High Pressure Water Scrubbing Research Articles

A Comprehensive Review on Biomethane Production from Biogas Separation and its Techno-Economic Assessments.

Biogas offers significant benefits as a renewable energy source, contributing to decarbonization, waste management, and economic development. This comprehensive review examines the historical, technological, economic, and global aspects of biomethane production, focusing on the key players such as China, the European Union, and North America, and associated opportunities and challenges as well as future prospects from an Australia perspective. The review begins with an introduction to biogas, detailing its composition, feedstock sources, historical development, and anaerobic digestion (AD) process. Subsequently, it delves into major biomethane production technologies, including physicochemical absorption, high-pressure water scrubbing (HPWS), amine scrubbing (AS), pressure swing adsorption (PSA), membrane permeation/separation (MP), and other technologies including organic solvent scrubbing and cryogenic separation. The study also discusses general guidelines of techno-economic assessments (TEAs) regarding biomethane production, outlining the methodologies, inventory analysis, environmental life cycle assessment (LCA), and estimated production costs. Challenges and opportunities of biogas utilization in Australia are explored, highlighting and referencing global projections, polarization in production approaches, circularity in waste management, and specific considerations for Australia. The review concludes discussing future perspectives for biomethane, emphasizing the importance of technological advancements, policy support, and investment in realizing its full potential for sustainable energy and waste management solutions.

Optimization of Biogas Purification Employing High-Pressure Water Scrubbing

Purification of biogas is the pre-requisite of the commercial application of anaerobic digestion in the renewable energy sector. In this study, Aspen Plus V11.1 was used to determine the optimum process conditions for biogas purification using high-pressure water scrubbing. The non-random two-liquid model (NRTL) coupled with Henry' s law was used as the fluid package in this study. According to henry' s law solubility of CO2 is higher than CH4 and thus water was used as an adsorbent. The ideal parameter values for the scrubber were as follows: water pressure: 8 atm, biogas temperature: 37°C or 55°C, scrubber stages: 15, water to biogas mass flowrate ratio: 50. The composition of the biogas i. e., CH4 and CO2 mole fractions can vary in a wide range without effecting the efficiency of the process.

Innovative high-pressure water scrubber for biogas upgrading at farm-scale using vacuum for water regeneration

Biogas upgrading is becoming essential in the valorization path for biogas. Biomethane from anaerobic digestion is identified to be one of the main resources to decarbonize the energy requirement. However, small-scale (especially farm-scale) applications suffer from a lack of implementation worldwide, mainly limited by the cost of the upgrading process. As one of the most used technologies, High Pressure Water Scrubbing presents a great margin for improvement. The most expansive items in this technology remain the packing column used for absorption and the stripping column used for water regeneration. In this work, the stripping column is replaced by a flash tank submitted to a rough vacuum (up to 0.2 bar in absolute pressure) associated to a static mixer to promote the gas desorption and thus the complete regeneration of the water. The implementation of an anisotropic packing, with properties evolving with the height of the column and adapted to the reduction of the gas flowrate due to absorption, is also investigated in order to reduce the size of the absorption column. A full-scale prototype was developed and implemented on a farm anaerobic digester. The range of application is from 20 to 40 Nm3/h of raw biogas. These field experiments associated to a complete description of the gas fluxes allowed to characterize the device in terms of carbon dioxide absorption efficiency, biomethane purity and methane recovery. Influences of six parameters (absorption pressure, desorption pressure, temperature, water flowrate, biogas flowrate, column height) were elucidated regarding those performances. Results highlight the great improvement of the water regeneration conducted under rough vacuum. From 0.8 to 0.2 bar in absolute pressure, the biomethane purity increased by 10%, the carbon dioxide elimination rate by 14%, and the methane recovery by 19%. With an increase in the packing height using an anisotropic configuration (modification of the packing properties with the column height) suited to the gas flowrate decrease into the column, a biomethane purity over 97% was obtained. The energy consumption associated was measured at 0.8 kWh/Nm3 of raw biogas but can be reduced to 0.3 kWh/Nm3. The overall energy efficiency for biogas upgrading can reach up to 91%. These results could pave the way for gas grid injection and vehicle fuel applications for small-scale anaerobic digestion.

Miniaturization of Biogas Upgrading Via High Pressure Water Scrubbing to Enhance Economic Competitiveness of Distributed Biomethane

Biogas is an important clean and low carbon energy for rural area, which is confronted with the low heat value, pollutant emission during combustion. The pollutant absorbing technology was employed to develop the small scale portable biogas upgrading equipment to remove CO2, H2S and other impurities in this work. The scheme based on the high pressure water scrubbing technology (HPWS) were proposed including adsorption, flashing, stripping and water recovery. Aspen Plus were used to investigate the effect of adsorption pressure, number of plates, and flash pressure on CH4 purification. The mole fraction of CH4 in final stream increased to 95.6% and levelled off around 97% with the increasing of flash pressure and absorber pressure. The water consumption will decrease with the increase of the number of plates. When the number of plates is above 7, the reduction of water consumption will not be obvious. The principle equipment was developed and tested, indicating the high separation efficiency.

A unique biomass based integrated energy system for cleaner production of multiple energy outputs for sustainable communities

Development of integrated energy systems where food wastes are converted into useful forms of energy is critical for establishing sustainable communities. In this study, a unique integrated energy system is developed and comprehensively analyzed to provide clean and sustainable electricity, biomethane, hydrogen, and heating from organic biomass energy and off-peak period excess electricity. An application of the developed system is considered for the Durham Region in Ontario, Canada. The organic food wastes collected under the Durham's green bin program are anaerobically digested to produce biogas. A high-pressure water scrubbing technique is utilized to upgrade the produced biogas to high purity biomethane. Excess electricity available during off-peak energy periods in the region is utilized for hydrogen production via proton exchange membrane water electrolysis. The produced biomethane and hydrogen is blended to synthesize an energy-dense fuel that is considered for power and heat generation via a combined regenerative gas-steam power cycle as well as a cleaner fuel for public transit buses in the region. On an annual basis, the proposed system provides about 1966 tons of biomethane from food wastes and about 298 tons of H2 from excess off-peak electricity in the Durham Region. Furthermore, the current integrated system is capable of producing 10.72 MW of electricity and 7.5 MW of heat for space heating and hot water applications. The overall energetic and exergetic efficiencies of the system are obtained as 67.25% and 45.16%, respectively.

A unique solar and biomass-based system for integrated production of electricity, heat, freshwater, hydrogen and ethanol

Renewable energy sources are expected to replace fossil fuels to hinder global warming. In order to use these sources more effectively, multigenerational integrated systems where they produce multiple useful outputs with the same input(s), are necessary. This study proposes a novel solar and biomass energy-based integrated system to produce electricity, heating, freshwater, and ethanol. Food waste is anaerobically digested to generate biogas which is then upgraded to biomethane by high pressure water scrubbing. Simultaneously, solar energy is absorbed by parabolic trough solar collector farm to generate power in an organic Rankine cycle and desalinate seawater in a multi-effect desalination unit. A part of the produced electricity is used to obtain hydrogen through an alkaline electrolyzer which is then converted to ethanol by the direct carbon dioxide hydrogenation. The system is modeled and analyzed to present the energy and exergy efficiencies of each subsystem, as well as the overall system. The useful outputs are calculated as 1672.8 kW electricity, 3846 kW heating, 2.06 kg/s freshwater, and 0.02813 kg/s ethanol. The overall energy and exergy efficiencies of the proposed system are found as 53.4 % and 41 %, respectively. It is demonstrated that coupling several subsystems in a conceptually correct manner is important to make them thermodynamically more sound, environmentally more friendly and sustainably more appealing.

Current Status of Biological Biogas Upgrading Technologies

To limit global warming, ratio of renewable sources in the energy mix has to be considerably raised in the following years. While application of e.g. wind and solar power usually generates fluctuations in the electric grid, biogas produced in anaerobic processes is an easy-to-store renewable energy source. Raw biogas contains generally ~55–70% methane and ~30–45% carbon-dioxide. Although raw biogas can be utilized directly for combustion or combined heat and power generation (CHP), its methane content can be raised to >95% by upgrading technologies, thus it can be valorized. By upgrading and cleaning, the quality of the upgraded biogas may reach the quality of the natural gas and it may be injected to the gas grid or used as fuel for devices optimized for natural gas. Several physico-chemical upgrading methods are available on the market (e.g. high pressure water scrubbing, pressure swing adsorption, membrane technology, etc.) to remove the carbon-dioxide content of the biogas. Opposite to the physico-chemical methods, where basically the CO2 removal is the main goal, in biological biogas upgrading technologies microorganisms are applied to convert the carbon-dioxide content of the biogas to methane (chemoautotrophic upgrading), or algal biomass (photoautotrophic upgrading). The expectations are high towards biological biogas upgrading technologies in the field of energy storage linked with carbon-dioxide capture. In this paper, latest research results concerning biological biogas upgrading are summarized, viability and competitiveness of this technology is discussed together with the most important future development directions.

Rate-based modeling approach for High Pressure Water Scrubbing with unsteady gas flowrate and multicomponent absorption applied to biogas upgrading

Biogas upgrading aims to increase the methane concentration in biogas by removing carbon dioxide. Upgraded biogas can then be used as a renewable energy resource. Among the technologies used for biogas upgrading, High Pressure Water Scrubbing (HPWS) is one of the most widespread. HPWS is identified as fulfilling all the requirements for farm-scale anaerobic digesters, presenting several levers to reduce operational and installation costs. One possible remedy is to optimize operating parameters to reach targeted gas specifications, without applying excessive treatment or energy consumption. The purpose of this study is to develop an efficient modeling tool that can predict methane purity and its recovery for different operating conditions of gas and liquid. This original model integrates the decrease of gas flow along the packing height and the concomitant absorption of carbon dioxide and methane. The model is based on mass transfer and hydrodynamics to explain and anticipate the performance of HPWS in order to facilitate its implementation on the field. Model results retrieved from a homemade environment on Excel are compared to those of experiments conducted on a farm-scale biogas upgrading plant and show very good agreement. The model demonstrates great adaptability regarding variations of parameters. It can thus be used to anticipate HPWS performance and to optimize running parameters in order to reach targeted purities while making energy consumption more flexible. Water regeneration is identified as the key parameter for compliance with gas injection standards, achieving a purity over 97% and a recovery ratio of 93% at a desorption pressure of 0.2 bar. Results highlight that a rate-based model giving access to molar fraction variation along the column is crucial to adjust operating parameters in order to reach optimal economic and environmental performances. More accurate operating conditions could be the key to lowering costs of production and attaining financial viability for biogas upgrading at farm scale.

Biogas upgrading, economy and utilization: a review

Biogas production is rising in the context of fossil fuel decline and the future circular economy, yet raw biogas requires purification steps before use. Here, we review biogas upgrading using physical, chemical and biological methods such as water scrubbing, physical absorption, pressure swing adsorption, cryogenic separation, membrane separation, chemical scrubbing, chemoautotrophic methods, photosynthetic upgrading and desorption. We also discuss their techno-economic feasibility. We found that physical and chemical upgrading technologies are near-optimal, but still require high energy and resources. Biological methods are less explored despite their promising potential. High-pressure water scrubbing is more economic for small-sized plants, whereas potassium carbonate scrubbing provides the maximum net value for large-sized plants.

Life cycle assessment of food waste to energy and resources: Centralized and decentralized anaerobic digestion with different downstream biogas utilization

Anaerobic digestion (AD) has been identified as an efficient food waste disposal technology by many researchers. However, a holistic environmental investigation of different AD configurations integrated with different downstream biogas utilization has never been reported. This study, taking Singapore as an example, compared the sustainability of business-as-usual technology, i.e., incineration, to centralized and decentralized AD with different biogas applications: electricity generation, cooking fuel, and transportation fuel. The results showed that AD scenarios were generally preferable compared to incineration since environmental benefits were observed in seven to fourteen categories for AD scenarios but only four categories for incineration. The decentralized AD with biogas as cooking fuel (Sc_DADcook) achieved the highest environmental benefit in global warming potential (GWP, −238.4 kg CO2 eq./FU) and fossil fuel depletion potential (FFP, −93.5 kg oil eq./FU) among all the analysed scenarios, followed by centralized AD with biogas as transportation fuel (Sc_CADtran). The sensitivity analysis of the different electricity substitution showed that Sc_DADcook and Sc_CADtran lost their advantages when coal-dominated electricity was used, while biogas for electricity generation became favourable with higher environmental savings up to 280% and 150% in GWP and FFP, respectively. Besides, maximizing the methane yield and minimizing the FW collection radius were also identified as important measures to improve the overall environmental performance. Finally, the scenario analysis of different biogas upgrading technologies demonstrated the GWP advantage by membrane separation and benefits in other categories by high pressure water scrubbing. However, biological upgrading needs further optimization particularly of the H2 source associated emissions.

Improving high-pressure water scrubbing through process integration and solvent selection for biogas upgrading

Biogas plays a vital role in many renewable and sustainable energy strategies, where CO2 removal is required to produce biomethane (i.e., biogas upgrading). New ideas and technologies have been proposed to improve the process efficiency of biogas upgrading with liquid absorbents, and ionic liquids have been identified as promising candidates. Meanwhile, there is an urgent need to effectively utilize low-quality waste heat in industry. In this study, two strategies (i.e., waste heat integration and desorption unit modification) were proposed and compared with the original high-pressure water scrubbing; in addition, the effects of the temperatures of the heat source and solvents on the energy usage and cost were further investigated. The results showed that the total cost of the process integrated with waste heat recovery decreased by 6.2% compared with the original high-pressure water scrubbing, and the higher temperature of the waste heat source corresponded to a lower cost. The comparison of different solvents further confirmed that ionic liquid-based solvents were promising, with a potential cost reduction of 24.7%; the properties of the solvent, such as the CO2 absorption capacity, selectivity, and viscosity had significant influences on the total cost, and a new and single index “comparative absorption factor” was proposed to reflect the overall impact of these properties on the cost.

Techno-economic and environmental assessment of the main biogas upgrading technologies

Five biogas-to-biomethane upgrading technologies were compared from the environmental and economic points of view: High-Pressure Water Scrubbing (HPWS), Amine Scrubbing (AS), Potassium Carbonate Scrubbing (PCS), Pressure Swing Adsorption (PSA) and Membrane Permeation (MP). Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) methods were used for the comparison. In order to provide a wider picture of the conversion system and its impacts, the biogas production processes, starting from source sorted organic fraction of municipal solid waste, were included. The intention was to maintain the same object for the LCA and the LCC, given that the cost of biogas production had to be included for the calculation of the economic indicators. The cost analysis included also the evaluation of the external costs, derived from the monetization of the air emissions of the systems. The selected functional unit was the upgrading of 1 Nm3 of raw biogas. Data were collected directly from companies providing upgrading plants and confirmed by literature review. A biogas-to-biomethane plant proved to have environmental and economic benefits and, as expected, for larger plant sizes the economic performances improved. AS showed the best environmental performances mainly due to its limited CH4 losses and lower electricity consumption. Considering the contribution from only the upgrading part, AS showed the lowest impacts for the global warming potential (GWP) indicator (respectively 13%, 1%, 23% and 3% less than HPWS, PCS, PSA and MP). However, the results changed for other impact categories: for human toxicity indicator PSA showed lower impacts compared to the other technologies, respectively 7%, 144%, 1% and 9% less compared to HPWS, AS, PCS and MP. For small size plants, HPWS proved to be slightly more cost-effective compared to other technologies. For large size plants, PCS showed the highest net present value. Moreover, the sensitivity analysis showed that the electricity consumption is a key parameter for the economic and environmental results. Its variation proved that for the 60% of cases AS was the best solution in terms of GWP, however 35% and 5% of cases respectively indicated that PCS and MP had the lowest GWP.

Thermodynamic study on aqueous polyethylene glycol 200 solution and performance assessment for CO2 separation

To develop polyethylene glycol 200 (PEG200) and aqueous PEG200 solutions (PEG200/H2O) as solvents for CO2 separation, in this study, the available thermo-physical properties of PEG200 and PEG200/H2O measured experimentally were surveyed, evaluated, and correlated with empirical equations. The solubility of CO2 in PEG200 was also surveyed, evaluated and described with the Henry's law with the Poynting correction, while the solubilities of CH4 and N2 in PEG200 were determined experimentally and then described with the Henry's law. The CO2, CH4 and N2 solubilities in PEG200/H2O were measured and described with the Redlich–Kwong Nonrandom-Two-Liquid (RK-NRTL) model. In addition, the performances of PEG200, PEG200/H2O and other commercialized physical solvents for CO2 separation were discussed based on the properties, and the biogas upgrading was chosen as the example to quantitatively evaluate the performances of PEG200 and PEG200/H2O with process simulation and compared with the high pressure water scrubbing (HPWS). It shows that the total energy usage and the amount of recirculated solvent for biogas upgrading can decrease by 9.1% and 26.5%, respectively, when H2O is replaced by PEG200 completely.

A Life Cycle Assessment of Biomethane Production from Waste Feedstock Through Different Upgrading Technologies

Upgrading consists of a range of purification processes aimed at increasing the methane content of biogas to reach specifications similar to natural gas. In this perspective, an environmental assessment, based on the Life Cycle Assessment (LCA) method, of different upgrading technologies is helpful to identify the environmental characteristics of biomethane and the critical steps for improvement. The aim of this work is to conduct an LCA of biomethane production from waste feedstock, using the SimaPro software. The study focuses on the comparison of several upgrading technologies (namely, membrane separation, cryogenic separation, pressure swing adsorption, chemical scrubbing, high pressure water scrubbing) and the on-site cogeneration of electricity and heat, including the environmental benefits deriving from the substitution of fossil-based products. The results show a better environmental performance of the cogeneration option in most of the impact categories. The Fossil resource scarcity is the impact category which is mainly benefited by the avoided production of natural gas, with savings of about 0.5 kg oil eq/m3 of biogas for all the investigated technologies, with an average improvement of about 76% compared to conventional cogeneration. The results show that the membrane upgrading technology is slightly more environmentally convenient than the other upgrading technologies.

Single-step purification of raw biogas to biomethane quality by hollow fiber membranes without any pretreatment – An innovation in biogas upgrading

Abstract Herein, a radical innovation in biogas production is presented using a single-step membrane purification technology without any necessary pretreatment steps for contaminant removal and with the usage of low feed pressure. Asymmetric hollow fiber membranes with a thin, selective, non-porous layer made from polyester carbonate on the bore side were successfully used in a single-step raw biogas upgrading process at biogas plant Choťovice in the Czech Republic. A double-stage arrangement operated at 17 °C exhibited the best CO2/CH4 separation factor (β ∼ 23) with 96 vol% CH4 purity. This single-step biogas upgrading technology with highly H2S and water-resistant membrane modules allows reductions in capital expenditures of ∼20% and in operational expenditures of ∼50% compared to high-pressure water scrubbing (HPWS) and ∼70% compared to pressure swing adsorption (PSA). Due to the small energy consumption required merely for biogas compression, our units consumed around only ∼2 MJ/Nm3 CH4. Thus, our approach with significantly improved performance and robustness of the membrane separation process can be seen as a major breakthrough of membrane gas separation for inexpensive biogas production.

Performance evaluation of biogas upgrading by pressurized water scrubbing via modelling and simulation

The water scrubbing of biogas is an efficient, cheap and environmental friendly process to remove CO2 from biogas in order to upgrade it into biomethane. This work deals with the modelling and simulations of a scrubber-flash-stripper high pressure water scrubbing process, which is currently the most mature technology. The model and its associated simulation procedure can be used to estimate appropriate device sizes as well as to assess the performance of a given plant. Thanks to this tool, an optimized configuration is computed for a reference case. A sensitivity analysis is also realized in term of scrubbing efficiency and CH4 slippage. The influence of parameters related to the water recycling as well as the operating parameters is investigated. Moreover, the sensitivity of the model with respect to the solubility and transfer coefficient parameters is analyzed, in order to gain insight on the parameter to focus in the framework of a model calibration by experimental results.

Power requirements of biogas upgrading by water scrubbing and biomethane compression: Comparative analysis of various plant configurations

Biogas upgrading by water scrubbing followed by biomethane compression is an environmentally benign process. It may be achieved using various plant configurations characterised by various power requirements with associated effects on biomethane sustainability. Therefore, the current study has been undertaken to systematically investigate the power requirements of a range of water scrubbing options. Two groups of water scrubbing are analysed: (1) high pressure water scrubbing (HPWS) and (2) near-atmospheric pressure water scrubbing (NAPWS). A water scrubbing plant model is constructed, experimentally validated and simulated for seven upgrading plant configurations. Simulation results show that the power requirement of biogas upgrading in HPWS plants is mainly associated with biogas compression. In contrast, in NAPWS plants the main power is required for water pumping. In both plants the compression of the biomethane from atmosphereic pressure to 20MPa also contributes remarkably. It is observed that the lowest specific power requirement can be obtained for a NAPWS plant without water regeneration (0.24kWh/Nm3 raw biogas) but this plant requires cheap water supply, e.g. outlet water from a sewage treatment plant or river. The second is HPWS without flash (0.29kWh/Nm3 raw biogas). All other HPWS with flash and NAPWS with water regeneration plants have specific power requirements between 0.30 and 0.33kWh/Nm3 raw biogas. Biogas compression without upgrading requires about 0.29kWh/Nm3 raw biogas. The thermodynamic efficiency of biogas upgrading is between 2.2% and 9.8% depending on the plant configuration while biomethane compression efficiency is higher, about 55%. This result implies that the upgrading process has a remarkable potential for improvement whereas compression is very close to its thermodynamic limit. The potential for minimising energy dissipation in the state-of-the-art HPWS upgrading plant with flash by applying a rotary hydraulic pumping device is evaluated at about 0.036kWh/Nm3 raw biogas meaning the specific power requirement reduction of 10%.

Biomethane production system: Energetic analysis of various scenarios

The energy consumption models of biomethane production system were established, which are more rigorous and universal than the empirical data reported by previous biomethane system energetic assessment work. The energy efficiencies of different scenarios considering factors such as two digestion modes, two heating modes of digester, with or without heat exchange between slurry and feedstock, and four crude biogas upgrading technologies were evaluated. Results showed the scenario employing thermophilic digestion and high pressure water scrubbing technology, with heat exchange between feedstock and slurry, and heat demand of digester supplied by the energy source outside the system has the highest energy efficiency (46.5%) and lowest energy consumption (13.46MJth/Nm3CH4), while scenario employing mesophilic digestion and pressure swing adsorption technology, without heat exchange and heat demand of digester supplied by combusting the biogas produced inside the system has the lowest energy efficiency (15.8%) and highest energy consumption (34.90MJth/Nm3CH4).

Modeling and simulation of high pressure water scrubbing technology applied for biogas upgrading

Depending on the end of use, the quality of biogas must be upgraded in order to utilize the maximum amount of energy necessary for proper applications. Upgrading biogas refers to the increase of methane concentration in product gas by removal of CO2, which increases its heating power. Several treatment technologies are available for biogas upgrading: high pressure water scrubbing (HPWS), pressure swing adsorption, membrane separation, chemical absorption, and gas permeation. Water absorption based on the physical effect of dissolving gases in liquids (HPWS) is a well-known technology and the most effective upgrading process, since provides a simultaneous removal of CO2 and H2S. This could ensure an increasing methane concentration and energy content per unit volume of biogas. In spite of this, few studies are published on biogas upgrading using pressurized water technology. In order to elucidate the performance of HPWS technology at industrial scale with the possibility of water regeneration and recirculation, effects of different operating parameters on the removal of undesired components from biogas were examined, based on modeling and simulation tools. For simulation, the commercial software tool Aspen Plus was applied. Equilibrium model was applied for simulating the absorption process. The simulation results were validated with experimental data from the literature. The results are summarized in terms of system efficiency, expressed as CH4 enrichment, methane loss, and CO2 removal. Finally, new data which can be further applied for scale-up calculations and techno-economic analysis of the HPWS process are provided.

Potential CO2 savings through biomethane generation from municipal waste biogas

An alternative source of methane that can also reduce the greenhouse gas effect is one that comes from the upgrading of biogas. This paper studies eight technologies through life cycle assessment (LCA). Six of the technologies are ones that are already on the market and the two others are novel technologies that use carbon mineralization to store CO2 upon their removal. The two novel technologies include alkaline with regeneration (AwR) and bottom ash upgrading (BABIU). These technologies use waste rich in calcium, from municipal solid waste incinerators (MSWI), to store the CO2 from biogas. Among all conventional technologies, high pressure water scrubbing and chemical scrubbing with amine had the lowest CO2 impacts. Of the novel technologies BABIU saves 10% more CO2 than AwR. An uncertainty analysis and a material flow analysis demonstrated that proximity to a MSWI is an important factor to consider. As well, it was seen that while the technology is promising it cannot be applied to an entire country if the proper infrastructure is not in place.