Unit 9 - Lesson 3 - Effluent

Question 1

What is effluent?

Answer 1

A simple way to think about effluent is that it is all the water we bring into the distillery, minus the water that goes into the product and the water lost through evaporation.

Question 2

What are the main components of effluent?

Answer 2

Waste (wash and lees residues) from fermentation activities
Raw material or product residues removed from sieves or filters
CIP rinse water
Used (dirty) detergent and sanitiser
Environmental waste from general cleaning
Product waste from tank rinses

Question 3

Effluent Description - Spent or dark grains

1. Usual Disposal Route
2. Storage Container

Answer 3

1. Animal feed

2. Silo

Question 4

Effluent Description: Pot ale or lees

1. Usual Disposal Route
2. Storage Container

Answer 4

1. Animal feed, food, and pharmaceutical industry

2. Waste yeast tanks

Question 5

Effluent Description: Hazardous chemicals

1. Usual Disposal Route
2. Storage Container

Answer 5

1. Specialist waste contractors

2. Secure storage area

Question 6

Effluent Description: Waste solvents, fuel, and paint

1. Usual Disposal Route
2. Storage Container

Answer 6

1. Absorbed using spill kit then taken away by specialist waste contractors
2. Secure storage area

Question 7

Effluent Description: Wash and heads and tails

1. Usual Disposal Route
2. Storage Container

Answer 7

1. Recycled to recover extract and alcohol

2. Recycled where possibe

Question 8

Effluent Description: Spent oil and grease

1. Usual Disposal Route
2. Storage Container

Answer 8

1. Recycle

2. Bunded tank

Question 9

Effluent Description: Special cleaning chemicals

1. Usual Disposal Route
2. Storage Container

Answer 9

1. Specialised disposal

2. Bunded drum

Question 10

Effluent Description: Biohazard waste (lab/sanitary/human)

1. Usual Disposal Route
2. Storage Container

Answer 10

1. Autoclaved or specialised disposal

2. Biowaste bins

Question 11

Effluent Params - Volume

Answer 11

Volume (also called hydraulic volume):

The amount of effluent discharged within a set period.

Question 12

TSS

Answer 12

Total Suspended Solids
The amount of suspended solid material or total suspended solids (TSS) in the liquid effluent. This is important because solids are harder to treat, and often require separate treatment steps. We will explore these late

Question 13

COD

Answer 13

The chemical oxygen demand (COD) measures the theoretical amount of oxygen required to break down (oxidise) biological matter in the effluent.

Question 14

How is COD measured?

Answer 14

We can measure COD in several ways. A common test is to use a mixture of sulphuric acid and potassium dichromate to provide the oxygen. The potassium dichromate is used up in the process as it oxidises organic matter. So, measuring the amount of potassium dichromate remaining after the test will tell us how much oxygen is required.

Question 15

BOD

Answer 15

The biological oxygen demand (BOD) measures the amount of oxygen that is required by micro-organisms to digest the most readily available nutrients present in the effluent. The amount of oxygen consumed is measured over a five day period. The test is thus known as BOD 5. This value is usually lower than the COD, and the difference indicates the ease/difficulty of dig

Question 16

What is BOD 5

Answer 16

Term coined for measuring BOD over a 5 day period

Question 17

Effluent loading

Answer 17

The BOD, COD, and TSS are known collectively as the effluent loading. This basically refers to how dirty the water is, or how much treatment it will need before it can be safely discharged to a watercourse.

Question 18

Effluent pH

Answer 18

This is the measure of the acidity or alkalinity of the effluent. To be suitable for releasing into rivers, it must be close to neutral (pH 7). Furthermore, a low or high pH can damage both sewer pipes and receiving equipment, so limits must be set.

Question 19

Effluent Temperature

Answer 19

It should typically be < 20°C if it is to be released into watercourses. High temperature effluent must be blended and/or chilled to achieve a decrease in temperature. High temperatures can also crack sewer pipes, so a maximum temperature must be specified.

Question 20

How to help reduce effluent?

Answer 20

Use flow meters and auto-sampler to test for TSS, CDO, BDO

Question 21

What does difference of COD and BOD mean and which is usually lower?

Answer 21

Ease or difficulty of digestions. BOD is usually lower

Question 22

What is the test for COD?

Answer 22

Sulphuric acid and potassium dichromate to provide the oxygen

Question 23

What can in-line meters provide

Answer 23

Use in-line meters to measure pH and temperature continuously.

Question 24

What is a good practice and why for collecting effluent data?

Answer 24

Collecting last runnings from spent grains or draff, which can contain high-suspended solids and a high COD and BOD. We can reuse last runnings collected into a weak wort vessel for use in the next mash

Question 25

What is very high in BOD

Answer 25

Pot Ale So dont flush it Make into a valuable co-product, such as dark grains or pot ale syrup.

Question 26

What contributes to a high volume and temps of effluent and what to do?

Answer 26

Wort cooling water can contribute to high volumes and temperatures. We can recover and reuse it for other purposes.

Question 27

What typically happens to cleaning water and what can you do?

Answer 27

Water and chemicals for plant cleaning generally go straight to drain. They can contribute to high volume, pH and COD. However, we can recycle final rinses and its detergents.

Question 28

Effluent disposal is charged by volume. What can you do to reduce volume

Answer 28

Use CIP final rinse water as pre-rinse Limit washdown hose use (use squeegees) Use low flow, high pressure rotary CIP heads

Question 29

What is a Facultative Lagoon?

Answer 29

  Facultative lagoons resemble vast, shallow ponds, where microbes digest the BOD in the effluent. A facultative lagoon is shown in the figure below:

Question 30

What are traditional ways to treat effluent?

Answer 30

The traditional method of treating effluent was via facultative lagoons, or low-rate trickling filters.

Question 31

What is a Low-rate trickling filters

Answer 31

Low-rate trickling filters are large vessels filled with rough stones, over which the effluent trickles. Microbes on these stones digest and remove the BOD from the effluent.

Question 32

How is effluent broken down

Answer 32

Primary - pH & suspended solid - 40% removal Secondary - BOD/COD with AD and Aerobic 85-95% removal Tertiary - Combos 1&2 with ~100% removal After tertiary treatment, the water can be discharged to a watercourse or be recycled back into the distillery. Even though this water is completely safe,

Question 33

How to do Primary effluent treatment of pH

Answer 33

Balance tanks are designed to ensure that any subsequent treatment equipment receives an even flow of effluent. They hold large volumes and are generally designed to hold around 12 hours of effluent. This means that any spikes in loading and fluctuations in pH are evened out. settleable solids can be removed by gravity, sometimes use coagulants

Question 34

Another method for pH removal in the primary effluent treatment?

Answer 34

Another common method used is dissolved air flotation (DAF). In a DAF plant, millions of tiny air bubbles stick to the coagulated solids, float to the surface, and are then skimmed off. The resulting clarified and pH corrected effluent is known as the supernatant.

Question 35

What happens to the sludge in Primary treatment?

Answer 35

Dewatered either sent to landfill, incineration or fertilizer If copper is involved could pose an issue for animals

Question 36

What are two avenues for Secondary treatment?

Answer 36

Aerobic or. AD

Question 37

What does AD do

Answer 37

breaks down organic compounds, such as carbohydrates, proteins, and lipids, is achieved using anaerobic bacteria in the absence of oxygen. Benefit is BIOGAS to be used onsite

Question 38

What is An upward flow anaerobic sludge blanket (UASB)

Answer 38

A blanket of granular sludge, consisting of anaerobic microbes, is suspended in the tank. Effluent flows upwards through the blanket and is digested by these anaerobic microbes. The upward flow of effluent stops the sludge blanket from sinking to the bottom, while the settling action of gravity means that the blanket is not pushed to the top

Question 39

What is good about UASB digesters?

Answer 39

Produce robust biogas

Question 40

Most common Aerobic Secondary treatment

Answer 40

The activated sludge system is the most common type of aerobic treatment system.

Question 41

How much organic sludge results from aerobic treatment?

Answer 41

Typically, 40-80% of dissolved organic material is converted into organic sludge,

Question 42

What is the Mogden formula:

Answer 42

a way to calculate the disposal cost of effluent and byproducts Mogden formula: P = C + V + (St / Ss) S + (Ot / Os) O