Hand hygiene knowledge,attitudes and practices among food handlers at primary schools in Hulu Langat district,Selangor (Malaysia)

The purpose of this study was to investigate the hand hygiene knowledge, attitudes and practices of food handlers from 38 primary schools in Hulu Langat district, Selangor State in Malaysia. Hand hygiene knowledge, principally regarding ready-to-eat foods, the existence of bacteria and correct hand-washing methods were lacking among the food handlers. From the observations reported herein, the use of masks and hand-washing with proper technique were neglected by most food handlers. In the demographic profile analysed, there were significant differences (p ≤ 0.05) in the following areas: hand-washing practices between genders (p = 0.039), hand hygiene attitudes and glove use between nationalities (p = 0.002 and p = 0.029, respectively); and personal hygiene knowledge between groups with different levels of education (p = 0.048). This study revealed a slightly positive relationship between hand hygiene knowledge and self-reported practices of food handlers (r = 0.249, p = 0.022). The results showed that further continuous effort should be invested in hand hygiene education and enforcement for food handlers from primary schools in the Hulu Langat district. This study provided data about the current knowledge, attitudes and practices of food handlers from institutional foodservice operations in Malaysia regarding hand hygiene.     

Food safety knowledge and training participation are associated with lower stress and anxiety levels of Brazilian food handlers

The objectives of this study were: 1) identify the state anxiety, trait anxiety levels and perceived stress levels of food handlers and; 2) Verify the association of these scores with food safety variables like: food safety knowledge, attitudes, practices and with job characteristics. This study involved 183 randomly selected food handlers from different food businesses in Santos city, Brazil, as follows: street food kiosks, beach kiosks, restaurants, hospitals and school meal services. To evaluate knowledge, attitudes and self-reported practices, a structured questionnaire was used. Observed practices were evaluated using a checklist. The State Trait Anxiety Inventory – STAI was applied to assess the levels of state and trait anxiety with a score range from 10 to 80. To evaluate stress the Perceived Stress Questionnaire – PSQ was used with a score range from zero to one. Food handlers presented 39.22; 10.1 (mean; standard deviation) of state anxiety score, 39.58; 9.6 of trait anxiety score and a perceived stress score of 0.36; 0.09. Observed practices presented a weak negative correlation with state anxiety (r = −0.26; p = 0.014) but not with trait anxiety (r = −0.18; p = 0.09) and stress (r = 0.03; p = 0.78). Using generalized linear models were observed that a higher stress level, trait anxiety and state anxiety were found in food handlers who do not participated in food safety training and with lower knowledge scores of food safety. These findings show that training can not only improve knowledge but possibly empower food handlers, increase their self-efficacy and reduce anxiety and stress levels.     

The role of theoretical food safety training on Brazilian food handlers' knowledge,attitude and practice

The objectives of this study were 1. to identify the relationship of theoretical training with knowledge, attitudes, self-reported practices and observed practices and 2. to identify variables that influence observed practices. This study was cross-sectional and involved 183 randomly selected food handlers from different food businesses in Santos City, Brazil, as follows: street food kiosks, beach kiosks, restaurants, hospitals and school meal services. To evaluate knowledge, attitudes and self-reported practices, a structured questionnaire was used. Observed practices were evaluated using a checklist. A researcher observed and followed each food handler throughout the process of food handling/preparation during a workday. The majority of participants (68.3%) had participated in at least one food safety training session. The average percentage of correct answers on the knowledge questionnaire was 64%. Food handlers who had undergone training presented higher knowledge scores but did not differ from those who had not regarding attitudes, self-reported practices and observed practices. A regression model was used to study the variables associated with observed practices (p < 0.001). The variables related to observed practices were the knowledge score (β = 0.27, p < 0.01), experience (in years as a food handler) (β = 0.19, p = 0.01), the relationship between the number of meals and the number of food handlers (β = −0.19, p = 0.01), buildings and facilities adequacy (β = 0.20, p = 0.01) and the presence of a nutritionist (β = 0.42, p < 0.001). This study showed that training based on theoretical aspects is not related to the attitudes, self-reported practices and observed practices of Brazilian food handlers from different food services. However, training seems to be an effective tool for improving knowledge. The current wording of Brazilian legislation motivates food handlers to undergo training only for certification. Food safety laws should not only require certification but also enable the establishment of policies to monitor and ensure the adequacy of food services.     

Food safety and handling knowledge and practices of Lebanese university students

The aim of this study was to assess the level of food safety handling knowledge and practices among 1172 Lebanese university students (mean age 20.0 ± 1.6 SD) and to explore the association between their knowledge/practices and the socio-demographic and academic characteristics. Participants were undergraduate students enrolled in the Lebanese American University from different majors and years of study, from different areas of residence, living alone or with others, and having working or non-working mothers. They completed a questionnaire of 16 food handling practices and 14 food safety knowledge questions related to preparation, cross-contamination, storage and hygiene. On average, the students scored 53.6 ± 15.8% and 44.7 ± 14.3% on the knowledge and practices parts, respectively. Female students scored higher on both practices and knowledge questions than male students; however, the difference was significant (p < 0.001) for the practices part only. Health-related majors scored significantly (p ≤ 0.001) better on both practices and knowledge questions. Senior students scored highest on the knowledge questions, followed by juniors, sophomores and finally freshmen and the difference was borderline significant (p = 0.07). The area of residence had a significant (p = 0.006) effect on the food safety practices questions. Students living with parents scored higher in both knowledge and practices parts than those living alone or with roommates; howkver, the difference was significant (p = 0.009) in the knowledge part only. Students who cook all the time showed a significant (p = 0.001) lower difference in terms of their food safety knowledge compared to those who cook less frequently. Food handling practices and food safety knowledge scores were significantly (p < 0.001) related with a weak to moderate correlation coefficient (R = 0.231). Our results confirm the need for ongoing educational initiatives to improve the relatively low food awareness among the Lebanese young adults group.     

Knowledge,attitudes and practices of food handlers on food safety in food service operations at the Universiti Kebangsaan Malaysia

This study was conducted to determine the level of knowledge, attitudes and practices of food handlers in food service operation at the main campus of Universiti Kebangsaan Malaysia (UKM) regarding food safety. Data were collected from 112 food handlers through questionnaires which consisted of questions about knowledge, attitudes and practices. The results showed that there was significantly positive correlation among the three levels and respondents possess good scores for knowledge (19.68 ± 3.87) about personal hygiene, foodborne diseases and temperature control of food; for attitudes (89.26 ± 8.66) on safe food handling, and for practices (90.02 ± 8.23), specifically for appropriate hand washing, use of gloves in food preparation and prevention of food hazards. About 73.2% of respondents never attend any training related to food safety and majority show poor knowledge of pathogens associated with disease-causing agents as well as critical temperatures for storage of ready-to-eat foods. Therefore, effective and ongoing training on food safety and hygiene must be given to all food service employees to ensure the safety of food provided.     

Food safety knowledge,attitudes and self-reported practices of food handlers in institutional foodservice in Accra,Ghana

The aim of this study was to evaluate the food safety knowledge, attitude and practices (KAP) of food handlers from institutional food service establishments that serve hospitals, boarding senior high schools and prisons in Accra, Ghana. A total of 278 food handlers (56.8% of hospital, 30.9% of schools and 12.3% of prison food service) participated in the cross-sectional study. Data was collected by face-to-face interviews, and responses were scored to determine the level of food safety KAP. Respondents who scored ≥70% of the maximum possible score were adjudged to have sufficient knowledge and practices and positive attitudes. Results showed that respondents generally had insufficient food safety knowledge and practices with means scores of 20.99 ± 7.64 (46%) and 9.35 ± 5.62 (52%) respectively. Attitudes towards food safety were generally negative but with a comparatively higher mean score of 12.64 ± 3.06 (63%). Areas of most concern were 1) Lack of knowledge of sources of contamination/cross-contamination and appropriate holding temperatures for food. 2) Poor practices included multiple freeze-thaw cycles for frozen food and 3) Infrequent hand washing during food preparation after coughing or sneezing. There is the need for continuous risk based training to educate and effect behavioral changes among food handlers. This process will encourage positive attitudes towards food safety and consequently promote good food safety practices.     

Food safety knowledge,attitudes and practices of street food vendors and consumers in Ho Chi Minh city,Vietnam

This study had the major objective of evaluating the food safety knowledge, attitudes and practices of consumers and vendors of street foods in Ho Chi Minh City (MCMC), Vietnam. There were three main surveys performed in this study. A total of 120 consumers and 40 street food vendors from four districts [Binh Thanh (BT), Thu Duc (TD), district 3 (D3) and district 8 (D8)] in HCMC contributed to the study on a voluntary basis. The surveyed consumers had adequate levels of food safety knowledge and attitudes. No significant difference (p > 0.05) occurred between the food safety knowledge levels of the consumers on the basis of gender. However, significant differences (p < 0.05) occurred on the basis of age, education level, food safety training status and location. In contrast, the street vendors had poor food safety knowledge and attitude levels. No significant differences (p > 0.05) were observed in the food safety knowledge levels of the vendors on the basis of gender and age. However, significant differences (p < 0.05) were found on the basis of food safety training status and education level. It was also noted that the vast majority (95%) of the vendors had not received any food safety training. With regards to the practices, it was determined that 52.5% of the vending sites were open air stands without any protection from the sun, wind and dust. 52.5% the vending stalls had no direct access to potable water, while 47.5% did not have adequate hand washing facilities and a further 30% lacked proper waste water and food disposal facilities. In addition, 52.5% of the vendors did not separate raw, partially cooked food and cooked food products. These findings highlighted that street food vendors in HCMC generally have poor food handling practices and most are operating under unhygienic conditions. These results should provide the Vietnamese government with even more reasons to increase their current efforts to improve the safety of street foods and food safety awareness of the consumers.     

Food safety knowledge of foodservice workers at a university campus by education level,experience, and food safety training

Food safety knowledge of university foodservice workers was evaluated and the relationship between food safety knowledge and education level, length of employment, and food safety training was assessed using a 40-item food safety questionnaire. Each knowledge question was scored as “1” for a correct answer and as “0” for an incorrect answer. The relationships between the level of education and food safety knowledge scores and length of employment in the foodservice industry and food safety knowledge scores were determined using bivariate correlation analysis. A total of 63.5% of the respondents had limited knowledge, 79% were well-informed about hygiene practices, while 33.9% of persons knew of correct time-temperature control measures. Kendall's tau = 0.067; p = 0.294 revealed a lack of strength of the relationship between education level and food safety knowledge. The relationship between length of employment and food safety knowledge was Kendall's tau = −0.133; p = 0.121. No mean differences (p = 0.426) were observed for mean knowledge scores between groups of food safety trained and untrained persons. Neither education level, nor the length of employment in the foodservice industry had a significant impact on food safety knowledge. The authors recommend that in order to improve food safety knowledge, attention should be given to the planning, implementation, monitoring, and evaluating food safety education programs.     

Process manages and hygienic practices of local beverages producers and sellers in Ouagadougou,Burkina Faso

The trade of local beverages and ice has become popular in many developing countries including Burkina Faso. This study was performed to determine the local beverages safety knowledge of producers and sellers in Ouagadougou. Face-to-face interviews of 233 producers and sellers were conducted. The approach used concerned the process of good hygiene and production. The data were collected following observation checklists and an adapted set of questions: knowledge of risk perception, training, personal hygiene, cleanliness of the selling site, water supply, refreshment condition, packaging materials, food handling practices and foodborne pathogens. Data were analysed by using means, frequencies, standard deviation, 95% confidence interval and t-test. The results of survey showed that women represent 94% of 233 total sellers. Eighty five percent 85.4% did not receive appropriate training about food hygiene and 72.5% of them did not know the reasons of local beverages and ice contamination. Only 35.6% of the sellers used freeze system to store beverages. Poor quality of water and hands implicated to local beverage manufacturing were respectively assigned 8.6% and 7.3%. Statistical analyses revealed significant difference (P < 0.05) between hygiene training and stationary sellers (P = 0.004), hygiene training and source of water (P = 0.02), hygiene training and cold chain (P = 0.013). In view of the socio economic importance of local beverages and their role in the unexpected arrival of food-borne diseases, local beverages sellers should be regularly trained, retrained in order to prevent outbreaks of food-borne illnesses.     

The evaluation of food hygiene knowledge,attitudes, and practices of food handlers’ in food businesses in Turkey

The purpose of this study was to evaluate knowledge, attitudes, and practices concerning food safety issues among food handlers in Turkey, conducting face to face interview and administrating questionnaire. Of the 764 food handlers who responded, 9.6% were involved in touching or distributing unwrapped foods routinely and use protective gloves during their working activity. A majority of participants (47.8%) had not taken a basic food safety training. The mean food safety knowledge scores was 43.4 ± 16.3. The study demonstrated that food handlers in Turkish food businesses often have lack of knowledge regarding the basic food hygiene (critical temperatures of hot or cold ready-to-eat foods, acceptable refrigerator temperature ranges, and cross-contamination etc.). There is a immediate need for education and increasing awareness among food handlers regarding safe food handling practices.     

Prevalence of Salmonella typhi and intestinal parasites among food handlers in Mekelle University student cafeteria,Mekelle, Ethiopia

Food borne diseases are one among the most significant factors affecting public health related issues globally. The related problems are high in the developing countries, due to the difficulties in adopting optimal hygienic practices during food handling. The aim of this study was to evaluate the prevalence of Salmonella typhi and intestinal parasites in the stool samples of food handlers in Mekelle University student cafeteria, in the city of Mekelle, Ethiopia. Food handlers, infected or carriers plays a role in the transmission of infections to the public especially in the society, community and to the patients in hospitals. A cross sectional study was conducted during the period of December 2012 to August 2013. Stool samples were collected from 307 food handlers in the student's cafeteria. Microscopic examination and culturing of the samples were performed for the isolation of intestinal parasites and Salmonella species, respectively. Out of the 307 food handlers enrolled in the study, one hundred sixty one (52.4%) stool specimens were positive for different intestinal parasites. Entamoeba histolytica/dispar was the most prevalent parasite (32.3%), followed by Giardia lamblia (4.9%) and Schistosoma mansoni (2.6%). In which four (1.3%) stool specimens were positive for mixed parasites. Only three (1%) S. typhi were isolated from the food handlers and evaluated for antibacterial sensitivity pattern against the commonly used antibiotics. Statistically significant analysis was seen between the intestinal parasite and sex (X² = 6.603, df = 1, P = .007), year of service (X² = 21.2, df = 6, P = .002) and level of education (X² = 11.779, df = 4, P = .019). Our investigation reveals that there is high prevalence of enteric pathogens among food handlers which indicates the improper hygienic practices and no standard protocols among the food-handlers who are working in the student's cafeteria. Hence, proper educations, protocols, training programs on the hygienic practices and regular medical checkup among food-handlers will help to control the prevalence of intestinal pathogens and parasites at certain limits.     

Educational needs assessment and practices of grocery store food handlers through survey and observational data collection

Grocery store associates in deli/bakery departments prepare and serve an increasing number of ready-to-eat (RTE) foods and full meals. The shift to more convenience foods and take-home meals highlights the need for effective food safety training programs in retail grocery establishments to prevent foodborne illness. Through qualitative and quantitative methods, food safety knowledge, training preferences, needs, and current practices of grocery stores deli/bakery food handlers in Southwest and Southern Virginia were explored. Deli employees (n = 78) completed a 34 question survey eliciting information on demographics, food safety training needs, preferences and knowledge. In an additional phase of this project, a subset of those originally surveyed (n = 15) were observed for food handling practices (6 h per person). Observational data collection focused on cross-contamination, glove use and hand washing. Most grocery store deli/bakery food handlers reported wanting frequent hands-on, interactive one-on-one training lasting less than 2 h. The target audience's largest knowledge gaps included correct temperatures for cooking, reheating and cooling foods. Observed behaviors did not correlate with food safety knowledge. For example, greater than 95% of participants reported using correct hand washing techniques; however, observational behavior data showed less than 50% of hand washing events observed were correct. Additionally, food handlers were observed not washing hands prior to putting gloves on as well as practicing bare hand contact with RTE foods. The creation of short, hands-on or interactive trainings for retail grocery food handlers that focuses on changing food handling and preparation behaviors may enhance the food handler's safe food handling practices.     

Food safety knowledge,attitudes and practices of street food vendors and consumers in Port-au-Prince,Haiti

This study had the major objective of determining the food safety knowledge, attitudes and practices of vendors and consumers of street food in Port-au-Prince, Haiti. Haiti currently has no food safety legislation in place. 160 consumers and 80 vendors from four different communes (Tabarre, Delmas, Pétion-ville and downtown Port-au-Prince) volunteered to participate in the study. In general, consumers and vendors exhibited average food safety knowledge and attitude levels. Gender, training, level of education and location did not have a significant effect (p < 0.05) on the level of food safety knowledge of the consumers. Vendors were determined to have higher levels of food safety knowledge than consumers, whilst trained vendors had better food safety knowledge and attitudes compared to untrained vendors. The majority of vendors and consumers were aware of the importance of washing hands and proper cleaning with regards to the prevention of foodborne diseases. However, some other aspects were of concern. Consumers and vendors did not know that Hepatitis A, Salmonella spp. and Staphylococcus spp. are pathogens responsible of foodborne diseases. They also had difficulties in identifying the groups at risk of foodborne diseases and most were unaware of the importance of reheating food to fight against foodborne diseases. In the observational part of the study, it was found that in 60% of the cases, flies and animals were evident around the stall and 65% did not have access to potable water. The majority served food with bare hands and did not wash their hands after handling money. Additionally, 70% of the vendors did not chill pre-cooked food. The conditions in which street food vendors operate in Port-au-Prince are largely unacceptable from a food safety point of view and an effort should be made to provide them with adequate infrastructure including potable water, toilets and waste disposal facilities. The results of this study should be used to generate part of the impetus towards the development of enforcement of appropriate food safety legislation in Haiti.     

On the determination of the skin factor and the turbulence term coefficient through a single constant gas pressure test

The best correlation for evaluating the turbulence term coefficient, D(μ), for transient flow in gas wells under constant flow rate conditions is currently that of Lee et al. [Lee, R.L., Logan, R.W., Tek, M.R., 1987. Effect of turbulence on transient flow of real gas through porous media. SPE Form. Eval. (March), 108–120]. Several authors have used this correlation to calculate the production decline for wells that produce under constant bottomhole pressure conditions, but it is not clear if this is correct. When exploiting any gas reservoir, the flow rate and the average reservoir pressure decrease with time. This process makes D(μ) increase, whereas D(μ)q_sc decreases with time; in contrast, when a well is produced under constant flow rate conditions, D(μ)q_sc increases with time. Due to this fact, it can be of considerable practical interest to analyze the behavior of the high velocity pseudoskin factor, D(μ)q_sc, for gas wells that produce under constant bottomhole pressure conditions. This paper presents the results of a study aimed at obtaining a correlation of both the mechanical skin factor, s, and the turbulence term coefficient, D(μ), for constant bottomhole pressure conditions through the analysis of a single test. Results obtained through a radial real gas flow simulator, carefully validated for pseudosteady state conditions were used as a database for the development of the new correlations. The skin effect considered varies from 0 to 10. Two different gases are considered. Other variables studied are the constant pressure, the reservoir size r_e/r_w and formation permeability. The correlation is presented by means of straight-line fits of s_t/[s(1−r_w/r_d)] in the vertical axis and D(μ_i)q_sc in the horizontal axis. The correlation coefficient was 0.9976. The error obtained when one evaluates the skin factor, s, using the correlation presented in this work is less than 10%. The error is substantially less when production rates are low. These rates strictly correspond to the case of low permeability reservoirs, where the constant pressure boundary condition considered is this study closely apply.     

Food safety knowledge and practices among Saudi women

The present cross sectional study was conducted on 811 Saudi women to evaluate their food safety knowledge and practices and explore factors affecting them. They reported better food safety practices than knowledge in overall food safety and all parameters except cooking. Personal hygiene was the parameter where they reported higher mean knowledge and practice (63.4% and 73.8%; respectively) with the lowest mean knowledge score in utensils and equipment (49.8%) whereas the lowest mean practice (60.2%) was in cooking. Saudi women with higher studies and those with 60 years and more showed higher mean knowledge and practice score in overall food safety and most parameters than those in other educational levels or age groups with significant variations (P < 0.05) among different educational levels except in practicing personal hygiene. Working women showed higher mean knowledge and practice than non working in all parameters with significant variation between their mean knowledge scores except in personal hygiene. Launching a food safety education program and repeating it at specific intervals is recommended.     

Food safety knowledge and food-handling practices of Greek university students: A questionnaire-based survey

A survey was conducted to assess the self-reported food safety knowledge and food-handling practices of Greek young adults (mean age 22.4 ± 3.2 standard deviation, SD) and to explore the relationships between their food safety awareness and population characteristics. Participants were senior undergraduate students recruited from health-related and non-health-related faculties of the Aristotle University of Thessaloniki in Northern Greece. They completed a questionnaire containing sixteen food safety knowledge and sixteen food-handling questions grouped into four subsections: food microbiology/cross-contamination, food preparation (cooking), food storage (chilling), and cleaning/hygiene. Students correctly answered only 38% of food handling (mean number of correct responses = 6.0, SD = 2.4) and 37% of food safety knowledge questions (mean number of correct responses = 5.9, SD = 2.9). In general, students seemed to adhere to best practices as regards hand washing and prevention of cross-contamination but very few reported the use of food thermometers during cooking. Participants were, usually, knowledgeable about the impact of freezing on bacteria but not about common food vehicles of foodborne pathogens. Students from faculties delivering health-related programs significantly outperformed those from humanity-sciences programs, on both food safety knowledge and practice outcomes. Females obtained considerably better food-handling scores than males even though the overall food safety knowledge score was similar for males and females. An educational background relevant to food safety was a significant predictor of responding accurately to a wide range of study questions. These results substantiate the need for educational initiatives tailored to develop the food safety knowledge and food-handling practices of young Greek consumers.     

Food safety awareness,knowledge and practices among students in Slovenia

It is critical for children to understand food-related risks to preserve their health and the health of others, particularly because their food preparation responsibilities will increase in adulthood. The purpose of this study (n = 1272) was to explore the inclusion of 10- to 12-year-old students in food preparation activities and to determine their understanding of food-related risks, food safety knowledge and self-reported practices in their domestic environment prior to systematic involvement in these activities during regular schooling. This study highlighted their inclusion in food preparation activities with limited experiences. For food-related risks, a high level of perceived severity and a low level of perceived vulnerability were observed. Particular lack of knowledge was identified regarding the impact of temperature on microorganisms. Additionally, self-reported practices indicated risky behaviours for the prevention of cross-contamination, preservation of leftovers, re-heating of food in a potentially unsafe manner and food preparation activities with unprotected wounds on their hands. These results demonstrate that the systematic teaching of basic food safety principles as early as primary school remains necessary.     

Quantification and variability of Escherichia coli and Staphylococcus aureus cross-contamination during serving and consumption of cooked thick porridge in Lungwena rural households, Malawi

The study investigated bacterial transfer to cooked thick porridge via ladles and hands during serving in 29 households in Lungwena, rural Malawi. Household stored water used for hand and ladle washing, was contaminated with Escherichia coli and Staphylococcus. aureus from hands of members of the household or from contaminated ladles used in food preparation. The results showed that hands became contaminated with E. coli and S. aureus cells in the range 0.6–3.7 and 2.2–4.3 log₁₀ CFU/cm², respectively, following washing with the contaminated water. Ladles became contaminated with 0.9–3.2 log₁₀ CFU/cm² of E. coli cells whereas contamination with S. aureus on ladles ranged between 1.9 and 4.6 log₁₀ CFU/cm². Bacterial transfer from hands to food ranged from <1 to 3.6 log₁₀ CFU/g for E. coli and 2.1 to 4.2 log₁₀ CFU/g for S. aureus. Ladle surfaces transferred from 1.3 to 3.1 and from 1.2 to 4.3 log₁₀ CFU/g of E. coli and S. aureus, respectively, on to the food. Contamination of food by hands was significantly (p < 0.05) higher than that of ladles and transfer of S. aureus was significantly (p < 0.05) higher than that of E. coli. The amount of bacteria transferred to the recipient depended on the wash water type and bacteria type. The study has demonstrated that although the traditional cooking of thick porridge inactivates S. aureus and E. coli, the porridge can be contaminated with bacteria during consumption using hands and serving on to a plate with wooden ladles.     

Transient gas–liquid two-phase flow in pipes with radial influx or efflux

A simplified model for transient gas–liquid flow in pipes with radial influx or efflux has been developed in this paper. The resulting governing equations are essentially hyperbolic with U_tp+c_s and U_tp−c_s as their eigenvalues. A finite-difference scheme based on the split coefficient matrix (SCM) approach is applied to solve the mass and momentum balance equations. Sample numerical simulation runs are performed. Simulation results agree with experimental observations and clearly show the features of variation in pressure drop, liquid holdup, and two-phase velocity during transient and steady state flow periods.     

Application of prediction models to performance of high paraffinic content oilfields: Case study Shen95 Block of Jinganbao Oilfield

Production performance was curve-fitted for prediction of production and estimation of incremental recovery for waterflooded reservoir. Arguably, simulation may yield non-unique solution or fail due to assumptions on the true effect of high-paraffin content on porosity, saturation, and fluid rheology in the entire formation caused by temperature and solubility effects. The curve-fitting models applied are Arps' rate–time models and Li–Horne mechanistic model proven applicable to waterflooded and naturally fractured reservoirs. Others are Corrêa's volumetric oil-cut decline model tested on heterogeneous, waterflooded, high viscous and heavy oil reservoirs characterized by volumetric-exponential decline and a water displacement curve method. The match periods for Arps' models were constrained by criteria from literature reviewed to ensure that decline was relatively under the influence of relative permeability and not operational changes. The models were chosen to match performance primarily of Shen95 Block, a faulted block in the Damintun depression, Liaohe basin, China, characterized by high pour point within 42–64 °C. Recovery estimate was not entirely consistent with past findings of Li–Horne model estimates falling in-between exponential and harmonic decline estimates, but consistent with harmonic decline estimates. Performance match preference was Corrêa's model, but the model was extended to specifically characterize performance trend by reciprocal decline exponent (β = − 2) beyond the prior considered range of (− 1 ≤ β ≤ 0). The other block considered, a naturally fractured reservoir having similar fluid properties with Shen95 was also characterized by (β = − 2). A holistic approach will require the alternate use of the models based on the strong points of each model according to theory, performance trends and operational changes.