.88) than in cement reactors (Shannon: 4.16 ± 0.78; Faith’s PD: 13.00 ± 2.01). PCoA of Bray-Curtis dissimilarities indicated that communities in cast iron ARs, cement ARs, bulk distribution system water, and distribution system pipe biofilm were distinct. The mean relative abundance of Mycobacterium spp. was greater in the cement reactors (34.8 ± 18.6%) than in the cast iron reactors (21.7 ± 11.9%). In contrast, the mean relative abundance of Legionella spp. trended higher in biofilm from cast iron reactors (0.5 ± 0.7%) than biofilm in cement reactors (0.01 ± 0.01%). These results suggest that pipe material is associated with differences in the diversity, bacterial composition, and opportunistic pathogen prevalence in biofilm of DWDS.

An Impact-Echo Experimental Approach for Detecting Concrete Structural Faults

For the current problem of detection of grouting defects in posttensioned prestressed concrete members, the paper takes a single-layer arrangement of prestressed pipes as the object of study. The influence law of the main factors such as pipe material, defect size, defect critical surface location, and prestressing reinforcement location on the results of the impact-echo method for detecting concrete grouting defects was studied. Firstly, the ABAQUS finite element software was used to simulate these factors to obtain the influence law on the detection results, and a modal test was conducted to verify them. The results show that the impact-echo method can effectively test the location of defects and the degree of burial depth, and the pipe material influences the test results, and the impact of corrugated metal pipe is smaller and more accurate than the PVC pipe. In addition, the greater the plate thickness frequency drift rate, the larger the transverse size of the defect, so the plate thickness frequency drift rate and the measured defect depth are combined to quantitatively determine the depth of the defect.

Ultimate Axial Load Prediction Model for X65 Pipeline with Cracked Welding Joint Based on the Failure Assessment Diagram Method

Crack defects in the girth welds of pipelines have become an important factor affecting the safe operation of in-service oil pipelines. Therefore, it is necessary to analyze the factors affecting the safe operation of pipelines and determine the ultimate load during pipeline operation. Based on the failure assessment diagram (FAD) method described in the BS 7910 standard, the key factors affecting the evaluation results of the suitability of X65 pipeline girth welds are analyzed, and the effects of crack size, pipe geometry, and material properties on the evaluation results are investigated. The results indicate that the crack depth is more crucial to the safe operation of the pipeline than the crack length. While the effect of wall thickness is not significant, the misalignment can seriously aggravate the stress concentration. In general, the higher the yield ratio and tensile strength of the pipe material, the more dangerous the condition at the weld. The ultimate axial load that a crack-containing girth weld can withstand under different combinations of the above factors was determined. Furthermore, a data driven model via the optimized support vector regression method for the ultimate axial load of the X65 pipe was developed for engineering application, and the comparison results between the FEM results and the predicted results proved its accuracy and reliability.

Advances in operating capacity and life time of centrifugal cast pipes for high-temperature pyrolysis of NRC “Kurchatov Institute” – CRISM “Prometey”

On the basis of expert examinations of spent pipes metal operated as coil-pipes at pyrolysis furnaces, heat-resistant alloys and technologies for manufacturing standard products from them have been developed. The service characteristics of the developed alloy 45Kh32N43SB and its welded joints at temperatures of 1100 and 1150°C have been investigated. It is shown that the alloy has structural stability and the ability to resist high-temperature creep at operating temperatures up to 1150°C. A method has been developed for assessing the resource of pipe elements, taking into account the peculiarities of its operation, as well as crack-like defects in the pipe material. The reasons for the significant deformation and damage of the crossover piping, leading to the premature failure of the coils, have been found. The most significant operational factor of damage to the heat exchangers at pyrolysis plants has been identified.

Laboratory Experimental Study on Influencing Factors of Drainage Pipe Crystallization in Highway Tunnel in Karst Area

The crystalline blockage of tunnel drainage pipes in a karst area seriously affects the normal operation of drainage system and buries hidden dangers for the normal operation of the tunnel. In order to obtain the influencing factors and laws of tunnel drainage pipe crystallization in a karst area, based on the field investigation of crystallization pipe plugging, the effects of groundwater velocity, drainage pipe diameter, drainage pipe material, and structure on the crystallization law of tunnel drainage pipe in karst area are studied by indoor model test. The results show that: (1) With the increase of drainage pipe diameter (20–32 mm), the crystallinity of drainage pipes first increases and then decreases. (2) With the increase of water velocity in the drainage pipe (22.0–63.5 cm·s−1), the crystallinity of the drainage pipes gradually decreases from 1.20 g to 0.70 g. (3) The crystallinity of existing material drainage pipe is: M3 (poly tetra fluoroethylene) > M2 (pentatricopeptide repeats) > M4 (high density polyethylene) > M1 (polyvinyl chloride); M8 (polyvinyl chloride + coil magnetic field) is used to change the crystallinity of drain pipe wall material. (4) When the groundwater flow rate is 34.5 cm·s−1, M1 (polyvinyl chloride) and M8 (polyvinyl chloride + coil magnetic field) can be selected for the tunnel drainage pipe. The research on the influencing factors of tunnel drainage pipe crystallization plugging fills a gap in the research of tunnel drainage pipe crystallization plugging. The research results can provide a basis for the prevention and treatment technology of tunnel drainage pipe crystallization plugging.

Analysis of Temperature Variations, Types of Insulation and Coating on Corrosion Under Insulation on ASTM A53 Pipes

Corrosion Under Insulation (CUI) can be described as localized corrosion that forms as a result of the penetration of water or moisture through an insulating material. The pipe material used is of the ASTM A53 standard and the fluid used in seawater because almost all industries are located on the coast. This type of coating is carried out on the test pipe using Meiji Epoxy Filler. The test method is carried out by flowing seawater fluid in pipes with water temperature variations of 30°C, 50°C, and 70°C. This pipe varies the type of insulation by using glasswool and Rockwool (ASTM G 189-07). This insulation is conditioned in a wet state by giving 2 ml of seawater drops with a pH value of 4 per 6 hours. The test equipment is divided into 3 series according to temperature variations with 4 test specimens and 2 coating variations respectively. The test time was carried out for 336 hours to obtain the corrosion rate results using the ASTM G31-72 weight loss method. The results showed that the type of Glasswool insulation with specimens coated had the lowest corrosion rate value of 0.00483 mmpy at a temperature of 30°C when compared to the same type of treatment on Rockwool insulation of 0.00724 mmpy or an increase of 2.41 times. This study shows that the type of insulation, temperature variation, and coating greatly affect the rate of corrosion and the type of corrosion that occurs is uniform corrosion.