With this publication we would like to introduce the field of “Biodegradability of organic substances in waters and treatment plants” to our partners in the chemical and other branches of industry.

Using

N-Methylpyrrolidone (N M P)

as an example, the general principles of wastewater treatment as well as related chemical and biological terms are explained in a basic way.This paper should assist the reader in drawing his own conclusions from laboratory tests and in assessing the applicability of such tests to commercial scale operations.

Furthermore, it was our objec- tive to complement the very positive data published on NMP, so far, with an external study done by the University of Stuttgart. The data developed by the University, their evaluation and interpretation, may show new ways especially to those industries seeking environmen- tally safer alternative solvents.

The information submitted is based on our present technical knowledge and experience. This publication has been compiled to the best of our knowledge. It does, however, not claim to be complete and does not relieve readers from the responsibility of conducting their own tests and of conforming to any prop- erty rights, existing laws, and regulations. In view of the many factors that may affect under- standing and application, the data contained in this publica- tion do not imply any legally binding warranty or assurance of certain properties or of suit- ability for specific purpose. Any responsibility of BASF in con- nection with the information and data contained herein is expressly excluded.

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Content

1.

2.

3.

4. 4.1 4.1.1 4.2 4.2.1

4.2.2 4.2.2.1 4.2.2.2 4.3

Chemical Nature 4

Applications 5 ~

‘ Key Data 6

Biological Degradation Processes 7 -

Introduction 7 Wastewater Treatment Plant Operation 8 Measures of Biodegradability and Test Procedures 9

Theoretical Oxygen Demand 10 Total- and Dissolved Organic Carbon Batch test according to Zahn-Wellens

Biochemical-, Chemical- and

12 12

Ecotoxici ty 13 Coupled-Units-Test (Dynamic Degradation Test) 12

5. Biodegradability of NMP 14

6. Biodegradability Study of NMP in Domestic Sewage 16

6.1 Introduction 16 6.2 Test procedure and results 16 6.3 Summary 19

7. BASF’s Consultants on Wastewater Engineering 20

8. BASF’s Guidelines for Environmental Protection and Safety 21

9. Institute for Water and Wastewater, Engineering, and Waste Handling of the University of Stuttgart 22

10. References 24

1 t. Index 26 .

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Chemical Nature

IJ \

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l-Methyl-2-pyrrolidinone

Formula C,H,NO Molecular Weight 99.13 g/mol

CAS NO. 872-50-4

Applications

N-Methylpyrrolidone (NMP) is a slow evaporating solvent with low viscosity. Its excellent solvent power as well as its favorable ecologi- cal and toxicological properties have been the reason for the wide use of NMP within the chemical industry.

Due to health and safety, toxicological, and environmental pressures during the 1980’s’ restrictions have grown in the use of certain solvents.This has led to an even wider use of NMP in existing market segments as well as the introduction of NMP into new areas:

0 Formulation of plant protection products;

0 Coating- and paint professionals value its high solvent power when removing cured and non-cured coats;

0 Its unique property, to dissolve carbon deposits, are utilized when engines and generators need to be overhauled.

The above examples can only give a brief idea about the potential of NMf? More detailed information about the various applications, physical properties as well as data on storage, handling, and toxi- city can be found in the respective NMP-Product brochures. [I, 21

Key Data

The following data were obtained from BASF measurements or derived from literature:

Physical Data

Boilins Point 204.3 "C Density d,, (DIN 51 757) 1.028 g/ml Vapor Pressure (at 20 "C) 0.32 mbar Refractive Index nZ5 1.469

91 "C Ignition Temperature (DIN 51 794) 245OC

Ecological Data

BOD, (DIN 38 409, Part 51) 1 100 mg/ml COD (DIN 38 409, Part 41) 1600 mg/ml TOC (DIN 38 409, Part 3) 600 mg/ml Biodegradability (DIN 38 412, Part 25; Zahn-Wellens static test)

Flash Point (DIN 51 758)

> 90 % DOC-degradation (soluble organic carbon degradation)

Ecotoxicity

Golden orf (Leuciscus idus) > 4600 mg/l EC,,, 48h (DIN 38 412) < 10 000 mg/l Rainbow trout (Oncorhynchus mykiss) EC50, 96h > 500 mg/l Water flea (Daphnia magna Straus) EC50, 24h (DIN 38412/11) > 1000mg/l Algae (Scenedesmus subspicatus) EC,,, 72h (DIN 38 412/9) > 500 mg/l Bacteria (Pseudomonas putida) EC,,, 48h (DIN 38412/8) > 9000 mg/l

For sales specifications and safety data please refer to our current Data Sheet 112 and Safety Data Sheet.

. _ _

Biological Degradation Processes

4.1 Introduction

Acute Toxicity

Chronic Toxicity

Eutrophication

Bioaccumulation

Biodegradation refers to the biological (usually by bacteria) caused elimination of organic substances. Microorganisms employed in degradation processes need to adapt (acclimate) their metabolism to chemicals, which are discharged into a treatment plant for the first time (or after a longer absence). When oxygen is present, the process is termed aerobic biodegradation and the end products are carbon dioxide and water. In practice, complete oxidation is rare. More commonly, a partial breakdown occurs resulting in the forma- tion of CO,, H,O, and metabolites. The conversion of organic material into anorganic compounds, like NH,, CO,, H,O is called mineralization.

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Most chemicals will cause environmental damage if released untreated and in sufficient quantities.The damage can take many forms depending on the product involved:

Poisoning of aquatic species by short exposure to a substance;

Poisoning of such organisms over a longer period;

The increase of nutrients in water, producing an environment that favors the growth of algae. During the mineralization of dead algae oxygen is consumed by the organisms (bacteria) involved.This con- sumption of oxygen can result in a deficiency of oxygen especially on the ground level affecting other forms of life in water, for exam- ple fish;

Accumulation of substances on individual levels of the food chain. This may (but does not necessarily have to) lead to poisoning effects.

Proper treatment of chemicals prior to their release will avoid such effects. In turn, this makes the need for means of predicting the degree of treatment evident. Considering the wide range of circum- stances that could be applicable, the type of measurements needed to make these predictions is far from being obvious.

Biodegradability is not an absolute intrinsic property. Its value and the method involved in determining that value, is dependent on the conditions which have necessitated the treatment. The same applies to the selection of tested parameters and test methods.

4.1.1 Wastewater Treatment Plant Operation

\

An example:

When assessing the risk from an inadvertently released effluent or the risk from introducing a product constantty to a wastewater, different aspects become relevant.

A toxic substance, which is easily biodegradable, may be a lesser problem to environment than a compound, which is not biodegradable at all. A product which is biodegradable, does in general also not carry the risk of bioaccumulation or long-term effects as this is the case with non biodegradable chemicals.

Consequently, the levels of treatment required and the ultimate efficiency of treatment achieved would differ as would the tests required to measure them.

A typical plant uses bacteria (technical term: activated sludge) to treat wastewater aerobically. The efficiency of treatment is for example determined by contact time, nutrition levels, method of operation, and environmental factors (pH, 0,-level, mixing, etc.). Waste removal mechanisms in a treatment plant include biodegra- dation, adsorption on the biomass and subsequent elimination during excess solids removal, and volatilization due to air stripping. It is imDortant to recognize and account for the different factors

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and mechanisms during biodegradability studies. -

Separation Combustion drying

Wastewater treatment plant operation

4.2 Measures of Biodegradability and Test Procedures

Any chemical entering a treatment plant can be categorized as either toxic, refractory (indifferent, persistent), or biodegradable. A toxic substance inhibits the biodegradation process. Lowered removal efficiencies are the result. Refractory products have no effect and are themselves unaffected. They pass as “non-biodegrad- able” the treatment ptant. Biodegradable chemicals act as a food source for the bacteria.They are broken down, serve as energy source, and support the growth of the biomass.

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In reality, the distinction between toxic, refractory, and biodegrad- able are not always clear. For instance, a given chemical may be toxic at high - and biodegradable at low concentration.

Another important factor in treatment plant performance is the degree of adaptation which has occurred. Upon prolonged exposure to a given chemical or mixture, the bacteria population will adapt to most efficiently utilize the food source. This is mani- fested as a gradual rise in removal efficiency. The adaptation may involve shifts in the relative proportions of bacterial species, genetic adaptation, or changes in the metabolic pathways. Concentration is a key factor in this process. Ifthe chemical of i‘nterest is present at a low concentration, it may be ignored in favor of more readily degradable food. Long-term exposure alone does not necessarily guarantee adaptation.

If the wastewater treatment plant is overloaded (shock load) it is possible, that the respective chemical is passing the treat- ment plant without biodegradation - it can be detected in the runoff.The same may happen, if a compound is not contained in a sewage for a longer period. However, in the runoff of any waste- water treatment plant, small amounts of some (even. biodegradable) substances can always be detected. The reason for this is that treat- ment plants operate in a stationary state like continuously running reactors.

Biodegradability is a function of the type and amgunt of bacteria available, the structure of the chemical being treated, the contact time, and various environmental factors (oxygen, pH, tempera- ture, etc.). Different treatment situations will involve different combinations of the above. Thus, it is understandable that many different types 07 tests exist.

Primary biodegradabilhy was an early test method established to measure the loss of a particular property of interest (surface tension or foaming). This test used high concentrations of adapted bacteria. Contact times were in the order of one day.

4.2.1 Biochemical-, Chemical- and Theoretical Oxygen Demand

Since only a small structural change is required in the test chemical to cause a loss of physical property, this type of test generally gives

make-up of the chemical remains unaffected. Additionally, more extensive molecular degradation would not be reflected in the measured results; for that reason, this type of test has fallen out of use.

very extensive biodegradability even though most of the molecular ~~

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Important elements in defining biodegradability are among others:

0 BOD Biochemical Oxygen Demand 0 ThOD Theoretical Oxygen Demand 0 COD Chemical Oxygen Demand 0 TOC Total Organic Carbon 0 DOC Dissolved Organic Carbon

The above parameters offer, each other complementary, information about the organic load of sewage. They are not interchangeable. Yet by combining appropriately the findings from BOD-, COD- and TOC-tests, one can draw meaningful conclusions.

According to the OECD-Guidelines [7] the following “pass levels” of biodegradation, obtained within 28 days, may be regarded as good evidence of being “readily biodegradable”: 60 Yo of BOD, 70 % of DOC.

If the BOD, is greater than 60 Yo of the ThOD or COD, the sam- ple is also classified as “readily biodegradable”.

The methods for determining the above parameters have, for example, been documented in DIN-Sheets, EEC- or OECD-Guide- lines, and American publications on test methods [3 - 61.

The BOD is an example of a respirometric (oxygen consuming) determination of biodegradability. By measuring oxygen consump- tion, this test provides a better indication of the extent of degrada- tion of the chemical structure than does loss of a pr0perty.Thi.s type of test is generally run with low concentrations of bacteria, which may or may not be adapted to a chemical, with contact times in the order of 1 - 5 days. The length of test is designated by subscript with the common 5 day test being termed BOD,; the units are typically calculated as O,/g chemical.

Closed Bottle Test

BOD

COD

Another type of test takes the respirometric test a step further by increasing the contact time to 30 days or longer (virtually ensuring that the bacteria are adapted). The objective of this test is to measure the ultimate biodegradability, i. e. the greatest possible extent of degradation.This testing simulates the environmental fate of chemicals in a receiving water. The biode- gradability values are usually higher than those from shorter-term BOD tests.

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The Closed Bottle Test is essentially a 28 day BOD. Intermediate values are determined at 5,15, and 28 days.Thus, a profile of BOD vs. time is established.

BOD is often reported as a percentage of theoretically complete oxidation (ThOD). These biodegradability values are generally lower than those reflecting the loss of a property even though the extent of treatment may often be greater.

Another reference used is the Chemical Oxygen Demand (COD). The COD measures (for practical purposes) the complete oxidation of a chemical to CO, and H,O. The biodegradability determined by COD reduction is usually lower than values received from any other test.

When interpreting BOD values, one has to be aware of the following, unfavorable conditions:

0 Small quantity of bacteria- and test substance 0 No agitation during incubation 0 Limited supply of oxygen 0 In the case of the BOD, a relative short test time.

Still - if the result is positive, one can assume, that the test good is also easily biodegradable in the waters or treatment plants. A low BOD,-value combined with a high COD-value would require further biodegradation tests.

4.2.2 Total - and Dissolved Organic Carbon

The Total Organic Carbon (TOC) is used to describe a molecule or a waste sample. Values of biodegradability obtained by monitoring this parameter generally lie between BOD- and COD-values.

An important parameter for degradation tests is the dissolved organic carbon (DOC). If for example more than 90 % of the DOC have been eliminated, it can be concluded, that all organic compo- nents (original substances and their metabolisms) have been removed. Contrary to this, the elimination of one specific substance would not allow such a conclusion. It is possible, that it only has been transformed into other organic intermediates (metabolites), which are still present in the wastewater. Compared to the original products, their metabolites can show a different pattern in degrada- tion and effects on environment.

4.2.2.1 Batch test according The Zahn-Wellens-Test measures over a period of 28 days the removal of DOC.The test system is fed once at the start of the test. Samples are taken periodically.The removal of DOC is shown in a profile as percentage of the initial concentration.

The degree of elimination after 28 days and the path of the elimina- tion curve are important factors for the interpretation of the results.

A method comparable with Zahn-Wellens is the Modified-OECD- Screening-Test, which basically analyses the degree of biochemi- cal oxidation. Contrary to the Zahn-Wellens-Test it uses, however, substantially lower test good- and bacteria concentrations.

The Zahn-Wellens-Test is suitable to evaluate the potential (“inherent”) biodegradability of a substance. Many experts use it as a standard test, since in gives good indications for the biode- gradability in the actual environment of a treatment plant or water. Test good which is not biodegradable in the Zahn-Wellens batch test, is likely to be hard to eliminate in any environment. In such case it can be expected, that other tests produce similar results.

The Coupled-Units-Test simulates as a continuous, dynamic test the conditions of a wastewater treatment plant, using activated sludge. This test represents a modified version of the OECD-Con- firmatory-Tests for the determination of degradation of detergents. Compared with other degradation tests this is a fairly extensive one.

to Zahn-Wellens

4.2.2.2 Coupled-Units-Test (Dynamic Degradation Test)

Two identical pilot plants for wastewater treatment are required which are seeded with the same activated sludge. One unit serves as control, using synthetic wastewater i. e. a substrate made for example from peptone, meat extract, urea, and nutrient salts. A second unit, which also contains the above substrate, is fed over a period of 4 to 12 weeks with the test-substance.

The differences between inflow- and runoff DOC-data of both pilot plants are plotted as elimination curve. The interpretation of that curve allows conclusions about the biological degradation.

By simulating the operation of a treatment plant, the Coupled- Units-Test goes far beyond the scope of most other tests. However, while real sewage assembles a broad range of COMpOUndS in vary- ing concentrations, the inflow for the Coupled-Units-Test consists of a synthetic and standardized substrate. Another difference lies in the medium contact time of the sewage in the treatment plant, which may be different from the durations under test conditions. The process of seeding has to be standardized too. (In reality, with the sewage, new bacteria are continuously brought in).

The Coupled-Units-Test provides only limited information which could be directly transferred to a real operation. But the chances are good, that positive test results will be reproducible in municipal sewage treatment plant.

The harmful effect of chemicals released to surface water depends on its concentration in that water. All chemicals are toxic if their con- centration is high enough. It is therefore necessary to determine that concentration which just falls short of causing an effect (NOEC, No Observed Effect Concentration). Most of the tests use various forms of aquatic life as indicators of toxicity. The values reported usually show the chemical concentration at which 50 % of the respective test organisms would presumably be affected. The term for this Effective Concentration is the ECSo.

Because the life forms used vary greatly in their sensitivity to chemi- cals, the test results also vary greatly.

It is therefore essential that conclusions are only based on data, which have been developed in accordance with the respective EEC-Directives or OECD-Guidelines [4 - 51. If the EC,,-value from the fish-, daphnia-, and algae-test are above 100 mg/l, one can generally assume, that the product is not dangerous for the environment.

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4.3 Ecotoxicity

Biodegradability of NMP

River-die-away tests were conducted by Chow & Ng [8]. These tests simulate the fate of a compound in a receiving water.

Using an initial concentration of 100 ppm NMP, they found 95 % removal as measured by specific compound analysis and 45 % removal as measured by COD.

These determinations were conducted after two weeks exposure. The low GOD removal compared to the specific compound removal indicates a high degree of molecular modification (probably nitro- gen-carbonyl bond splitting) and lesser amount of mineralization. Thus, while the compound was no longer present as NMP, the compound was still present as modified fragments.

.

An additional test by the same researchers using a semi-continu- ous sludge system acclimated-for five days showed 7 day biode- gradability of 95 Yo by specific analysis. .

In similar tests, Matsui [9] used a semi-continuous system to meas- ure TOC, COD, and specific compound (by GC analysis) removal. Starting with concentrations ranging from 92 to 200 ppm NMP all results showed more than 92 % removal within 24 hours (regard- less ot the parameter being measured).

Rowe and Tullos [IO] studied biodegradability of NMP in acclimated and unacclimated sludge, static and continuous flow in a laboratory test unit. The studies were done with 300 and 1000 ppm of NMf? The continuous cells had an 18 hour hydraulic residence time. The results indicate that NMP was largely degraded (more than 98% destruction with 90 %I TOC reduction- in the continuous cells), and that significant acclimation is easily achieved (more than 75 %TOC reduction in 24 hours in static tests).

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Gerike and Fischer [ll] tested the biodegradability of 44 organic substances, including NMP, using various test methods. All test results show that NMP is virtually fully biodegradable:

M IT1 95

OECD-Screenina 99

Zahn and Wellens [I21 tested the biodegradability of 50 organic sub- stances. NMP degraded by > 90 % COD, starting with 1000 mg/l COD and a adaptation phase of 3.5 days for non-acclimated acti- vated sludge.

All results demonstrate a virtually complete biodegradation of NMP as well as of the corresponding TOC (DOC) and COD.

Biodegradability Study of NMP in Domestic Sewage

6.1 Introduction The results introduced so far have been developed using estab- lished standard tests. However, discussions with users and public

The biodegradability of NMP in a common, municipal sewage treat- ment plant (Public -Owned Treatment Works - POW). This aspect has gained importance, since NMP can be regarded as a less harmful product to environment. Because of this, NMP has become an important alternative to halogenated solvents or aromatics. N M P is growing into new application segments - for example metal cleaning or degreasing. Biodegradability studies in BASF’s own treatment plant would therefore be of limited use to such markets since their users have no access to treatment plants adapted to industrial chemicals. The study conducted by the University of Stuttgart was intended to simulate as closely as possible the con- ditions in a POTW.

authorities made it obvious, that there was one gap still to be filled: ~~ ~

6.2 Test procedure and results

The study was conducted in continuously fed bioreactors with typical POTW parameters (laboratory activated sludge plant, operated with domestic sewage). The NMP concentrations in the domestic sewage feed was set to 5 and 25 mg/l for standard opera- tion and to 40 and 500 mg/l for shock loads. With the shock load, a sudden leakage or accident should be simulated.

The above NMP-concentrations relate to a community of 10 000 people based on a corresponding dilution factor to approximately:

500 mg/l 1 000 kg/day

For a community of 50 000 people the relation is approximately:

500 mg/i 5 000 kg/day

A Storage B Feeder C Aeration D Sedimentation E Sludge Recycling F Runoff G Aerator H Flow Meter

L tab-scale pilot plant for the biological treatment of sewage through the activated sludge process

The plant consisted of a storage container for the mechanically treated sewage A, the feeder (metering pump) B, the aeration tank C (volume 5.5 I ) , the sedimentation tank D (volume 2.5 I), an air lift . pump for recycling of the settled, activated sludge E and a con- tainer F for the runoff.

The feeder B ensured a'continuous flow of sewage into the aeration tank C.

For the diffused aeration a small porous plate G was placed in the conic part of the aeration tank.The quantity of injected air was Con- trolled by a flow meter (Rotameter) H.

The tests were conducted in a pilot plant using a typical sludge of 0.3 kg BOD,/(kg TS - d) for standard operation.The NMP-concentra- tion of 500 mg/l which had been established to simulate an emer- gency situation, represents for many products an overload of the treatment plant.

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In two units normal operation was simulated with 5 and 25 m1/1 NMF! Another unit -without NMP - served as a control.

NMP was added in intervals to reflect fluctuating loads as they also happen in the every day operation of a treatment plant. This was accomplished by feeding NMP during a 24 hour cycle for 17 hours only. During the remaining 7 hours, the supply of test material was suspended (simulating night operation of a POW).

Both operations - under normal and shock load -were simulated over a period of 10 weeks.

With NMP-concentrations of 5 and 25 mg/l, the complete etimina- tion of NMP could be observed.

The higher concentration of 25 mg/l required an adaptation phase of about 3 days -with a 50 % degradation on the first day.

During the seventh week the concentration in 5 mg/l unit was raised from 5 to 40 mg/l. The other unit was increased from 25 to 40 mg/l during the third and seventh week. In both cases no signifi- cant N MP-concentrations could be detected in the effluent.

During the eighth week, the original 25 mg/l unit was not supplied with NMP. After resuming to feed 25 mg/l in the ninth week, NMP was again completely eliminated. The interruption of one week had obviously not caused deadaptation.

The original 5 mg/l unit and the control unit were supplied during the ninth week with 500 mg/l in domestic sewage. This was more than fivefold the previous total organic load. Despite such an over- load, on the first day 50 % of the NMP was eliminated.The control unit, which had not come in contact with NMP before, reached a full elimination of NMP on the fourth day while the 5 mg/l unit was almost back to normal (> 95 % elimination) on the second day. After this simulation of an accident both units operated normal.

Evaporation tests conducted in parallel confirmed that the elimina- tion of NMP can not be attributed to air stripping.

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During the 10 weeks study, no cumulative adsorption of NMP could be observed. It can therefore be concluded, that the elimination of NMP was caused by biological degradation.

6.3 Summary The following conclusions can be drawn:

0 A municipal sewage treatment plant ( P O W has a base capacity to eliminate spontaneously up to 10 mg/l without adaptation.

0 The adaptation to higher NMP-concentrations is very fast.

0 No deadaptation occurs if the supply of NMP is interrupted for one week.

0 If a P O W is not overloaded, virtually complete elimination of NMP in domestic sewage can be expected.

-

NMP is non-toxic to most aquatic life and can be readily degraded by typical wastewater treatment plant organisms.

BASF’s Consultants on Wastewater Engineering

BASF possesses extensive facilities to conduct biodegradabil- ity tests. In addition, BASF supports biodegradation research at universities throughout the world.

At the BASF sites in Ludwigshafen, Germany and in Wyandotte, Michigan USA all manner of biodegradation tests are con- ducted, ranging from simple BOD’S to complete laboratory simulation of full scale treatment plants.

The treatment plants of BASF, used to purify the waste streams from its own production, offer additional options for testing and research.

Processes which are simulated in Ludwigshafen employ regular-, fixed-bed-, and fluid-bed reactors for the following type of biologi- cal treatment:

0 Aerobic 0 Anaerobic 0 Nitrification 0 Denitrification

These technologies are complemented by mechanical, chemical, and physical methods:

0 Treatment with activated carbon 0 UV-Treatment 0 Precipitation, flocculation 0 Sludge filtration 0 Sand filtration 0 Distillation 0 Extraction

Air stripping 0 Ozone-treatment 0 H,O,-treatment 0 Membrane-treatment

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BASF’s Guidelines for Environmental Protection and Safety

BASF considers environmental protection and industrial safety an ongoing challenge basic to its work.The company applies the following guidelines: ~

Not to give economic considerations precedence over environ- mental protection and safety

To manufacture products that can be made, used, and disposed of safely; to pay careful attention to plant and employee safety

To minimize any adverse impact of production, warehousing, transportation, distribution, and product use on Man and the Environment

To take the initiative in doing what is necessary, even where no legal or regulatory mandate exists

To monitor its plants, products, emissions, and waste manage- ment on its own initiative

To further scientific and technical progress in environmental protection and product safety as an important goal

To promote environmental and safety awareness among all em p I oyees

To support customers in their safe and environmentally com- patible processing of its products with information on proper product hand I i ng

To promulgate knowledge about environmental protection and product safety through open dialogue with the public; to exchange knowledge and experience with authorities, trade and governmental associations, policy makers, and the scientific community

Institute for Water and Wastewater, Engineering, and Waste Handling of the University of Stuttgart

The Institute in connection with the Research Wastewater Treatment Plant (Lehr- und Forschungsklarwerk der Universitat Stuttgart) has a staff of about 180 employees, who work almost exclusively in the field of education and research in environmental protection technologies.

Its activities are mainly financed through public funds. In addition industry or semi- private organizations sponsor projects.

Mostly civil engineers after 3 years of undergraduate Studies are educated in drinking- and wastewater engineering/treatment, water- quality management, and waste handling.

Departments of the Institute

0 Domestic Wastewater Treatment 0 Industrial Wastewater Treatment 0 Drinking Water Treatment 0 Domestic and Industrial Refuse Handling 0 Biological Exhaust Gas Purification 0 Water Chemistry 0 Biology 0 Research WastewaterTreatment Plant

. Educational- and Research activities

Wastewater

0 Consulting, process development, and design of wastewater treatment plants for

0 Nitrification, denitrification, and phosphorus elimination 0 Removal of biological persistent substances like for example

chlorinated organic carbon compounds 0 Recycling of biologically treated wastewater for re-use by the

industry

Drinking Water

0 Prevention of microbial contamination of filters and ionic exchange units

0 Biological elimination of nitrate and chlorinated organic carbon compounds by means of microorganisms growing on bio- degradable pellets .~

0 Groundwater recovery and sanitation

Refuse

0 Development of concepts for domestic and industrial refuse disposal (separation, recovery, recycling)

0 Recovery and sanitation of existing landfill sites 0 Examination of the biodegradability of daily life good made of

biopolymers

Air

0 Chemical and olfactometric characterization (emission and immission) of exhaust air

0 Biological exhaust gas treatment with bio filters, bio washers, and membrane reactors

Analytics and biological tests

0 Basic development of new measuring and control devices 0 Determination of all parameters relevant for biodegradation 0 Survey and safeguard of analytical quality standards in public

and private laboratories

Research Wastewater Treatment Plant

0 A conventional biological wastewater treatment plant with units for tertiary and advanced treatment is operated with the objec- tive to test new measuring and control devices, as well as new treatment units under practical conditions in a technical scale

Public Relations

0 Periodic workshops and colloquiums on the fields described above; as a platform for training as well as for exchange of the latest developments in research and practice

0 Training of plant operators has been a long and successful tradi- tion at the institute in connection with the German Association of Wastewater Technique

0 Two periodicals are issued: Stuttgarter Berichte zur Siedlungswasserwirtschaft Stuttgarter Berichte zur Abfallwirtschaft

0 Consulting within Germany and abroad

References

c

7 N-Methylpyrrolidone, Product Brochure BASF Aktiengesellschaft, Ludwigshafen, CZ 3307 (1990)

2 N-Methylpyrrolidone, Handling and Storage BASF Corp., ParsippanyAJSA (1990)

3 DIN 4045

DIN 38402 -38414 DIN 38409, Part 3 DIN 38409, Part 22 DIN 38409, Part 41 DIN 38409, Part 51 DIN 3841 2, Part 8 DIN 3841 2, Part 9 DIN 3841 2, Parts 11,30 DIN 3841 2, Parts 15, 20,31 DIN 3841 2, Part 25

Definition of technical terms of wastewater engineering Testmethods Determination of TOC Determination of DOG Determination of COD Determination of BOD, Effect on Pseudomonas Effect on algae Effect on Daphnia Effect on fish Zah n -We1 I e n s -Test

4 Legislation of the European Economic Community Directive 67/548 EC including Adaptions and Amendments Specification of Packaging and Labeling of Dangerous Substances Official Journal of the European Economic Community, Luxem bo u rg

5 OECD Guidelines for Testing of Chemicals 301 D Closed Bottle Test 301 E Modified Screening Test 302 A . SCAS (Semi Continuous

302 B Modified Zahn-Wellens-Test 303 A Coupled-Units-Test Organization for Economic Cooperation and Development, Paris (1 981)

Activated Sludge Test)

6 Standard Methods for the Examination of Water and Waste- water, 1 7‘h Ed., Method 521 0 American Public Health Association, Washington D.C.

7 “Deg radation/Accu m u lation” OECD Chemicals Testing Programs Expert Group Final Report, Umweltbundesamt Berlin (1979)

8 “The Biodegradation of N-Methyl-2-pyrrolidone in Water by Sewage Bacteria” S.T. Chow and T. L. Ng, Water Research, VOI 17, p. 117-118 (1983)

9 “Activated Sludge Degradability of Organic Substances in the Waste Water of Kashima Petroleum and Petrochemical Indus- trial Complex in Japan” S. Matsui,T. Murakimi, T. Sasaki, Y Hirose, and Y lguma Progress in Water Technology, Vol 7,314, p. 645 - 659 (1975)

70

11

12

“Lube Solvents No Threat to Waste Treatment” E. H. Rowe and L. F. Tullos, Jr., Hydrocarbon Processing, 59, p. 63 - 65 (October 1980)

“A Correlation Study of Biodegradability Determinations with Various Chemicals in Various Tests” I? Gerike and W. K. Fischer Ecotoxicity and Environmental Safety 3,159 (1979)

“Biodegradability in Batch-Tests, Further Experiences and New Applications” R. Zahn and H.Z. Wellens Wasser Abwasser Forschung 13,l (1980)

Other Sources:

Glossary Water and Wastewater Control Engineering 3rd Ed American Society of Civil Engineers, NY (1981)

Dictionary of Water and Sewage Engineering Elsevier Scientific Publishing, NY (1977)

Encyclopedia of Environmental Science and Technology Gordon and Breach, NY (1976)

Lexikon der Abwassertechnik W. Bischofsberger and W. Hegemann Vulkan-Verlag, Essen Germany, 4‘h Ed. (1990)

DVGW- Regelwerk Wasser Deutscher Verein des Gas- und Wasserfachs e.V. Bonn Germany (1989)

An/-Regelwerk Abwasser Abwassertechnische Vereinigung e.V. Gesellschaft zur Forderung der Abwassertechniken, St. Augustin

Umwelt und Chemie von A-Z Verband der chemischen lndustrie e.V., Frankfurt 8‘h Edition (1990)

Oko Lexikon *

Hartwig Walletschek, Jochen Graw Beck‘sche Verlagsbuchhandlung, Munchen (1988)

Index

Term Page Term Page

Acclimate 7 No observed effect

Accumulation 798 Activated Sludge 8,12 Acute Toxicity 7 Adapt at ion 7,9,19 Adsorption 8 Aerobic 7

Air Stripping 8,18 Bacteria 78,9,10

River-Die-Away Test 14 Bioaccu m u lation 798 Biochemical Oxygen Demand 10 Seeding 13

6,10 Shock load 9,18 BOD Boiling point 6 Solids removal 8

Chemical Oxygen Demand I O , 11 Theoretical Oxygen Demand 10 Chronic Toxicity 7 ThOD 10 Closed Botfle Test 11 TOC 10

COD 6, I O , 11,14 Total organic

Contact time

Coupled-Units-Test 12, Toxicity 5,6,7,13 8i Treatment plant 8,19 Deadaptation

Density Vapor Pressure 6 Dissolved organic carbon 10, 12 Zahn-Wellens-Test 12,15 DOC 6,10,12,13,15 EC60 13 Ecotoxicity 6,13 Effective concentration 13 Efficiency 8 Elimination 7, 13 Environmental Factors 8,9 Eutrophication 7 Flash Point 6 Ignition temperature 6 Indifferent 9 Inherent biodegradable 12 Metabolites 712 Microorganisms 7 Mineralization 7,14 Modified OECD Screening Test 12,15

concentration (NOEC) 13 OECD Confirmatory Test 12 Oxydat i on 711 Oxygen 79,lO Persistent 9 P O W 16 Readily biodegradable 10 Refractive Index 6 Refractory 9 Respirometric 10,11

Base capacity 19

8i l3 carbon 10, 12

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