Requirements for chlorination equipment, Part 4: Gravity feed type gaseous chlorinators
1983 Edition

This section defines the scope of IS 10553 Part 4, focusing on tubing used in chlorination plants. It specifies acceptable materials including phosphorus deoxidised non-arsenical copper (IS:191 Part 8-1980), phosphorus deoxidised arsenical copper (IS:191 Part 10-1980), and carbon steel (IS:1030-1974). Minimum wall thickness and tolerances are detailed according to tube diameter and material, ensuring safety and compatibility. Tables illustrate wall thickness requirements and chlorine solubility in water at various temperatures, vital for chlorination process design. Notes emphasize rounding of test values per IS:2-1960 and matching significant figures with standard requirements.

This segment describes the types of chlorinators under IS 10553 Part 4, including wall-mounted units for compact installations, pedestal-mounted standalone devices for ease of maintenance, and cylinder-mounted versions designed for portability. It highlights the necessity for precise chlorine dosing and safe handling, with vacuum feed chlorinators (covered in Part 2) being preferred for enhanced safety and control. A table on chlorine gas solubility at various temperatures aids in the design of solutionizer towers for effective chlorine dissolution.

Details regarding materials for tubes and components are provided, specifying copper types and carbon steel for tubing with defined minimum thickness and tolerance values. Metallic parts in contact with chlorine gas must be silver-plated brass, nickel, or stainless steel (the latter only for dry chlorine gas). Non-metallic components should be made from glass, ebonite, or plastics resistant to chlorine and acid. Nuts, bolts, and brackets are required to be chromium plated brass or cadmium plated mild steel. Chlorine solubility data is also included to assist in component design.

This section outlines performance expectations, emphasizing material requirements for metallic and non-metallic parts to ensure corrosion resistance and durability. It specifies that test and analysis results are to be rounded according to IS:2-1960, maintaining significant figures consistent with the standard. Chlorine solubility decreases with increasing temperature, a critical factor for dosing calculations and system efficiency. A flow diagram illustrates the typical gas flow through pressure reducing valves, moisture traps, regulating valves, and injection points to ensure compliance.

The solubility of chlorine gas in water is temperature dependent and critical for designing solutionizer towers to achieve efficient chlorination. Chlorine dosage calculations must consider these solubility values to maintain at least 90% saturation in the solution. The section presents a formula for chlorine dose calculation and a flowchart demonstrating chlorine gas dissolution in water, ensuring process control and optimization.

Installation and safety guidelines mandate adherence to IS 10553 Part 1 for handling, storage, and safety of chlorine cylinders and drums. This section covers the recommended rates of chlorine withdrawal from different container sizes at specified ambient temperatures to prevent operational hazards like liquid chlorine freezing. For installations with more than three cylinders, connection in groups is advised to allow sequential group replacement without process interruption. Safety advice includes proper cylinder storage, ventilation, and the use of personal protective equipment.

Materials for ancillary equipment are specified, with metallic parts contacting chlorine gas requiring silver-plated brass or nickel, and stainless steel allowed for dry chlorine. Non-metallic parts should be glass, ebonite, or resistant plastics. Components include chlorine gas filters, pressure reducing valves, manometers, regulating valves, moisture traps, pressure gauges, and stop valves. Tables provide rates of chlorine withdrawal corresponding to temperature and container size. A flowchart illustrates the sequence of chlorine gas processing through ancillary devices for safe delivery.

Control panels must be constructed from fiberglass with resistance to moisture, chlorine, and acid, or mild steel coated with three epoxy paint layers for corrosion protection. Tables summarize chlorine solubility in water and rates of chlorine withdrawal relative to temperature and container size, critical for sizing control and safety systems. The section emphasizes the interrelation between solubility, dosing control, and safety compliance according to IS 10553 Part 4 and Part 1.

Solutionizer towers are to be fabricated from corrosion-resistant materials such as glazed porcelain, PVC, or rubber-lined mild steel. Packing media include round, water-worn pebbles, pumicestone, porcelain, or acid-resistant plastic rashing rings. Water supply must maintain a constant head to ensure stable flow, and outlet design should maximize flow rate while minimizing turbulence. The section provides a fundamental flow equation and highlights design considerations for effective chlorine gas absorption.

Manometer tubes should be made from phosphorus deoxidised non-arsenical copper, arsenical copper, or carbon steel, conforming to respective IS standards. Minimum wall thickness and tolerances are tabulated based on tube diameter and material. The tubes must withstand pressure differences without failure. The basic pressure calculation formula using fluid density, gravity, and fluid column height is provided to assist in pressure measurement and system design.

While IS 10553 Part 4 does not specify a direct clause for moisture seals, it details associated components such as moisture traps and their material requirements. Metallic parts in contact with chlorine must be silver-plated brass, nickel, or stainless steel (dry chlorine only), while non-metallic parts include glass, ebonite, and acid-resistant plastics. Proper moisture sealing prevents water ingress into chlorine gas lines, preserving system integrity. Chlorine solubility data informs moisture seal design to minimize contamination.

Maintaining a constant water head in the solutionizer tower is essential for steady chlorine dissolution and process stability. This section explains the hydraulic principles behind constant head supply, highlighting the impact on chlorine solubility and reaction rates. It includes a formula relating flow rate to cross-sectional area and head, supported by a flowchart depicting water supply and chlorine dissolution steps.

For installations using more than three chlorine cylinders, connections must be arranged in groups to allow replacement of one group at a time without interrupting the chlorination process. Metallic parts must adhere to material specifications ensuring corrosion resistance. Ancillary components like filters, valves, and manometers are detailed. Installation and safety are aligned with IS 10553 Part 1. A flow diagram illustrates the sequential connection of cylinder groups to the chlorine supply line.

Chlorine discharge rates are governed by container size and ambient temperature to prevent liquid chlorine freezing. Tabled limits specify maximum safe withdrawal rates for 45 kg and 67 kg cylinders and tonne containers at various temperatures. Adherence to these limits ensures safe operation and uninterrupted chlorine supply. The section cross-references chlorine solubility data for process design and emphasizes compliance with IS 10553 Part 1 for safety.

Safety and maintenance recommendations include following IS 10553 Part 1 for handling and storage of chlorine cylinders and drums, grouping cylinders in sets for ease of replacement, and monitoring withdrawal rates as per temperature guidelines. Regular inspections, leak detection, proper ventilation, secure storage, and use of personal protective equipment are stressed. A flowchart outlines the process of cylinder storage, grouped withdrawal, temperature monitoring, inspection, and safety enforcement to maintain operational safety.