Many agrochemical active ingredients are synthesised in continuous or semi-continuous reactors under precise temperature, pressure and reactant feed rate control. The reactor control systems use pneumatic valves for reactant addition, pressure relief, temperature control and emergency shutdown. In a continuous agrochemical reactor, loss of instrument air is not just a production stoppage — it is a potential safety event. When instrument air fails, pneumatic control valves lose position. In a reactor where an exothermic reaction is in progress — many agrochemical synthesis reactions involve hazardous exothermic steps — loss of the temperature control valve, cooling water flow control or reactant feed shut-off creates conditions that require immediate manual intervention by trained operators in full PPE. The emergency manual shutdown procedure for a continuous agrochemical reactor is a significant safety operation, quite different from simply stopping a textile loom or a packaging line. The instrument air supply for agrochemical reactors must have a receiver tank sized for 15–30 minutes of demand at operating pressure, and 24/7 emergency response from a locally-based compressor service team.

Agrochemical formulation facilities operate with solvents including toluene, xylene, methanol, isopropanol and acetone at varying concentrations depending on the formulation type and the ventilation of the work area. These solvent vapours, if present in the ambient air around the compressor, are drawn into the compressor inlet with the inlet air. Solvent vapours contaminate compressor oil in oil-lubricated screw compressors. Even at low concentrations, solvent contamination breaks down the additive package in the compressor oil, dramatically reducing oil life and increasing the risk of deposit formation in the oil separator element and oil cooler. Solvent-contaminated compressed air in the downstream piping and receiver tank can accumulate at concentrations that create a fire hazard when the air is subsequently used near ignition sources in the formulation area. Solvents also attack nitrile and neoprene rubber O-rings and hose fittings in the compressed air distribution system, causing premature failure and air leaks. Agrochemical plants in Vapi must place compressors in well-ventilated locations, away from formulation areas, with inlet air drawn from a clean source if possible.

Agrochemical manufacturing effluent contains pesticide synthesis by-products, solvents, reaction intermediates and washing solutions that give the effluent an extremely high Chemical Oxygen Demand (COD) — often 5,000–50,000 mg/L or higher in concentrated process streams before dilution with general plant effluent. The biological treatment stage of an agrochemical plant ETP must supply oxygen at a rate sufficient to sustain the activated sludge bacteria that break down this high-COD effluent. The Roots Blower for agrochemical plant ETP aeration must be sized significantly larger than blowers for chemical or food plant ETPs of similar volume. GPCB (Gujarat Pollution Control Board) holds agrochemical plants to strict effluent quality standards — a failed ETP can result in GPCB action including show-cause notice and plant closure. R R Enterprise is the only local Roots Blower manufacturer in the Vapi–Silvassa belt and provides emergency replacement for agrochemical ETP blowers.