高档卷烟纸生产废水处理的中试研究

广东某厂高档卷烟纸生产废水经单独混凝沉淀难以达标排放,采用中试规模的曝气生物滤池(BAF)对经混凝沉淀的高档卷烟纸废水进行处理,结果表明,BAF对该类废水处理的最佳水力负荷为1m3/(m2.h),此时CODCr去除率85%,TSS去除率24%,反冲洗仅需12～15天1次,出水性能优于广东省地方标准中的一级排放标准。当向调节池添加1:10比例的浓浆池废水与原调节池废水时,BAF有较强的抗冲击负荷能力,CODCr去除率仍然在80%左右,出水达标,但反冲洗为2～3天1次。研究表明,混凝沉淀+BAF处理高档卷烟纸生产废水处理是一种可行、稳定的工艺。     

高档卷烟纸生产废水处理的中试研究

广东某厂高档卷烟纸生产废水经单独混凝沉淀难以达标排放,采用中试规模的曝气生物滤池(BAF)对经混凝沉淀的高档卷烟纸废水进行处理.结果表明,BAF对该类废水处理的最佳水力负荷为1 m3/(m2·h),此时CODCr去除率85％,TSS去除率24％,反冲洗仅需12～15天1次,出水性能优于广东省地方标准中的一级排放标准.当向调节池添加1∶10比例的浓浆池废水与原调节池废水时,BAF有较强的抗冲击负荷能力,CODCr去除率仍然在80％左右,出水达标,但反冲洗为2～3天1次.研究表明,混凝沉淀+BAF处理高档卷烟纸生产废水处理是一种可行、稳定的工艺.     

差别化化学纤维生产废水处理工程的分析

本研究根据差别化化学纤维生产废水的水质特点,采用物化、生化、深度组合工艺进行处理.运行结果表明:该组合工艺对CODCr去除率达到95％以上,出水各项指标满足《城镇污水处理厂污染物排放标准》(GB18918-2002)中一级A标准,且系统运行可靠稳定、耐冲击性能强、出水效果好.     

动态膜生物反应器-混凝工艺处理草浆中段废水

采用动态膜生物反应器(DMBR)-混凝工艺对草浆造纸中段废水进行处理。结果表明,DMBR内的生物动态膜约在反应器运行60min后形成。在污泥浓度为10g/L、水力停留时间24h、进水CODCr1344mg/L、进水木素为390mg/L时,DMBR出水CODCr和木素分别平均为260mg/L和192mg/L。投加PAC对动态膜生物反应器出水进行混凝处理,当PAC用量为0.54g/L时,混凝处理出水的CODCr和木素平均为117mg/L和63mg/L。DMBR反冲洗后,反应器内生物动态膜的再生需要30min完成,稳定运行过程中DMBR的反冲洗周期能够稳定在29h以上。     

电泳涂装废水的处理

针对电泳涂装废水中含有有机物、表面活性剂、锌离子、Oil、磷酸盐离子等污染物,其废水成份复杂,浓度高,采用混凝沉淀+过滤的工艺对涂装废水进行处理,取得了良好效果:CODCr去除率大于80%。实际运行表明,该工艺在技术和经济上均是合理可行的。     

钙盐沉淀-混凝沉淀法处理酸性含氟工业废水

通过对某化工厂排放的酸性高浓度含氟废水进行多种方法处理的试验,最终确定采用NaOH中和、氯化钙化学沉淀,PAC二级絮凝沉淀进行处理,出水中的氟浓度可以小于4mg·L-1可以达到国家规定的一级排放标准。     

中小型制革企业生产废水全物化处理

采用以内电解为主的全物化工艺处理制革废水 ,当进水 CODCr、BOD5、SS分别为 1973mg/ L、974 mg/ L、12 98mg/ L时 ,出水水质能够稳定达到二级排放标准。本工艺特别适合间歇生产的中小型制革企业 ,具有启动速度极快 ,操作简便 ,运行稳定并受气温影响小 ,脱色效果好 ,投资低等特点     

混凝-生化-混凝组合工艺处理造纸中段废水的研究

以湖南某纸业公司的造纸中段废水为研究对象,采用混凝预处理-活性污泥-混凝组合工艺对该废水进行处理。实验采用专利产品复合型聚合硫酸铁(FPAS)为混凝剂,研究了预处理段和第三段中混凝剂的最佳用量;活性污泥处理实验包括污泥的培养、驯化和系统运行效果考察。采用混凝-活性污泥-混凝组合工艺,可使出水各项指标均达到国家排放标准(GB3544—2008)。     

混凝-生化-混凝组合工艺鸡皮疙瘩处理造纸中段废水的研究

以湖南某纸业公司的造纸中段废水为研究对象,采用混凝预处理-活性污泥-混凝组合工艺对该废水进行处理.实验采用专利产品复合型聚合硫酸铁(FPAS)为混凝剂,研究了预处理段和第三段中混凝剂的最佳用量;活性污泥处理实验包括污泥的培养、驯化和系统运行效果考察.采用混凝-活性污泥-混凝组合工艺,可使出水各项指标均达到国家排放标准( GB3544-2008).     

HACCP在乳品生产中的应用探讨

在食品的生产管理中，对其质量的预防和控制传统的做法是把重点放在监督检查和对成品的监测上，而HACCP是把预防和控制重点前移，对全过程进行危害分析，找出关键控制点并采取有效措施加以控制。在实际应系统地分析整个生产过程，确定CCP点，并制定有效的控制措施。     

Effect of bioaugmentation on anaerobic wastewater treatment in the dairy industry

The creation of a biofilm as a specialized biosystem, its development, and activity were studied at 3 critical control points of biofilter operation: start-up, transition from batch to sequencing batch regimen, and set-up of stable sequencing batch process. Five variants of biosystems were investigated with an inoculum from specially adapted real activated sludge, enriched with various combinations of 3 microbial preparations. A stable and working biofilm was developed in the phase of stabilized sequencing batch process. The differences among biodegradation effectiveness of the 5 variants were insignificant during that phase and the effect of the preparations was low. The effectiveness of organic removal for the 5 bioaugmentation approaches reached 60% for protein, 70% for chemical oxygen demand, and 97% for lactose. Commercial inocula did not improve final reactor performance over an inoculum from a municipal wastewater treatment plant alone.     

Major advances in teaching dairy production

A survey of 38 universities that grant 4-yr degrees as well as 12 institutions that grant technical degrees of 2 yr or less revealed that degree programs in dairy production remain popular, but have changed significantly over the last 25 yr. Enrollment in dairy production programs remains strong (1,189 and 417 students in baccalaureate and nonbaccalaureate degrees, respectively) even though this is viewed as a traditional industry. There are significant differences in size of programs across the United States, and some are struggling to maintain both the visibility and faculty numbers to keep pace with the industry. The percentage of students enrolled in 4-yr programs who are female has increased to the majority. More students hail from a nondairy farm background in our university programs today than in 1994. Computer and information technology has become a mainstream part of our educational programs. A high percentage of undergraduate students elect to engage in an internship or work experience, and there is a high correlation between internship and career paths selected by our students. The dairy industry initiated and financially supports the North American Intercollegiate Dairy Challenge; an educational activity among university teams to foster skills in analyzing a dairy farm business. This collaboration between universities and private industry is strong evidence that our undergraduate programs are relevant to the dairy industry. Extracurricular activities like dairy science clubs also remain popular, and are perceived by faculty members to be an important part of our educational experience. An analysis of nonbaccalaureate degree programs was not reported previously, but was a part of the present survey. In the nonbaccalaureate institutions that responded to the survey, there were 417 students enrolled in 12 dairy programs across the United States in 2004. This student population in nonbaccalaureate programs has a higher percentage of female enrollment than in 1994, but enrollment is still predominantly male. Computer and information technologies are an important part of their curricula and a very high percentage of these students remain in production agriculture upon graduation. Many of the challenges in undergraduate education described previously continue to be challenges in 2005. However, there are many reasons for optimism; as the number of students electing enrollment in dairy production remains strong, there is great interest in keeping the curricula relevant and interaction with and support by the dairy industry continues to be significant.     

Ammonia emissions from dairy production in Wisconsin

Ammonia gas is the only significant basic gas that neutralizes atmospheric acid gases produced from combustion of fossil fuels. This reaction produces an aerosol that is a component of atmospheric haze, is implicated in nitrogen (N) deposition, and may be a potential human health hazard. Because of the potential impact of NH₃ emissions, environmentally and economically, the objective of this study was to obtain representative and accurate NH₃ emissions data from large dairy farms (>800 cows) in Wisconsin. Ammonia concentrations and climatic measurements were made on 3 dairy farms during winter, summer, and autumn to calculate emissions using an inverse-dispersion analysis technique. These study farms were confinement systems utilizing freestall housing with nearby sand separators and lagoons for waste management. Emissions were calculated from the whole farm including the barns and any waste management components (lagoons and sand separators), and from these components alone when possible. During winter, the lagoons’ NH₃ emissions were very low and not measurable. During autumn and summer, whole-farm emissions were significantly larger than during winter, with about two-thirds of the total emissions originating from the waste management systems. The mean whole-farm NH₃ emissions in winter, autumn, and summer were 1.5, 7.5, and 13.7% of feed N inputs emitted as NH₃-N, respectively. Average annual emission comparisons on a unit basis between the 3 farms were similar at 7.0, 7.5, and 8.4% of input feed N emitted as NH₃-N, with an annual average for all 3 farms of 7.6 ± 1.5%. These winter, summer, autumn, and average annual NH₃ emissions are considerably smaller than currently used estimates for dairy farms, and smaller than emissions from other types of animal-feeding operations.     

Effects of heat-stress on production in dairy cattle

The southeastern United States is characterized as humid subtropical and is subject to extended periods of high ambient temperature and relative humidity. Because the primary nonevaporative means of cooling for the cow (radiation, conduction, convection) become less effective with rising ambient temperature, the cow becomes increasingly reliant upon evaporative cooling in the form of sweating and panting. High relative humidity compromises evaporative cooling, so that under hot, humid conditions common to the Southeast in summer the dairy cow cannot dissipate sufficient body heat to prevent a rise in body temperature. Increasing air temperature, temperature-humidity index and rising rectal temperature above critical thresholds are related to decreased dry matter intake (DMI) and milk yield and to reduced efficiency of milk yield. Modifications including shade, barns which enhance passive ventilation, and the addition of fans and sprinklers increase body heat loss, lowering body temperature and improving DMI. New technologies including tunnel ventilation are being investigated to determine if they offer cooling advantages. Genetic selection for heat tolerance may be possible, but continued selection for greater performance in the absence of consideration for heat tolerance will result in greater susceptibility to heat stress. The nutritional needs of the cow change during heat stress, and ration reformulation to account for decreased DMI, the need to increase nutrient density, changing nutrient requirements, avoiding nutrient excesses and maintenance of normal rumen function is necessary. Maintaining cow performance in hot, humid climatic conditions in the future will likely require improved cooling capability, continued advances in nutritional formulation, and the need for genetic advancement which includes selection for heat tolerance or the identification of genetic traits which enhance heat tolerance.     

指纹图谱技术在乳制品质量控制中的应用

指纹图谱技术是一种分析复杂组分或成品的有效、全面的分析方法。简要地介绍了指纹图谱技术的特点、研究方法以及指纹图谱的构建。重点概述了指纹图谱技术在乳制品领域中的应用,包括特征鉴定、掺假识别、质量过程控制以及微生物监测四个方面。指纹图谱技术将成为乳制品质量控制新的发展方向。     

Effect of protein degradability on milk production of dairy ewes

The objective of this experiment was to determine the effect of protein degradability of dairy sheep diets on milk yield and protein utilization across 2 levels of milk production. Three diets were formulated to provide similar energy concentrations and varying concentrations of rumen-degradable protein (RDP) and rumen-undegradable protein (RUP): 12% RDP and 4% RUP (12-4) included basal levels of RDP and RUP, 12% RDP and 6% RUP (12-6) included additional RUP, and 14% RDP and 4% RUP (14-4) included additional RDP. Diets were composed of alfalfa-timothy cubes, whole and ground corn, whole oats, dehulled soybean meal, and expeller soybean meal (SoyPlus, West Central, Ralston, IA). Estimates of RDP and RUP were based on the Small Ruminant Nutrition System model (2008) and feed and orts were analyzed for Cornell N fractions. Eighteen multiparous dairy ewes in midlactation were divided by milk yield (low and high) into 2 blocks of 9 ewes each and were randomly assigned within block (low and high) to 3 pens of 3 ewes each. Dietary treatments were arranged in a 3 × 3 Latin square within each block and applied to pens for 14-d periods. We hypothesized that pens consuming high-RUP diets (12-6) would produce more milk and milk protein than the basal diet (12-4) and pens consuming high-RDP diets (14-4) would not produce more milk than the basal diet (12-4). Ewes in the high-milk-yield square consumed more dry matter and produced more milk, milk fat, and milk protein than ewes in the low-milk-yield square. There was no effect of dietary treatment on dry matter intake. Across both levels of milk production, the 12-6 diet increased milk yield by 14%, increased milk fat yield by 14%, and increased milk protein yield by 13% compared with the 14-4 and 12-4 diets. Gross N efficiency (milk protein N/intake protein N) was 11 and 15% greater in the 12-6 and 12-4 diets, respectively, compared with the 14-4 diet. Milk urea N concentration was greater in the 12-6 diet and tended to be greater in the 14-4 diet compared with the 12-4 diet, indicating that the excretion of urea N in this study was more closely related to dietary crude protein concentration than to protein degradability.     

Hepatic triacylglycerol associations with production and health in dairy cows

The objectives were to evaluate the associations between hepatic triacylglycerol content and production, blood metabolites, incidence of diseases, reproduction, and survival in Holstein cows. Data were collected from 4 experiments including 329 cows in which hepatic tissue was sampled with a mean (± standard deviation) of 8.3 ± 1.5 d postpartum (6 to 11 d) and analyzed for triacylglycerol concentration. The mean (± standard deviation) concentration was 4.4 ± 2.8% on a wet basis and ranged from 0.4 to 16.1%. Intakes of dry matter (DM), energy balance, body weight (BW), body condition (BCS), productive performance, and incidence of diseases were evaluated for the first 105 d postpartum, whereas blood metabolites were assayed in the first 21 d postpartum. Reproductive performance and survival were monitored in the first 300 d postpartum. Mixed models were fitted to the data to investigate the linear and quadratic associations of hepatic triacylglycerol concentration with responses of interest. Increased concentration of hepatic triacylglycerol was associated with a quadratic increase in yields of milk, energy-corrected milk (ECM), and milk components. A change in hepatic triacylglycerol from 2.5 to 7.5% of the wet tissue was associated with an increase in yield of ECM of 1.8 kg/d, and with 0.2 kg more ECM per kg of DM intake. However, the increased efficiency was accompanied by decreases in DM intake, BCS, more exacerbated losses of BW, and a more negative body energy change. Increased concentration of hepatic triacylglycerol was associated with a quadratic increase in blood fatty acids and a linear increase in blood β-hydroxybutyrate concentrations, concurrent with linear decreases in concentrations of glucose and total Ca in blood. Moreover, a change in hepatic triacylglycerol from 2.5 to 7.5% was associated with linear increases in the relative risk of hyperketonemia by 2.5 times (15.2 vs. 37.5%), hypocalcemia by 1.7 times (30.3 vs. 52.4%), metritis by 2.1 times (12.5 vs. 25.7%), and diagnosis of multiple diseases postpartum by 2.4 times (8.7 vs. 21.1%). Survival in the herd by 300 d postpartum tended to decrease from 91.1 to 86.3% with an increase in hepatic triacylglycerol from 2.5 to 7.5% of the wet tissue, but no association was observed between hepatic triacylglycerol and measures of reproduction in the first 300 d postpartum. Concentrations of hepatic triacylglycerol in early lactation varied substantially, and increments resulted in quadratic association with productive performance, but at the expense of tissue reserves as those cows had increased tissue catabolism and risk of diseases that reduced survival.     

乳品加工中热交换器结垢的形成与影响因素

介绍了乳品工业中对产品的安全和设备的动转有巨大影响的结垢问题，简述了结垢的形成、影响因素及相应的预防措施。     

Organic dairy production systems in Pennsylvania: a case study evaluation

The current market demand and price for organic milk is encouraging dairy producers, particularly those on smaller farms, to consider organic production as a means for improving the economic viability of their operations. Organic production systems vary widely in scale, in practices, and across agroclimatic settings. Within this context, case studies of 4 actual organic dairy farms were used to characterize existing systems in Pennsylvania. Based on data from these farms, a whole-farm simulation model (Integrated Farm System Model) was used to compare 4 production systems representing organic grass, organic crop, conventional crop with grazing, and conventional confinement production. The performance of each of these systems was simulated over each year of 25 yr of central Pennsylvania weather data. Simulation results indicated that farm level accumulation of soil P and K may be a concern on organic farms that use poultry manure as a primary crop nutrient source, and that erosion and runoff loss of P may be of concern on organic farms producing annual crops because more tillage is required for weed control. Whole-farm budgets with prices that reflect recent conditions showed an economic advantage for organic over conventional production. A sensitivity analysis showed that this economic advantage depended on a higher milk price for producers of organic milk and was influenced by the difference in milk production maintained by herds using organic and conventional systems. Factors found to have little effect on the relative profitability of organic over conventional production included the differences between organic and conventional prices for seed, chemicals, forage, and animals and the overall costs or prices assumed for organic certification, machinery, pasture fencing, fuel, and labor. Thus, at the current organic milk price, relative to other prices, the case study organic production systems seem to provide an option for improving the economic viability of dairy operations of the scale considered in Pennsylvania. To motivate transition to organic systems, the economic advantage found requires the persistence of a substantial difference between conventional and organic raw milk prices.