Technical Specification for Gateway Running Water Filters

1. Introduction

   This document outlines the technical specifications for Gateway River Filters, designed for effective filtration of river water in various applications, from municipal water treatment to industrial use and river-based recreational activities.

2. Purpose

   The purpose of these filters is to remove suspended particles, bacteria, viruses, and various contaminants from river water, ensuring it meets the standards for drinking, industrial use, or environmental protection.

3. Filter Types & Configurations

   • Gravity Filters

     • Design: Utilizes gravity to pass water through filter media, suitable for camping or remote locations without power.
     • Media: Includes ceramic, activated carbon, and sometimes hollow fibre membranes.
     • Flow Rate: Typically between 1-3 liters per minute, depending on head pressure and media condition.
     • Maintenance: Requires periodic backwashing or media replacement.

   • Self-Cleaning Automatic Filters

     • Design: Engineered for continuous operation in industrial settings, these filters automatically clean themselves to maintain flow without manual intervention.
     • Media: Stainless steel screens or disc filters, with mesh sizes ranging from 10 to 500 microns.
     • Flow Rate: Can handle variable volumes dependant on cubic mass of waterflow.
     • Maintenance: Automated cleaning cycles reduce maintenance; however, periodic checks for wear or damage are necessary.

   • Multi-Media Filters

     • Design: Layers of different materials (sand, anthracite, garnet) for in-depth filtration.
     • Media: Typically includes sand (mono or dual layered), anthracite for the top layer in dual media, and supports like gravel.
     • Flow Rate: Variable based on bed depth and media size but optimized for high efficiency with medium-rate filtration (e.g., up to 25 m³/m²/h).
     • Maintenance: Backwashing required, frequency depends on water quality and use.

4. Performance Specifications

   • Filtration Efficiency:
     • Removal of particles down to 1 micron for basic models, with specialized filters achieving submicron filtration.
     • Pathogenic bacteria reduction by 99.99% or more, depending on the filter media used.
     • Virus filtration capability in advanced models or with additional treatment steps like UV or chemical.
   • Flow Rate: Must be adjustable or selectable to match the application's demand, whether for slow filtration in small-scale systems or high throughput in industrial setups.
   • Pressure Drop: Should be minimized to reduce energy consumption, typically less than 0.5 bar for clean filters.

5. Material Specifications

   • Filter Media:
     • Sand: Must conform to AWWA B100-16 standards, with specific gradings for mono, dual, or mixed-media applications.
     • Activated Carbon: For taste, odour, and colour removal, with high adsorption capacity.
     • Ceramic: For microbial filtration, with micropores less than 0.2 microns.
     • Membranes: When used, should have a high rejection rate for contaminants while maintaining good water flux.
   • Housing:
     • Materials: Glass for durability, with a life expectancy of 10-40 years based on quality.
     • Pressure Rating: Must withstand operational pressures with safety margins, typically up to 6 bar.

6. Installation and Operational Requirements

   • Installation:
     • Consideration for backwashing infrastructure, space for media replacement, and access for maintenance.
     • Proper anchoring or support to handle water flow and potential pressure surges.
   • Operation:
     • Regular monitoring of flow rates, pressure differentials, and water quality post-filtration.
     • Scheduled maintenance including backwashing, media checks, or replacement.

7. Compliance and Standards

   • Certifications: Filters should comply with relevant standards like NSF/ANSI 53 for drinking water treatment units or local equivalents for industrial applications.
   • Environmental Impact: Materials should be selected for minimal environmental impact, considering disposal and lifecycle assessment.

8. Warranty and Support

   • Warranty: Typically, a 10-year warranty on housing with conditions for use and maintenance.
   • Support: Availability of technical support, manuals, and training for operation and maintenance.

This specification document aims to guide the selection, installation, and maintenance of gateway river filters, ensuring that the water quality meets the necessary standards for its intended use.