Guidelines for grit sampling and characterization / Water Environment Federation.

Format:

Book

Author/Creator:

Water Environment Federation, author.

Contributor:

Water Environment Federation.

Series:

WEF special publication

Language:

English

Subjects (All):

Sewage--Sampling.

Sewage.

Sewage--Sampling--Guidebooks.

Physical Description:

1 online resource (xvii, 105 pages).

Place of Publication:

Alexandria, Virginia : Water Environment Federation, [2017]

Summary:

Guidelines for Grit Sampling and Characterization addresses the "last frontier" in liquid systems treatment by documenting and examining the methods currently in use. Driven by the industry's increasing need to determine how grit can be better characterized, modeled, and reliably removed, this book is a first step toward understanding the implications of the methods selected and allowing for proper design and optimization of grit removal systems. The book discusses methods for: characterizing grit; obtaining a grit sample, including cross-channel sampling and dry sieving, full-depth sampling and wet sieving, and primary sludge sampling; analyzing a grit sample; and using grit characterization data. The authors also identify gaps in the current knowledge and make the case for further research in critical areas.

Contents:

Intro

Title Page

Copyright

Contents

List of Figures

List of Tables

Preface

Chapter 1 Introduction

1.0 PURPOSE

1.1 Scope of the Document

1.2 Grit Testing Applications

1.3 Summary of Current Testing Methods

1.3.1 Cross-Channel Sampling and Dry Sieving

1.3.2 Full-Depth Sampling and Wet Sieving

1.3.3 Primary Sludge Sampling

1.4 Issues Associated with Lack of Performance Testing Standardization

2.0 GRIT CHARACTERISTICS

2.1 Fractionation of Solids in Wastewater

2.2 Historical Definitions

2.3 Definition for the Purpose of Sampling

2.4 Physical Characteristics of Grit

2.5 Influence of the Collection System on Grit Characteristics and Loading

2.6 Influence of Geology on Grit Characteristics

2.7 Grit Loading Patterns

2.8 Grit Distribution Versus Flow Characteristics in Channel

2.9 Roles of Interested Parties in Grit Characterization

2.9.1 Role of the Service Utility

2.9.2 Role of the Consulting Engineer

2.9.3 Role of the Grit Characterization Testing Company

2.9.4 Role of the Grit Removal Equipment Manufacturers

3.0 REFERENCES

4.0 SUGGESTED READING

Chapter 2 Sampling Practices

1.0 Site Safety Considerations

1.1 General Safety Precautions for Wastewater Sampling

1.2 Site Access to a Sample Location

1.3 Engulfment and Fall Protection

1.4 Confined Space and Toxic Gases

2.0 Grit Sampling Point

2.1 General Recommendations for Grit Sampling Points

2.1.1 Grit Profile Versus Velocity Profile

2.1.2 Sampling from Channels, Pipes, and Structures

2.1.3 Influence of Recycled Flows

2.2 Influent and Effluent of Grit Removal Equipment

2.2.1 Grit Chambers

2.2.2 Grit Classifiers, Washers, and Hydrocyclones

2.3 Grit Well (Grit Hopper, Grit Pot, Underflow)

3.0 Field Pre-Tests

3.1 Mechanical Checks

3.1.1 Screens.

3.1.2 Grit Washing and Dewatering Equipment

3.1.3 Grit Removal Equipment

3.2 Hydraulic Checks

3.2.1 Collection System Considerations

3.2.2 Velocity at Peak Diurnal Flowrate

3.2.3 Velocity at Minimum Daily Flowrate

4.0 Tested Flowrates

4.1 Average Daily Flowrate

4.2 Peak Flowrate

4.3 Maximum Possible Flowrate and Wet Weather

5.0 Grit Tested

5.1 Endemic Grit

5.2 Grit Seeding

5.2.1 Particle Size Distribution

5.2.2 Material

5.2.3 Concentration

6.0 Grit Sampling Methods and Equipment

6.1 Bucket Sampling

6.2 Single-Point Pumped Sampling

6.2.1 Single Height

6.2.2 Varying Height and Width Schedule

6.2.3 Equipment and Setup

6.2.3.1 Sample Probe

6.2.3.2 Pumps

6.2.4 Sample Collection Procedures

6.3 Multiple-Port Vertical Sampling

6.3.1 Sample Method Overview

6.3.2 Equipment and Setup

6.3.3 Sample Collection Procedures

6.4 Vertically Integrated Slotted Sampling

6.4.1 Sample Method Overview

6.4.2 Equipment and Setup

6.4.3 Sample Collection Procedures

6.4.4 Precautions

6.5 Manifold Pumped Sampling

6.6 Siphon Cross-Channel Sampling

6.6.1 Sample Method Overview

6.6.2 Equipment and Setup

6.6.3 Sample Collection Procedures

6.7 Complete Mixing of Raw Influent Channel

6.7.1 Sample Method Overview

6.7.2 Equipment and Setup

6.7.3 Sample Collection Procedures

7.0 Grit Sample Settling

7.1 Grit Settler Design

7.2 Setup and Integration with Sampling Equipment

7.2.1 Piping Configuration Between Pump and Settler

7.2.2 Fraction of Sampled Flow to Settler

7.3 Settler Operation

7.4 Sample Retrieval

8.0 Discussion and Comparison of Sampling Methods

9.0 References

Chapter 3 Characterization Practices

1.0 SAMPLE PRETREATMENT

1.1 Reduction

1.1.1 Purpose

1.1.2 Methodology.

1.1.3 Examples from Water Resource Recovery Facilities

1.2 Rinsing

1.2.1 Purpose

1.2.2 Methodology

1.2.3 Examples of Rinsing Being Critical

1.3 Coarse Wet Sieving

1.3.1 Purpose

1.3.2 Methodology

1.3.3 Sieve Analysis

2.0 SOLIDS

2.1 Total Solids (Standard Methods 2540B)

2.2 Fixed and Volatile Solids (Standard Methods 2540E and 2540G)

2.3 Settleable Solids (Standard Methods 2540F)

2.4 Density/Specific Gravity

3.0 SETTLING VELOCITY

3.1 Particle Settling Velocity

3.1.1 Type I Settling (Discrete Settling)

3.1.2 Type II Settling (Flocculent Settling)

3.2 Particle Resuspension Threshold

3.3 Measuring Settling Velocity

3.3.1 U.S. Environmental Protection Agency

3.3.2 ViCAS

3.3.3 Imhoff Cone

4.0 PARTICLE SIZE AND SHAPE ANALYSIS

4.1 Wet Sieving

4.1.1 Purpose and Location in Process

4.1.2 Methodology

4.1.2.1 Stacked Sieves

4.1.2.2 Individual Sieves

4.1.3 Considerations

4.2 Dry Sieving

4.2.1 Purpose and Location in Process

4.2.2 Methodology

4.2.2.1 Stacked Sieves

4.2.2.2 Individual Sieves

4.2.3 Considerations

4.3 Particle Shape Analyses

4.4 Particle Image

4.4.1 Methodology

4.4.1.1 Preprocessing (Setup)

4.4.1.2 Sampling

4.4.1.3 Post-Processing

4.4.2 Examples from Water Resource Recovery Facilities

5.0 CALCULATIONS

5.1 Quantity of Grit

5.1.1 Liquid Stream

5.1.2 Solids Stream

5.1.3 Relation of Concentration to Sampling Flowrate

5.1.4 Effect of Equipment on Concentration Measurement

5.2 Sand Equivalent Size

5.2.1 Relation to Settling Velocity

5.2.2 Conversion of Actual Size to Sand Equivalent Size

5.3 Removal Efficiency

5.3.1 Representative Mass Balance

5.3.2 Mass Balance Based on Concentration

4.0 REFERENCES

Chapter 4 Gaps in Knowledge and General Recommendations

1.0 OVERVIEW.

2.0 INTERNATIONAL GRIT PRACTICES

3.0 DESIGN AND OPERATIONAL EXPECTATIONS

3.1 Define Expectations

3.2 Removal Quantity

3.3 Summary of Knowledge Gaps from Chapters 2 and 3

3.4 Evaluation of Grit Characteristics

3.5 Typical Operational Issues

3.6 Identify Needs and Requirements

4.0 MODELING WITH GRIT CHARACTERIZATION

4.1 Grit Modeling

4.1.1 Static Models

4.1.2 Dynamic Models

4.1.2.1 Computational Fluid Dynamics

4.2 Computational Fluid Dynamics Model Inputs

4.3 Computational Fluid Dynamics Model Calibration

4.4 Computational Fluid Dynamics Model Validation

4.5 Computational Fluid Dynamics Simulations

4.6 Application of Computational Fluid Dynamics Modeling Results

4.7 Process Effects

4.8 Screening

4.9 Pumping

4.10 Primary Settling

4.11 Liquid Processes

4.12 Solids Process

5.0 FUTURE EXPECTATIONS

6.0 REFERENCES

Index.

Notes:

Includes bibliographical references and index.

Description based on print version record.

ISBN:

1-57278-331-1

1-5231-0531-3