Academic literature on the topic 'Weak Black Liquor'
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Journal articles on the topic "Weak Black Liquor"
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SANTOS, RICARDO, and PETER HART. "Commissioning brownstock washing controls for an evaporator limited mill." July 2016 15, no. 7 (August 1, 2016): 459–64. http://dx.doi.org/10.32964/tj15.7.459.
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An automated shower water control system has been implemented to reduce the volume and variability of weak black liquor being sent from the pulp mill to the evaporators. The washing controls attempt to balance the need for consistent and low soda carryover to the bleach plant with consistently high weak black liquor solids being sent to the evaporators. The washer controls were implemented on two bleachable grade hardwood lines (one with oxygen delignification, one without oxygen delignification) and one pine line. Implementation of the control program resulted in an increase in black liquor solids of 0.6 percentage points for the hardwood lines. Significant foam reduction was realized on the pine line since the pine black liquor solids were able to be consistently maintained just below the soap separation point. Low black liquor solids excursions to the evaporators were eliminated. Bleach plant carryover was stabilized and no negative impact on chemical consumption was noticed when controlling weak black liquor solids to recovery.
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SINQUEFIELD, SCOTT. "A model black liquor formulation for use in development and evaluation of membranes for concentrating weak black liquor." February 2022 21, no. 2 (March 1, 2022): 109–12. http://dx.doi.org/10.32964/tj21.2.109.
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As part of a larger program to develop robust membranes for concentrating weak black liquor prior to the evaporation step, several commercially available membranes were tested for suitability in this application. Given the variation in kraft black liquor for various wood species, the mill-to-mill variations, and the challenges of obtaining fresh samples, the need became apparent for a synthetic reference black liquor that would allow any membrane developer to test a new prototype membrane and compare the results with others. We present a formulation for a model black liquor (MBL) similar to real kraft black liquor in the composition of the major species that can be formulated from readily available reagents. The MBL was tested with two commercial membranes and resulted in similar levels of lignin retention as the real black liquor. It also showed similar viscosity behavior to real black liquor as a function of solids content.
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Nikolskaya, Ekaterina, Petri Janhunen, Mikko Haapalainen, and Yrjö Hiltunen. "Solids Content of Black Liquor Measured by Online Time-Domain NMR." Applied Sciences 9, no. 10 (May 27, 2019): 2169. http://dx.doi.org/10.3390/app9102169.
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Black liquor, a valuable by-product of the pulp production process, is used for the recovery of chemicals and serves as an energy source for the pulp mill. Before entering the recovery unit, black liquor runs through several stages of evaporation, wherein the solids content (SC) can be used to control the evaporation effectiveness. In the current study, the time-domain nuclear magnetic resonance (TD-NMR) technique was applied to determine the SC of black liquor. The TD-NMR system was modified for flowing samples, so that the black liquor could be pumped through the system, followed by the measurement of the spin-spin relaxation rate, R2. A temperature correction was also applied to reduce deviations in the R2 caused by the sample temperature. The SC was calculated based on a linear model between the R2 and the SC values determined gravimetrically, where good agreement was shown. The online TD-NMR system was tested at a pulp mill for the SC estimation of weak black liquor over seven days without any fouling, which demonstrated the feasibility of the method in a harsh industrial environment. Therefore, the potential of the TD-NMR technology as a technique for controlling the black liquor evaporation process was demonstrated.
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Chu, Zhao Hua, Xu Geng, and Cheng Lin Zheng. "Influence of Influent Concentration on Papermaking Black Liquor Treatment with Wet Air Oxidation Method." Applied Mechanics and Materials 260-261 (December 2012): 1263–69. http://dx.doi.org/10.4028/www.scientific.net/amm.260-261.1263.
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Black liquor was processed with wet air oxidation technology in these experiments. Influence of its influent concentration was researched. COD, absorbance, turbidity and pH of the water samples were measured and analyzed. The results showed that: the treatment effect of each index in black liquor treatment with wet air oxidation method gradually weakened with the increase of influent concentration from the overall point of view; when papermaking black liquor was processed by wet oxidation, the water samples was weak alkaline basically, with pH in between 7.83 to 8.70. COD removal, decolorization removal and turbidity removal basically improved with the extension of time, the COD removal and decolorization removal can reach 50 % or more basically. When influent concentration was greater than 5500 mg/L, turbidity removal was less than 40 %. So the influent concentration of the black liquor in wet oxidation treatment should not be too large, the influent concentration of 2500 mg/L to 4000 mg/L is appropriate.
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MEYER, TORTSEN, HEATHER MUNN, and HONGHI TRAN. "Causes of poor dregs settling in a green liquor clarifier." August 2022 21, no. 8 (September 1, 2022): 435–42. http://dx.doi.org/10.32964/tj21.8.435.
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A study was conducted to examine the most likely parameters responsible for poor dregs settling at a kraft mill over a 2.5-year period, using multivariate data analysis (MVDA) and machine learning (ML) techniques. The dregs settling behavior seems to be seasonally influenced, implying that wood quality variation can be a factor. The results from the MVDA/ML analysis show that poor dregs settling is correlated to incomplete combustion and/or low load conditions in the recovery boiler, low sulfidity in the causticizing plant, and high flow in the green liquor–weak wash cycle. Compositions of dregs and black liquor were also examined to identify correlations with impaired dregs settling. The results show that poor dregs settling strongly correlates with high silicon (Si) content in dregs and moderately correlates with high iron (Fe) and high aluminum (Al) contents, and with low bulk density in dregs. For mills that experience dregs settling or green liquor filtering issues, regular compositional analyses of dregs, green liquor, weak wash, and black liquor are recommended in order to monitor the dynamics of silicon and other constituents in the recovery cycle.
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Hubbe, Martin A., Raimo Alén, Michael Paleologou, Miyuru Kannangara, and Jonas Kihlman. "Lignin recovery from spent alkaline pulping liquors using acidification, membrane separation, and related processing steps: A Review." BioResources 14, no. 1 (2019): 2300–2351. http://dx.doi.org/10.15376/biores.14.1.hubbe.
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The separation of lignin from the black liquor generated during alkaline pulping is reviewed in this article with an emphasis on chemistry. Based on published accounts, the precipitation of lignin from spent pulping liquor by addition of acids can be understood based on dissociation equilibria of weak acid groups, which affects the solubility behavior of lignin-related chemical species. Solubility issues also govern lignin separation technologies based on ultrafiltration membranes; reduction in membrane permeability is often affected by conditions leading to decreased solubility of lignin decomposition products and the presence of colloidal matter. Advances in understanding of such phenomena have potential to enable higher-value uses of black liquor components, including biorefinery options, alternative ways to recover the chemicals used to cook pulp, and debottlenecking of kraft recovery processes.
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Huet, Marion, Anne Roubaud, and Dominique Lachenal. "Conversion of sulfur-free black liquor into fuel gas by supercritical water gasification." Holzforschung 69, no. 6 (August 1, 2015): 751–60. http://dx.doi.org/10.1515/hf-2014-0254.
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Abstract Supercritical water gasification of weak sulfur-free black liquor (BL) was performed in a batch autoclave at temperatures between 430°C and 470°C, pressure between 24 and 27 MPa and residence time between 2 and 63 min. Results show that the gas produced was a mixture of mainly hydrogen, methane, and carbon dioxide. Maximum conversion was achieved at 470°C and 60 min. Energy recovery (ER, ratio between the energy in the gas and in the initial BL) was 46%. Thirty-four percent of the carbon and 53% of the hydrogen initially present in BL were converted into gases. Nearly 15% of initial organic carbon remains in the liquid phase and consists mainly of phenolic compounds, which are stable under those conditions. A higher temperature is needed to convert all the organic carbon. Thermodynamic equilibrium should be reached at 700°C leading to a complete conversion and a better efficiency. Sodium recovery is close to typical kraft recovery value and compatible with causticizing.
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Verma, Om Prakash, Toufiq Hazi Mohammed, Shubham Mangal, and Gaurav Manik. "Modeling, simulation and control of the dynamics of a Heptads’ effect evaporator system used in the Kraft recovery processes." Transactions of the Institute of Measurement and Control 40, no. 7 (April 27, 2017): 2278–90. http://dx.doi.org/10.1177/0142331217700239.
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This research article attempts to investigate the dynamic behavior of the heptads’ effect evaporator (HEE) used to concentrate the weak black liquor during the Kraft recovery process in a paper industry. In order to fully characterize the HEE unit, a complete understanding of its performance for steady state and transient conditions is required. For this purpose, a set of first order nonlinear differential equations have been developed for the backward feed flow configuration (BFFC) for an unsteady state. Further, the developed non-linear model is linearized and linear state space equations obtained. The dynamic response of the system in terms of vapor temperature and liquor concentration changes for different changes in input liquor flow rate has been investigated. The rise, delay and settling times for the temperature deviation from steady state have been found to be significantly less as compared with that for the concentration deviation. The results also indicate that each effect of HEE acts as an individual first order system. The placement of such first order systems in series makes both the liquor concentration and vapor temperatures response more sluggish progressively with each subsequent effect. Finally, a Cascade-PID control strategy has been implemented and shown to exhibit differentiated and improved dynamic performance of the HEE system versus open-loop dynamic response.
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Ortega-Clemente, Alfredo, G. Marín-Mezo, M. T. Ponce-Noyola, M. C. Montes-Horcasitas, S. Caffarel-Méndez, Josefina Barrera-Cortés, and Héctor M. Poggi-Varaldo. "Comparison of two continuous fungal bioreactors for posttreatment of anaerobically pretreated weak black liquor from kraft pulp mills." Biotechnology and Bioengineering 96, no. 4 (2007): 640–50. http://dx.doi.org/10.1002/bit.21134.
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RIVERA, DIEGO F., MAX KLEIMAN-LYNCH, BRENT D. KELLER, and STEPHEN F. FRAYNE. "Addressing production bottlenecks and brownstock washer optimization via a membrane concentration system." July 2021 20, no. 7 (August 1, 2021): 467–78. http://dx.doi.org/10.32964/tj20.7.467.
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Advancements in membrane systems indicate that they will soon be robust enough to concentrate weak black liquor. To date, the economic impact of membrane systems on brownstock washing in kraft mills has not been studied and is necessary to understand the viability of these emerging systems and their best utilization. This study investigated the savings that a membrane system can generate related to brownstock washing. We found that evaporation costs are the primary barrier for mills seeking to increase wash water usage. Without these additional evaporation costs, we showed that our hypothetical 1000 tons/day bleached and brown pulp mills can achieve annual savings of over $1.0 MM when operating at higher dilution factors and fixed pulp production rate. We then investigated the impact of increasing pulp production on mills limited by their equipment. In washer-limited mill examples, we calculated that membrane systems can reduce the annual operating cost for a 7% production increase by 91%. Similarly, in evaporator-limited mill examples, membrane systems can reduce the annual operating cost for a 7% production increase by 86%. These results indicated that membrane systems make a production increase significantly more feasible for these equipment-limited mills.
Dissertations / Theses on the topic "Weak Black Liquor"
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Sen, Gupta Supriya Kumar. "Oxidation of sodium thiosulfate in weak kraft black liquor." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66124.
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Halder, Dibyadeep. "Toxicity of opal Australian paper weak black liquors towards actinobacillus succinogenes 130Z." Thesis, Federation University Australia, 2022. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/184110.
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The objective of this study was to gain a better understanding of Opal Australian Paper’s (AP’s) waste streams as a potential substrate for biomanufacturing. Three low-value process streams were included in this study: Continuous Kraft Mill (CKM) weak black liquor (WBL), Neutral Sulphite Semi-Chemical (NSSC) WBL and WBL extracted from NSSC clean-pulp (CP). The primary focus of the study was to determine the chemical composition and extent of toxicity of these WBLs towards Actinobacillus succinogenes 130Z. This genetically engineered bacterium can produce a valuable platform chemical, succinic acid, using various carbohydrate sources. This project sought to increase knowledge of AP’s WBL and its suitability as a biomanufacturing substrate. Literature has been reviewed on various pre-treatment pathways for this waste stream, A. succinogenes 130Z and its effectiveness on producing succinic acid, and the analytical techniques that have been used to answer the project objectives. The effectiveness of pre-treating the NSSC and CP WBLs was measured using the following characteristics: (a) the colour content (specific absorbance) using UV-Vis spectroscopy, (b) indicative yields of several organic constituents through pyrolysis-gas chromatography-mass spectroscopy, (c) the atomic H/C and S/C ratios using an elemental analysis and (d) toxicity of the samples using a combination of semi-quantitative (plating trials) and quantitative (determination of minimum bactericidal concentration) techniques. The impact of an additional pre-treatment step of granular activated carbon for NSSC WBL was also researched here. InfraRed spectroscopy and toxicity analysis helped to conclude that CKM WBL is extremely toxic to Actinobacillus succinogenes 130Z and contained negligible amounts of residual sugar units. Characterising the NSSC and CP WBLs at the molecular level revealed the untreated WBLs are rich in lignin-derived methoxyphenols (up to 160 mg/kg) and contained low concentrations of elemental sulphur (up to approx. 1 mg/kg). Infra-red spectroscopy and gas chromatography indicated that the fermentable sugars in the WBLs were very low (< 1.2 mg/kg) even after pre-treatment. Both methoxyphenols and sulphur are known to be toxic to many bacteria and A. succinogenes 130Z could not tolerate more than 0.45 mg/ml (db, dry basis) and 0.78 mg/ml (db) of NSSC and CP WBLs respectively. Employing Amberlite® XAD7HP resins to pre-treat the NSSC and CP WBLs reduced their toxicity 2- to 5-fold, enabling the bacterium to survive in about 2.5 mg/ml (db) and 1 mg/ml (db) of NSSC and CP WBLs respectively. One possible reason for this is the significant reduction in lignin content afforded by this pre-treatment technique. These results conclude that AP’s WBLs are toxic and need to undergo pre-treatment prior to utilisation as a substrate for succinic acid production via fermentation.Master by Research
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Halder, Dibyadeep. "Toxicity of opal Australian paper weak black liquors towards actinobacillus succinogenes 130Z." Thesis, Federation University Australia, 2022. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/183622.
Full textAbstract:
The objective of this study was to gain a better understanding of Opal Australian Paper’s (AP’s) waste streams as a potential substrate for biomanufacturing. Three low-value process streams were included in this study: Continuous Kraft Mill (CKM) weak black liquor (WBL), Neutral Sulphite Semi-Chemical (NSSC) WBL and WBL extracted from NSSC clean-pulp (CP). The primary focus of the study was to determine the chemical composition and extent of toxicity of these WBLs towards Actinobacillus succinogenes 130Z. This genetically engineered bacterium can produce a valuable platform chemical, succinic acid, using various carbohydrate sources. This project sought to increase knowledge of AP’s WBL and its suitability as a biomanufacturing substrate. Literature has been reviewed on various pre-treatment pathways for this waste stream, A. succinogenes 130Z and its effectiveness on producing succinic acid, and the analytical techniques that have been used to answer the project objectives. The effectiveness of pre-treating the NSSC and CP WBLs was measured using the following characteristics: (a) the colour content (specific absorbance) using UV-Vis spectroscopy, (b) indicative yields of several organic constituents through pyrolysis-gas chromatography-mass spectroscopy, (c) the atomic H/C and S/C ratios using an elemental analysis and (d) toxicity of the samples using a combination of semi-quantitative (plating trials) and quantitative (determination of minimum bactericidal concentration) techniques. The impact of an additional pre-treatment step of granular activated carbon for NSSC WBL was also researched here. InfraRed spectroscopy and toxicity analysis helped to conclude that CKM WBL is extremely toxic to Actinobacillus succinogenes 130Z and contained negligible amounts of residual sugar units. Characterising the NSSC and CP WBLs at the molecular level revealed the untreated WBLs are rich in lignin-derived methoxyphenols (up to 160 mg/kg) and contained low concentrations of elemental sulphur (up to approx. 1 mg/kg). Infra-red spectroscopy and gas chromatography indicated that the fermentable sugars in the WBLs were very low (< 1.2 mg/kg) even after pre-treatment. Both methoxyphenols and sulphur are known to be toxic to many bacteria and A. succinogenes 130Z could not tolerate more than 0.45 mg/ml (db, dry basis) and 0.78 mg/ml (db) of NSSC and CP WBLs respectively. Employing Amberlite® XAD7HP resins to pre-treat the NSSC and CP WBLs reduced their toxicity 2- to 5-fold, enabling the bacterium to survive in about 2.5 mg/ml (db) and 1 mg/ml (db) of NSSC and CP WBLs respectively. One possible reason for this is the significant reduction in lignin content afforded by this pre-treatment technique. These results conclude that AP’s WBLs are toxic and need to undergo pre-treatment prior to utilisation as a substrate for succinic acid production via fermentation.Masters by Research
Book chapters on the topic "Weak Black Liquor"
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Schrad, Mark Lawrence. "“All Great Reforms Go Together”—Temperance and Abolitionism." In Smashing the Liquor Machine, 308–32. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780190841577.003.0011.
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This chapter begins with the starting point of conventional temperance narratives: Lyman Beecher’s Six Sermons on Intemperance (1826), and the American Temperance Society (ATS). Rather than being an admonishment against drinking, his sermons condemned the selling of drink, thus underscoring how the modern temperance movement always tilted against the profit motive of the liquor traffic rather than against booze itself. Understanding prohibitionism as a weapon of the weak, this chapter examines the overlooked role of black temperance at a time when abolitionism and temperance were virtually synonymous. In 1851 Maine rescinded all liquor-selling licenses, making it the first prohibition state: a move applauded by Frederick Douglass and black activists, who equated the bonds of addiction with the bonds of slavery. Even the great emancipator himself—the famously temperate Abraham Lincoln—was instrumental in passing Illinois’s “Maine Law” while a state legislator.
Conference papers on the topic "Weak Black Liquor"
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Wen, Gao, Chongsheng Long, Tang Rui, and Jiping Wang. "The Mechanical Properties and Friction and Wear Behavior of C/C-SIC." In 18th International Conference on Nuclear Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/icone18-29705.
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Carbon fiber reinforced carbon-silicon carbide composites (C/C-SiC) were prepared by chemical volume infiltration (CVI) method and reaction melt infiltration (RMI) technique of silicon liquid to carbon reinforce carbon matrix composites. The friction and wear behaviors of C/C-SiC composites at various loads and sliding speeds were investigated by MRH-3 block-on-ring tribometer at room temperature under water lubricating conditions. Furthermore, the morphologies, phase of the worn surface and the debris were observed, examined and analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDAX) respectively. Experimental results showed that the C/C-SiC composites had a better wear resistence, and the friction coefficient under water lubricated conditions is about 0.02–0.06. The influence of sliding speed on the friction coefficients and the specific wear rate of C/C-SiC is more obvious than that of normal load when the load is less than 200N (inclueded200N). The friction coefficient and the specific wear rate of C/C-SiC decreased as the sliding velocity increased. At the sliding speed higher than 2m/s, the friction coefficient is less than 0.02. The specific wear rates is at a low level about (2×10−7mm3/Nm–5×10−8mm3/Nm).
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Ramidi, Priyatham Sanjeeva Reddy, Nikolaos I. Xiros, Stavros Lalizas, Anastasios Papavasileiou, Vasileios Douvris, Nikolas Theodorou, and Alexandros Lalizas. "System Identification for Control of a Bow Thruster With Brushless Motor and Shaft-Less Propeller." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-88029.
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In this work, a bow thruster is proposed to be used onboard small and medium-size watercraft, like motor yachts, fishing boats, patrol boats, ocean exploration vessels etc. with conventional or unconventional hull designs including displacement hull, planing hull, catamarans, SWATHs, SES, and so on. As oftentimes the case, a magnetic coupling is employed. Specifically, magnetic coupling is used to transfer torque from a brushless motor’s stator to its rotor through a magnetic field rather than a physical mechanical connection. Such magnetic coupling is very convenient for liquid pumps and as, in our case, propeller systems, since a static, physical barrier can be placed between the stationary and rotating part of the system to separate the fluid from the electrically supplied stator operating in air. Therefore, magnetic couplings preclude the use of shaft seals, which eventually wear out and fail from the sliding of two surfaces against each other. In this work, a system identification process of a rim driven bow thruster is implemented employing data series obtained by tests on a prototype scale model. System Identification leads to a black-box model of the system. The model derived can be extrapolated by grey-box modeling techniques for further design improvements. A control system for the proposed thruster is developed and validated through both computer and hardware-in-the-loop simulation, after its implementation onboard a broadly used industrial Programmable Logic Controller (PLC). The mathematical model of the bow thruster mechanism is developed and the performance is analysed by using Matlab/Simulink.
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Zhu, Youyi, and Jian Fan. "Key Innovation Technologies and Practice Effect of Polymer Flooding Field Application." In SPE EuropEC - Europe Energy Conference featured at the 83rd EAGE Annual Conference & Exhibition. SPE, 2022. http://dx.doi.org/10.2118/209696-ms.
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Abstract Chemical flooding technique is the dominating EOR technique in China. Polymer flooding has entered into industrialized applications and has been applied on a large scale in Daqing sandstone reservoir. Now polymer flooding is expanding to other reservoirs such as conglomerate reservoir, complex fault block reservoir and high temperature and high salinity reservoir. The good EOR effect achieved by polymer flooding is closely related to the key innovation technologies. Recent progress of field tests and application of polymer flooding enhanced recovery (EOR) in China was summarized in this paper. Key technical innovations and field application effects was introduced. The challenges faced and the development direction of polymer flooding technology was discussed. Polymer flooding has been applied in Daqing Oilfield from medium-high permeability reservoirs (type I reservoirs) to medium-low permeability reservoirs (type II reservoirs) with poor petrophysical properties. In addition, polymer flooding solution was prepared by dilution of produced water instead of fresh water. 13% incremental oil recovery in average has been obtained. Polymer flooding has expand apply to conglomerate reservoir in Xinjiang Oilfield, complex fault block reservoir in Dagang Oilfield and high temperature and high salinity reservoirs in Shengli Oilfield, the application results was also successful by solving bottleneck technical problems. A series of technologies have been developed for industrialization application of polymer flooding during tests and application. The key innovations are: polymer product evaluation and molecular weight optimization techniques; development of numerical simulation software and optimization of field test scheme; high efficient injection equipment and process; profile modification during polymer flooding; separated layer injection technique; separated molecular weight and pressure injection technology; anti-eccentric wear lifting technology; fracturing and injection technology; dynamic tracking and adjustment technology; produced liquid treatment technology. These innovative techniques ensure good results of polymer flooding in field applications. The key points and practical application of these technologies are illustrated with examples. Polymer flooding is the leading EOR technology for medium and high permeability reservoirs. Polymer flooding has been applied on a large scale and is being extended to more complex reservoirs. Facing new technical challenges, it is necessary to continuously strengthen the research and development of new functional polymers, research of reservoir adaptability and continuously technological innovation of supporting technology for different types of reservoir application.
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Al Anboori, Abdullah, John Northall, Jasem Al Araimi, Said Al Habsi, Ahmed Al Lawati, Sawsan Al Saadi, John Morrison, et al. "Wireline DAS Conveyed Walkaway VSP Trial in the Khazzan Field, Oman - Planning, Operation and Results." In ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211633-ms.
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Abstract The giant Khazzan gas field, onshore Oman covers an area of 2800 km2 and has been on production since 2017. Structural depth is a key uncertainty particularly in the flanks of the field that have fewer wells and low structural relief. With a shallowing GWC in these areas, the water risk increases and consequently, the recoverable gas and associated liquid content have become key development considerations. A well with a vertical seismic profile (VSP) was planned to improve the velocity control, narrow down the structural uncertainty and subsequently de-risk the resources and optimize the development plan in one of the areas where development is sensitive to the depth of the structure. Geomorphologically, this area is in a part of the field where there is a salina (weak evaporites) at surface. The VSP process was split into three phases: planning, operations, and analysis/results. The planning phase focused on the survey design to achieve the VSP objectives by means of: a) reviewing existing VSPs, pre-survey modelling and working closely with technology providers, b) salina engineering feasibility followed by vibrator test on the salina and c) pre-job preparation via conducting ‘shoot the survey on paper’ and ‘risk assessment’ to produce a main plan with back up options that included key decision points. The planning phase concluded with the following recommendations: a) VSP collection using fiber optic hybrid logging cable and Distributed Acoustic Sensing (DAS) technology, to efficiently collect velocity information (although risks to this ‘first of a kind’ operation in the area were mitigated by mobilizing a conventional VSP tool); b) acquire Zero offset (ZO) and walkaway (WA) VSP with 4 km maximum offset to measure anisotropy and velocity away from the well; c) acquire WAVSP along two perpendicular lines to estimate azimuthal anisotropy related to current stress regime; d) use an existing road for the primary WAVSP line and build an additional 4 km road for the second line to mitigate soft conditions in the salina. The salina poses risks to operating vibrators while driving and sweeping and these risks needed to be managed. During the acquisition phase, operational expertise on-site with co-location of the company decision makers would provide around-the-clock support to improve efficiencies and respond rapidly to any operational challenges. One contractor was chosen to provide all VSP services to reduce job complexity and minimize interfaces. VSPs acquired using fiber optic technology are becoming more common but this trial is the first in block 61 and possibly in the area, to use a hybrid optical-electric logging cable to record both zero-offset and walkaways. The ZOVSP DAS data was collected using a formation tester tool in the tool string. This showed inferior data quality due to difficulties in coupling the cable to the borehole wall and casing, which unfortunately limited the success of the trial. Only limited sections of the cable were coupled and could be used for first break time picking. This triggered the backup option, a conventional geophone array deployed with the hybrid cable, to successfully record the ZOVSP and two WAVSP. DAS data was recorded simultaneously, to try using the intervals with good coupling later during data processing.