• Journal of Environmental Health Sciences
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• v.31 no.1
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• pp.55-60
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• 2005

The occurrence and abundance of protozoa at advanced wastewater treatment plant were compared with operating parameters and effluent quality using statistical procedures. In correlation analysis between the distribution of protozoa and operating parameters, the distribution of protozoa was showed the operating condition of plant. Regression analysis between the distribution of protozoa and effluent quality up to 7 days, showed the R-square values of most regression equation were more than 0.6 and constant was higher than slope and could indicate effluent quality from sampling day to 7 days. Once enough data concerning protozoa, operating parameters and effluent has been gathered, the operator has a valuable tool for predicting plant performance and near-future effluent quality based on microscopic examination. Plant operator manipulates operating conditions if he knows near-future data of effluent is deteriorating. Perhaps more importantly it can be used to actually control the plant to adjust the operating conditions to obtain the protozoal populations that have been shown to provide the best effluent quality.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.471-476
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• 2007

Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}C$ annually and the quality of that water is as good as living water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effuent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and c lose type heat pump system using effluent ground water was installed and tested for it church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000$ ton/day. The heat pump capacity is 5RT each. The heat pump cooling COP is $4.9{\sim}5.2$ for the open type and $4.9{\sim}5.7$ for close type system. The system cooling COP is $3.2{\sim}4.5$ for open type and $3.8{\sim}4.2$for close type system. This performance is up to that of BHE type ground source heat pump.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.87-90
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• 2001

The volatile flavor components of snow crabs from the Young-duk coast of Korea and their concentrated cooker effluent were isolated by a modified method from Likens and Nickerson, using a simultaneous distillation and extraction apparatus. The concentrated extract was analyzed and identified by gas chromatography and GC-MS. The flavor profile of boiled crab demonstrated that the favorable flavor characteristic of crab involved a seafood-like note, and that of concentrated cooker effluent demonstrated that the weak boiled crab flavor involved a fishy note. The main flavor components of boiled crab were heterocyclic compounds including alkylpyrazines, thizoles and thiolanes, aliphatic ketones including 2-heptanone and nonanone. On the other hand, the main flavor components of cooker effluent were aldehydes including 3-methylbutanal, alipatic ketones including 2-heptanone and alkanes including 2,6,10,14-tetramethyl-pentadecane. Almost all of heterocyclic compounds, which seem to be important contributors to the flavor of boiled crab, were not identified in concentrated cooker effluent. As a result, there may be a need to add the crab flavor components formed through model experiments of Maillard reactions to the concentrated cooker effluent for human consumption.

• Journal of Korean Society on Water Environment
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• v.23 no.1
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• pp.12-18
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• 2007

Difference of total coliforms (TC) survival time of mixed samples (effluent were mixed by seawater or freshwater) were examined in various conditions. The time taken to achieve a 90% reduction in the TC concentration ($T_{90}$) of effluent, high initial TC concentration and low initial TC concentration samples indicated 143.9, 121.9 and 89.6 hours at $25^{\circ}C$, respectively. At $4^{\circ}C$, log removal rate after 336 hours were 0.96, 1.04, and 1.30. TC survival time of effluent-inoculated seawater sample was longer than that of effluent-inoculated freshwater sample in laboratory. At outdoor condition, TC inactivation curves of effluent-inoculated seawater or freshwater samples showed similar patterns. And both of them were greatly influenced by climate condition. There was not enough evidence that TC survived longer in freshwater than sea water. It was unlikely that the salinity of sea water contributed to the inactivation process of TC.

• New & Renewable Energy
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• v.3 no.2 s.10
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• pp.40-46
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• 2007

Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}...$ annually and the quality of that water is as good as well water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effuent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and close type heat pump system using effluent ground water was installed and tested for a church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000\;ton/day$. The heat pump capacity is 5RT. The heat pump heating COP was $3.85{\sim}4.68$ for the open type and $3.82{\sim}4.69$ for the close type system. The system heating COP including pump power is $3.0{\sim}3.32$ for the open type and $3.32{\sim}3.84$ for close type system. This performance is up to that of BHE type ground source heat pump.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.275-280
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• 2004

This study was performed to investigate the disinfection efficiency and the formation characteristics of disinfection by-products(DBPs) by chlorination in the sewage effluent. The effluent was sampled from the sewage treatment plants operated in the activated sludge process and the advanced sewage process. The type of DBPs investigated were Trihalomethanes(THMs), Dichloroacetonitrile(DCAN), Chloral hydrate(CH), Dichloroacetic acid(DCAA), Trichloroacetic acid(TCAA). Major findings are as follows. First, the optimum injection concentration for chlorination in sewage effluent were found to be in the range $0.5{\sim}1.0mg\;cl_2/L$. Also, It was found that the chlorine dosage in the effluent of activated sludge process was higher than in the effluent of advanced sewage process. Second, the maximum formation concentration of THMs were $12.7{\mu}g/L$. The THMs formation reaction was finished in a short time of several seconds and chloroform was mainly formed. Also, it was found that the concentration of ammonium nitrogen is higher, the concentration of THMs is lower. Third, it was found that DCAA and TCAA were mainly formed as DBPs by disinfection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.954-959
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• 2022

Marine outfalls are used to discharge treated liquid effluents to the environment. An efficiently designed, constructed and operated marine outfall effectively dilutes the discharged effluent, thereby reducing the risk to biota and humans dependent upon the marine environment. In this study, we investigated the effluent transport from a marine outfall at different depths in Masan Bay. A particle-tracking model was used to predict the dispersion of effluent. The model results indicate that some particles released from a depth of 13 m move to the inner area of Masan Bay within 48 h. As the release depth increases after 48 h, the particles move further southward. This suggests that effluent from the outer area of Masan Bay can affect the inner area, and that this effect can be reduced by increasing the depth of effluent release.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1168-1176
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• 2004

Intensive animal industries create large volumes of nutrient rich effluent, which, if untreated, has the potential for substantial environmental degradation. Aquatic plants in aerobic lagoon systems have the potential to achieve inexpensive and efficient remediation of effluent, and to recover valuable nutrients that would otherwise be lost. Members of the family Lemnaceae (duckweeds) are widely used in lagoon systems, but despite their widespread use in the cleansing of sewage, only limited research has been conducted into their growth in highly eutrophic media, and little has been done to systematically distinguish between different types of media. This study examined the growth characteristics of duckweed in abattoir effluent, and explored possible ways of ameliorating the inhibitory factors to growth on this medium. A series of pot trials was conducted to test the tolerance of duckweed to abattoir effluent partially remediated by a sojourn in anaerobic fermentation ponds, both in its unmodified form, and after the addition of acid to manipulate pH, and the addition of bentonite. Unmodified abattoir effluent was highly toxic to duckweed, although duckweed remained viable and grew sub optimally in media with total ammonia nitrogen (TAN) concentrations of up to 100 mg/l. Duckweed also grew vigorously in effluent diluted 1:4 v/v, containing 56 mg TAN/L and also modified by addition of acid to decrease pH to 7 and by adding bentonite (0.5%).

• Journal of Korean Society on Water Environment
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• v.33 no.2
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• pp.197-202
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• 2017

This paper aimed to evaluate the test results of acute toxicity on effluent samples which were exempted from applying of ecotoxicity criteria. Total 316 effluent samples which were free from controlling of ecotoxicity regulation, were tested. Ratio of effluent samples which were exceeded the ecotoxicity criteria (TU > 1) indicated 23.7%. This ratio was a little bit higher than previous study (22.7%) on effluent samples which were controlled under ecotoxicity criteria. These results mean that our ecotoxicity management system is not appropriate and applying of ecotoxicity criteria to all effluent samples (82 industry categories) were needed in order to improve our ecotoxicity system. In addition, the same numeric criteria (TU 1 or 2) for all industry categories were proposed in consideration of these results. Ratio of effluent samples which exceeded the ecotoxicity criteria (TU > 1) with D. magna indicated 23.7%. However V. fischeri showed 14.6%. As a acute toxicity test organism, D. magna seemed to be more sensitive than V. fischeri. Ratio of samples which were exceeded TU 1 with D. magna by 24 h exposure period test indicated 35 %, whereas 48 h showed 41%.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.471-478
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• 2012

The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, 'potential water retention capacity' (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer's grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (${\pm}10.3$). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship.